When packing 2D texture coordinates in the float4 Texcoords I noticed a driver bug in my ATI driver (8.2).
I calc the texcoords for filter kernel in vertexshader and pass pairs in xy and zw. The same code works for 2D texture fetches.
# this instruction doesnt work, only in 2D mode TEX result.color, fragment.texcoord.zwzw, texture, RECT; # the workaround is accepted, but not practical MOV R0, fragment.texcoord.zwzw; MUL R0.zw, R0, 0; TEX result.color, R0, texture, RECT;
another workaround would be passing each texcoord in dedicated interpolant, or do the offsets in the fragment shader also.
just wondering if anyone can confirm this.
And if there is some email address to best-send ogl related driver bugs to AMD?