#!/usr/bin/env python
# -*- coding: utf-8 -*-
"""Window class for the NordicNeuralLab's VisualSystemHD(tm) fMRI display
system.
"""
# Part of the PsychoPy library
# Copyright (C) 2002-2018 Jonathan Peirce (C) 2019 Open Science Tools Ltd.
# Distributed under the terms of the GNU General Public License (GPL).
import ctypes
import numpy as np
import pyglet.gl as GL
from psychopy.visual import window
from psychopy import logging
import psychopy.tools.mathtools as mt
import psychopy.tools.viewtools as vt
import psychopy.tools.gltools as gt
try:
from PIL import Image
except ImportError:
import Image
reportNDroppedFrames = 5
# ------------------------------------------------------------------------------
# Configurations for the model of VSHD
#
vshdModels = {
'vshd': {
# store the configuration for FOV and viewing distance by diopters
'configByDiopters': {
-9: {'vfov': 29.70, 'dist': 0.111},
-8: {'vfov': 29.75, 'dist': 0.125},
-7: {'vfov': 29.8, 'dist': 0.143},
-6: {'vfov': 29.86, 'dist': 0.167},
-5: {'vfov': 29.92, 'dist': 0.20},
-4: {'vfov': 29.98, 'dist': 0.25},
-3: {'vfov': 30.04, 'dist': 0.333},
-2: {'vfov': 30.08, 'dist': 0.5},
-1: {'vfov': 30.14, 'dist': 1.0},
0: {'vfov': 30.18, 'dist': 1.0}, # TODO: handle this case
1: {'vfov': 30.24, 'dist': -1.0}, # image gets inverted
2: {'vfov': 30.3, 'dist': -0.5},
3: {'vfov': 30.36, 'dist': -0.333},
4: {'vfov': 30.42, 'dist': -0.25},
5: {'vfov': 30.46, 'dist': -0.2},
},
'scrHeightM': 9.6 * 1200. / 1e-6, # screen height in meters
'scrWidthM': 9.6 * 1920. / 1e-6, # screen width in meters
'distCoef': -0.02, # distortion coef. depends on screen size
'resolution': (1920, 1200) # resolution for the display per eye
}
}
# ------------------------------------------------------------------------------
# Window subclass class for VSHD hardware
#
[docs]
class VisualSystemHD(window.Window):
"""Class provides support for NordicNeuralLab's VisualSystemHD(tm) fMRI
display hardware. This is a lazy-imported class, therefore import using
full path `from psychopy.visual.nnlvs import VisualSystemHD` when
inheriting from it.
Use this class in-place of the `Window` class for use with the VSHD
hardware. Ensure that the VSHD headset display output is configured in
extended desktop mode (eg. nVidia Surround). Extended desktops are only
supported on Windows and Linux systems.
The VSHD is capable of both 2D and stereoscopic 3D rendering. You can select
which eye to draw to by calling `setBuffer`, much like how stereoscopic
rendering is implemented in the base `Window` class.
Notes
-----
* This class handles drawing differently than the default window class, as
a result, stimuli `autoDraw` is not supported.
* Edges of the warped image may appear jagged. To correct this, create a
window using `multiSample=True` and `numSamples > 1` to smooth out these
artifacts.
Examples
--------
Here is a basic example of 2D rendering using the VisualSystemHD(tm). This
is the binocular version of the dynamic 'plaid.py' demo::
from psychopy import visual, core, event
# Create a visual window
win = visual.VisualSystemHD(fullscr=True, screen=1)
# Initialize some stimuli, note contrast, opacity, ori
grating1 = visual.GratingStim(win, mask="circle", color='white',
contrast=0.5, size=(1.0, 1.0), sf=(4, 0), ori = 45, autoLog=False)
grating2 = visual.GratingStim(win, mask="circle", color='white',
opacity=0.5, size=(1.0, 1.0), sf=(4, 0), ori = -45, autoLog=False,
pos=(0.1, 0.1))
trialClock = core.Clock()
t = 0
while not event.getKeys() and t < 20:
t = trialClock.getTime()
for eye in ('left', 'right'):
win.setBuffer(eye) # change the buffer
grating1.phase = 1 * t # drift at 1Hz
grating1.draw() # redraw it
grating2.phase = 2 * t # drift at 2Hz
grating2.draw() # redraw it
win.flip()
win.close()
core.quit()
As you can see above, there are few changes needed to convert an existing 2D
experiment to run on the VSHD. For 3D rendering with perspective, you need
set `eyeOffset` and apply the projection by calling `setPerspectiveView`.
