Source code for psychopy.tools.gltools

#!/usr/bin/env python
# -*- coding: utf-8 -*-
"""OpenGL related helper functions.

"""

# Part of the PsychoPy library
# Copyright (C) 2002-2018 Jonathan Peirce (C) 2019-2021 Open Science Tools Ltd.
# Distributed under the terms of the GNU General Public License (GPL).

__all__ = [
    'createProgram',
    'createProgramObjectARB',
    'compileShader',
    'compileShaderObjectARB',
    'embedShaderSourceDefs',
    'deleteObject',
    'deleteObjectARB',
    'attachShader',
    'attachObjectARB',
    'detachShader',
    'detachObjectARB',
    'linkProgram',
    'linkProgramObjectARB',
    'validateProgram',
    'validateProgramARB',
    'useProgram',
    'useProgramObjectARB',
    'getInfoLog',
    'getUniformLocations',
    'getAttribLocations',
    'createQueryObject',
    'QueryObjectInfo',
    'beginQuery',
    'endQuery',
    'getQuery',
    'getAbsTimeGPU',
    'createFBO',
    'attach',
    'isComplete',
    'deleteFBO',
    'blitFBO',
    'useFBO',
    'createRenderbuffer',
    'deleteRenderbuffer',
    'createTexImage2D',
    'createTexImage2DMultisample',
    'deleteTexture',
    'VertexArrayInfo',
    'createVAO',
    'drawVAO',
    'deleteVAO',
    'VertexBufferInfo',
    'createVBO',
    'bindVBO',
    'unbindVBO',
    'mapBuffer',
    'unmapBuffer',
    'deleteVBO',
    'setVertexAttribPointer',
    'enableVertexAttribArray',
    'disableVertexAttribArray',
    'createMaterial',
    'useMaterial',
    'createLight',
    'useLights',
    'setAmbientLight',
    'ObjMeshInfo',
    'loadObjFile',
    'loadMtlFile',
    'createUVSphere',
    'createPlane',
    'createMeshGridFromArrays',
    'createMeshGrid',
    'createBox',
    'transformMeshPosOri',
    'calculateVertexNormals',
    'getIntegerv',
    'getFloatv',
    'getString',
    'getOpenGLInfo',
    'createTexImage2D',
    'createTexImage2dFromFile',
    'bindTexture',
    'unbindTexture',
    'createCubeMap',
    'TexCubeMap',
    'getModelViewMatrix',
    'getProjectionMatrix'
]

import ctypes
from io import StringIO
from collections import namedtuple
import pyglet.gl as GL  # using Pyglet for now
from contextlib import contextmanager
from PIL import Image
import numpy as np
import os, sys
import warnings
import psychopy.tools.mathtools as mt
from psychopy.visual.helpers import setColor

# create a query counter to get absolute GPU time

QUERY_COUNTER = None  # prevent genQueries from being called


# compatible Numpy and OpenGL types for common GL type enums
GL_COMPAT_TYPES = {
    GL.GL_FLOAT: (np.float32, GL.GLfloat),
    GL.GL_DOUBLE: (np.float64, GL.GLdouble),
    GL.GL_UNSIGNED_SHORT: (np.uint16, GL.GLushort),
    GL.GL_UNSIGNED_INT: (np.uint32, GL.GLuint),
    GL.GL_INT: (np.int32, GL.GLint),
    GL.GL_SHORT: (np.int16, GL.GLshort),
    GL.GL_HALF_FLOAT: (np.float16, GL.GLhalfARB),
    GL.GL_UNSIGNED_BYTE: (np.uint8, GL.GLubyte),
    GL.GL_BYTE: (np.int8, GL.GLbyte),
    np.float32: (GL.GL_FLOAT, GL.GLfloat),
    np.float64: (GL.GL_DOUBLE, GL.GLdouble),
    np.uint16: (GL.GL_UNSIGNED_SHORT, GL.GLushort),
    np.uint32: (GL.GL_UNSIGNED_INT, GL.GLuint),
    np.int32: (GL.GL_INT, GL.GLint),
    np.int16: (GL.GL_SHORT, GL.GLshort),
    np.float16: (GL.GL_HALF_FLOAT, GL.GLhalfARB),
    np.uint8: (GL.GL_UNSIGNED_BYTE, GL.GLubyte),
    np.int8: (GL.GL_BYTE, GL.GLbyte)
}


# -------------------------------
# Shader Program Helper Functions
# -------------------------------
#

[docs]def createProgram(): """Create an empty program object for shaders. Returns ------- int OpenGL program object handle retrieved from a `glCreateProgram` call. Examples -------- Building a program with vertex and fragment shader attachments:: myProgram = createProgram() # new shader object # compile vertex and fragment shader sources vertexShader = compileShader(vertShaderSource, GL.GL_VERTEX_SHADER) fragmentShader = compileShader(fragShaderSource, GL.GL_FRAGMENT_SHADER) # attach shaders to program attachShader(myProgram, vertexShader) attachShader(myProgram, fragmentShader) # link the shader, makes `myProgram` attachments executable by their # respective processors and available for use linkProgram(myProgram) # optional, validate the program validateProgram(myProgram) # optional, detach and discard shader objects detachShader(myProgram, vertexShader) detachShader(myProgram, fragmentShader) deleteObject(vertexShader) deleteObject(fragmentShader) You can install the program for use in the current rendering state by calling:: useProgram(myShader) # OR glUseProgram(myShader) # set uniforms/attributes and start drawing here ... """ return GL.glCreateProgram()
[docs]def createProgramObjectARB(): """Create an empty program object for shaders. This creates an *Architecture Review Board* (ARB) program variant which is compatible with older GLSL versions and OpenGL coding practices (eg. immediate mode) on some platforms. Use *ARB variants of shader helper functions (eg. `compileShaderObjectARB` instead of `compileShader`) when working with these ARB program objects. This was included for legacy support of existing PsychoPy shaders. However, it is recommended that you use :func:`createShader` and follow more recent OpenGL design patterns for new code (if possible of course). Returns ------- int OpenGL program object handle retrieved from a `glCreateProgramObjectARB` call. Examples -------- Building a program with vertex and fragment shader attachments:: myProgram = createProgramObjectARB() # new shader object # compile vertex and fragment shader sources vertexShader = compileShaderObjectARB( vertShaderSource, GL.GL_VERTEX_SHADER_ARB) fragmentShader = compileShaderObjectARB( fragShaderSource, GL.GL_FRAGMENT_SHADER_ARB) # attach shaders to program attachObjectARB(myProgram, vertexShader) attachObjectARB(myProgram, fragmentShader) # link the shader, makes `myProgram` attachments executable by their # respective processors and available for use linkProgramObjectARB(myProgram) # optional, validate the program validateProgramARB(myProgram) # optional, detach and discard shader objects detachObjectARB(myProgram, vertexShader) detachObjectARB(myProgram, fragmentShader) deleteObjectARB(vertexShader) deleteObjectARB(fragmentShader) Use the program in the current OpenGL state:: useProgramObjectARB(myProgram) """ return GL.glCreateProgramObjectARB()
[docs]def compileShader(shaderSrc, shaderType): """Compile shader GLSL code and return a shader object. Shader objects can then be attached to programs an made executable on their respective processors. Parameters ---------- shaderSrc : str, list of str GLSL shader source code. shaderType : GLenum Shader program type (eg. `GL_VERTEX_SHADER`, `GL_FRAGMENT_SHADER`, `GL_GEOMETRY_SHADER`, etc.) Returns ------- int OpenGL shader object handle retrieved from a `glCreateShader` call. Examples -------- Compiling GLSL source code and attaching it to a program object:: # GLSL vertex shader source vertexSource = \ ''' #version 330 core layout (location = 0) in vec3 vertexPos; void main() { gl_Position = vec4(vertexPos, 1.0); } ''' # compile it, specifying `GL_VERTEX_SHADER` vertexShader = compileShader(vertexSource, GL.GL_VERTEX_SHADER) attachShader(myProgram, vertexShader) # attach it to `myProgram` """ shaderId = GL.glCreateShader(shaderType) if isinstance(shaderSrc, (list, tuple,)): nSources = len(shaderSrc) srcPtr = (ctypes.c_char_p * nSources)() srcPtr[:] = [i.encode() for i in shaderSrc] else: nSources = 1 srcPtr = ctypes.c_char_p(shaderSrc.encode()) GL.glShaderSource( shaderId, nSources, ctypes.cast( ctypes.byref(srcPtr), ctypes.POINTER(ctypes.POINTER(ctypes.c_char))), None) GL.glCompileShader(shaderId) result = GL.GLint() GL.glGetShaderiv( shaderId, GL.GL_COMPILE_STATUS, ctypes.byref(result)) if result.value == GL.GL_FALSE: # failed to compile for whatever reason sys.stderr.write(getInfoLog(shaderId) + '\n') deleteObject(shaderId) raise RuntimeError("Shader compilation failed, check log output.") return shaderId
[docs]def compileShaderObjectARB(shaderSrc, shaderType): """Compile shader GLSL code and return a shader object. Shader objects can then be attached to programs an made executable on their respective processors. Parameters ---------- shaderSrc : str, list of str GLSL shader source code text. shaderType : GLenum Shader program type. Must be *_ARB enums such as `GL_VERTEX_SHADER_ARB`, `GL_FRAGMENT_SHADER_ARB`, `GL_GEOMETRY_SHADER_ARB`, etc. Returns ------- int OpenGL shader object handle retrieved from a `glCreateShaderObjectARB` call. """ shaderId = GL.glCreateShaderObjectARB(shaderType) if isinstance(shaderSrc, (list, tuple,)): nSources = len(shaderSrc) srcPtr = (ctypes.c_char_p * nSources)() srcPtr[:] = [i.encode() for i in shaderSrc] else: nSources = 1 srcPtr = ctypes.c_char_p(shaderSrc.encode()) GL.glShaderSourceARB( shaderId, nSources, ctypes.cast( ctypes.byref(srcPtr), ctypes.POINTER(ctypes.POINTER(ctypes.c_char))), None) GL.glCompileShaderARB(shaderId) result = GL.GLint() GL.glGetObjectParameterivARB( shaderId, GL.GL_OBJECT_COMPILE_STATUS_ARB, ctypes.byref(result)) if result.value == GL.GL_FALSE: # failed to compile for whatever reason sys.stderr.write(getInfoLog(shaderId) + '\n') deleteObjectARB(shaderId) raise RuntimeError("Shader compilation failed, check log output.") return shaderId
[docs]def embedShaderSourceDefs(shaderSrc, defs): """Embed preprocessor definitions into GLSL source code. This function generates and inserts ``#define`` statements into existing GLSL source code, allowing one to use GLSL preprocessor statements to alter program source at compile time. Passing ``{'MAX_LIGHTS': 8, 'NORMAL_MAP': False}`` to `defs` will create and insert the following ``#define`` statements into `shaderSrc`:: #define MAX_LIGHTS 8 #define NORMAL_MAP 0 As per the GLSL specification, the ``#version`` directive must be specified at the top of the file before any other statement (with the exception of comments). If a ``#version`` directive is present, generated ``#define`` statements will be inserted starting at the following line. If no ``#version`` directive is found in `shaderSrc`, the statements will be prepended to `shaderSrc`. Using preprocessor directives, multiple shader program routines can reside in the same source text if enclosed by ``#ifdef`` and ``#endif`` statements as shown here:: #ifdef VERTEX // vertex shader code here ... #endif #ifdef FRAGMENT // pixel shader code here ... #endif Both the vertex and fragment shader can be built from the same GLSL code listing by setting either ``VERTEX`` or ``FRAGMENT`` as `True`:: vertexShader = gltools.compileShaderObjectARB( gltools.embedShaderSourceDefs(glslSource, {'VERTEX': True}), GL.GL_VERTEX_SHADER_ARB) fragmentShader = gltools.compileShaderObjectARB( gltools.embedShaderSourceDefs(glslSource, {'FRAGMENT': True}), GL.GL_FRAGMENT_SHADER_ARB) In addition, ``#ifdef`` blocks can be used to prune render code paths. Here, this GLSL snippet shows a shader having diffuse color sampled from a texture is conditional on ``DIFFUSE_TEXTURE`` being `True`, if not, the material color is used instead:: #ifdef DIFFUSE_TEXTURE uniform sampler2D diffuseTexture; #endif ... #ifdef DIFFUSE_TEXTURE // sample color from texture vec4 diffuseColor = texture2D(diffuseTexture, gl_TexCoord[0].st); #else // code path for no textures, just output material color vec4 diffuseColor = gl_FrontMaterial.diffuse; #endif This avoids needing to provide two separate GLSL program sources to build shaders to handle cases where a diffuse texture is or isn't used. Parameters ---------- shaderSrc : str GLSL shader source code. defs : dict Names and values to generate ``#define`` statements. Keys must all be valid GLSL preprocessor variable names of type `str`. Values can only be `int`, `float`, `str`, `bytes`, or `bool` types. Boolean values `True` and `False` are converted to integers `1` and `0`, respectively. Returns ------- str GLSL source code with ``#define`` statements inserted. Examples -------- Defining ``MAX_LIGHTS`` as `8` in a fragment shader program at runtime:: fragSrc = embedShaderSourceDefs(fragSrc, {'MAX_LIGHTS': 8}) fragShader = compileShaderObjectARB(fragSrc, GL_FRAGMENT_SHADER_ARB) """ # generate GLSL `#define` statements glslDefSrc = "" for varName, varValue in defs.items(): if not isinstance(varName, str): raise ValueError("Definition name must be type `str`.") if isinstance(varValue, (int, bool,)): varValue = int(varValue) elif isinstance(varValue, (float,)): pass #varValue = varValue elif isinstance(varValue, bytes): varValue = '"{}"'.format(varValue.decode('UTF-8')) elif isinstance(varValue, str): varValue = '"{}"'.format(varValue) else: raise TypeError("Invalid type for value of `{}`.".format(varName)) glslDefSrc += '#define {n} {v}\n'.format(n=varName, v=varValue) # find where the `#version` directive occurs versionDirIdx = shaderSrc.find("#version") if versionDirIdx != -1: srcSplitIdx = shaderSrc.find("\n", versionDirIdx) + 1 # after newline srcOut = shaderSrc[:srcSplitIdx] + glslDefSrc + shaderSrc[srcSplitIdx:] else: # no version directive in source, just prepend defines srcOut = glslDefSrc + shaderSrc return srcOut
[docs]def deleteObject(obj): """Delete a shader or program object. Parameters ---------- obj : int Shader or program object handle. Must have originated from a :func:`createProgram`, :func:`compileShader`, `glCreateProgram` or `glCreateShader` call. """ if GL.glIsShader(obj): GL.glDeleteShader(obj) elif GL.glIsProgram(obj): GL.glDeleteProgram(obj) else: raise ValueError('Cannot delete, not a program or shader object.')
[docs]def deleteObjectARB(obj): """Delete a program or shader object. Parameters ---------- obj : int Program handle to attach `shader` to. Must have originated from a :func:`createProgramObjectARB`, :func:`compileShaderObjectARB, `glCreateProgramObjectARB` or `glCreateShaderObjectARB` call. """ GL.glDeleteObjectARB(obj)
[docs]def attachShader(program, shader): """Attach a shader to a program. Parameters ---------- program : int Program handle to attach `shader` to. Must have originated from a :func:`createProgram` or `glCreateProgram` call. shader : int Handle of shader object to attach. Must have originated from a :func:`compileShader` or `glCreateShader` call. """ if not GL.glIsProgram(program): raise ValueError("Value `program` is not a program object.") elif not GL.glIsShader(shader): raise ValueError("Value `shader` is not a shader object.") else: GL.glAttachShader(program, shader)
[docs]def attachObjectARB(program, shader): """Attach a shader object to a program. Parameters ---------- program : int Program handle to attach `shader` to. Must have originated from a :func:`createProgramObjectARB` or `glCreateProgramObjectARB` call. shader : int Handle of shader object to attach. Must have originated from a :func:`compileShaderObjectARB` or `glCreateShaderObjectARB` call. """ if not GL.glIsProgram(program): raise ValueError("Value `program` is not a program object.") elif not GL.glIsShader(shader): raise ValueError("Value `shader` is not a shader object.") else: GL.glAttachObjectARB(program, shader)
[docs]def detachShader(program, shader): """Detach a shader object from a program. Parameters ---------- program : int Program handle to detach `shader` from. Must have originated from a :func:`createProgram` or `glCreateProgram` call. shader : int Handle of shader object to detach. Must have been previously attached to `program`. """ if not GL.glIsProgram(program): raise ValueError("Value `program` is not a program.") elif not GL.glIsShader(shader): raise ValueError("Value `shader` is not a shader object.") else: GL.glDetachShader(program, shader)
[docs]def detachObjectARB(program, shader): """Detach a shader object from a program. Parameters ---------- program : int Program handle to detach `shader` from. Must have originated from a :func:`createProgramObjectARB` or `glCreateProgramObjectARB` call. shader : int Handle of shader object to detach. Must have been previously attached to `program`. """ if not GL.glIsProgram(program): raise ValueError("Value `program` is not a program.") elif not GL.glIsShader(shader): raise ValueError("Value `shader` is not a shader object.") else: GL.glDetachObjectARB(program, shader)
[docs]def linkProgram(program): """Link a shader program. Any attached shader objects will be made executable to run on associated GPU processor units when the program is used. Parameters ---------- program : int Program handle to link. Must have originated from a :func:`createProgram` or `glCreateProgram` call. Raises ------ ValueError Specified `program` handle is invalid. RuntimeError Program failed to link. Log will be dumped to `sterr`. """ if GL.glIsProgram(program): GL.glLinkProgram(program) else: raise ValueError("Value `program` is not a shader program.") # check for errors result = GL.GLint() GL.glGetProgramiv(program, GL.GL_LINK_STATUS, ctypes.byref(result)) if result.value == GL.GL_FALSE: # failed to link for whatever reason sys.stderr.write(getInfoLog(program) + '\n') raise RuntimeError( 'Failed to link shader program. Check log output.')
