// A simple, circular vignette, with a cosĀ² falloff.
-
-uniform float PREFIX(inv_radius);
-uniform vec2 PREFIX(aspect_correction);
+
+// Implicit uniforms:
+// uniform float PREFIX(pihalf_div_radius);
+//
+// uniform vec2 PREFIX(aspect_correction);
+// uniform vec2 PREFIX(flipped_center);
vec4 FUNCNAME(vec2 tc) {
- vec4 x = LAST_INPUT(tc);
+ vec4 x = INPUT(tc);
const float pihalf = 0.5 * 3.14159265358979324;
- vec2 normalized_pos = (tc - PREFIX(center)) * PREFIX(aspect_correction);
- float dist = (length(normalized_pos) - PREFIX(inner_radius)) * PREFIX(inv_radius);
- float linear_falloff = clamp(dist, 0.0, 1.0) * pihalf;
+ 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);
x.rgb *= vec3(falloff);