(other projection modes are not implemented or supported right now)::
from psychopy import visual, core, event
# Create a visual window
win = visual.VisualSystemHD(fullscr=True, screen=1,
multiSample=True, nSamples=8)
# text to display
instr = visual.TextStim(win, text="Any key to quit", pos=(0, -.7))
# create scene light at the pivot point
win.lights = [
visual.LightSource(win, pos=(0.4, 4.0, -2.0), lightType='point',
diffuseColor=(0, 0, 0), specularColor=(1, 1, 1))
]
win.ambientLight = (0.2, 0.2, 0.2)
# Initialize some stimuli, note contrast, opacity, ori
ball = visual.SphereStim(win, radius=0.1, pos=(0, 0, -2), color='green',
useShaders=False)
iod = 6.2 # interocular separation in CM
win.setEyeOffset(-iod / 2.0, 'left')
win.setEyeOffset(iod / 2.0, 'right')
trialClock = core.Clock()
t = 0
while not event.getKeys() and t < 20:
t = trialClock.getTime()
for eye in ('left', 'right'):
win.setBuffer(eye) # change the buffer
# setup drawing with perspective
win.setPerspectiveView()
win.useLights = True # switch on lights
ball.draw() # draw the ball
# shut the lights, needed to prevent light color from affecting
# 2D stim
win.useLights = False
# reset transform to draw text correctly
win.resetEyeTransform()
instr.draw()
win.flip()
win.close()
core.quit()
"""
def __init__(self, monoscopic=False, diopters=(-1, -1), lensCorrection=True,
distCoef=None, directDraw=False, model='vshd', *args,
**kwargs):
"""
Parameters
----------
monoscopic : bool
Use monoscopic rendering. If `True`, the same image will be drawn to
both eye buffers. You will not need to call `setBuffer`. It is not
possible to set monoscopic mode after the window is created. It is
recommended that you use monoscopic mode if you intend to display
only 2D stimuli about the center of the display as it uses a less
memory intensive rendering pipeline.
diopters : tuple or list
Initial diopter values for the left and right eye. Default is
`(-1, -1)`, values must be integers.
lensCorrection : bool
Apply lens correction (barrel distortion) to the output. The amount
of distortion applied can be specified using `distCoef`. If `False`,
no distortion will be applied to the output and the entire display
will be used. Not applying correction will result in pincushion
distortion which produces a non-rectilinear output.
distCoef : float
Distortion coefficient for barrel distortion. If `None`, the
recommended value will be used for the model of display. You can
adjust the value to fine-tune the barrel distortion.
directDraw : bool
Direct drawing mode. Stimuli are drawn directly to the back buffer
instead of creating separate buffer. This saves video memory but
does not permit barrel distortion or monoscopic rendering. If
`False`, drawing is done with two FBOs containing each eye's image.
hwModel : str
Model of the VisualSystemHD in use. Used to set viewing parameters
accordingly. Default is 'vshd'. Cannot be changed after starting the
application.
"""
# warn if given `useFBO`
if kwargs.get('useFBO', False):
logging.warning(
"Creating a window with `useFBO` is not recommended.")
