color management spec

Tomas Carnecky tom at
Fri May 30 08:28:38 PDT 2008

Maarten Maathuis wrote:
> On 5/30/08, Mikhail Gusarov <dottedmag at> wrote:
>> Twas brillig at 16:47:54 30.05.2008 UTC+02 when Tomas Carnecky did gyre and gimble:
>>  How do compositing and color management relate anyway? They are not, and
>>  entangling them like this looks like an unnatural (not to say pereverse)
>>  move.

When a compositing manager is running, all the windows are kept 
off-screen and, everytime the window contents change, the compmgr copies 
the frames to the frontbuffer. Compositing managers already use shaders 
for various effects, so sneaking one line of fragment shader comes at 
almost no additional cost.

> Even though it's probably possible, i suspect it'll be very slow. You
> really want to have the source adjust the colors, it's the best place
> to do it.

Applications would have to deal with much more then just 'adjusting the 
color'. The application would have to render first into an offscreen 
buffer and then copy the pixels to its window. So if you are running a 
compositing manager you would have two different buffers!


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