// Attributes attribute vec2 position; // Uniform uniform vec2 delta; // Output varying vec2 sampleCenter; #include[0..varyingCount] const vec2 madd = vec2(0.5, 0.5); void main(void) { sampleCenter = (position * madd + madd); #include[0..varyingCount] gl_Position = vec4(position, 0.0, 1.0); }