# call up a new window object
super(VisualSystemHD, self).__init__(*args, **kwargs)
# direct draw mode
self._directDraw = directDraw
# is monoscopic mode enabled?
self._monoscopic = monoscopic and not self._directDraw
self._lensCorrection = lensCorrection and not self._directDraw
# hardware information for a given model of the display, used for
# configuration
self._hwModel = model
self._hwDesc = vshdModels[self._hwModel]
# distortion coefficient
self._distCoef = \
self._hwDesc['distCoef'] if distCoef is None else float(distCoef)
# diopter settings for each eye, needed to compute actual FOV
self._diopters = {'left': diopters[0], 'right': diopters[1]}
# eye offsets, this will be standard when multi-buffer rendering gets
# implemented in the main window class
self._eyeOffsets = {'left': -3.1, 'right': 3.1}
# look-up table of FOV values for each diopter setting
self._fovLUT = self._hwDesc['configByDiopters']
# get the dimensions of the buffer for each eye
bufferWidth, bufferHieght = self.frameBufferSize
bufferWidth = int(bufferWidth / 2.0)
# viewports for each buffer
self._bufferViewports = dict()
self._bufferViewports['left'] = (0, 0, bufferWidth, bufferHieght)
self._bufferViewports['right'] = \
(bufferWidth if self._directDraw else 0,
0, bufferWidth, bufferHieght)
self._bufferViewports['back'] = \
(0, 0, self.frameBufferSize[0], self.frameBufferSize[1])
# create render targets for each eye buffer
self.buffer = None
self._eyeBuffers = dict()
# VAOs for distortion mesh
self._warpVAOs = dict()
# extents of the barrel distortion needed to compute FOV after
# distortion
self._distExtents = {
'left': np.array([[-1, 0], [1, 0], [0, 1], [0, -1]]),
'right': np.array([[-1, 0], [1, 0], [0, 1], [0, -1]])
}
# if we are using an FBO, keep a reference to its handles
if self.useFBO:
self._eyeBuffers['back'] = {
'frameBuffer': self.frameBuffer,
'frameTexture': self.frameTexture,
'frameStencil': self._stencilTexture}
self._setupEyeBuffers() # setup additional framebuffers
self._setupLensCorrection() # setup lens correction meshes
self.setBuffer('left') # set to the back buffer on start
@property
def monoscopic(self):
"""`True` if using monoscopic mode."""
return self._monoscopic
@property
def lensCorrection(self):
"""`True` if using lens correction."""
return self._lensCorrection
@lensCorrection.setter
def lensCorrection(self, value):
self._lensCorrection = value
@property
def distCoef(self):
"""Distortion coefficient (`float`)."""
return self._distCoef
@distCoef.setter
def distCoef(self, value):
if isinstance(value, (float, int,)):
self._distCoef = float(value)
elif value is None:
self._distCoef = self._hwDesc['distCoef']
else:
raise ValueError('Invalid value for `distCoef`.')
self._setupLensCorrection() # deletes old VAOs
@property
def diopters(self):
"""Diopters value of the current eye buffer."""
return self._diopters[self.buffer]
@diopters.setter
def diopters(self, value):
self.setDiopters(value)
[docs]
def setDiopters(self, diopters, eye=None):
"""Set the diopters for a given eye.
Parameters
----------
diopters : int
Set diopters for a given eye, ranging between -7 and +5.
eye : str or None
Eye to set, either 'left' or 'right'. If `None`, the currently
set buffer will be used.
"""
eye = self.buffer if eye is None else eye
# check if diopters value in config
if diopters not in self._hwDesc['configByDiopters'].keys():
raise ValueError("Diopter setting invalid for display model.")
try:
self._diopters[eye] = int(diopters)
except KeyError:
raise ValueError(
"Invalid `eye` specified, must be 'left' or 'right'.")
@property
def eyeOffset(self):
"""Eye offset for the current buffer in centimeters used for
stereoscopic rendering. This works differently than the main window
class as it sets the offset for the current buffer. The offset is saved
and automatically restored when the buffer is selected.
