Bug report: HLSL transformations with Atom Z2760, GMA
A customer of our reported a problem with a tablet Acer Iconia W3, and said graphics are not shown in correct place. We bought similar device and verfied the problem exists. Driver version is 188.8.131.528
Note that our software has worked fine in all other computers, and there's thousands of those amongst the users. All AMD GPUs work correctly, all Nvidias, and all Intel HDs as well.
This is AMD's rendering result, which is all OK.
With the Atom device, the HLSL vertex shader transformed colorful spectrogram surface is in wrong place and in many cases much farther away or badly distorted.
By running the software with REFERENCE rasterizer, it renders correctly with the Atom as well.
The axes, floor and text transformations are made with DirectX 9's built-in rendering pipeline. Color spectrogram surface instead has been made with HLSL. In vertex shader we transform the coordinates:
vout.Pos_ps = mul(position, WorldViewProjection); //WorldViewProjection has all transformations
This seems like a very bad floating point precision thing with this Atom, and figuring this is probably a driver bug.