Gradients are broken with glamor when RepeatReflect is set
chris at chris-wilson.co.uk
Tue Jan 23 17:24:35 UTC 2018
Quoting Clemens Eisserer (2018-01-23 17:03:04)
> Great to see movement regading this issue.
> > It's broken with llvmpipe/softpipe as well. Does it render correctly
> > with glamor on i965? If so, maybe it's a Gallium non-driver issue.
> Glamor on Intel Gen5 (Arrendale) procudes results consistent with
> So it seems the shader is the culprit.
Radial shader (which we think is correct):
t = abs(fract(t * 0.5 + 0.5) * 2.0 - 1.0);
Linear shader (note unnormalized):
distance = abs(mod(distance + _pt_distance, 2.0 * _pt_distance) - _pt_distance);
Which makes the same mistake as I did in using mod() instead of the GL
definition of fract(). Simplest fix will be to normalize distance and
then use the correct transformation from the radial shader.
More information about the xorg