[docs]def linkProgramObjectARB(program): """Link a shader program object. Any attached shader objects will be made executable to run on associated GPU processor units when the program is used. Parameters ---------- program : int Program handle to link. Must have originated from a :func:`createProgramObjectARB` or `glCreateProgramObjectARB` call. Raises ------ ValueError Specified `program` handle is invalid. RuntimeError Program failed to link. Log will be dumped to `sterr`. """ if GL.glIsProgram(program): GL.glLinkProgramARB(program) else: raise ValueError("Value `program` is not a shader program.") # check for errors result = GL.GLint() GL.glGetObjectParameterivARB( program, GL.GL_OBJECT_LINK_STATUS_ARB, ctypes.byref(result)) if result.value == GL.GL_FALSE: # failed to link for whatever reason sys.stderr.write(getInfoLog(program) + '\n') raise RuntimeError( 'Failed to link shader program. Check log output.')
[docs]def validateProgram(program): """Check if the program can execute given the current OpenGL state. Parameters ---------- program : int Handle of program to validate. Must have originated from a :func:`createProgram` or `glCreateProgram` call. """ # check validation info result = GL.GLint() GL.glValidateProgram(program) GL.glGetProgramiv(program, GL.GL_VALIDATE_STATUS, ctypes.byref(result)) if result.value == GL.GL_FALSE: sys.stderr.write(getInfoLog(program) + '\n') raise RuntimeError('Shader program validation failed.')
[docs]def validateProgramARB(program): """Check if the program can execute given the current OpenGL state. If validation fails, information from the driver is dumped giving the reason. Parameters ---------- program : int Handle of program object to validate. Must have originated from a :func:`createProgramObjectARB` or `glCreateProgramObjectARB` call. """ # check validation info result = GL.GLint() GL.glValidateProgramARB(program) GL.glGetObjectParameterivARB( program, GL.GL_OBJECT_VALIDATE_STATUS_ARB, ctypes.byref(result)) if result.value == GL.GL_FALSE: sys.stderr.write(getInfoLog(program) + '\n') raise RuntimeError('Shader program validation failed.')
[docs]def useProgram(program): """Use a program object's executable shader attachments in the current OpenGL rendering state. In order to install the program object in the current rendering state, a program must have been successfully linked by calling :func:`linkProgram` or `glLinkProgram`. Parameters ---------- program : int Handle of program to use. Must have originated from a :func:`createProgram` or `glCreateProgram` call and was successfully linked. Passing `0` or `None` disables shader programs. Examples -------- Install a program for use in the current rendering state:: useProgram(myShader) Disable the current shader program by specifying `0`:: useProgram(0) """ if program is None: program = 0 if GL.glIsProgram(program) or program == 0: GL.glUseProgram(program) else: raise ValueError('Specified `program` is not a program object.')
[docs]def useProgramObjectARB(program): """Use a program object's executable shader attachments in the current OpenGL rendering state. In order to install the program object in the current rendering state, a program must have been successfully linked by calling :func:`linkProgramObjectARB` or `glLinkProgramObjectARB`. Parameters ---------- program : int Handle of program object to use. Must have originated from a :func:`createProgramObjectARB` or `glCreateProgramObjectARB` call and was successfully linked. Passing `0` or `None` disables shader programs. Examples -------- Install a program for use in the current rendering state:: useProgramObjectARB(myShader) Disable the current shader program by specifying `0`:: useProgramObjectARB(0) Notes ----- Some drivers may support using `glUseProgram` for objects created by calling :func:`createProgramObjectARB` or `glCreateProgramObjectARB`. """ if program is None: program = 0 if GL.glIsProgram(program) or program == 0: GL.glUseProgramObjectARB(program) else: raise ValueError('Specified `program` is not a program object.')
[docs]def getInfoLog(obj): """Get the information log from a shader or program. This retrieves a text log from the driver pertaining to the shader or program. For instance, a log can report shader compiler output or validation results. The verbosity and formatting of the logs are platform-dependent, where one driver may provide more information than another. This function works with both standard and ARB program object variants. Parameters ---------- obj : int Program or shader to retrieve a log from. If a shader, the handle must have originated from a :func:`compileShader`, `glCreateShader`, :func:`createProgramObjectARB` or `glCreateProgramObjectARB` call. If a program, the handle must have came from a :func:`createProgram`, :func:`createProgramObjectARB`, `glCreateProgram` or `glCreateProgramObjectARB` call. Returns ------- str Information log data. Logs can be empty strings if the driver has no information available. """ logLength = GL.GLint() if GL.glIsShader(obj) == GL.GL_TRUE: GL.glGetShaderiv( obj, GL.GL_INFO_LOG_LENGTH, ctypes.byref(logLength)) elif GL.glIsProgram(obj) == GL.GL_TRUE: GL.glGetProgramiv( obj, GL.GL_INFO_LOG_LENGTH, ctypes.byref(logLength)) else: raise ValueError( "Specified value of `obj` is not a shader or program.") logBuffer = ctypes.create_string_buffer(logLength.value) GL.glGetShaderInfoLog(obj, logLength, None, logBuffer) return logBuffer.value.decode('UTF-8')
[docs]def getUniformLocations(program, builtins=False): """Get uniform names and locations from a given shader program object. This function works with both standard and ARB program object variants. Parameters ---------- program : int Handle of program to retrieve uniforms. Must have originated from a :func:`createProgram`, :func:`createProgramObjectARB`, `glCreateProgram` or `glCreateProgramObjectARB` call. builtins : bool, optional Include built-in GLSL uniforms (eg. `gl_ModelViewProjectionMatrix`). Default is `False`. Returns ------- dict Uniform names and locations. """ if not GL.glIsProgram(program): raise ValueError( "Specified value of `program` is not a program object handle.") arraySize = GL.GLint() nameLength = GL.GLsizei() # cache uniform locations to avoid looking them up before setting them nUniforms = GL.GLint() GL.glGetProgramiv(program, GL.GL_ACTIVE_UNIFORMS, ctypes.byref(nUniforms)) unifLoc = None if nUniforms.value > 0: maxUniformLength = GL.GLint() GL.glGetProgramiv( program, GL.GL_ACTIVE_UNIFORM_MAX_LENGTH, ctypes.byref(maxUniformLength)) unifLoc = {} for uniformIdx in range(nUniforms.value): unifType = GL.GLenum() unifName = (GL.GLchar * maxUniformLength.value)() GL.glGetActiveUniform( program, uniformIdx, maxUniformLength, ctypes.byref(nameLength), ctypes.byref(arraySize), ctypes.byref(unifType), unifName) # get location loc = GL.glGetUniformLocation(program, unifName) # don't include if -1, these are internal types like 'gl_Vertex' if not builtins: if loc != -1: unifLoc[unifName.value] = loc else: unifLoc[unifName.value] = loc return unifLoc
[docs]def getAttribLocations(program, builtins=False): """Get attribute names and locations from the specified program object. This function works with both standard and ARB program object variants. Parameters ---------- program : int Handle of program to retrieve attributes. Must have originated from a :func:`createProgram`, :func:`createProgramObjectARB`, `glCreateProgram` or `glCreateProgramObjectARB` call. builtins : bool, optional Include built-in GLSL attributes (eg. `gl_Vertex`). Default is `False`. Returns ------- dict Attribute names and locations. """ if not GL.glIsProgram(program): raise ValueError( "Specified value of `program` is not a program object handle.") arraySize = GL.GLint() nameLength = GL.GLsizei() nAttribs = GL.GLint() GL.glGetProgramiv(program, GL.GL_ACTIVE_ATTRIBUTES, ctypes.byref(nAttribs)) attribLoc = None if nAttribs.value > 0: maxAttribLength = GL.GLint() GL.glGetProgramiv( program, GL.GL_ACTIVE_ATTRIBUTE_MAX_LENGTH, ctypes.byref(maxAttribLength)) attribLoc = {} for attribIdx in range(nAttribs.value): attribType = GL.GLenum() attribName = (GL.GLchar * maxAttribLength.value)() GL.glGetActiveAttrib( program, attribIdx, maxAttribLength, ctypes.byref(nameLength), ctypes.byref(arraySize), ctypes.byref(attribType), attribName) # get location loc = GL.glGetAttribLocation(program, attribName.value) # don't include if -1, these are internal types like 'gl_Vertex' if not builtins: if loc != -1: attribLoc[attribName.value] = loc else: attribLoc[attribName.value] = loc return attribLoc
# ----------------------------------- # GL Query Objects # -----------------------------------
[docs]class QueryObjectInfo(object): """Object for querying information. This includes GPU timing information.""" __slots__ = ['name', 'target']
[docs] def __init__(self, name, target): self.name = name self.target = target
def isValid(self): """Check if the name associated with this object is valid.""" return GL.glIsQuery(self.name) == GL.GL_TRUE
[docs]def createQueryObject(target=GL.GL_TIME_ELAPSED): """Create a GL query object. Parameters ---------- target : Glenum or int Target for the query. Returns ------- QueryObjectInfo Query object. Examples -------- Get GPU time elapsed executing rendering/GL calls associated with some stimuli (this is not the difference in absolute time between consecutive `beginQuery` and `endQuery` calls!):: # create a new query object qGPU = createQueryObject(GL_TIME_ELAPSED) beginQuery(query) myStim.draw() # OpenGL calls here endQuery(query) # get time elapsed in seconds spent on the GPU timeRendering = getQueryValue(qGPU) * 1e-9 You can also use queries to test if vertices are occluded, as their samples would be rejected during depth testing:: drawVAO(shape0, GL_TRIANGLES) # draw the first object # check if the object was completely occluded qOcclusion = createQueryObject(GL_ANY_SAMPLES_PASSED) # draw the next shape within query context beginQuery(qOcclusion) drawVAO(shape1, GL_TRIANGLES) # draw the second object endQuery(qOcclusion) isOccluded = getQueryValue(qOcclusion) == 1 This can be leveraged to perform occlusion testing/culling, where you can render a `cheap` version of your mesh/shape, then the more expensive version if samples were passed. """ result = GL.GLuint() GL.glGenQueries(1, ctypes.byref(result)) return QueryObjectInfo(result, target)
[docs]def beginQuery(query): """Begin query. Parameters ---------- query : QueryObjectInfo Query object descriptor returned by :func:`createQueryObject`. """ if isinstance(query, (QueryObjectInfo,)): GL.glBeginQuery(query.target, query.name) else: raise TypeError('Type of `query` must be `QueryObjectInfo`.')
[docs]def endQuery(query): """End a query. Parameters ---------- query : QueryObjectInfo Query object descriptor returned by :func:`createQueryObject`, previously passed to :func:`beginQuery`. """ if isinstance(query, (QueryObjectInfo,)): GL.glEndQuery(query.target) else: raise TypeError('Type of `query` must be `QueryObjectInfo`.')
[docs]def getQuery(query): """Get the value stored in a query object. Parameters ---------- query : QueryObjectInfo Query object descriptor returned by :func:`createQueryObject`, previously passed to :func:`endQuery`. """ params = GL.GLuint64(0) if isinstance(query, QueryObjectInfo): GL.glGetQueryObjectui64v( query.name, GL.GL_QUERY_RESULT, ctypes.byref(params)) return params.value else: raise TypeError('Argument `query` must be `QueryObjectInfo` instance.')
[docs]def getAbsTimeGPU(): """Get the absolute GPU time in nanoseconds. Returns ------- int Time elapsed in nanoseconds since the OpenGL context was fully realized. Examples -------- Get the current GPU time in seconds:: timeInSeconds = getAbsTimeGPU() * 1e-9 Get the GPU time elapsed:: t0 = getAbsTimeGPU() # some drawing commands here ... t1 = getAbsTimeGPU() timeElapsed = (t1 - t0) * 1e-9 # take difference, convert to seconds """ global QUERY_COUNTER if QUERY_COUNTER is None: GL.glGenQueries(1, ctypes.byref(QUERY_COUNTER)) GL.glQueryCounter(QUERY_COUNTER, GL.GL_TIMESTAMP) params = GL.GLuint64(0) GL.glGetQueryObjectui64v( QUERY_COUNTER, GL.GL_QUERY_RESULT, ctypes.byref(params)) return params.value
# ----------------------------------- # Framebuffer Objects (FBO) Functions # ----------------------------------- # # The functions below simplify the creation and management of Framebuffer # Objects (FBOs). FBO are containers for image buffers (textures or # renderbuffers) frequently used for off-screen rendering. # # FBO descriptor Framebuffer = namedtuple( 'Framebuffer', ['id', 'target', 'userData'] )
[docs]def createFBO(attachments=()): """Create a Framebuffer Object. Parameters ---------- attachments : :obj:`list` or :obj:`tuple` of :obj:`tuple` Optional attachments to initialize the Framebuffer with. Attachments are specified as a list of tuples. Each tuple must contain an attachment point (e.g. GL_COLOR_ATTACHMENT0, GL_DEPTH_ATTACHMENT, etc.) and a buffer descriptor type (Renderbuffer or TexImage2D). If using a combined depth/stencil format such as GL_DEPTH24_STENCIL8, GL_DEPTH_ATTACHMENT and GL_STENCIL_ATTACHMENT must be passed the same buffer. Alternatively, one can use GL_DEPTH_STENCIL_ATTACHMENT instead. If using multisample buffers, all attachment images must use the same number of samples!. As an example, one may specify attachments as 'attachments=(( GL.GL_COLOR_ATTACHMENT0, frameTexture), (GL.GL_DEPTH_STENCIL_ATTACHMENT, depthRenderBuffer))'. Returns ------- Framebuffer Framebuffer descriptor. Notes ----- - All buffers must have the same number of samples. - The 'userData' field of the returned descriptor is a dictionary that can be used to store arbitrary data associated with the FBO. - Framebuffers need a single attachment to be complete. Examples -------- Create an empty framebuffer with no attachments:: fbo = createFBO() # invalid until attachments are added Create a render target with multiple color texture attachments:: colorTex = createTexImage2D(1024,1024) # empty texture depthRb = createRenderbuffer(800,600,internalFormat=GL.GL_DEPTH24_STENCIL8) # attach images GL.glBindFramebuffer(GL.GL_FRAMEBUFFER, fbo.id) attach(GL.GL_COLOR_ATTACHMENT0, colorTex) attach(GL.GL_DEPTH_ATTACHMENT, depthRb) attach(GL.GL_STENCIL_ATTACHMENT, depthRb) # or attach(GL.GL_DEPTH_STENCIL_ATTACHMENT, depthRb) GL.glBindFramebuffer(GL.GL_FRAMEBUFFER, 0) # above is the same as with useFBO(fbo): attach(GL.GL_COLOR_ATTACHMENT0, colorTex) attach(GL.GL_DEPTH_ATTACHMENT, depthRb) attach(GL.GL_STENCIL_ATTACHMENT, depthRb) Examples of userData some custom function might access:: fbo.userData['flags'] = ['left_eye', 'clear_before_use'] Using a depth only texture (for shadow mapping?):: depthTex = createTexImage2D(800, 600, internalFormat=GL.GL_DEPTH_COMPONENT24, pixelFormat=GL.GL_DEPTH_COMPONENT) fbo = createFBO([(GL.GL_DEPTH_ATTACHMENT, depthTex)]) # is valid # discard FBO descriptor, just give me the ID frameBuffer = createFBO().id """ fboId = GL.GLuint() GL.glGenFramebuffers(1, ctypes.byref(fboId)) # create a framebuffer descriptor fboDesc = Framebuffer(fboId, GL.GL_FRAMEBUFFER, dict()) # initial attachments for this framebuffer if attachments: with useFBO(fboDesc): for attachPoint, imageBuffer in attachments: attach(attachPoint, imageBuffer) return fboDesc
[docs]def attach(attachPoint, imageBuffer): """Attach an image to a specified attachment point on the presently bound FBO. Parameters ---------- attachPoint :obj:`int` Attachment point for 'imageBuffer' (e.g. GL.GL_COLOR_ATTACHMENT0). imageBuffer : :obj:`TexImage2D` or :obj:`Renderbuffer` Framebuffer-attachable buffer descriptor. Examples -------- Attach an image to attachment points on the framebuffer:: GL.glBindFramebuffer(GL.GL_FRAMEBUFFER, fbo) attach(GL.GL_COLOR_ATTACHMENT0, colorTex) attach(GL.GL_DEPTH_STENCIL_ATTACHMENT, depthRb) GL.glBindFramebuffer(GL.GL_FRAMEBUFFER, lastBoundFbo) # same as above, but using a context manager with useFBO(fbo): attach(GL.GL_COLOR_ATTACHMENT0, colorTex) attach(GL.GL_DEPTH_STENCIL_ATTACHMENT, depthRb) """ # We should also support binding GL names specified as integers. Right now # you need as descriptor which contains the target and name for the buffer. # if isinstance(imageBuffer, (TexImage2D, TexImage2DMultisample)): GL.glFramebufferTexture2D( GL.GL_FRAMEBUFFER, attachPoint, imageBuffer.target, imageBuffer.id, 0) elif isinstance(imageBuffer, Renderbuffer): GL.glFramebufferRenderbuffer( GL.GL_FRAMEBUFFER, attachPoint, imageBuffer.target, imageBuffer.id)
[docs]def isComplete(): """Check if the currently bound framebuffer is complete. Returns ------- bool `True` if the presently bound FBO is complete. """ return GL.glCheckFramebufferStatus(GL.GL_FRAMEBUFFER) == \ GL.GL_FRAMEBUFFER_COMPLETE
[docs]def deleteFBO(fbo): """Delete a framebuffer. """ GL.glDeleteFramebuffers( 1, fbo.id if isinstance(fbo, Framebuffer) else int(fbo))
[docs]def blitFBO(srcRect, dstRect=None, filter=GL.GL_LINEAR): """Copy a block of pixels between framebuffers via blitting. Read and draw framebuffers must be bound prior to calling this function. Beware, the scissor box and viewport are changed when this is called to dstRect. Parameters ---------- srcRect : :obj:`list` of :obj:`int` List specifying the top-left and bottom-right coordinates of the region to copy from (<X0>, <Y0>, <X1>, <Y1>). dstRect : :obj:`list` of :obj:`int` or :obj:`None` List specifying the top-left and bottom-right coordinates of the region to copy to (<X0>, <Y0>, <X1>, <Y1>). If None, srcRect is used for dstRect. filter : :obj:`int` Interpolation method to use if the image is stretched, default is GL_LINEAR, but can also be GL_NEAREST. Returns ------- None Examples -------- Blitting pixels from on FBO to another:: # bind framebuffer to read pixels from GL.glBindFramebuffer(GL.GL_READ_FRAMEBUFFER, srcFbo) # bind framebuffer to draw pixels to GL.glBindFramebuffer(GL.GL_DRAW_FRAMEBUFFER, dstFbo) gltools.blitFBO((0,0,800,600), (0,0,800,600)) # unbind both read and draw buffers GL.glBindFramebuffer(GL.GL_FRAMEBUFFER, 0) """ # in most cases srcRect and dstRect will be the same. if dstRect is None: dstRect = srcRect # GL.glViewport(*dstRect) # GL.glEnable(GL.GL_SCISSOR_TEST) # GL.glScissor(*dstRect) GL.glBlitFramebuffer(srcRect[0], srcRect[1], srcRect[2], srcRect[3], dstRect[0], dstRect[1], dstRect[2], dstRect[3], GL.GL_COLOR_BUFFER_BIT, # colors only for now filter)