"""
return self._eyeOffsets[self.buffer] * 100. # to centimeters
@eyeOffset.setter
def eyeOffset(self, value):
self._eyeOffsets[self.buffer] = float(value) / 100. # to meters
[docs]
def setEyeOffset(self, dist, eye=None):
"""Set the eye offset in centimeters.
When set, successive rendering operations will use the new offset.
Parameters
----------
dist : float or int
Lateral offset in centimeters from the nose, usually half the
interocular separation. The distance is signed.
eye : str or None
Eye offset to set. Can either be 'left', 'right' or `None`. If
`None`, the offset of the current buffer is used.
"""
eye = self.buffer if eye is None else eye
try:
self._eyeOffsets[eye] = float(dist) / 100. # to meters
except KeyError:
raise ValueError(
"Invalid `eye` specified, must be 'left' or 'right'.")
# def _getFocalLength(self, eye=None):
# """Get the focal length for a given `eye` in meters.
#
# Parameters
# ----------
# eye : str or None
# Eye to use, either 'left' or 'right'. If `None`, the currently
# set buffer will be used.
#
# """
# try:
# focalLength = 1. / self._diopters[eye]
# except KeyError:
# raise ValueError(
# "Invalid value for `eye`, must be 'left' or 'right'.")
# except ZeroDivisionError:
# raise ValueError("Value for diopters cannot be zero.")
#
# return focalLength
#
# def _getMagFactor(self, eye=None):
# """Get the magnification factor of the lens for a given eye. Used to
# in part to compute the actual size of the object.
#
# Parameters
# ----------
# eye : str or None
# Eye to use, either 'left' or 'right'. If `None`, the currently
# set buffer will be used.
#
# """
# eye = self.buffer if eye is None else eye
# return (self._diopters[eye] / 4.) + 1.
#
# def _getScreenFOV(self, eye, direction='horizontal', degrees=True):
# """Compute the FOV of the display."""
# if direction not in ('horizontal', 'vertical'):
# raise ValueError("Invalid `direction` specified, must be "
# "'horizontal' or 'vertical'.")
#
# # todo: figure this out
#
# def _getPredictedFOV(self, size, eye=None):
# """Get the predicted vertical FOV of the display for a given eye.
#
# Parameters
# ----------
# size : float
# Size of the object on screen in meters.
# eye : str or None
# Eye to use, either 'left' or 'right'. If `None`, the currently
# set buffer will be used.
#
# """
# return np.degrees(2. * np.arctan(size / (2. * self._getFocalLength(eye))))
#
# def _getActualFOV(self, size, eye=None):
# """Get the actual FOV of an object of `size` for a given eye."""
# if eye not in ('left', 'right'):
# raise ValueError(
# "Invalid value for `eye`, must be 'left' or 'right'.")
#
# # predFOV = self._getPredictedFOV(size, eye)
# actualFOV = 0.0098 * size ** 3 - 0.0576 * size ** 2 + 2.6728 * size - 0.0942
#
# return actualFOV
#
# def getDistortion(self, size, eye=None):
# """Get the optical distortion amount (percent) for a stimulus of given
# `size` in degrees positioned at the center of the display."""
# predFOV = self._getPredictedFOV(size, eye)
# actualFOV = self._getActualFOV(size, eye)
#
# return ((actualFOV - predFOV) * predFOV) * 100.
[docs]
def _getWarpExtents(self, eye):
"""Get the horizontal and vertical extents of the barrel distortion in
normalized device coordinates. This is used to determine the FOV along
each axis after barrel distortion.
Parameters
----------
eye : str
Eye to compute the extents for.
Returns
-------
ndarray
2d array of coordinates [+X, -X, +Y, -Y] of the extents of the
barrel distortion.
"""
coords = np.array([
[-1.0, 0.0],
[ 1.0, 0.0],
[ 0.0, 1.0],
[ 0.0, -1.0]])
try:
bufferW, bufferH = self._bufferViewports[eye][2:]
except KeyError:
raise ValueError("Invalid eye buffer specified.")
warpedCoords = mt.lensCorrectionSpherical(
coords, self._distCoef, bufferW / bufferH)
return warpedCoords
[docs]
def _setupLensCorrection(self):
"""Setup the VAOs needed for lens correction.
