Andrew Straw wrote: > I understand Martin's question to mean that he wants to modify the LUT > used by the RAMDAC in the video card. The shader route, or anything that > just alters what goes into the framebuffer, is probably not what he's > after. Instead, he's after how the framebuffer is interpreted. > > Digging through the SDL sources, it appears that for X11, the call is > XStoreColors. For Windows, SetDeviceGammaRamp. For Mac OS X Quartz, it's > CGSetDisplayTransferByTable. > > Hope that helps, > Andrew
Yeah, that's what I meant :) Andrew and I and many others use VisionEgg (which currently relies on pygame/SDL) for generating visual stimuli for use in psychophysics and neurophysiology. We often need to linearize the output of the display, so that a pixel value of 255 really is 255 times brighter (in candels/m^2, as measured by a light meter) than a pixel value of 1. We do this by gamma correction. I'm looking at extending VisionEgg to use pyglet as an alternative to pygame, so we can take advantage of multiple windows on multiple screens. It's been very easy so far, and gamma correction is about the only major thing I've found that's missing. Cheers, Martin --~--~---------~--~----~------------~-------~--~----~ You received this message because you are subscribed to the Google Groups "pyglet-users" group. To post to this group, send email to [email protected] To unsubscribe from this group, send email to [EMAIL PROTECTED] For more options, visit this group at http://groups.google.com/group/pyglet-users?hl=en -~----------~----~----~----~------~----~------~--~---