# GL.glDisable(GL.GL_SCISSOR_TEST)
[docs]@contextmanager def useFBO(fbo): """Context manager for Framebuffer Object bindings. This function yields the framebuffer name as an integer. Parameters ---------- fbo :obj:`int` or :obj:`Framebuffer` OpenGL Framebuffer Object name/ID or descriptor. Yields ------- int OpenGL name of the framebuffer bound in the context. Examples -------- Using a framebuffer context manager:: # FBO bound somewhere deep in our code GL.glBindFramebuffer(GL.GL_FRAMEBUFFER, someOtherFBO) ... # create a new FBO, but we have no idea what the currently bound FBO is fbo = createFBO() # use a context to bind attachments with bindFBO(fbo): attach(GL.GL_COLOR_ATTACHMENT0, colorTex) attach(GL.GL_DEPTH_ATTACHMENT, depthRb) attach(GL.GL_STENCIL_ATTACHMENT, depthRb) isComplete = gltools.isComplete() # someOtherFBO is still bound! """ prevFBO = GL.GLint() GL.glGetIntegerv(GL.GL_FRAMEBUFFER_BINDING, ctypes.byref(prevFBO)) toBind = fbo.id if isinstance(fbo, Framebuffer) else int(fbo) GL.glBindFramebuffer(GL.GL_FRAMEBUFFER, toBind) try: yield toBind finally: GL.glBindFramebuffer(GL.GL_FRAMEBUFFER, prevFBO.value)
# ------------------------------ # Renderbuffer Objects Functions # ------------------------------ # # The functions below handle the creation and management of Renderbuffers # Objects. # # Renderbuffer descriptor type Renderbuffer = namedtuple( 'Renderbuffer', ['id', 'target', 'width', 'height', 'internalFormat', 'samples', 'multiSample', # boolean, check if a texture is multisample 'userData'] # dictionary for user defined data )
[docs]def createRenderbuffer(width, height, internalFormat=GL.GL_RGBA8, samples=1): """Create a new Renderbuffer Object with a specified internal format. A multisample storage buffer is created if samples > 1. Renderbuffers contain image data and are optimized for use as render targets. See https://www.khronos.org/opengl/wiki/Renderbuffer_Object for more information. Parameters ---------- width : :obj:`int` Buffer width in pixels. height : :obj:`int` Buffer height in pixels. internalFormat : :obj:`int` Format for renderbuffer data (e.g. GL_RGBA8, GL_DEPTH24_STENCIL8). samples : :obj:`int` Number of samples for multi-sampling, should be >1 and power-of-two. Work with one sample, but will raise a warning. Returns ------- Renderbuffer A descriptor of the created renderbuffer. Notes ----- The 'userData' field of the returned descriptor is a dictionary that can be used to store arbitrary data associated with the buffer. """ width = int(width) height = int(height) # create a new renderbuffer ID rbId = GL.GLuint() GL.glGenRenderbuffers(1, ctypes.byref(rbId)) GL.glBindRenderbuffer(GL.GL_RENDERBUFFER, rbId) if samples > 1: # determine if the 'samples' value is valid maxSamples = getIntegerv(GL.GL_MAX_SAMPLES) if (samples & (samples - 1)) != 0: raise ValueError('Invalid number of samples, must be power-of-two.') elif samples > maxSamples: raise ValueError('Invalid number of samples, must be <{}.'.format( maxSamples)) # create a multisample render buffer storage GL.glRenderbufferStorageMultisample( GL.GL_RENDERBUFFER, samples, internalFormat, width, height) else: GL.glRenderbufferStorage( GL.GL_RENDERBUFFER, internalFormat, width, height) # done, unbind it GL.glBindRenderbuffer(GL.GL_RENDERBUFFER, 0) return Renderbuffer(rbId, GL.GL_RENDERBUFFER, width, height, internalFormat, samples, samples > 1, dict())
[docs]def deleteRenderbuffer(renderBuffer): """Free the resources associated with a renderbuffer. This invalidates the renderbuffer's ID. """ GL.glDeleteRenderbuffers(1, renderBuffer.id)
# ----------------- # Texture Functions # ----------------- # 2D texture descriptor. You can 'wrap' existing texture IDs with TexImage2D to # use them with functions that require that type as input. # class TexImage2D(object): """Descriptor for a 2D texture. This class is used for bookkeeping 2D textures stored in video memory. Information about the texture (eg. `width` and `height`) is available via class attributes. Attributes should never be modified directly. """ __slots__ = ['width', 'height', 'target', '_name', 'level', 'internalFormat', 'pixelFormat', 'dataType', 'unpackAlignment', '_texParams', '_isBound', '_unit', '_texParamsNeedUpdate'] def __init__(self, name=0, target=GL.GL_TEXTURE_2D, width=64, height=64, level=0, internalFormat=GL.GL_RGBA, pixelFormat=GL.GL_RGBA, dataType=GL.GL_FLOAT, unpackAlignment=4, texParams=None): """ Parameters ---------- name : `int` or `GLuint` OpenGL handle for texture. Is `0` if uninitialized. target : :obj:`int` The target texture should only be either GL_TEXTURE_2D or GL_TEXTURE_RECTANGLE. width : :obj:`int` Texture width in pixels. height : :obj:`int` Texture height in pixels. level : :obj:`int` LOD number of the texture, should be 0 if GL_TEXTURE_RECTANGLE is the target. internalFormat : :obj:`int` Internal format for texture data (e.g. GL_RGBA8, GL_R11F_G11F_B10F). pixelFormat : :obj:`int` Pixel data format (e.g. GL_RGBA, GL_DEPTH_STENCIL) dataType : :obj:`int` Data type for pixel data (e.g. GL_FLOAT, GL_UNSIGNED_BYTE). unpackAlignment : :obj:`int` Alignment requirements of each row in memory. Default is 4. texParams : :obj:`list` of :obj:`tuple` of :obj:`int` Optional texture parameters specified as `dict`. These values are passed to `glTexParameteri`. Each tuple must contain a parameter name and value. For example, `texParameters={ GL.GL_TEXTURE_MIN_FILTER: GL.GL_LINEAR, GL.GL_TEXTURE_MAG_FILTER: GL.GL_LINEAR}`. These can be changed and will be updated the next time this instance is passed to :func:`bindTexture`. """ # fields for texture information self.name = name self.width = width self.height = height self.target = target self.level = level self.internalFormat = internalFormat self.pixelFormat = pixelFormat self.dataType = dataType self.unpackAlignment = unpackAlignment self._texParams = {} # set texture parameters if texParams is not None: for key, val in texParams.items(): self._texParams[key] = val # internal data self._isBound = False # True if the texture has been bound self._unit = None # texture unit assigned to this texture self._texParamsNeedUpdate = True # update texture parameters @property def name(self): return self._name @name.setter def name(self, value): if not isinstance(value, GL.GLuint): self._name = GL.GLuint(int(value)) else: self._name = value @property def size(self): """Size of the texture [w, h] in pixels (`int`, `int`).""" return self.width, self.height @property def texParams(self): """Texture parameters.""" self._texParamsNeedUpdate = True return self._texParams @texParams.setter def texParams(self, value): """Texture parameters.""" self._texParamsNeedUpdate = True self._texParams = value
[docs]def createTexImage2D(width, height, target=GL.GL_TEXTURE_2D, level=0, internalFormat=GL.GL_RGBA8, pixelFormat=GL.GL_RGBA, dataType=GL.GL_FLOAT, data=None, unpackAlignment=4, texParams=None): """Create a 2D texture in video memory. This can only create a single 2D texture with targets `GL_TEXTURE_2D` or `GL_TEXTURE_RECTANGLE`. Parameters ---------- width : :obj:`int` Texture width in pixels. height : :obj:`int` Texture height in pixels. target : :obj:`int` The target texture should only be either GL_TEXTURE_2D or GL_TEXTURE_RECTANGLE. level : :obj:`int` LOD number of the texture, should be 0 if GL_TEXTURE_RECTANGLE is the target. internalFormat : :obj:`int` Internal format for texture data (e.g. GL_RGBA8, GL_R11F_G11F_B10F). pixelFormat : :obj:`int` Pixel data format (e.g. GL_RGBA, GL_DEPTH_STENCIL) dataType : :obj:`int` Data type for pixel data (e.g. GL_FLOAT, GL_UNSIGNED_BYTE). data : :obj:`ctypes` or :obj:`None` Ctypes pointer to image data. If None is specified, the texture will be created but pixel data will be uninitialized. unpackAlignment : :obj:`int` Alignment requirements of each row in memory. Default is 4. texParams : :obj:`dict` Optional texture parameters specified as `dict`. These values are passed to `glTexParameteri`. Each tuple must contain a parameter name and value. For example, `texParameters={GL.GL_TEXTURE_MIN_FILTER: GL.GL_LINEAR, GL.GL_TEXTURE_MAG_FILTER: GL.GL_LINEAR}`. Returns ------- TexImage2D A `TexImage2D` descriptor. Notes ----- The 'userData' field of the returned descriptor is a dictionary that can be used to store arbitrary data associated with the texture. Previous textures are unbound after calling 'createTexImage2D'. Examples -------- Creating a texture from an image file:: import pyglet.gl as GL # using Pyglet for now # empty texture textureDesc = createTexImage2D(1024, 1024, internalFormat=GL.GL_RGBA8) # load texture data from an image file using Pillow and NumPy from PIL import Image import numpy as np im = Image.open(imageFile) # 8bpp! im = im.transpose(Image.FLIP_TOP_BOTTOM) # OpenGL origin is at bottom im = im.convert("RGBA") pixelData = np.array(im).ctypes # convert to ctypes! width = pixelData.shape[1] height = pixelData.shape[0] textureDesc = gltools.createTexImage2D( width, height, internalFormat=GL.GL_RGBA, pixelFormat=GL.GL_RGBA, dataType=GL.GL_UNSIGNED_BYTE, data=pixelData, unpackAlignment=1, texParameters=[(GL.GL_TEXTURE_MAG_FILTER, GL.GL_LINEAR), (GL.GL_TEXTURE_MIN_FILTER, GL.GL_LINEAR)]) GL.glBindTexture(GL.GL_TEXTURE_2D, textureDesc.id) """ width = int(width) height = int(height) if width <= 0 or height <= 0: raise ValueError("Invalid image dimensions {} x {}.".format( width, height)) if target == GL.GL_TEXTURE_RECTANGLE: if level != 0: raise ValueError("Invalid level for target GL_TEXTURE_RECTANGLE, " "must be 0.") GL.glEnable(GL.GL_TEXTURE_RECTANGLE) texId = GL.GLuint() GL.glGenTextures(1, ctypes.byref(texId)) GL.glBindTexture(target, texId) GL.glPixelStorei(GL.GL_UNPACK_ALIGNMENT, int(unpackAlignment)) GL.glTexImage2D(target, level, internalFormat, width, height, 0, pixelFormat, dataType, data) # apply texture parameters if texParams is not None: for pname, param in texParams.items(): GL.glTexParameteri(target, pname, param) # new texture descriptor tex = TexImage2D(name=texId, target=target, width=width, height=height, internalFormat=internalFormat, level=level, pixelFormat=pixelFormat, dataType=dataType, unpackAlignment=unpackAlignment, texParams=texParams) tex._texParamsNeedUpdate = False GL.glBindTexture(target, 0) return tex
[docs]def createTexImage2dFromFile(imgFile, transpose=True): """Load an image from file directly into a texture. This is a convenience function to quickly get an image file loaded into a 2D texture. The image is converted to RGBA format. Texture parameters are set for linear interpolation. Parameters ---------- imgFile : str Path to the image file. transpose : bool Flip the image so it appears upright when displayed in OpenGL image coordinates. Returns ------- TexImage2D Texture descriptor. """ im = Image.open(imgFile) # 8bpp! if transpose: im = im.transpose(Image.FLIP_TOP_BOTTOM) # OpenGL origin is at bottom im = im.convert("RGBA") pixelData = np.array(im).ctypes # convert to ctypes! width = pixelData.shape[1] height = pixelData.shape[0] textureDesc = createTexImage2D( width, height, internalFormat=GL.GL_RGBA, pixelFormat=GL.GL_RGBA, dataType=GL.GL_UNSIGNED_BYTE, data=pixelData, unpackAlignment=1, texParams={GL.GL_TEXTURE_MAG_FILTER: GL.GL_LINEAR, GL.GL_TEXTURE_MIN_FILTER: GL.GL_LINEAR}) return textureDesc
class TexCubeMap(object): """Descriptor for a cube map texture.. This class is used for bookkeeping cube maps stored in video memory. Information about the texture (eg. `width` and `height`) is available via class attributes. Attributes should never be modified directly. """ __slots__ = ['width', 'height', 'target', '_name', 'level', 'internalFormat', 'pixelFormat', 'dataType', 'unpackAlignment', '_texParams', '_isBound', '_unit', '_texParamsNeedUpdate'] def __init__(self, name=0, target=GL.GL_TEXTURE_CUBE_MAP, width=64, height=64, level=0, internalFormat=GL.GL_RGBA, pixelFormat=GL.GL_RGBA, dataType=GL.GL_FLOAT, unpackAlignment=4, texParams=None): """ Parameters ---------- name : `int` or `GLuint` OpenGL handle for texture. Is `0` if uninitialized. target : :obj:`int` The target texture should only be `GL_TEXTURE_CUBE_MAP`. width : :obj:`int` Texture width in pixels. height : :obj:`int` Texture height in pixels. level : :obj:`int` LOD number of the texture. internalFormat : :obj:`int` Internal format for texture data (e.g. GL_RGBA8, GL_R11F_G11F_B10F). pixelFormat : :obj:`int` Pixel data format (e.g. GL_RGBA, GL_DEPTH_STENCIL) dataType : :obj:`int` Data type for pixel data (e.g. GL_FLOAT, GL_UNSIGNED_BYTE). unpackAlignment : :obj:`int` Alignment requirements of each row in memory. Default is 4. texParams : :obj:`list` of :obj:`tuple` of :obj:`int` Optional texture parameters specified as `dict`. These values are passed to `glTexParameteri`. Each tuple must contain a parameter name and value. For example, `texParameters={ GL.GL_TEXTURE_MIN_FILTER: GL.GL_LINEAR, GL.GL_TEXTURE_MAG_FILTER: GL.GL_LINEAR}`. These can be changed and will be updated the next time this instance is passed to :func:`bindTexture`. """ # fields for texture information self.name = name self.width = width self.height = height self.target = target self.level = level self.internalFormat = internalFormat self.pixelFormat = pixelFormat self.dataType = dataType self.unpackAlignment = unpackAlignment self._texParams = {} # set texture parameters if texParams is not None: for key, val in texParams.items(): self._texParams[key] = val # internal data self._isBound = False # True if the texture has been bound self._unit = None # texture unit assigned to this texture self._texParamsNeedUpdate = True # update texture parameters @property def name(self): return self._name @name.setter def name(self, value): if not isinstance(value, GL.GLuint): self._name = GL.GLuint(int(value)) else: self._name = value @property def size(self): """Size of a single cubemap face [w, h] in pixels (`int`, `int`).""" return self.width, self.height @property def texParams(self): """Texture parameters.""" self._texParamsNeedUpdate = True return self._texParams @texParams.setter def texParams(self, value): """Texture parameters.""" self._texParamsNeedUpdate = True self._texParams = value
[docs]def createCubeMap(width, height, target=GL.GL_TEXTURE_CUBE_MAP, level=0, internalFormat=GL.GL_RGBA, pixelFormat=GL.GL_RGBA, dataType=GL.GL_UNSIGNED_BYTE, data=None, unpackAlignment=4, texParams=None): """Create a cubemap. Parameters ---------- name : `int` or `GLuint` OpenGL handle for the cube map. Is `0` if uninitialized. target : :obj:`int` The target texture should only be `GL_TEXTURE_CUBE_MAP`. width : :obj:`int` Texture width in pixels. height : :obj:`int` Texture height in pixels. level : :obj:`int` LOD number of the texture. internalFormat : :obj:`int` Internal format for texture data (e.g. GL_RGBA8, GL_R11F_G11F_B10F). pixelFormat : :obj:`int` Pixel data format (e.g. GL_RGBA, GL_DEPTH_STENCIL) dataType : :obj:`int` Data type for pixel data (e.g. GL_FLOAT, GL_UNSIGNED_BYTE). data : list or tuple List of six ctypes pointers to image data for each cubemap face. Image data is assigned to a face by index [+X, -X, +Y, -Y, +Z, -Z]. All images must have the same size as specified by `width` and `height`. unpackAlignment : :obj:`int` Alignment requirements of each row in memory. Default is 4. texParams : :obj:`list` of :obj:`tuple` of :obj:`int` Optional texture parameters specified as `dict`. These values are passed to `glTexParameteri`. Each tuple must contain a parameter name and value. For example, `texParameters={ GL.GL_TEXTURE_MIN_FILTER: GL.GL_LINEAR, GL.GL_TEXTURE_MAG_FILTER: GL.GL_LINEAR}`. These can be changed and will be updated the next time this instance is passed to :func:`bindTexture`. """ texId = GL.GLuint() GL.glGenTextures(1, ctypes.byref(texId)) GL.glBindTexture(target, texId) # create faces of the cube map for face in range(6): GL.glPixelStorei(GL.GL_UNPACK_ALIGNMENT, int(unpackAlignment)) GL.glTexImage2D(GL.GL_TEXTURE_CUBE_MAP_POSITIVE_X + face, level, internalFormat, width, height, 0, pixelFormat, dataType, data[face] if data is not None else data) # apply texture parameters if texParams is not None: for pname, param in texParams.items(): GL.glTexParameteri(target, pname, param) GL.glBindTexture(target, 0) tex = TexCubeMap(name=texId, target=target, width=width, height=height, internalFormat=internalFormat, level=level, pixelFormat=pixelFormat, dataType=dataType, unpackAlignment=unpackAlignment, texParams=texParams) return tex
[docs]def bindTexture(texture, unit=None, enable=True): """Bind a texture. Function binds `texture` to `unit` (if specified). If `unit` is `None`, the texture will be bound but not assigned to a texture unit. Parameters ---------- texture : TexImage2D Texture descriptor to bind. unit : int, optional Texture unit to associated the texture with. enable : bool Enable textures upon binding. """ if not texture._isBound: if enable: GL.glEnable(texture.target) GL.glBindTexture(texture.target, texture.name) texture._isBound = True if unit is not None: texture._unit = unit GL.glActiveTexture(GL.GL_TEXTURE0 + unit) # update texture parameters if they have been accessed (changed?) if texture._texParamsNeedUpdate: for pname, param in texture._texParams.items(): GL.glTexParameteri(texture.target, pname, param) texture._texParamsNeedUpdate = False
[docs]def unbindTexture(texture=None): """Unbind a texture. Parameters ---------- texture : TexImage2D Texture descriptor to unbind. """ if texture._isBound: # set the texture unit if texture._unit is not None: GL.glActiveTexture(GL.GL_TEXTURE0 + texture._unit) texture._unit = None GL.glBindTexture(texture.target, 0) texture._isBound = False GL.glDisable(texture.target) else: raise RuntimeError('Trying to unbind a texture that was not previously' 'bound.')