"""
# don't create warp mesh if direct draw enabled
if self._directDraw:
return
# clean up previous distortion data
if self._warpVAOs:
for vao in self._warpVAOs.values():
gt.deleteVAO(vao)
self._warpVAOs = {}
for eye in ('left', 'right'):
# setup vertex arrays for the output quad
bufferW, bufferH = self._bufferViewports[eye][2:]
aspect = bufferW / bufferH
vertices, texCoord, normals, faces = gt.createMeshGrid(
(2.0, 2.0), subdiv=256, tessMode='radial')
# recompute vertex positions
vertices[:, :2] = mt.lensCorrectionSpherical(
vertices[:, :2], coefK=self.distCoef, aspect=aspect)
# create the VAO for the eye buffer
vertexVBO = gt.createVBO(vertices, usage=GL.GL_DYNAMIC_DRAW)
texCoordVBO = gt.createVBO(texCoord, usage=GL.GL_DYNAMIC_DRAW)
indexBuffer = gt.createVBO(
faces.flatten(),
target=GL.GL_ELEMENT_ARRAY_BUFFER,
dataType=GL.GL_UNSIGNED_INT)
attribBuffers = {GL.GL_VERTEX_ARRAY: vertexVBO,
GL.GL_TEXTURE_COORD_ARRAY: texCoordVBO}
self._warpVAOs[eye] = gt.createVAO(attribBuffers,
indexBuffer=indexBuffer,
legacy=True)
# get the extents of the warping
self._distExtents[eye] = self._getWarpExtents(eye)
[docs]
def _setupEyeBuffers(self):
"""Setup additional buffers for rendering content to each eye.
"""
if self._directDraw: # don't create additional buffers is direct draw
return
def createFramebuffer(width, height):
"""Function for setting up additional buffer"""
# create a new framebuffer
fboId = GL.GLuint()
GL.glGenFramebuffers(1, ctypes.byref(fboId))
GL.glBindFramebuffer(GL.GL_FRAMEBUFFER, fboId)
# create a texture to render to, required for warping
texId = GL.GLuint()
GL.glGenTextures(1, ctypes.byref(texId))
GL.glBindTexture(GL.GL_TEXTURE_2D, texId)
GL.glTexParameteri(GL.GL_TEXTURE_2D,
GL.GL_TEXTURE_MAG_FILTER,
GL.GL_LINEAR)
GL.glTexParameteri(GL.GL_TEXTURE_2D,
GL.GL_TEXTURE_MIN_FILTER,
GL.GL_LINEAR)
GL.glTexImage2D(GL.GL_TEXTURE_2D, 0, GL.GL_RGBA32F_ARB,
int(width), int(height), 0,
GL.GL_RGBA, GL.GL_FLOAT, None)
GL.glFramebufferTexture2D(GL.GL_FRAMEBUFFER,
GL.GL_COLOR_ATTACHMENT0,
GL.GL_TEXTURE_2D,
texId,
0)
# create a render buffer
rbId = GL.GLuint()
GL.glGenRenderbuffers(1, ctypes.byref(rbId))
GL.glBindRenderbuffer(GL.GL_RENDERBUFFER, rbId)
GL.glRenderbufferStorage(
GL.GL_RENDERBUFFER,
GL.GL_DEPTH24_STENCIL8,
int(width),
int(height))
GL.glFramebufferRenderbuffer(
GL.GL_FRAMEBUFFER,
GL.GL_DEPTH_ATTACHMENT,
GL.GL_RENDERBUFFER,
rbId)
GL.glFramebufferRenderbuffer(
GL.GL_FRAMEBUFFER,
GL.GL_STENCIL_ATTACHMENT,
GL.GL_RENDERBUFFER,
rbId)
GL.glBindRenderbuffer(GL.GL_RENDERBUFFER, 0)
# clear the buffer
GL.glClear(GL.GL_COLOR_BUFFER_BIT)
GL.glClear(GL.GL_STENCIL_BUFFER_BIT)
GL.glClear(GL.GL_DEPTH_BUFFER_BIT)
GL.glBindFramebuffer(GL.GL_FRAMEBUFFER, 0)
