--- /dev/null
+// A simple, circular vignette, with a cosĀ² falloff.
+
+uniform float PREFIX(inv_radius);
+uniform vec2 PREFIX(aspect_correction);
+
+vec4 FUNCNAME(vec2 tc) {
+ vec4 x = LAST_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;
+ float falloff = cos(linear_falloff) * cos(linear_falloff);
+ x.rgb *= vec3(falloff);
+
+ return x;
+}