gpir basic conditional support
Created by: enunes
Implement 'less-than' and 'select' alu opcodes. Tested with gbm-surface and the following silly vertex shader:
attribute vec3 positionIn;
void main()
{
vec3 myvar = positionIn;
if (positionIn.x > 0.1)
myvar.y = 0.8;
gl_Position = vec4(myvar, 1);
}
It causes the rightmost edge of the gbm-surface triangle to have its y-coordinate modified.