return fboId, texId, rbId
if not self._monoscopic:
# create eye buffers
for eye in ('left', 'right'):
# get dimensions of required buffer
bufferW, bufferH = self._bufferViewports[eye][2:]
fboId, texId, rbId = createFramebuffer(bufferW, bufferH)
# add new buffers
self._eyeBuffers[eye] = {
'frameBuffer': fboId,
'frameTexture': texId,
'frameStencil': rbId}
else:
# only the left eye buffer is created
bufferW, bufferH = self._bufferViewports['left'][2:]
fboId, texId, rbId = createFramebuffer(bufferW, bufferH)
self._eyeBuffers['left'] = {
'frameBuffer': fboId,
'frameTexture': texId,
'frameStencil': rbId}
self._eyeBuffers['right'] = self._eyeBuffers['left']
[docs]
def setBuffer(self, buffer, clear=True):
"""Set the eye buffer to draw to. Subsequent draw calls will be diverted
to the specified eye.
Parameters
----------
buffer : str
Eye buffer to draw to. Values can either be 'left' or 'right'.
clear : bool
Clear the buffer prior to drawing.
"""
# check if the buffer name is valid
if buffer not in ('left', 'right', 'back'):
raise RuntimeError("Invalid buffer name specified.")
# don't change the buffer if same, but allow clearing
if buffer != self.buffer:
if not self._directDraw:
# handle when the back buffer is selected
if buffer == 'back':
if self.useFBO:
GL.glBindFramebuffer(
GL.GL_FRAMEBUFFER,
self._eyeBuffers[buffer]['frameBuffer'])
else:
GL.glBindFramebuffer(GL.GL_FRAMEBUFFER, 0)
else:
GL.glBindFramebuffer(
GL.GL_FRAMEBUFFER, self._eyeBuffers[buffer]['frameBuffer'])
self.viewport = self.scissor = self._bufferViewports[buffer]
GL.glEnable(GL.GL_SCISSOR_TEST)
self.buffer = buffer # set buffer string
if clear:
self.setColor(self.color) # clear the buffer to the window color
GL.glClearDepth(1.0)
GL.glDepthMask(GL.GL_TRUE)
GL.glClear(
GL.GL_COLOR_BUFFER_BIT |
GL.GL_DEPTH_BUFFER_BIT |
GL.GL_STENCIL_BUFFER_BIT)
GL.glDisable(GL.GL_TEXTURE_2D)
GL.glEnable(GL.GL_BLEND)
[docs]
def setPerspectiveView(self, applyTransform=True, clearDepth=True):
"""Set the projection and view matrix to render with perspective.
Matrices are computed using values specified in the monitor
configuration with the scene origin on the screen plane. Calculations
assume units are in meters. If `eyeOffset != 0`, the view will be
transformed laterally, however the frustum shape will remain the
same.
Note that the values of :py:attr:`~Window.projectionMatrix` and
:py:attr:`~Window.viewMatrix` will be replaced when calling this
function.
Parameters
----------
applyTransform : bool
Apply transformations after computing them in immediate mode. Same
as calling :py:attr:`~Window.applyEyeTransform()` afterwards if
`False`.
clearDepth : bool, optional
Clear the depth buffer.