# Descriptor for 2D mutlisampled texture TexImage2DMultisample = namedtuple( 'TexImage2D', ['id', 'target', 'width', 'height', 'internalFormat', 'samples', 'multisample', 'userData'])
[docs]def createTexImage2DMultisample(width, height, target=GL.GL_TEXTURE_2D_MULTISAMPLE, samples=1, internalFormat=GL.GL_RGBA8, texParameters=()): """Create a 2D multisampled texture. Parameters ---------- width : :obj:`int` Texture width in pixels. height : :obj:`int` Texture height in pixels. target : :obj:`int` The target texture (e.g. GL_TEXTURE_2D_MULTISAMPLE). samples : :obj:`int` Number of samples for multi-sampling, should be >1 and power-of-two. Work with one sample, but will raise a warning. internalFormat : :obj:`int` Internal format for texture data (e.g. GL_RGBA8, GL_R11F_G11F_B10F). texParameters : :obj:`list` of :obj:`tuple` of :obj:`int` Optional texture parameters specified as a list of tuples. These values are passed to 'glTexParameteri'. Each tuple must contain a parameter name and value. For example, texParameters=[(GL.GL_TEXTURE_MIN_FILTER, GL.GL_LINEAR), (GL.GL_TEXTURE_MAG_FILTER, GL.GL_LINEAR)] Returns ------- TexImage2DMultisample A TexImage2DMultisample descriptor. """ width = int(width) height = int(height) if width <= 0 or height <= 0: raise ValueError("Invalid image dimensions {} x {}.".format( width, height)) # determine if the 'samples' value is valid maxSamples = getIntegerv(GL.GL_MAX_SAMPLES) if (samples & (samples - 1)) != 0: raise ValueError('Invalid number of samples, must be power-of-two.') elif samples <= 0 or samples > maxSamples: raise ValueError('Invalid number of samples, must be <{}.'.format( maxSamples)) colorTexId = GL.GLuint() GL.glGenTextures(1, ctypes.byref(colorTexId)) GL.glBindTexture(target, colorTexId) GL.glTexImage2DMultisample( target, samples, internalFormat, width, height, GL.GL_TRUE) # apply texture parameters if texParameters: for pname, param in texParameters: GL.glTexParameteri(target, pname, param) GL.glBindTexture(target, 0) return TexImage2DMultisample(colorTexId, target, width, height, internalFormat, samples, True, dict())
[docs]def deleteTexture(texture): """Free the resources associated with a texture. This invalidates the texture's ID. """ if not texture._isBound: GL.glDeleteTextures(1, texture.name) texture.name = 0 # invalidate else: raise RuntimeError("Attempting to delete texture which is presently " "bound.")
# -------------------------- # Vertex Array Objects (VAO) #
[docs]class VertexArrayInfo(object): """Vertex array object (VAO) descriptor. This class only stores information about the VAO it refers to, it does not contain any actual array data associated with the VAO. Calling :func:`createVAO` returns instances of this class. If `isLegacy` is `True`, attribute binding states are using deprecated (but still supported) pointer definition calls (eg. `glVertexPointer`). This is to ensure backwards compatibility. The keys stored in `activeAttribs` must be `GLenum` types such as `GL_VERTEX_ARRAY`. Parameters ---------- name : int OpenGL handle for the VAO. count : int Number of vertex elements. If `indexBuffer` is not `None`, count corresponds to the number of elements in the index buffer. activeAttribs : dict Attributes and buffers defined as part of this VAO state. Keys are attribute pointer indices or capabilities (ie. GL_VERTEX_ARRAY). Modifying these values will not update the VAO state. indexBuffer : VertexBufferInfo, optional Buffer object for indices. attribDivisors : dict, optional Divisors for each attribute. isLegacy : bool Array pointers were defined using the deprecated OpenGL API. If `True`, the VAO may work with older GLSL shaders versions and the fixed-function pipeline. userData : dict or None, optional Optional user defined data associated with this VAO. """ __slots__ = ['name', 'count', 'activeAttribs', 'indexBuffer', 'isLegacy', 'userData', 'attribDivisors']
[docs] def __init__(self, name=0, count=0, activeAttribs=None, indexBuffer=None, attribDivisors=None, isLegacy=False, userData=None): self.name = name self.activeAttribs = activeAttribs self.count = count self.indexBuffer = indexBuffer self.attribDivisors = attribDivisors self.isLegacy = isLegacy if userData is None: self.userData = {} elif isinstance(userData, dict): self.userData = userData else: raise TypeError('Invalid type for `userData`.')
def __hash__(self): return hash((self.name, self.isLegacy)) def __eq__(self, other): """Equality test between VAO object names.""" return self.name == other.name def __ne__(self, other): """Inequality test between VAO object names.""" return self.name != other.name
[docs]def createVAO(attribBuffers, indexBuffer=None, attribDivisors=None, legacy=False): """Create a Vertex Array object (VAO). VAOs store buffer binding states, reducing CPU overhead when drawing objects with vertex data stored in VBOs. Define vertex attributes within a VAO state by passing a mapping for generic attribute indices and VBO buffers. Parameters ---------- attribBuffers : dict Attributes and associated VBOs to add to the VAO state. Keys are vertex attribute pointer indices, values are VBO descriptors to define. Values can be `tuples` where the first value is the buffer descriptor, the second is the number of attribute components (`int`, either 2, 3 or 4), the third is the offset (`int`), and the last is whether to normalize the array (`bool`). indexBuffer : VertexBufferInfo Optional index buffer. attribDivisors : dict Attribute divisors to set. Keys are vertex attribute pointer indices, values are the number of instances that will pass between updates of an attribute. Setting attribute divisors is only permitted if `legacy` is `False`. legacy : bool, optional Use legacy attribute pointer functions when setting the VAO state. This is for compatibility with older GL implementations. Key specified to `attribBuffers` must be `GLenum` types such as `GL_VERTEX_ARRAY` to indicate the capability to use. Examples -------- Create a vertex array object and enable buffer states within it:: vao = createVAO({0: vertexPos, 1: texCoords, 2: vertexNormals}) Using an interleaved vertex buffer, all attributes are in the same buffer (`vertexAttr`). We need to specify offsets for each attribute by passing a buffer in a `tuple` with the second value specifying the offset:: # buffer with interleaved layout `00011222` per-attribute vao = createVAO( {0: (vertexAttr, 3), # size 3, offset 0 1: (vertexAttr, 2, 3), # size 2, offset 3 2: (vertexAttr, 3, 5, True)}) # size 3, offset 5, normalize You can mix interleaved and single-use buffers:: vao = createVAO( {0: (vertexAttr, 3, 0), 1: (vertexAttr, 3, 3), 2: vertexColors}) Specifying an optional index array, this is used for indexed drawing of primitives:: vao = createVAO({0: vertexPos}, indexBuffer=indices) The returned `VertexArrayInfo` instance will have attribute ``isIndexed==True``. Drawing vertex arrays using a VAO, will use the `indexBuffer` if available:: # draw the array drawVAO(vao, mode=GL.GL_TRIANGLES) Use legacy attribute pointer bindings when building a VAO for compatibility with the fixed-function pipeline and older GLSL versions:: attribBuffers = {GL_VERTEX_ARRAY: vertexPos, GL_NORMAL_ARRAY: normals} vao = createVAO(attribBuffers, legacy=True) If you wish to used instanced drawing, you can specify attribute divisors this way:: vao = createVAO( {0: (vertexAttr, 3, 0), 1: (vertexAttr, 3, 3), 2: vertexColors}, attribDivisors={2: 1}) """ if not attribBuffers: # in case an empty list is passed raise ValueError("No buffers specified.") # create a vertex buffer ID vaoId = GL.GLuint() GL.glGenVertexArrays(1, ctypes.byref(vaoId)) GL.glBindVertexArray(vaoId) # add attribute pointers activeAttribs = {} bufferIndices = [] for i, buffer in attribBuffers.items(): if isinstance(buffer, (list, tuple,)): if len(buffer) == 1: buffer = buffer[0] # size 1 tuple or list eg. (buffer,) size = buffer.shape[1] offset = 0 normalize = False elif len(buffer) == 2: buffer, size = buffer offset = 0 normalize = False elif len(buffer) == 3: buffer, size, offset = buffer normalize = False elif len(buffer) == 4: buffer, size, offset, normalize = buffer else: raise ValueError('Invalid attribute values.') else: size = buffer.shape[1] offset = 0 normalize = False enableVertexAttribArray(i, legacy) setVertexAttribPointer(i, buffer, size, offset, normalize, legacy) activeAttribs[i] = buffer bufferIndices.append(buffer.shape[0]) # bind the EBO if available if indexBuffer is not None: if indexBuffer.target == GL.GL_ELEMENT_ARRAY_BUFFER: GL.glBindBuffer(GL.GL_ELEMENT_ARRAY_BUFFER, indexBuffer.name) if len(indexBuffer.shape) > 1: count = indexBuffer.shape[0] * indexBuffer.shape[1] else: count = indexBuffer.shape[0] else: raise ValueError( 'Index buffer does not have target `GL_ELEMENT_ARRAY_BUFFER`.') else: if bufferIndices.count(bufferIndices[0]) != len(bufferIndices): warnings.warn( 'Input arrays have unequal number of rows, using shortest for ' '`count`.') count = min(bufferIndices) else: count = bufferIndices[0] # set attribute divisors if attribDivisors is not None: if legacy is True: raise ValueError( 'Cannot set attribute divisors when `legacy` is `True.') for key, val in attribDivisors.items(): GL.glVertexAttribDivisor(key, val) GL.glBindVertexArray(0) return VertexArrayInfo(vaoId.value, count, activeAttribs, indexBuffer, attribDivisors, legacy)
[docs]def drawVAO(vao, mode=GL.GL_TRIANGLES, start=0, count=None, instanceCount=None, flush=False): """Draw a vertex array object. Uses `glDrawArrays` or `glDrawElements` if `instanceCount` is `None`, or else `glDrawArraysInstanced` or `glDrawElementsInstanced` is used. Parameters ---------- vao : VertexArrayObject Vertex Array Object (VAO) to draw. mode : int, optional Drawing mode to use (e.g. GL_TRIANGLES, GL_QUADS, GL_POINTS, etc.) start : int, optional Starting index for array elements. Default is `0` which is the beginning of the array. count : int, optional Number of indices to draw from `start`. Must not exceed `vao.count` - `start`. instanceCount : int or None Number of instances to draw. If >0 and not `None`, instanced drawing will be used. flush : bool, optional Flush queued drawing commands before returning. Examples -------- Creating a VAO and drawing it:: # draw the VAO, renders the mesh drawVAO(vaoDesc, GL.GL_TRIANGLES) """ # draw the array GL.glBindVertexArray(vao.name) if count is None: count = vao.count else: if count > vao.count - start: raise ValueError( "Value of `count` cannot exceed `{}`.".format( vao.count - start)) if vao.indexBuffer is not None: if instanceCount is None: GL.glDrawElements(mode, count, vao.indexBuffer.dataType, start) else: GL.glDrawElementsInstanced(mode, count, vao.indexBuffer.dataType, start, instanceCount) else: if instanceCount is None: GL.glDrawArrays(mode, start, count) else: GL.glDrawArraysInstanced(mode, start, count, instanceCount) if flush: GL.glFlush() # reset GL.glBindVertexArray(0)
[docs]def deleteVAO(vao): """Delete a Vertex Array Object (VAO). This does not delete array buffers bound to the VAO. Parameters ---------- vao : VertexArrayInfo VAO to delete. All fields in the descriptor except `userData` will be reset. """ if isinstance(vao, VertexArrayInfo): if vao.name: GL.glDeleteVertexArrays(1, GL.GLuint(vao.name)) vao.name = 0 vao.isLegacy = False vao.indexBuffer = None vao.activeAttribs = {} vao.count = 0
# --------------------------- # Vertex Buffer Objects (VBO) #
[docs]class VertexBufferInfo(object): """Vertex buffer object (VBO) descriptor. This class only stores information about the VBO it refers to, it does not contain any actual array data associated with the VBO. Calling :func:`createVBO` returns instances of this class. It is recommended to use `gltools` functions :func:`bindVBO`, :func:`unbindVBO`, :func:`mapBuffer`, etc. when working with these objects. Parameters ---------- name : GLuint or int OpenGL handle for the buffer. target : GLenum or int, optional Target used when binding the buffer (e.g. `GL_VERTEX_ARRAY` or `GL_ELEMENT_ARRAY_BUFFER`). Default is `GL_VERTEX_ARRAY`) usage : GLenum or int, optional Usage type for the array (i.e. `GL_STATIC_DRAW`). dataType : Glenum, optional Data type of array. Default is `GL_FLOAT`. size : int, optional Size of the buffer in bytes. stride : int, optional Number of bytes between adjacent attributes. If `0`, values are assumed to be tightly packed. shape : tuple or list, optional Shape of the array used to create this VBO. userData : dict, optional Optional user defined data associated with the VBO. If `None`, `userData` will be initialized as an empty dictionary. """ __slots__ = ['name', 'target', 'usage', 'dataType', 'size', 'stride', 'shape', 'userData']
[docs] def __init__(self, name=0, target=GL.GL_ARRAY_BUFFER, usage=GL.GL_STATIC_DRAW, dataType=GL.GL_FLOAT, size=0, stride=0, shape=(0,), userData=None): self.name = name self.target = target self.usage = usage self.dataType = dataType self.size = size self.stride = stride self.shape = shape if userData is None: self.userData = {} elif isinstance(userData, dict): self.userData = userData else: raise TypeError('Invalid type for `userData`.')
def __hash__(self): return hash((self.name, self.target, self.dataType, self.usage, self.size, self.shape)) def __eq__(self, other): """Equality test between VBO object names.""" return self.name == other.name def __ne__(self, other): """Inequality test between VBO object names.""" return self.name != other.name @property def hasBuffer(self): """Check if the VBO assigned to `name` is a buffer.""" if self.name != 0 and GL.glIsBuffer(self.name): return True return False @property def isIndex(self): """`True` if the buffer referred to by this object is an index array.""" if self.name != 0 and GL.glIsBuffer(self.name): return self.target == GL.GL_ELEMENT_ARRAY_BUFFER return False def validate(self): """Check if the data contained in this descriptor matches what is actually present in the OpenGL state. Returns ------- bool `True` if the information contained in this descriptor matches the OpenGL state. """ # fail automatically if these conditions are true if self.name == 0 or GL.glIsBuffer(self.name) != GL.GL_TRUE: return False if self.target == GL.GL_ARRAY_BUFFER: bindTarget = GL.GL_VERTEX_ARRAY_BUFFER_BINDING elif self.target == GL.GL_ELEMENT_ARRAY_BUFFER: bindTarget = GL.GL_ELEMENT_ARRAY_BUFFER_BINDING else: raise ValueError( 'Invalid `target` type, must be `GL_ARRAY_BUFFER` or ' '`GL_ELEMENT_ARRAY_BUFFER`.') # get current binding so we don't disturb the current state currentVBO = GL.GLint() GL.glGetIntegerv(bindTarget, ctypes.byref(currentVBO)) # bind buffer at name to validate GL.glBindBuffer(self.target, self.name) # get buffer parameters actualSize = GL.GLint() GL.glGetBufferParameteriv( self.target, GL.GL_BUFFER_SIZE, ctypes.byref(actualSize)) actualUsage = GL.GLint() GL.glGetBufferParameteriv( self.target, GL.GL_BUFFER_USAGE, ctypes.byref(actualUsage)) # check values against those in this object isValid = False if self.usage == actualUsage.value and self.size == actualSize.value: isValid = True # return to the original binding GL.glBindBuffer(self.target, currentVBO.value) return isValid
[docs]def createVBO(data, target=GL.GL_ARRAY_BUFFER, dataType=GL.GL_FLOAT, usage=GL.GL_STATIC_DRAW): """Create an array buffer object (VBO). Creates a VBO using input data, usually as a `ndarray` or `list`. Attributes common to one vertex should occupy a single row of the `data` array. Parameters ---------- data : array_like A 2D array of values to write to the array buffer. The data type of the VBO is inferred by the type of the array. If the input is a Python `list` or `tuple` type, the data type of the array will be `GL_FLOAT`. target : :obj:`int` Target used when binding the buffer (e.g. `GL_VERTEX_ARRAY` or `GL_ELEMENT_ARRAY_BUFFER`). Default is `GL_VERTEX_ARRAY`. dataType : Glenum, optional Data type of array. Input data will be recast to an appropriate type if necessary. Default is `GL_FLOAT`. usage : GLenum or int, optional Usage type for the array (i.e. `GL_STATIC_DRAW`). Returns ------- VertexBufferInfo A descriptor with vertex buffer information. Examples -------- Creating a vertex buffer object with vertex data:: # vertices of a triangle verts = [[ 1.0, 1.0, 0.0], # v0 [ 0.0, -1.0, 0.0], # v1 [-1.0, 1.0, 0.0]] # v2 # load vertices to graphics device, return a descriptor vboDesc = createVBO(verts) Drawing triangles or quads using vertex buffer data:: nIndices, vSize = vboDesc.shape # element size bindVBO(vboDesc) setVertexAttribPointer( GL_VERTEX_ARRAY, vSize, vboDesc.dataType, legacy=True) enableVertexAttribArray(GL_VERTEX_ARRAY, legacy=True) if vSize == 3: drawMode = GL_TRIANGLES elif vSize == 4: drawMode = GL_QUADS glDrawArrays(drawMode, 0, nIndices) glFlush() disableVertexAttribArray(GL_VERTEX_ARRAY, legacy=True) unbindVBO() Custom data can be associated with this vertex buffer by specifying `userData`:: myVBO = createVBO(data) myVBO.userData['startIdx'] = 14 # first index to draw with # use it later nIndices, vSize = vboDesc.shape # element size startIdx = myVBO.userData['startIdx'] endIdx = nIndices - startIdx glDrawArrays(GL_TRIANGLES, startIdx, endIdx) glFlush() """ # build input array npType, glType = GL_COMPAT_TYPES[dataType] data = np.asarray(data, dtype=npType) # get buffer size and pointer bufferSize = data.size * ctypes.sizeof(glType) if data.ndim > 1: bufferStride = data.shape[1] * ctypes.sizeof(glType) else: bufferStride = 0 bufferPtr = data.ctypes.data_as(ctypes.POINTER(glType)) # create a vertex buffer ID bufferName = GL.GLuint() GL.glGenBuffers(1, ctypes.byref(bufferName)) # bind and upload GL.glBindBuffer(target, bufferName) GL.glBufferData(target, bufferSize, bufferPtr, usage) GL.glBindBuffer(target, 0) vboInfo = VertexBufferInfo( bufferName, target, usage, dataType, bufferSize, bufferStride, data.shape) # leave userData empty return vboInfo
[docs]def bindVBO(vbo): """Bind a VBO to the current GL state. Parameters ---------- vbo : VertexBufferInfo VBO descriptor to bind. Returns ------- bool `True` is the binding state was changed. Returns `False` if the state was not changed due to the buffer already being bound. """ if isinstance(vbo, VertexBufferInfo): GL.glBindBuffer(vbo.target, vbo.name) else: raise TypeError('Specified `vbo` is not at `VertexBufferInfo`.')
