[Openicc] Xorg low level buffers - colour conversion

[Kai-Uwe Behrmann]

Hello,

the recent thread, about a project for integrating colour management into 
X or placing it next to it, touched some technical aspects not clear to 
me.

My original idea was to link Oyranos into the composite manager. If I 
remember correctly Keith Packard suggested some years ago to run colour 
conversions there. This would allow to keep CMS code outside of the Xorg 
core. Beside this, I am not shure wheter X will be used in significant 
cases without a composite manager. Netherheless working code can provide a 
mature model to later decide upon.


Now, I have some questions related to some details, which will influence 
the design.


Control:
What kind of buffers can a Xorg composite manager cover? ... static screen 
content, Xvideo, OpenGL?
In other words, is the composite manager a key component to influence all 
colour paths to the screen at once?


Modularity:
Is it possibly to generalise GPU usage and run a shader programm over 
data residing in RAM?

Assuming that the shader programm is some thiny blob, would it be 
wise to provide this small programm by a CMM and thus influence the 
interpolation algorithm, e.g. make the shader generation plugable?

Is the GPU shader, generated by a CMM, useable on the early rendering end 
in a application?

Can a shader programm be written to files and shared by applications?

Has the final call, to bring this shader programm in place and start the 
colour conversion, realy influence on the result? Or is it more to see 
like a switch to start the programm?


So thats all. I hope my outsider questions still make sense to insiders.

kind regards
Kai-Uwe Behrmann
-- 
developing for colour management 
www.behrmann.name + www.oyranos.org