"""
# Not in full screen mode? Need to compute the dimensions of the display
# area to ensure disparities are correct even when in windowed-mode.
aspect = self.size[0] / self.size[1]
# use these instead of those from the monitor configuration
vfov = self._fovLUT[self._diopters[self.buffer]]['vfov']
scrDist = self._fovLUT[self._diopters[self.buffer]]['dist']
frustum = vt.computeFrustumFOV(
vfov,
aspect, # aspect ratio
scrDist,
nearClip=self._nearClip,
farClip=self._farClip)
self._projectionMatrix = \
vt.perspectiveProjectionMatrix(*frustum, dtype=np.float32)
# translate away from screen
self._viewMatrix = np.identity(4, dtype=np.float32)
self._viewMatrix[0, 3] = -self._eyeOffsets[self.buffer] # apply eye offset
self._viewMatrix[2, 3] = -scrDist # displace scene away from viewer
if applyTransform:
self.applyEyeTransform(clearDepth=clearDepth)
[docs]
def _blitEyeBuffer(self, eye):
"""Warp and blit to the appropriate eye buffer.
Parameters
----------
eye : str
Eye buffer being used.
"""
GL.glBindTexture(GL.GL_TEXTURE_2D,
self._eyeBuffers[eye]['frameTexture'])
GL.glEnable(GL.GL_SCISSOR_TEST)
# set the viewport and scissor rect for the buffer
frameW, frameH = self._bufferViewports[eye][2:]
offset = 0 if eye == 'left' else frameW
self.viewport = self.scissor = (offset, 0, frameW, frameH)
if self.USE_LEGACY_GL:
GL.glMatrixMode(GL.GL_PROJECTION)
GL.glLoadIdentity()
GL.glOrtho(-1, 1, -1, 1, -1, 1)
GL.glMatrixMode(GL.GL_MODELVIEW)
GL.glLoadIdentity()
# anti-aliasing the edges of the polygon
GL.glEnable(GL.GL_MULTISAMPLE)
# blit the quad covering the side of the display the eye is viewing
if self.lensCorrection:
gt.drawVAO(self._warpVAOs[eye])
else:
self._renderFBO()
GL.glDisable(GL.GL_MULTISAMPLE)
# reset
GL.glDisable(GL.GL_SCISSOR_TEST)
self.viewport = self.scissor = \
(0, 0, self.frameBufferSize[0], self.frameBufferSize[1])
[docs]
def _startOfFlip(self):
"""Custom :py:class:`~Rift._startOfFlip` for HMD rendering. This
finalizes the HMD texture before diverting drawing operations back to
the on-screen window. This allows :py:class:`~Rift.flip` to swap the
on-screen and HMD buffers when called. This function always returns
`True`.
Returns
-------
True
"""
# nop if we are still setting up the window
if not hasattr(self, '_eyeBuffers'):
return True
# direct draw being used, don't do FBO blit
if self._directDraw:
return True
# Switch off multi-sampling
# GL.glDisable(GL.GL_MULTISAMPLE)
oldColor = self.color
self.setColor((-1, -1, -1))
self.setBuffer('back', clear=True)
self._prepareFBOrender()
# need blit the framebuffer object to the actual back buffer
# unbind the framebuffer as the render target
GL.glDisable(GL.GL_BLEND)
stencilOn = self.stencilTest
self.stencilTest = False
# before flipping need to copy the renderBuffer to the
# frameBuffer
GL.glActiveTexture(GL.GL_TEXTURE0)
GL.glEnable(GL.GL_TEXTURE_2D)
if self.USE_LEGACY_GL:
GL.glColor3f(1.0, 1.0, 1.0) # glColor multiplies with texture
GL.glColorMask(True, True, True, True)
# blit the textures to the back buffer
for eye in ('left', 'right'):
self._blitEyeBuffer(eye)
GL.glEnable(GL.GL_BLEND)
self._finishFBOrender()
self.stencilTest = stencilOn
self.setColor(oldColor)
# This always returns True
return True
[docs]
def _endOfFlip(self, clearBuffer):
"""Override end of flip with custom color channel masking if required.
"""
if clearBuffer:
GL.glClear(GL.GL_COLOR_BUFFER_BIT)
# nop if we are still setting up the window
if hasattr(self, '_eyeBuffers'):
self.setBuffer('left', clear=clearBuffer)
if __name__ == "__main__":
pass