[docs]def unbindVBO(vbo): """Unbind a vertex buffer object (VBO). Parameters ---------- vbo : VertexBufferInfo VBO descriptor to unbind. """ if isinstance(vbo, VertexBufferInfo): GL.glBindBuffer(vbo.target, 0) else: raise TypeError('Specified `vbo` is not at `VertexBufferInfo`.')
[docs]def mapBuffer(vbo, start=0, length=None, read=True, write=True, noSync=False): """Map a vertex buffer object to client memory. This allows you to modify its contents. If planning to update VBO vertex data, make sure the VBO `usage` types are `GL_DYNAMIC_*` or `GL_STREAM_*` or else serious performance issues may arise. Warnings -------- Modifying buffer data must be done carefully, or else system stability may be affected. Do not use the returned view `ndarray` outside of successive :func:`mapBuffer` and :func:`unmapBuffer` calls. Do not use the mapped buffer for rendering until after :func:`unmapBuffer` is called. Parameters ---------- vbo : VertexBufferInfo Vertex buffer to map to client memory. start : int Initial index of the sub-range of the buffer to modify. length : int or None Number of elements of the sub-array to map from `offset`. If `None`, all elements to from `offset` to the end of the array are mapped. read : bool, optional Allow data to be read from the buffer (sets `GL_MAP_READ_BIT`). This is ignored if `noSync` is `True`. write : bool, optional Allow data to be written to the buffer (sets `GL_MAP_WRITE_BIT`). noSync : bool, optional If `True`, GL will not wait until the buffer is free (i.e. not being processed by the GPU) to map it (sets `GL_MAP_UNSYNCHRONIZED_BIT`). The contents of the previous storage buffer are discarded and the driver returns a new one. This prevents the CPU from stalling until the buffer is available. Returns ------- ndarray View of the data. The type of the returned array is one which best matches the data type of the buffer. Examples -------- Map a buffer and edit it:: arr = mapBuffer(vbo) arr[:, :] += 2.0 # add 2 to all values unmapBuffer(vbo) # call when done # Don't ever modify `arr` after calling `unmapBuffer`. Delete it if # necessary to prevent it form being used. del arr Modify a sub-range of data by specifying `start` and `length`, indices correspond to values, not byte offsets:: arr = mapBuffer(vbo, start=12, end=24) arr[:, :] *= 10.0 unmapBuffer(vbo) """ npType, glType = GL_COMPAT_TYPES[vbo.dataType] start *= ctypes.sizeof(glType) if length is None: length = vbo.size else: length *= ctypes.sizeof(glType) accessFlags = GL.GL_NONE if noSync: # if set, don't set GL_MAP_READ_BIT accessFlags |= GL.GL_MAP_UNSYNCHRONIZED_BIT elif read: accessFlags |= GL.GL_MAP_READ_BIT if write: accessFlags |= GL.GL_MAP_WRITE_BIT bindVBO(vbo) # bind the buffer for mapping # get pointer to the buffer bufferPtr = GL.glMapBufferRange( vbo.target, GL.GLintptr(start), GL.GLintptr(length), accessFlags) bufferArray = np.ctypeslib.as_array( ctypes.cast(bufferPtr, ctypes.POINTER(glType)), shape=vbo.shape) return bufferArray
[docs]def unmapBuffer(vbo): """Unmap a previously mapped buffer. Must be called after :func:`mapBuffer` is called and before any drawing operations which use the buffer are called. Failing to call this before using the buffer could result in a system error. Parameters ---------- vbo : VertexBufferInfo Vertex buffer descriptor. Returns ------- bool `True` if the buffer has been successfully modified. If `False`, the data was corrupted for some reason and needs to be resubmitted. """ return GL.glUnmapBuffer(vbo.target) == GL.GL_TRUE
[docs]def deleteVBO(vbo): """Delete a vertex buffer object (VBO). Parameters ---------- vbo : VertexBufferInfo Descriptor of VBO to delete. """ if GL.glIsBuffer(vbo.name): GL.glDeleteBuffers(1, vbo.name) vbo.name = GL.GLuint(0)
[docs]def setVertexAttribPointer(index, vbo, size=None, offset=0, normalize=False, legacy=False): """Define an array of vertex attribute data with a VBO descriptor. In modern OpenGL implementations, attributes are 'generic', where an attribute pointer index does not correspond to any special vertex property. Usually the usage for an attribute is defined in the shader program. It is recommended that shader programs define attributes using the `layout` parameters:: layout (location = 0) in vec3 position; layout (location = 1) in vec2 texCoord; layout (location = 2) in vec3 normal; Setting attribute pointers can be done like this:: setVertexAttribPointer(0, posVbo) setVertexAttribPointer(1, texVbo) setVertexAttribPointer(2, normVbo) For compatibility with older OpenGL specifications, some drivers will alias vertex pointers unless they are explicitly defined in the shader. This allows VAOs the be used with the fixed-function pipeline or older GLSL versions. On nVidia graphics drivers (and maybe others), the following attribute pointers indices are aliased with reserved GLSL names: * gl_Vertex - 0 * gl_Normal - 2 * gl_Color - 3 * gl_SecondaryColor - 4 * gl_FogCoord - 5 * gl_MultiTexCoord0 - 8 * gl_MultiTexCoord1 - 9 * gl_MultiTexCoord2 - 10 * gl_MultiTexCoord3 - 11 * gl_MultiTexCoord4 - 12 * gl_MultiTexCoord5 - 13 * gl_MultiTexCoord6 - 14 * gl_MultiTexCoord7 - 15 Specifying `legacy` as `True` will allow for old-style pointer definitions. You must specify the capability as a `GLenum` associated with the pointer in this case:: setVertexAttribPointer(GL_VERTEX_ARRAY, posVbo, legacy=True) setVertexAttribPointer(GL_TEXTURE_COORD_ARRAY, texVbo, legacy=True) setVertexAttribPointer(GL_NORMAL_ARRAY, normVbo, legacy=True) Parameters ---------- index : int Index of the attribute to modify. If `legacy=True`, this value should be a `GLenum` type corresponding to the capability to bind the buffer to, such as `GL_VERTEX_ARRAY`, `GL_TEXTURE_COORD_ARRAY`, `GL_NORMAL_ARRAY`, etc. vbo : VertexBufferInfo VBO descriptor. size : int, optional Number of components per vertex attribute, can be either 1, 2, 3, or 4. If `None` is specified, the component size will be inferred from the `shape` of the VBO. You must specify this value if the VBO is interleaved. offset : int, optional Starting index of the attribute in the buffer. normalize : bool, optional Normalize fixed-point format values when accessed. legacy : bool, optional Use legacy vertex attributes (ie. `GL_VERTEX_ARRAY`, `GL_TEXTURE_COORD_ARRAY`, etc.) for backwards compatibility. Examples -------- Define a generic attribute from a vertex buffer descriptor:: # set the vertex location attribute setVertexAttribPointer(0, vboDesc) # 0 is vertex in our shader GL.glColor3f(1.0, 0.0, 0.0) # red triangle # draw the triangle nIndices, vSize = vboDesc.shape # element size GL.glDrawArrays(GL.GL_TRIANGLES, 0, nIndices) If our VBO has interleaved attributes, we can specify `offset` to account for that:: # define interleaved vertex attributes # | Position | Texture | Normals | vQuad = [[ -1.0, -1.0, 0.0, 0.0, 0.0, 0.0, 0.0, 1.0], # v0 [ -1.0, 1.0, 0.0, 0.0, 0.0, 0.0, 0.0, 1.0], # v1 [ 1.0, 1.0, 0.0, 0.0, 1.0, 0.0, 0.0, 1.0], # v2 [ 1.0, -1.0, 0.0, 0.0, 1.0, 0.0, 0.0, 1.0]] # v3 # create a VBO with interleaved attributes vboInterleaved = createVBO(np.asarray(vQuad, dtype=np.float32)) # ... before rendering, set the attribute pointers GL.glBindBuffer(vboInterleaved.target, vboInterleaved.name) gltools.setVertexAttribPointer( 0, vboInterleaved, size=3, offset=0) # vertex pointer gltools.setVertexAttribPointer( 8, vboInterleaved, size=2, offset=3) # texture pointer gltools.setVertexAttribPointer( 3, vboInterleaved, size=3, offset=5) # normals pointer # Note, we specified `bind=False` since we are managing the binding # state. It is recommended that you do this when setting up interleaved # buffers to avoid re-binding the same buffer. # draw red, full screen quad GL.glColor3f(1.0, 0.0, 0.0) GL.glDrawArrays(GL.GL_QUADS, 0, vboInterleaved.shape[1]) # call these when done if `enable=True` gltools.disableVertexAttribArray(0) gltools.disableVertexAttribArray(8) gltools.disableVertexAttribArray(1) # unbind the buffer GL.glBindBuffer(vboInterleaved.target, 0) """ if vbo.target != GL.GL_ARRAY_BUFFER: raise ValueError('VBO must have `target` type `GL_ARRAY_BUFFER`.') _, glType = GL_COMPAT_TYPES[vbo.dataType] if size is None: size = vbo.shape[1] offset *= ctypes.sizeof(glType) bindVBO(vbo) if not legacy: GL.glEnableVertexAttribArray(index) GL.glVertexAttribPointer( index, size, vbo.dataType, GL.GL_TRUE if normalize else GL.GL_FALSE, vbo.stride, offset) else: GL.glEnableClientState(index) if index == GL.GL_VERTEX_ARRAY: GL.glVertexPointer(size, vbo.dataType, vbo.stride, offset) elif index == GL.GL_NORMAL_ARRAY: GL.glNormalPointer(vbo.dataType, vbo.stride, offset) elif index == GL.GL_TEXTURE_COORD_ARRAY: GL.glTexCoordPointer(size, vbo.dataType, vbo.stride, offset) elif index == GL.GL_COLOR_ARRAY: GL.glColorPointer(size, vbo.dataType, vbo.stride, offset) elif index == GL.GL_SECONDARY_COLOR_ARRAY: GL.glSecondaryColorPointer(size, vbo.dataType, vbo.stride, offset) elif index == GL.GL_FOG_COORD_ARRAY: GL.glFogCoordPointer(vbo.dataType, vbo.stride, offset) else: raise ValueError('Invalid `index` enum specified.') unbindVBO(vbo)
[docs]def enableVertexAttribArray(index, legacy=False): """Enable a vertex attribute array. Attributes will be used for use by subsequent draw operations. Be sure to call :func:`disableVertexAttribArray` on the same attribute to prevent currently enabled attributes from affecting later rendering. Parameters ---------- index : int Index of the attribute to enable. If `legacy=True`, this value should be a `GLenum` type corresponding to the capability to bind the buffer to, such as `GL_VERTEX_ARRAY`, `GL_TEXTURE_COORD_ARRAY`, `GL_NORMAL_ARRAY`, etc. legacy : bool, optional Use legacy vertex attributes (ie. `GL_VERTEX_ARRAY`, `GL_TEXTURE_COORD_ARRAY`, etc.) for backwards compatibility. """ if not legacy: GL.glEnableVertexAttribArray(index) else: GL.glEnableClientState(index)
[docs]def disableVertexAttribArray(index, legacy=False): """Disable a vertex attribute array. Parameters ---------- index : int Index of the attribute to enable. If `legacy=True`, this value should be a `GLenum` type corresponding to the capability to bind the buffer to, such as `GL_VERTEX_ARRAY`, `GL_TEXTURE_COORD_ARRAY`, `GL_NORMAL_ARRAY`, etc. legacy : bool, optional Use legacy vertex attributes (ie. `GL_VERTEX_ARRAY`, `GL_TEXTURE_COORD_ARRAY`, etc.) for backwards compatibility. """ if not legacy: GL.glDisableVertexAttribArray(index) else: GL.glDisableClientState(index)
# ------------------------- # Material Helper Functions # ------------------------- # # Materials affect the appearance of rendered faces. These helper functions and # datatypes simplify the creation of materials for rendering stimuli. # Material = namedtuple('Material', ['face', 'params', 'textures', 'userData'])
[docs]def createMaterial(params=(), textures=(), face=GL.GL_FRONT_AND_BACK): """Create a new material. Parameters ---------- params : :obj:`list` of :obj:`tuple`, optional List of material modes and values. Each mode is assigned a value as (mode, color). Modes can be GL_AMBIENT, GL_DIFFUSE, GL_SPECULAR, GL_EMISSION, GL_SHININESS or GL_AMBIENT_AND_DIFFUSE. Colors must be a tuple of 4 floats which specify reflectance values for each RGBA component. The value of GL_SHININESS should be a single float. If no values are specified, an empty material will be created. textures :obj:`list` of :obj:`tuple`, optional List of texture units and TexImage2D descriptors. These will be written to the 'textures' field of the returned descriptor. For example, [(GL.GL_TEXTURE0, texDesc0), (GL.GL_TEXTURE1, texDesc1)]. The number of texture units per-material is GL_MAX_COMBINED_TEXTURE_IMAGE_UNITS. face : :obj:`int`, optional Faces to apply material to. Values can be GL_FRONT_AND_BACK, GL_FRONT and GL_BACK. The default is GL_FRONT_AND_BACK. Returns ------- Material A descriptor with material properties. Examples -------- Creating a new material with given properties:: # The values for the material below can be found at # http://devernay.free.fr/cours/opengl/materials.html # create a gold material gold = createMaterial([ (GL.GL_AMBIENT, (0.24725, 0.19950, 0.07450, 1.0)), (GL.GL_DIFFUSE, (0.75164, 0.60648, 0.22648, 1.0)), (GL.GL_SPECULAR, (0.628281, 0.555802, 0.366065, 1.0)), (GL.GL_SHININESS, 0.4 * 128.0)]) Use the material when drawing:: useMaterial(gold) drawVAO( ... ) # all meshes will be gold useMaterial(None) # turn off material when done Create a red plastic material, but define reflectance and shine later:: red_plastic = createMaterial() # you need to convert values to ctypes! red_plastic.values[GL_AMBIENT] = (GLfloat * 4)(0.0, 0.0, 0.0, 1.0) red_plastic.values[GL_DIFFUSE] = (GLfloat * 4)(0.5, 0.0, 0.0, 1.0) red_plastic.values[GL_SPECULAR] = (GLfloat * 4)(0.7, 0.6, 0.6, 1.0) red_plastic.values[GL_SHININESS] = 0.25 * 128.0 # set and draw useMaterial(red_plastic) drawVertexbuffers( ... ) # all meshes will be red plastic useMaterial(None) """ # setup material mode/value slots matDesc = Material( face, {mode: None for mode in ( GL.GL_AMBIENT, GL.GL_DIFFUSE, GL.GL_SPECULAR, GL.GL_EMISSION, GL.GL_SHININESS)}, dict(), dict()) if params: for mode, param in params: matDesc.params[mode] = \ (GL.GLfloat * 4)(*param) \ if mode != GL.GL_SHININESS else GL.GLfloat(param) if textures: maxTexUnits = getIntegerv(GL.GL_MAX_COMBINED_TEXTURE_IMAGE_UNITS) for unit, texDesc in textures: if unit <= GL.GL_TEXTURE0 + (maxTexUnits - 1): matDesc.textures[unit] = texDesc else: raise ValueError("Invalid texture unit enum.") return matDesc
