Initial commit

glsl/random2.glsl

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+// Generate a pseudorandom 2D vector based on a 2D or 3D seed.
+//
+// https://thebookofshaders.com/edit.php#11/2d-gnoise.frag
+//
+// Inputs:
+//   st  2D seed
+// Returns 2D random point in [0,1]²
+vec2 random2(vec2 st){
+  st = vec2( dot(st,vec2(127.1,311.7)),
+             dot(st,vec2(269.5,183.3)) );
+  return fract(sin(st)*43758.5453123);
+}
+// Inputs:
+//   st  3D seed
+// Returns 2D random point in [0,1]²
+vec2 random2(vec3 st){
+  vec2 S = vec2( dot(st,vec3(127.1,311.7,783.089)),
+             dot(st,vec3(269.5,183.3,173.542)) );
+  return fract(sin(S)*43758.5453123);
+}
+