uniform float PREFIX(pihalf_div_radius);
uniform vec2 PREFIX(aspect_correction);
+uniform vec2 PREFIX(flipped_center);
vec4 FUNCNAME(vec2 tc) {
vec4 x = INPUT(tc);
const float pihalf = 0.5 * 3.14159265358979324;
- vec2 normalized_pos = (tc - PREFIX(center)) * PREFIX(aspect_correction);
+ vec2 normalized_pos = (tc - PREFIX(flipped_center)) * PREFIX(aspect_correction);
float dist = (length(normalized_pos) - PREFIX(inner_radius)) * PREFIX(pihalf_div_radius);
float linear_falloff = clamp(dist, 0.0, pihalf);
float falloff = cos(linear_falloff) * cos(linear_falloff);