class SimpleMaterial(object): """Class representing a simple material. This class stores material information to modify the appearance of drawn primitives with respect to lighting, such as color (diffuse, specular, ambient, and emission), shininess, and textures. Simple materials are intended to work with features supported by the fixed-function OpenGL pipeline. """ def __init__(self, win=None, diffuseColor=(.5, .5, .5), specularColor=(-1., -1., -1.), ambientColor=(-1., -1., -1.), emissionColor=(-1., -1., -1.), shininess=10.0, colorSpace='rgb', diffuseTexture=None, specularTexture=None, opacity=1.0, contrast=1.0, face='front', useShaders=False): """ Parameters ---------- win : `~psychopy.visual.Window` or `None` Window this material is associated with, required for shaders and some color space conversions. diffuseColor : array_like Diffuse material color (r, g, b, a) with values between 0.0 and 1.0. specularColor : array_like Specular material color (r, g, b, a) with values between 0.0 and 1.0. ambientColor : array_like Ambient material color (r, g, b, a) with values between 0.0 and 1.0. emissionColor : array_like Emission material color (r, g, b, a) with values between 0.0 and 1.0. shininess : float Material shininess, usually ranges from 0.0 to 128.0. colorSpace : float Color space for `diffuseColor`, `specularColor`, `ambientColor`, and `emissionColor`. diffuseTexture : TexImage2D specularTexture : TexImage2D opacity : float Opacity of the material. Ranges from 0.0 to 1.0 where 1.0 is fully opaque. contrast : float Contrast of the material colors. face : str Face to apply material to. Values are `front`, `back` or `both`. textures : dict, optional Texture maps associated with this material. Textures are specified as a list. The index of textures in the list will be used to set the corresponding texture unit they are bound to. useShaders : bool Use per-pixel lighting when rendering this stimulus. By default, Blinn-Phong shading will be used. """ self.win = win self._diffuseColor = np.zeros((3,), np.float32) self._specularColor = np.zeros((3,), np.float32) self._ambientColor = np.zeros((3,), np.float32) self._emissionColor = np.zeros((3,), np.float32) self._shininess = float(shininess) # internal RGB values post colorspace conversion self._diffuseRGB = np.array((0., 0., 0., 1.), np.float32) self._specularRGB = np.array((0., 0., 0., 1.), np.float32) self._ambientRGB = np.array((0., 0., 0., 1.), np.float32) self._emissionRGB = np.array((0., 0., 0., 1.), np.float32) # which faces to apply the material if face == 'front': self._face = GL.GL_FRONT elif face == 'back': self._face = GL.GL_BACK elif face == 'both': self._face = GL.GL_FRONT_AND_BACK else: raise ValueError("Invalid `face` specified, must be 'front', " "'back' or 'both'.") self.colorSpace = colorSpace self.opacity = opacity self.contrast = contrast self.diffuseColor = diffuseColor self.specularColor = specularColor self.ambientColor = ambientColor self.emissionColor = emissionColor self._diffuseTexture = diffuseTexture self._normalTexture = None self._useTextures = False # keeps track if textures are being used self._useShaders = useShaders @property def diffuseTexture(self): """Diffuse color of the material.""" return self._diffuseTexture @diffuseTexture.setter def diffuseTexture(self, value): self._diffuseTexture = value @property def diffuseColor(self): """Diffuse color of the material.""" return self._diffuseColor @diffuseColor.setter def diffuseColor(self, value): self._diffuseColor = np.asarray(value, np.float32) setColor(self, value, colorSpace=self.colorSpace, operation=None, rgbAttrib='diffuseRGB', colorAttrib='diffuseColor', colorSpaceAttrib='colorSpace') @property def diffuseRGB(self): """Diffuse color of the material.""" return self._diffuseRGB[:3] @diffuseRGB.setter def diffuseRGB(self, value): # make sure the color we got is 32-bit float self._diffuseRGB = np.zeros((4,), np.float32) self._diffuseRGB[:3] = (value * self.contrast + 1) / 2.0 self._diffuseRGB[3] = self.opacity @property def specularColor(self): """Specular color of the material.""" return self._specularColor @specularColor.setter def specularColor(self, value): self._specularColor = np.asarray(value, np.float32) setColor(self, value, colorSpace=self.colorSpace, operation=None, rgbAttrib='specularRGB', colorAttrib='specularColor', colorSpaceAttrib='colorSpace') @property def specularRGB(self): """Diffuse color of the material.""" return self._specularRGB[:3] @specularRGB.setter def specularRGB(self, value): # make sure the color we got is 32-bit float self._specularRGB = np.zeros((4,), np.float32) self._specularRGB[:3] = (value * self.contrast + 1) / 2.0 self._specularRGB[3] = self.opacity @property def ambientColor(self): """Ambient color of the material.""" return self._ambientColor @ambientColor.setter def ambientColor(self, value): self._ambientColor = np.asarray(value, np.float32) setColor(self, value, colorSpace=self.colorSpace, operation=None, rgbAttrib='ambientRGB', colorAttrib='ambientColor', colorSpaceAttrib='colorSpace') @property def ambientRGB(self): """Diffuse color of the material.""" return self._ambientRGB[:3] @ambientRGB.setter def ambientRGB(self, value): # make sure the color we got is 32-bit float self._ambientRGB = np.zeros((4,), np.float32) self._ambientRGB[:3] = (value * self.contrast + 1) / 2.0 self._ambientRGB[3] = self.opacity @property def emissionColor(self): """Emission color of the material.""" return self._emissionColor @emissionColor.setter def emissionColor(self, value): self._emissionColor = np.asarray(value, np.float32) setColor(self, value, colorSpace=self.colorSpace, operation=None, rgbAttrib='emissionRGB', colorAttrib='emissionColor', colorSpaceAttrib='colorSpace') @property def emissionRGB(self): """Diffuse color of the material.""" return self._emissionRGB[:3] @emissionRGB.setter def emissionRGB(self, value): # make sure the color we got is 32-bit float self._emissionRGB = np.zeros((4,), np.float32) self._emissionRGB[:3] = (value * self.contrast + 1) / 2.0 self._emissionRGB[3] = self.opacity @property def shininess(self): return self._shininess @shininess.setter def shininess(self, value): self._shininess = float(value)
[docs]def useMaterial(material, useTextures=True): """Use a material for proceeding vertex draws. Parameters ---------- material : :obj:`Material` or None Material descriptor to use. Default material properties are set if None is specified. This is equivalent to disabling materials. useTextures : :obj:`bool` Enable textures. Textures specified in a material descriptor's 'texture' attribute will be bound and their respective texture units will be enabled. Note, when disabling materials, the value of useTextures must match the previous call. If there are no textures attached to the material, useTexture will be silently ignored. Returns ------- None Notes ----- 1. If a material mode has a value of None, a color with all components 0.0 will be assigned. 2. Material colors and shininess values are accessible from shader programs after calling 'useMaterial'. Values can be accessed via built-in 'gl_FrontMaterial' and 'gl_BackMaterial' structures (e.g. gl_FrontMaterial.diffuse). Examples -------- Use a material when drawing:: useMaterial(metalMaterials.gold) drawVAO( ... ) # all meshes drawn will be gold useMaterial(None) # turn off material when done """ if material is not None: GL.glDisable(GL.GL_COLOR_MATERIAL) # disable color tracking face = material._face GL.glColorMaterial(face, GL.GL_AMBIENT_AND_DIFFUSE) # convert data in light class to ctypes diffuse = np.ctypeslib.as_ctypes(material._diffuseRGB) specular = np.ctypeslib.as_ctypes(material._specularRGB) ambient = np.ctypeslib.as_ctypes(material._ambientRGB) emission = np.ctypeslib.as_ctypes(material._emissionRGB) # pass values to OpenGL GL.glMaterialfv(face, GL.GL_DIFFUSE, diffuse) GL.glMaterialfv(face, GL.GL_SPECULAR, specular) GL.glMaterialfv(face, GL.GL_AMBIENT, ambient) GL.glMaterialfv(face, GL.GL_EMISSION, emission) GL.glMaterialf(face, GL.GL_SHININESS, material.shininess) # setup textures if useTextures and material.diffuseTexture is not None: material._useTextures = True GL.glEnable(GL.GL_TEXTURE_2D) if material.diffuseTexture is not None: bindTexture(material.diffuseTexture, 0) else: material._useTextures = False GL.glBindTexture(GL.GL_TEXTURE_2D, 0) GL.glDisable(GL.GL_TEXTURE_2D) else: for mode, param in defaultMaterial.params.items(): GL.glEnable(GL.GL_COLOR_MATERIAL) GL.glMaterialfv(GL.GL_FRONT_AND_BACK, mode, param)
def clearMaterial(material): """Stop using a material.""" for mode, param in defaultMaterial.params.items(): GL.glMaterialfv(GL.GL_FRONT_AND_BACK, mode, param) if material._useTextures: if material.diffuseTexture is not None: unbindTexture(material.diffuseTexture) GL.glDisable(GL.GL_TEXTURE_2D) GL.glDisable(GL.GL_COLOR_MATERIAL) # disable color tracking # ------------------------- # Lighting Helper Functions # ------------------------- Light = namedtuple('Light', ['params', 'userData'])
[docs]def createLight(params=()): """Create a point light source. """ # setup light mode/value slots lightDesc = Light({mode: None for mode in ( GL.GL_AMBIENT, GL.GL_DIFFUSE, GL.GL_SPECULAR, GL.GL_POSITION, GL.GL_SPOT_CUTOFF, GL.GL_SPOT_DIRECTION, GL.GL_SPOT_EXPONENT, GL.GL_CONSTANT_ATTENUATION, GL.GL_LINEAR_ATTENUATION, GL.GL_QUADRATIC_ATTENUATION)}, dict()) # configure lights if params: for mode, value in params: if value is not None: if mode in [GL.GL_AMBIENT, GL.GL_DIFFUSE, GL.GL_SPECULAR, GL.GL_POSITION]: lightDesc.params[mode] = (GL.GLfloat * 4)(*value) elif mode == GL.GL_SPOT_DIRECTION: lightDesc.params[mode] = (GL.GLfloat * 3)(*value) else: lightDesc.params[mode] = GL.GLfloat(value) return lightDesc
[docs]def useLights(lights, setupOnly=False): """Use specified lights in successive rendering operations. All lights will be transformed using the present modelview matrix. Parameters ---------- lights : :obj:`List` of :obj:`Light` or None Descriptor of a light source. If None, lighting is disabled. setupOnly : :obj:`bool`, optional Do not enable lighting or lights. Specify True if lighting is being computed via fragment shaders. """ if lights is not None: if len(lights) > getIntegerv(GL.GL_MAX_LIGHTS): raise IndexError("Number of lights specified > GL_MAX_LIGHTS.") GL.glEnable(GL.GL_NORMALIZE) for index, light in enumerate(lights): enumLight = GL.GL_LIGHT0 + index # light properties for mode, value in light.params.items(): if value is not None: GL.glLightfv(enumLight, mode, value) if not setupOnly: GL.glEnable(enumLight) if not setupOnly: GL.glEnable(GL.GL_LIGHTING) else: # disable lights if not setupOnly: for enumLight in range(getIntegerv(GL.GL_MAX_LIGHTS)): GL.glDisable(GL.GL_LIGHT0 + enumLight) GL.glDisable(GL.GL_NORMALIZE) GL.glDisable(GL.GL_LIGHTING)
[docs]def setAmbientLight(color): """Set the global ambient lighting for the scene when lighting is enabled. This is equivalent to GL.glLightModelfv(GL.GL_LIGHT_MODEL_AMBIENT, color) and does not contribute to the GL_MAX_LIGHTS limit. Parameters ---------- color : :obj:`tuple` Ambient lighting RGBA intensity for the whole scene. Notes ----- If unset, the default value is (0.2, 0.2, 0.2, 1.0) when GL_LIGHTING is enabled. """ GL.glLightModelfv(GL.GL_LIGHT_MODEL_AMBIENT, (GL.GLfloat * 4)(*color))
# ------------------------- # 3D Model Helper Functions # ------------------------- # # These functions are used in the creation, manipulation and rendering of 3D # model data. #
[docs]class ObjMeshInfo(object): """Descriptor for mesh data loaded from a Wavefront OBJ file. """ __slots__ = [ 'vertexPos', 'texCoords', 'normals', 'faces', 'extents', 'mtlFile']
[docs] def __init__(self, vertexPos=None, texCoords=None, normals=None, faces=None, extents=None, mtlFile=None): self.vertexPos = vertexPos self.texCoords = texCoords self.normals = normals self.faces = faces self.extents = extents self.mtlFile = mtlFile
[docs]def loadObjFile(objFile): """Load a Wavefront OBJ file (*.obj). Loads vertex, normals, and texture coordinates from the provided *.obj file into arrays. These arrays can be processed then loaded into vertex buffer objects (VBOs) for rendering. The *.obj file must at least specify vertex position data to be loaded successfully. Normals and texture coordinates are optional. Faces can be either triangles or quads, but not both. Faces are grouped by their materials. Index arrays are generated for each material present in the file. Data from the returned `ObjMeshInfo` object can be used to create vertex buffer objects and arrays for rendering. See `Examples` below for details on how to do this. Parameters ---------- objFile : :obj:`str` Path to the *.OBJ file to load. Returns ------- ObjMeshInfo Mesh data. See Also -------- loadMtlFile : Load a *.mtl file. Notes ----- 1. This importer should work fine for most sanely generated files. Export your model with Blender for best results, even if you used some other package to create it. 2. The mesh cannot contain both triangles and quads. Examples -------- Loading a *.OBJ mode from file:: objModel = loadObjFile('/path/to/file.obj') # load the material (*.mtl) file, textures are also loaded mtllib = loadMtl('/path/to/' + objModel.mtlFile) Creating separate vertex buffer objects (VBOs) for each vertex attribute:: vertexPosVBO = createVBO(objModel.vertexPos) texCoordVBO = createVBO(objModel.texCoords) normalsVBO = createVBO(objModel.normals) Create vertex array objects (VAOs) to draw the mesh. We create VAOs for each face material:: objVAOs = {} # dictionary for VAOs # for each material create a VAO # keys are material names, values are index buffers for material, faces in objModel.faces.items(): # convert index buffer to VAO indexBuffer = \ gltools.createVBO( faces.flatten(), # flatten face index for element array target=GL.GL_ELEMENT_ARRAY_BUFFER, dataType=GL.GL_UNSIGNED_INT) # see `setVertexAttribPointer` for more information about attribute # pointer indices objVAOs[material] = gltools.createVAO( {0: vertexPosVBO, # 0 = gl_Vertex 8: texCoordVBO, # 8 = gl_MultiTexCoord0 2: normalsVBO}, # 2 = gl_Normal indexBuffer=indexBuffer) # if using legacy attribute pointers, do this instead ... # objVAOs[key] = createVAO({GL_VERTEX_ARRAY: vertexPosVBO, # GL_TEXTURE_COORD_ARRAY: texCoordVBO, # GL_NORMAL_ARRAY: normalsVBO}, # indexBuffer=indexBuffer, # legacy=True) # this needs to be `True` To render the VAOs using `objVAOs` created above, do the following:: for material, vao in objVAOs.items(): useMaterial(mtllib[material]) drawVAO(vao) useMaterial(None) # disable materials when done Optionally, you can create a single-storage, interleaved VBO by using `numpy.hstack`. On some GL implementations, using single-storage buffers offers better performance:: interleavedData = numpy.hstack( (objModel.vertexPos, objModel.texCoords, objModel.normals)) vertexData = createVBO(interleavedData) Creating VAOs with interleaved, single-storage buffers require specifying additional information, such as `size` and `offset`:: objVAOs = {} for key, val in objModel.faces.items(): indexBuffer = \ gltools.createVBO( faces.flatten(), target=GL.GL_ELEMENT_ARRAY_BUFFER, dataType=GL.GL_UNSIGNED_INT) objVAOs[key] = createVAO({0: (vertexData, 3, 0), # size=3, offset=0 8: (vertexData, 2, 3), # size=2, offset=3 2: (vertexData, 3, 5), # size=3, offset=5 indexBuffer=val) Drawing VAOs with interleaved buffers is exactly the same as shown before with separate buffers. """ # open the file, read it into memory with open(objFile, 'r') as f: objBuffer = StringIO(f.read()) mtlFile = None # unsorted attribute data lists positionDefs = [] texCoordDefs = [] normalDefs = [] vertexAttrs = {} # material groups materialGroup = None materialGroups = {} nVertices = nTextureCoords = nNormals = nFaces = 0 vertexIdx = 0 # first pass, examine the file and load up vertex attributes for line in objBuffer.readlines(): line = line.strip() # clean up like if line.startswith('v '): positionDefs.append(tuple(map(float, line[2:].split(' ')))) nVertices += 1 elif line.startswith('vt '): texCoordDefs.append(tuple(map(float, line[3:].split(' ')))) nTextureCoords += 1 elif line.startswith('vn '): normalDefs.append(tuple(map(float, line[3:].split(' ')))) nNormals += 1 elif line.startswith('f '): faceAttrs = [] # attributes this face for attrs in line[2:].split(' '): # triangle vertex attrs if attrs not in vertexAttrs.keys(): vertexAttrs[attrs] = vertexIdx vertexIdx += 1 faceAttrs.append(vertexAttrs[attrs]) materialGroups[materialGroup].append(faceAttrs) nFaces += 1 elif line.startswith('o '): # ignored for now pass elif line.startswith('g '): # ignored for now pass elif line.startswith('usemtl '): foundMaterial = line[7:] if foundMaterial not in materialGroups.keys(): materialGroups[foundMaterial] = [] materialGroup = foundMaterial elif line.startswith('mtllib '): mtlFile = line.strip()[7:] # at the very least, we need vertices and facedefs if nVertices == 0 or nFaces == 0: raise RuntimeError( "Failed to load OBJ file, file contains no vertices or faces.") # convert indices for materials to numpy arrays for key, val in materialGroups.items(): materialGroups[key] = np.asarray(val, dtype=np.int) # indicate if file has any texture coordinates of normals hasTexCoords = nTextureCoords > 0 hasNormals = nNormals > 0 # lists for vertex attributes vertexPos = [] vertexTexCoord = [] vertexNormal = [] # populate vertex attribute arrays for attrs, idx in vertexAttrs.items(): attr = attrs.split('/') vertexPos.append(positionDefs[int(attr[0]) - 1]) if len(attr) > 1: # has texture coords if hasTexCoords: if attr[1] != '': # texcoord field not empty vertexTexCoord.append(texCoordDefs[int(attr[1]) - 1]) else: vertexTexCoord.append([0., 0.]) # fill with zeros if len(attr) > 2: # has normals too if hasNormals: vertexNormal.append(normalDefs[int(attr[2]) - 1]) else: vertexNormal.append([0., 0., 0.]) # fill with zeros # convert vertex attribute lists to numeric arrays vertexPos = np.asarray(vertexPos) vertexTexCoord = np.asarray(vertexTexCoord) vertexNormal = np.asarray(vertexNormal) # compute the extents of the model, needed for axis-aligned bounding boxes extents = (vertexPos.min(axis=0), vertexPos.max(axis=0)) # resolve the path to the material file associated with the mesh if mtlFile is not None: mtlFile = os.path.join(os.path.split(objFile)[0], mtlFile) return ObjMeshInfo(vertexPos, vertexTexCoord, vertexNormal, materialGroups, extents, mtlFile)
