[Glamor] [PATCH 2/2] Add the feature of generating linear gradient picture using shader.

[Chris Wilson]

On Wed, 29 Feb 2012 07:23:57 +0800, junyan.he at linux.intel.com wrote:
> From: Junyan He <junyan.he at linux.intel.com>
> 
>  Add the feature of generating linear gradient picture by
>  using shader. This logic will replace the original
>  gradient picture generating manner in glamor which
>  firstly use pixman and then upload to GPU. Compare it
>  to the result generated by pixman, the difference of
>  each color of each pixel is normally 0, sometimes
>  1/255, and 2/255 at most. The pixman use fix int but
>  shader use float, so may have difference. There is just
>  one case that we will fallback. When the picture has
>  transform matrix and the matrix is a projective
>  matrix(which has non 0 at the third column and row.),
>  the shader's coordinate has been normalized and so it
>  is hard to work as what the pixman do. Some logic of
>  pixmap compare has been added to for easing the debug
>  of the pixmap generated by shader.

Need to handle RepeatPad and RepeatNone as well.
-Chris

-- 
Chris Wilson, Intel Open Source Technology Centre