psychopy.tools.gltools.createFBO

psychopy.tools.gltools.createFBO(attachments=())[source]

Create a Framebuffer Object.

Parameters

attachments (list or tuple of 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 descriptor.

Return type

Framebuffer

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

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