- if (any(lessThan(tc, PREFIX(texcoord_min))) ||
- any(greaterThan(tc, PREFIX(texcoord_max)))) {
+ vec2 tc_texels = tc * PREFIX(normalized_coords_to_texels);
+ vec2 coverage_bottomleft = clamp(tc_texels + PREFIX(offset_bottomleft), 0.0f, 1.0f);
+ vec2 coverare_topright = clamp(PREFIX(offset_topright) - tc_texels, 0.0f, 1.0f);
+ vec2 coverage_both = coverage_bottomleft * coverare_topright;
+ float coverage = coverage_both.x * coverage_both.y;
+
+ if (coverage <= 0.0f) {
+ // Short-circuit in case the underlying function is expensive to call.