[docs]def loadMtlFile(mtllib, texParams=None): """Load a material library file (*.mtl). Parameters ---------- mtllib : str Path to the material library file. texParams : list or tuple Optional texture parameters for loaded textures. Texture parameters are specified as a list of tuples. Each item specifies the option and parameter. For instance, `[(GL.GL_TEXTURE_MAG_FILTER, GL.GL_LINEAR), ...]`. By default, linear filtering is used for both the minifying and magnification filter functions. This is adequate for most uses. Returns ------- dict Dictionary of materials. Where each key is the material name found in the file, and values are `Material` namedtuple objects. See Also -------- loadObjFile : Load an *.OBJ file. Examples -------- Load material associated with an *.OBJ file:: objModel = loadObjFile('/path/to/file.obj') # load the material (*.mtl) file, textures are also loaded mtllib = loadMtl('/path/to/' + objModel.mtlFile) Use a material when rendering vertex arrays:: useMaterial(mtllib[material]) drawVAO(vao) useMaterial(None) # disable materials when done """ # open the file, read it into memory with open(mtllib, 'r') as mtlFile: mtlBuffer = StringIO(mtlFile.read()) # default texture parameters if texParams is None: texParams = {GL.GL_TEXTURE_MAG_FILTER: GL.GL_LINEAR, GL.GL_TEXTURE_MIN_FILTER: GL.GL_LINEAR} foundMaterials = {} foundTextures = {} thisMaterial = 0 for line in mtlBuffer.readlines(): line = line.strip() if line.startswith('newmtl '): # new material thisMaterial = line[7:] foundMaterials[thisMaterial] = SimpleMaterial() elif line.startswith('Ns '): # specular exponent foundMaterials[thisMaterial].shininess = line[3:] elif line.startswith('Ks '): # specular color specularColor = np.asarray(list(map(float, line[3:].split(' ')))) specularColor = 2.0 * specularColor - 1 foundMaterials[thisMaterial].specularColor = specularColor elif line.startswith('Kd '): # diffuse color diffuseColor = np.asarray(list(map(float, line[3:].split(' ')))) diffuseColor = 2.0 * diffuseColor - 1 foundMaterials[thisMaterial].diffuseColor = diffuseColor elif line.startswith('Ka '): # ambient color ambientColor = np.asarray(list(map(float, line[3:].split(' ')))) ambientColor = 2.0 * ambientColor - 1 foundMaterials[thisMaterial].ambientColor = ambientColor elif line.startswith('map_Kd '): # diffuse color map # load a diffuse texture from file textureName = line[7:] if textureName not in foundTextures.keys(): im = Image.open( os.path.join(os.path.split(mtllib)[0], textureName)) im = im.transpose(Image.FLIP_TOP_BOTTOM) im = im.convert("RGBA") pixelData = np.array(im).ctypes width = pixelData.shape[1] height = pixelData.shape[0] foundTextures[textureName] = createTexImage2D( width, height, internalFormat=GL.GL_RGBA, pixelFormat=GL.GL_RGBA, dataType=GL.GL_UNSIGNED_BYTE, data=pixelData, unpackAlignment=1, texParams=texParams) foundMaterials[thisMaterial].diffuseTexture = \ foundTextures[textureName] return foundMaterials
[docs]def createUVSphere(radius=0.5, sectors=16, stacks=16, flipFaces=False): """Create a UV sphere. Procedurally generate a UV sphere by specifying its radius, and number of stacks and sectors. The poles of the resulting sphere will be aligned with the Z-axis. Surface normals and texture coordinates are automatically generated. The returned normals are computed to produce smooth shading. Parameters ---------- radius : float, optional Radius of the sphere in scene units (usually meters). Default is 0.5. sectors, stacks : int, optional Number of longitudinal and latitudinal sub-divisions. Default is 16 for both. flipFaces : bool, optional If `True`, normals and face windings will be set to point inward towards the center of the sphere. Texture coordinates will remain the same. Default is `False`. Returns ------- tuple Vertex attribute arrays (position, texture coordinates, and normals) and triangle indices. Examples -------- Create a UV sphere and VAO to render it:: vertices, textureCoords, normals, faces = \ gltools.createUVSphere(sectors=32, stacks=32) vertexVBO = gltools.createVBO(vertices) texCoordVBO = gltools.createVBO(textureCoords) normalsVBO = gltools.createVBO(normals) indexBuffer = gltools.createVBO( faces.flatten(), target=GL.GL_ELEMENT_ARRAY_BUFFER, dataType=GL.GL_UNSIGNED_INT) vao = gltools.createVAO({0: vertexVBO, 8: texCoordVBO, 2: normalsVBO}, indexBuffer=indexBuffer) # in the rendering loop gltools.drawVAO(vao, GL.GL_TRIANGLES) The color of the sphere can be changed by calling `glColor*`:: glColor4f(1.0, 0.0, 0.0, 1.0) # red gltools.drawVAO(vao, GL.GL_TRIANGLES) Raw coordinates can be transformed prior to uploading to VBOs. Here we can rotate vertex positions and normals so the equator rests on Z-axis:: r = mt.rotationMatrix(90.0, (1.0, 0, 0.0)) # 90 degrees about +X axis vertices = mt.applyMatrix(r, vertices) normals = mt.applyMatrix(r, normals) """ # based of the code found here http://www.songho.ca/opengl/gl_sphere.html sectorStep = 2.0 * np.pi / sectors stackStep = np.pi / stacks lengthInv = 1.0 / radius vertices = [] normals = [] texCoords = [] for i in range(stacks + 1): stackAngle = np.pi / 2.0 - i * stackStep xy = radius * np.cos(stackAngle) z = radius * np.sin(stackAngle) for j in range(sectors + 1): sectorAngle = j * sectorStep x = xy * np.cos(sectorAngle) y = xy * np.sin(sectorAngle) vertices.append((x, y, z)) nx = x * lengthInv ny = y * lengthInv nz = z * lengthInv normals.append((nx, ny, nz)) s = 1.0 - j / float(sectors) t = i / float(stacks) texCoords.append((s, t)) # generate index indices = [] for i in range(stacks): k1 = i * (sectors + 1) k2 = k1 + sectors + 1 for j in range(sectors): # case for caps if not flipFaces: if i != 0: indices.append((k1, k2, k1 + 1)) if i != stacks - 1: indices.append((k1 + 1, k2, k2 + 1)) else: if i != 0: indices.append((k1, k1 + 1, k2)) if i != stacks - 1: indices.append((k1 + 1, k2 + 1, k2)) k1 += 1 k2 += 1 # convert to numpy arrays vertices = np.ascontiguousarray(vertices, dtype=np.float32) normals = np.ascontiguousarray(normals, dtype=np.float32) texCoords = np.ascontiguousarray(texCoords, dtype=np.float32) faces = np.ascontiguousarray(indices, dtype=np.uint32) if flipFaces: # flip normals so they point inwards normals *= -1.0 return vertices, texCoords, normals, faces
[docs]def createPlane(size=(1., 1.)): """Create a plane. Procedurally generate a plane (or quad) mesh by specifying its size. Texture coordinates are computed automatically, with origin at the bottom left of the plane. The generated plane is perpendicular to the +Z axis, origin of the plane is at its center. Parameters ---------- size : tuple or float Dimensions of the plane. If a single value is specified, the plane will be square. Provide a tuple of floats to specify the width and length of the plane (eg. `size=(0.2, 1.3)`). Returns ------- tuple Vertex attribute arrays (position, texture coordinates, and normals) and triangle indices. Examples -------- Create a plane mesh and draw it:: vertices, textureCoords, normals, faces = gltools.createPlane() vertexVBO = gltools.createVBO(vertices) texCoordVBO = gltools.createVBO(textureCoords) normalsVBO = gltools.createVBO(normals) indexBuffer = gltools.createVBO( faces.flatten(), target=GL.GL_ELEMENT_ARRAY_BUFFER, dataType=GL.GL_UNSIGNED_INT) vao = gltools.createVAO({0: vertexVBO, 8: texCoordVBO, 2: normalsVBO}, indexBuffer=indexBuffer) # in the rendering loop gltools.drawVAO(vao, GL.GL_TRIANGLES) """ if isinstance(size, (int, float,)): sx = sy = float(size) / 2. else: sx = size[0] / 2. sy = size[1] / 2. vertices = np.ascontiguousarray( [[-1., 1., 0.], [ 1., 1., 0.], [-1., -1., 0.], [ 1., -1., 0.]]) if sx != 1.: vertices[:, 0] *= sx if sy != 1.: vertices[:, 1] *= sy # texture coordinates texCoords = np.ascontiguousarray([[0., 1.], [1., 1.], [0., 0.], [1., 0.]]) # normals, facing +Z normals = np.zeros_like(vertices) normals[:, 0] = 0. normals[:, 1] = 0. normals[:, 2] = 1. # generate face index faces = np.ascontiguousarray([[0, 2, 1], [1, 2, 3]], dtype=np.uint32) return vertices, texCoords, normals, faces
[docs]def createMeshGridFromArrays(xvals, yvals, zvals=None, tessMode='diag', computeNormals=True): """Create a mesh grid using coordinates from arrays. Generates a mesh using data in provided in 2D arrays of vertex coordinates. Triangle faces are automatically computed by this function by joining adjacent vertices at neighbouring indices in the array. Texture coordinates are generated covering the whole mesh, with origin at the bottom left. Parameters ---------- xvals, yvals : array_like NxM arrays of X and Y coordinates. Both arrays must have the same shape. the resulting mesh will have a single vertex for each X and Y pair. Faces will be generated to connect adjacent coordinates in the array. zvals : array_like, optional NxM array of Z coordinates for each X and Y. Must have the same shape as X and Y. If not specified, the Z coordinates will be filled with zeros. tessMode : str, optional Tessellation mode. Specifies how faces are generated. Options are 'center', 'radial', and 'diag'. Default is 'diag'. Modes 'radial' and 'center' work best with odd numbered array dimensions. computeNormals : bool, optional Compute normals for the generated mesh. If `False`, all normals are set to face in the +Z direction. Presently, computing normals is a slow operation and may not be needed for some meshes. Returns ------- tuple Vertex attribute arrays (position, texture coordinates, and normals) and triangle indices. Examples -------- Create a 3D sine grating mesh using 2D arrays:: x = np.linspace(0, 1.0, 32) y = np.linspace(1.0, 0.0, 32) xx, yy = np.meshgrid(x, y) zz = np.tile(np.sin(np.linspace(0.0, 32., 32)) * 0.02, (32, 1)) vertices, textureCoords, normals, faces = \ gltools.createMeshGridFromArrays(xx, yy, zz) """ vertices = np.vstack([xvals.ravel(), yvals.ravel()]).T if zvals is not None: assert xvals.shape == yvals.shape == zvals.shape else: assert xvals.shape == yvals.shape if zvals is None: # fill z with zeros if not provided vertices = np.hstack([vertices, np.zeros((vertices.shape[0], 1))]) else: vertices = np.hstack([vertices, np.atleast_2d(zvals.ravel()).T]) ny, nx = xvals.shape # texture coordinates u = np.linspace(0.0, 1.0, nx) v = np.linspace(1.0, 0.0, ny) uu, vv = np.meshgrid(u, v) texCoords = np.vstack([uu.ravel(), vv.ravel()]).T # generate face index faces = [] if tessMode == 'diag': for i in range(ny - 1): k1 = i * nx k2 = k1 + nx for j in range(nx - 1): faces.append([k1, k2, k1 + 1]) faces.append([k1 + 1, k2, k2 + 1]) k1 += 1 k2 += 1 else: raise ValueError('Invalid value for `tessMode`.') # convert to numpy arrays vertices = np.ascontiguousarray(vertices, dtype=np.float32) texCoords = np.ascontiguousarray(texCoords, dtype=np.float32) faces = np.ascontiguousarray(faces, dtype=np.uint32) # calculate surface normals for the mesh if computeNormals: normals = calculateVertexNormals(vertices, faces, shading='smooth') else: normals = np.zeros_like(vertices, dtype=np.float32) normals[:, 2] = 1. return vertices, texCoords, normals, faces
[docs]def createMeshGrid(size=(1., 1.), subdiv=0, tessMode='diag'): """Create a grid mesh. Procedurally generate a grid mesh by specifying its size and number of sub-divisions. Texture coordinates are computed automatically. The origin is at the center of the mesh. The generated grid is perpendicular to the +Z axis, origin of the grid is at its center. Parameters ---------- size : tuple or float Dimensions of the mesh. If a single value is specified, the plane will be square. Provide a tuple of floats to specify the width and length of the plane (eg. `size=(0.2, 1.3)`). subdiv : int, optional Number of subdivisions. Zero subdivisions are applied by default, and the resulting mesh will only have vertices at the corners. tessMode : str, optional Tessellation mode. Specifies how faces are subdivided. Options are 'center', 'radial', and 'diag'. Default is 'diag'. Modes 'radial' and 'center' work best with an odd number of subdivisions. Returns ------- tuple Vertex attribute arrays (position, texture coordinates, and normals) and triangle indices. Examples -------- Create a grid mesh and draw it:: vertices, textureCoords, normals, faces = gltools.createPlane() vertexVBO = gltools.createVBO(vertices) texCoordVBO = gltools.createVBO(textureCoords) normalsVBO = gltools.createVBO(normals) indexBuffer = gltools.createVBO( faces.flatten(), target=GL.GL_ELEMENT_ARRAY_BUFFER, dataType=GL.GL_UNSIGNED_INT) vao = gltools.createVAO({0: vertexVBO, 8: texCoordVBO, 2: normalsVBO}, indexBuffer=indexBuffer) # in the rendering loop gltools.drawVAO(vao, GL.GL_TRIANGLES) Randomly displace vertices off the plane of the grid by setting the `Z` value per vertex:: vertices, textureCoords, normals, faces = \ gltools.createMeshGrid(subdiv=11) numVerts = vertices.shape[0] vertices[:, 2] = np.random.uniform(-0.02, 0.02, (numVerts,))) # Z # you must recompute surface normals to get correct shading! normals = gltools.calculateVertexNormals(vertices, faces) # create a VAO as shown in the previous example here to draw it ... """ if isinstance(size, (int, float,)): divx = divy = float(size) / 2. else: divx = size[0] / 2. divy = size[1] / 2. # generate plane vertices x = np.linspace(-divx, divx, subdiv + 2) y = np.linspace(divy, -divy, subdiv + 2) xx, yy = np.meshgrid(x, y) vertices = np.vstack([xx.ravel(), yy.ravel()]).T vertices = np.hstack([vertices, np.zeros((vertices.shape[0], 1))]) # add z # texture coordinates u = np.linspace(0.0, 1.0, subdiv + 2) v = np.linspace(1.0, 0.0, subdiv + 2) uu, vv = np.meshgrid(u, v) texCoords = np.vstack([uu.ravel(), vv.ravel()]).T # normals, facing +Z normals = np.zeros_like(vertices) normals[:, 0] = 0. normals[:, 1] = 0. normals[:, 2] = 1. # generate face index faces = [] if tessMode == 'diag': for i in range(subdiv + 1): k1 = i * (subdiv + 2) k2 = k1 + subdiv + 2 for j in range(subdiv + 1): faces.append([k1, k2, k1 + 1]) faces.append([k1 + 1, k2, k2 + 1]) k1 += 1 k2 += 1 elif tessMode == 'center': lx = len(x) ly = len(y) for i in range(subdiv + 1): k1 = i * (subdiv + 2) k2 = k1 + subdiv + 2 for j in range(subdiv + 1): if k1 + j < k1 + int((lx / 2)): if int(k1 / ly) + 1 > int(ly / 2): faces.append([k1, k2, k1 + 1]) faces.append([k1 + 1, k2, k2 + 1]) else: faces.append([k1, k2, k2 + 1]) faces.append([k1 + 1, k1, k2 + 1]) else: if int(k1 / ly) + 1 > int(ly / 2): faces.append([k1, k2, k2 + 1]) faces.append([k1 + 1, k1, k2 + 1]) else: faces.append([k1, k2, k1 + 1]) faces.append([k1 + 1, k2, k2 + 1]) k1 += 1 k2 += 1 elif tessMode == 'radial': lx = len(x) ly = len(y) for i in range(subdiv + 1): k1 = i * (subdiv + 2) k2 = k1 + subdiv + 2 for j in range(subdiv + 1): if k1 + j < k1 + int((lx / 2)): if int(k1 / ly) + 1 > int(ly / 2): faces.append([k1, k2, k2 + 1]) faces.append([k1 + 1, k1, k2 + 1]) else: faces.append([k1, k2, k1 + 1]) faces.append([k1 + 1, k2, k2 + 1]) else: if int(k1 / ly) + 1 > int(ly / 2): faces.append([k1, k2, k1 + 1]) faces.append([k1 + 1, k2, k2 + 1]) else: faces.append([k1, k2, k2 + 1]) faces.append([k1 + 1, k1, k2 + 1]) k1 += 1 k2 += 1 else: raise ValueError('Invalid value for `tessMode`.') # convert to numpy arrays vertices = np.ascontiguousarray(vertices, dtype=np.float32) texCoords = np.ascontiguousarray(texCoords, dtype=np.float32) normals = np.ascontiguousarray(normals, dtype=np.float32) faces = np.ascontiguousarray(faces, dtype=np.uint32) return vertices, texCoords, normals, faces
