Does anyone know who to interpolate UVs in a quad tessellation evaluation shader? I can interpolate the position easily like so :
vec4 p1 = mix(gl_in.gl_Position, gl_in.gl_Position, gl_TessCoord.x); vec4 p2 = mix(gl_in.gl_Position, gl_in.gl_Position, gl_TessCoord.x); gl_Position = mix(p2, p1, gl_TessCoord.y);
But I can't figure out how to interpolate the incoming UV coordinates. I need to do so to pass them on to the fragment shader.
With perfect quad UVs from 0 to 1, I can use
gl_TessCoord.xy. Unfortunately that doesn't work when the UVs aren't mapped 1:1 to a texture.