/usr/share/psychtoolbox-3/PsychGLImageProcessing/HookProcessingChains.m is in psychtoolbox-3-common 3.0.9+svn2579.dfsg1-1.
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1 2 3 4 5 6 7 | % HookProcessingChains - What they do, how to use them.
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% This is a list of Screen's builtin functions that can be used as
% processing slots in a hook chain of Screen:
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% 'Builtin:IdentityBlit' - Perform a (nearly) one-to-one blit of the input
% buffer into the output buffer, using
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