[docs]def createBox(size=(1., 1., 1.), flipFaces=False): """Create a box mesh. Create a box mesh by specifying its `size` in three dimensions (x, y, z), or a single value (`float`) to create a cube. The resulting box will be centered about the origin. Texture coordinates and normals are automatically generated for each face. Setting `flipFaces=True` will make faces and normals point inwards, this allows boxes to be viewed and lit correctly from the inside. Parameters ---------- size : tuple or float Dimensions of the mesh. If a single value is specified, the box will be a cube. Provide a tuple of floats to specify the width, length, and height of the box (eg. `size=(0.2, 1.3, 2.1)`). flipFaces : bool, optional If `True`, normals and face windings will be set to point inward towards the center of the box. Texture coordinates will remain the same. Default is `False`. Returns ------- tuple Vertex attribute arrays (position, texture coordinates, and normals) and triangle indices. Examples -------- Create a box mesh and draw it:: vertices, textureCoords, normals, faces = gltools.createBox() vertexVBO = gltools.createVBO(vertices) texCoordVBO = gltools.createVBO(textureCoords) normalsVBO = gltools.createVBO(normals) indexBuffer = gltools.createVBO( faces.flatten(), target=GL.GL_ELEMENT_ARRAY_BUFFER, dataType=GL.GL_UNSIGNED_INT) vao = gltools.createVAO({0: vertexVBO, 8: texCoordVBO, 2: normalsVBO}, indexBuffer=indexBuffer) # in the rendering loop gltools.drawVAO(vao, GL.GL_TRIANGLES) """ if isinstance(size, (int, float,)): sx = sy = sz = float(size) / 2. else: sx, sy, sz = size sx /= 2. sy /= 2. sz /= 2. # vertices vertices = np.ascontiguousarray([ [ 1., 1., 1.], [ 1., 1., -1.], [ 1., -1., 1.], [ 1., -1., -1.], [-1., 1., -1.], [-1., 1., 1.], [-1., -1., -1.], [-1., -1., 1.], [-1., 1., -1.], [ 1., 1., -1.], [-1., 1., 1.], [ 1., 1., 1.], [ 1., -1., -1.], [-1., -1., -1.], [ 1., -1., 1.], [-1., -1., 1.], [-1., 1., 1.], [ 1., 1., 1.], [-1., -1., 1.], [ 1., -1., 1.], [ 1., 1., -1.], [-1., 1., -1.], [ 1., -1., -1.], [-1., -1., -1.] ], dtype=np.float32) # multiply vertex coordinates by box dimensions if sx != 1.: vertices[:, 0] *= sx if sy != 1.: vertices[:, 1] *= sy if sz != 1.: vertices[:, 2] *= sz # normals for each side normals = np.repeat( [[ 1., 0., 0.], # +X [-1., 0., 0.], # -X [ 0., 1., 0.], # +Y [ 0., -1., 0.], # -Y [ 0., 0., 1.], # +Z [ 0., 0., -1.]], # -Z 4, axis=0) normals = np.ascontiguousarray(normals, dtype=np.float32) # texture coordinates for each side texCoords = np.tile([[0., 1.], [1., 1.], [0., 0.], [1., 0.]], (6, 1)) texCoords = np.ascontiguousarray(texCoords, dtype=np.float32) # vertex indices for faces faces = np.ascontiguousarray([ [ 0, 2, 1], [ 1, 2, 3], # +X [ 4, 6, 5], [ 5, 6, 7], # -X [ 8, 10, 9], [ 9, 10, 11], # +Y [12, 14, 13], [13, 14, 15], # -Y [16, 18, 17], [17, 18, 19], # +Z [20, 22, 21], [21, 22, 23] # -Z ], dtype=np.uint32) if flipFaces: faces = np.fliplr(faces) normals *= -1.0 return vertices, texCoords, normals, faces
[docs]def transformMeshPosOri(vertices, normals, pos=(0., 0., 0.), ori=(0., 0., 0., 1.)): """Transform a mesh. Transform mesh vertices and normals to a new position and orientation using a position coordinate and rotation quaternion. Values `vertices` and `normals` must be the same shape. This is intended to be used when editing raw vertex data prior to rendering. Do not use this to change the configuration of an object while rendering. Parameters ---------- vertices : array_like Nx3 array of vertices. normals : array_like Nx3 array of normals. pos : array_like, optional Position vector to transform mesh vertices. If Nx3, `vertices` will be transformed by corresponding rows of `pos`. ori : array_like, optional Orientation quaternion in form [x, y, z, w]. If Nx4, `vertices` and `normals` will be transformed by corresponding rows of `ori`. Returns ------- tuple Transformed vertices and normals. Examples -------- Create and re-orient a plane to face upwards:: vertices, textureCoords, normals, faces = createPlane() # rotation quaternion qr = quatFromAxisAngle((1., 0., 0.), -90.0) # -90 degrees about +X axis # transform the normals and points vertices, normals = transformMeshPosOri(vertices, normals, ori=qr) Any `create*` primitive generating function can be used inplace of `createPlane`. """ # ensure these are contiguous vertices = np.ascontiguousarray(vertices) normals = np.ascontiguousarray(normals) if not np.allclose(pos, [0., 0., 0.]): vertices = mt.transform(pos, ori, vertices) if not np.allclose(ori, [0., 0., 0., 1.]): normals = mt.applyQuat(ori, normals) return vertices, normals
[docs]def calculateVertexNormals(vertices, faces, shading='smooth'): """Calculate vertex normals given vertices and triangle faces. Finds all faces sharing a vertex index and sets its normal to either the face normal if `shading='flat'` or the average normals of adjacent faces if `shading='smooth'`. Flat shading only works correctly if each vertex belongs to exactly one face. The direction of the normals are determined by the winding order of triangles, assumed counter clock-wise (OpenGL default). Most model editing software exports using this convention. If not, winding orders can be reversed by calling:: faces = np.fliplr(faces) In some case, creases may appear if vertices are at the same location, but do not share the same index. Parameters ---------- vertices : array_like Nx3 vertex positions. faces : array_like Nx3 vertex indices. shading : str, optional Shading mode. Options are 'smooth' and 'flat'. Flat only works with meshes where no vertex index is shared across faces. Returns ------- ndarray Vertex normals array with the shame shape as `vertices`. Computed normals are normalized. Examples -------- Recomputing vertex normals for a UV sphere:: # create a sphere and discard normals vertices, textureCoords, _, faces = gltools.createUVSphere() normals = gltools.calculateVertexNormals(vertices, faces) """ # compute surface normals for all faces faceNormals = mt.surfaceNormal(vertices[faces]) normals = [] if shading == 'flat': for vertexIdx in np.unique(faces): match, _ = np.where(faces == vertexIdx) normals.append(faceNormals[match, :]) elif shading == 'smooth': # get all faces the vertex belongs to for vertexIdx in np.unique(faces): match, _ = np.where(faces == vertexIdx) normals.append(mt.vertexNormal(faceNormals[match, :])) return np.ascontiguousarray(normals) + 0.0
# ----------------------------- # Misc. OpenGL Helper Functions # -----------------------------
[docs]def getIntegerv(parName): """Get a single integer parameter value, return it as a Python integer. Parameters ---------- pName : int OpenGL property enum to query (e.g. GL_MAJOR_VERSION). Returns ------- int """ val = GL.GLint() GL.glGetIntegerv(parName, val) return int(val.value)
[docs]def getFloatv(parName): """Get a single float parameter value, return it as a Python float. Parameters ---------- pName : float OpenGL property enum to query. Returns ------- float """ val = GL.GLfloat() GL.glGetFloatv(parName, val) return float(val.value)
[docs]def getString(parName): """Get a single string parameter value, return it as a Python UTF-8 string. Parameters ---------- pName : int OpenGL property enum to query (e.g. GL_VENDOR). Returns ------- str """ val = ctypes.cast(GL.glGetString(parName), ctypes.c_char_p).value return val.decode('UTF-8')
[docs]def getModelViewMatrix(): """Get the present model matrix from the OpenGL matrix stack. Returns ------- ndarray 4x4 model/view matrix. """ modelview = np.zeros((4, 4), dtype=np.float32) GL.glGetFloatv(GL.GL_MODELVIEW_MATRIX, modelview.ctypes.data_as( ctypes.POINTER(ctypes.c_float))) modelview[:, :] = np.transpose(modelview) return modelview
[docs]def getProjectionMatrix(): """Get the present projection matrix from the OpenGL matrix stack. Returns ------- ndarray 4x4 projection matrix. """ proj = np.zeros((4, 4), dtype=np.float32, order='C') GL.glGetFloatv(GL.GL_PROJECTION_MATRIX, proj.ctypes.data_as( ctypes.POINTER(ctypes.c_float))) proj[:, :] = np.transpose(proj) return proj
# OpenGL information type OpenGLInfo = namedtuple( 'OpenGLInfo', ['vendor', 'renderer', 'version', 'majorVersion', 'minorVersion', 'doubleBuffer', 'maxTextureSize', 'stereo', 'maxSamples', 'extensions', 'userData'])
[docs]def getOpenGLInfo(): """Get general information about the OpenGL implementation on this machine. This should provide a consistent means of doing so regardless of the OpenGL interface we are using. Returns are dictionary with the following fields:: vendor, renderer, version, majorVersion, minorVersion, doubleBuffer, maxTextureSize, stereo, maxSamples, extensions Supported extensions are returned as a list in the 'extensions' field. You can check if a platform supports an extension by checking the membership of the extension name in that list. Returns ------- OpenGLInfo """ return OpenGLInfo(getString(GL.GL_VENDOR), getString(GL.GL_RENDERER), getString(GL.GL_VERSION), getIntegerv(GL.GL_MAJOR_VERSION), getIntegerv(GL.GL_MINOR_VERSION), getIntegerv(GL.GL_DOUBLEBUFFER), getIntegerv(GL.GL_MAX_TEXTURE_SIZE), getIntegerv(GL.GL_STEREO), getIntegerv(GL.GL_MAX_SAMPLES), [i for i in getString(GL.GL_EXTENSIONS).split(' ')], dict())
# --------------------- # OpenGL/VRML Materials # --------------------- # # A collection of pre-defined materials for stimuli. Keep in mind that these # materials only approximate real-world equivalents. Values were obtained from # http://devernay.free.fr/cours/opengl/materials.html (08/24/18). There are four # material libraries to use, where individual material descriptors are accessed # via property names. # # Usage: # # useMaterial(metalMaterials.gold) # drawVAO(myObject) # ... # mineralMaterials = namedtuple( 'mineralMaterials', ['emerald', 'jade', 'obsidian', 'pearl', 'ruby', 'turquoise'])( createMaterial( [(GL.GL_AMBIENT, (0.0215, 0.1745, 0.0215, 1.0)), (GL.GL_DIFFUSE, (0.07568, 0.61424, 0.07568, 1.0)), (GL.GL_SPECULAR, (0.633, 0.727811, 0.633, 1.0)), (GL.GL_SHININESS, 0.6 * 128.0)]), createMaterial( [(GL.GL_AMBIENT, (0.135, 0.2225, 0.1575, 1.0)), (GL.GL_DIFFUSE, (0.54, 0.89, 0.63, 1.0)), (GL.GL_SPECULAR, (0.316228, 0.316228, 0.316228, 1.0)), (GL.GL_SHININESS, 0.1 * 128.0)]), createMaterial( [(GL.GL_AMBIENT, (0.05375, 0.05, 0.06625, 1.0)), (GL.GL_DIFFUSE, (0.18275, 0.17, 0.22525, 1.0)), (GL.GL_SPECULAR, (0.332741, 0.328634, 0.346435, 1.0)), (GL.GL_SHININESS, 0.3 * 128.0)]), createMaterial( [(GL.GL_AMBIENT, (0.25, 0.20725, 0.20725, 1.0)), (GL.GL_DIFFUSE, (1, 0.829, 0.829, 1.0)), (GL.GL_SPECULAR, (0.296648, 0.296648, 0.296648, 1.0)), (GL.GL_SHININESS, 0.088 * 128.0)]), createMaterial( [(GL.GL_AMBIENT, (0.1745, 0.01175, 0.01175, 1.0)), (GL.GL_DIFFUSE, (0.61424, 0.04136, 0.04136, 1.0)), (GL.GL_SPECULAR, (0.727811, 0.626959, 0.626959, 1.0)), (GL.GL_SHININESS, 0.6 * 128.0)]), createMaterial( [(GL.GL_AMBIENT, (0.1, 0.18725, 0.1745, 1.0)), (GL.GL_DIFFUSE, (0.396, 0.74151, 0.69102, 1.0)), (GL.GL_SPECULAR, (0.297254, 0.30829, 0.306678, 1.0)), (GL.GL_SHININESS, 0.1 * 128.0)]) ) metalMaterials = namedtuple( 'metalMaterials', ['brass', 'bronze', 'chrome', 'copper', 'gold', 'silver'])( createMaterial( [(GL.GL_AMBIENT, (0.329412, 0.223529, 0.027451, 1.0)), (GL.GL_DIFFUSE, (0.780392, 0.568627, 0.113725, 1.0)), (GL.GL_SPECULAR, (0.992157, 0.941176, 0.807843, 1.0)), (GL.GL_SHININESS, 0.21794872 * 128.0)]), createMaterial( [(GL.GL_AMBIENT, (0.2125, 0.1275, 0.054, 1.0)), (GL.GL_DIFFUSE, (0.714, 0.4284, 0.18144, 1.0)), (GL.GL_SPECULAR, (0.393548, 0.271906, 0.166721, 1.0)), (GL.GL_SHININESS, 0.2 * 128.0)]), createMaterial( [(GL.GL_AMBIENT, (0.25, 0.25, 0.25, 1.0)), (GL.GL_DIFFUSE, (0.4, 0.4, 0.4, 1.0)), (GL.GL_SPECULAR, (0.774597, 0.774597, 0.774597, 1.0)), (GL.GL_SHININESS, 0.6 * 128.0)]), createMaterial( [(GL.GL_AMBIENT, (0.19125, 0.0735, 0.0225, 1.0)), (GL.GL_DIFFUSE, (0.7038, 0.27048, 0.0828, 1.0)), (GL.GL_SPECULAR, (0.256777, 0.137622, 0.086014, 1.0)), (GL.GL_SHININESS, 0.1 * 128.0)]), createMaterial( [(GL.GL_AMBIENT, (0.24725, 0.1995, 0.0745, 1.0)), (GL.GL_DIFFUSE, (0.75164, 0.60648, 0.22648, 1.0)), (GL.GL_SPECULAR, (0.628281, 0.555802, 0.366065, 1.0)), (GL.GL_SHININESS, 0.4 * 128.0)]), createMaterial( [(GL.GL_AMBIENT, (0.19225, 0.19225, 0.19225, 1.0)), (GL.GL_DIFFUSE, (0.50754, 0.50754, 0.50754, 1.0)), (GL.GL_SPECULAR, (0.508273, 0.508273, 0.508273, 1.0)), (GL.GL_SHININESS, 0.4 * 128.0)]) ) plasticMaterials = namedtuple( 'plasticMaterials', ['black', 'cyan', 'green', 'red', 'white', 'yellow'])( createMaterial( [(GL.GL_AMBIENT, (0, 0, 0, 1.0)), (GL.GL_DIFFUSE, (0.01, 0.01, 0.01, 1.0)), (GL.GL_SPECULAR, (0.5, 0.5, 0.5, 1.0)), (GL.GL_SHININESS, 0.25 * 128.0)]), createMaterial( [(GL.GL_AMBIENT, (0, 0.1, 0.06, 1.0)), (GL.GL_DIFFUSE, (0.06, 0, 0.50980392, 1.0)), (GL.GL_SPECULAR, (0.50196078, 0.50196078, 0.50196078, 1.0)), (GL.GL_SHININESS, 0.25 * 128.0)]), createMaterial( [(GL.GL_AMBIENT, (0, 0, 0, 1.0)), (GL.GL_DIFFUSE, (0.1, 0.35, 0.1, 1.0)), (GL.GL_SPECULAR, (0.45, 0.55, 0.45, 1.0)), (GL.GL_SHININESS, 0.25 * 128.0)]), createMaterial( [(GL.GL_AMBIENT, (0, 0, 0, 1.0)), (GL.GL_DIFFUSE, (0.5, 0, 0, 1.0)), (GL.GL_SPECULAR, (0.7, 0.6, 0.6, 1.0)), (GL.GL_SHININESS, 0.25 * 128.0)]), createMaterial( [(GL.GL_AMBIENT, (0, 0, 0, 1.0)), (GL.GL_DIFFUSE, (0.55, 0.55, 0.55, 1.0)), (GL.GL_SPECULAR, (0.7, 0.7, 0.7, 1.0)), (GL.GL_SHININESS, 0.25 * 128.0)]), createMaterial( [(GL.GL_AMBIENT, (0, 0, 0, 1.0)), (GL.GL_DIFFUSE, (0.5, 0.5, 0, 1.0)), (GL.GL_SPECULAR, (0.6, 0.6, 0.5, 1.0)), (GL.GL_SHININESS, 0.25 * 128.0)]) ) rubberMaterials = namedtuple( 'rubberMaterials', ['black', 'cyan', 'green', 'red', 'white', 'yellow'])( createMaterial( [(GL.GL_AMBIENT, (0.02, 0.02, 0.02, 1.0)), (GL.GL_DIFFUSE, (0.01, 0.01, 0.01, 1.0)), (GL.GL_SPECULAR, (0.4, 0.4, 0.4, 1.0)), (GL.GL_SHININESS, 0.078125 * 128.0)]), createMaterial( [(GL.GL_AMBIENT, (0, 0.05, 0.05, 1.0)), (GL.GL_DIFFUSE, (0.4, 0.5, 0.5, 1.0)), (GL.GL_SPECULAR, (0.04, 0.7, 0.7, 1.0)), (GL.GL_SHININESS, 0.078125 * 128.0)]), createMaterial( [(GL.GL_AMBIENT, (0, 0.05, 0, 1.0)), (GL.GL_DIFFUSE, (0.4, 0.5, 0.4, 1.0)), (GL.GL_SPECULAR, (0.04, 0.7, 0.04, 1.0)), (GL.GL_SHININESS, 0.078125 * 128.0)]), createMaterial( [(GL.GL_AMBIENT, (0.05, 0, 0, 1.0)), (GL.GL_DIFFUSE, (0.5, 0.4, 0.4, 1.0)), (GL.GL_SPECULAR, (0.7, 0.04, 0.04, 1.0)), (GL.GL_SHININESS, 0.078125 * 128.0)]), createMaterial( [(GL.GL_AMBIENT, (0.05, 0.05, 0.05, 1.0)), (GL.GL_DIFFUSE, (0.5, 0.5, 0.5, 1.0)), (GL.GL_SPECULAR, (0.7, 0.7, 0.7, 1.0)), (GL.GL_SHININESS, 0.078125 * 128.0)]), createMaterial( [(GL.GL_AMBIENT, (0.05, 0.05, 0, 1.0)), (GL.GL_DIFFUSE, (0.5, 0.5, 0.4, 1.0)), (GL.GL_SPECULAR, (0.7, 0.7, 0.04, 1.0)), (GL.GL_SHININESS, 0.078125 * 128.0)]) ) # default material according to the OpenGL spec. defaultMaterial = createMaterial( [(GL.GL_AMBIENT, (0.2, 0.2, 0.2, 1.0)), (GL.GL_DIFFUSE, (0.8, 0.8, 0.8, 1.0)), (GL.GL_SPECULAR, (0.0, 0.0, 0.0, 1.0)), (GL.GL_EMISSION, (0.0, 0.0, 0.0, 1.0)), (GL.GL_SHININESS, 0)])

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