[Mesa-dev] llvmpipe and transform feedback of position

[Dave Airlie]

Hi,

So I've been playing around a bit more with transform feedback with
llvmpipe, and it seems the position output from the vertex shader is
different from what softpipe produces.

using from piglit ./bin/ext_transform_feedback-builtin-varyings gl_Position

the position with softpipe for the first call is
0	0.00390625	0.0078125	0.01171875
for llvmpipe it is
16	10.666666	0.833333373	85.3333359

so is there some intermediate storage or transform that isn't
happening in the llvm vertex shader, that should?

I start to realise how little I know about the vertex shading side of
things, when I hit stuff like this!

Dave.