init

Assets/Pixel3D/Shaders/Random.cginc

@@ -0,0 +1,32 @@
+uint rng_state;
+
+//Hash invented by Thomas Wang
+void wang_hash(uint seed) {
+    rng_state = (seed ^ 61) ^ (seed >> 16);
+    rng_state *= 9;
+    rng_state = rng_state ^ (rng_state >> 4);
+    rng_state *= 0x27d4eb2d;
+    rng_state = rng_state ^ (rng_state >> 15);
+}
+
+//Xorshift algorithm from George Marsaglia's paper
+uint rand_xorshift() {
+    rng_state ^= (rng_state << 13);
+    rng_state ^= (rng_state >> 17);
+    rng_state ^= (rng_state << 5);
+
+    return rng_state;
+}
+
+float randValue() {
+    return rand_xorshift() * (1.0 / 4294967296.0);
+}
+
+void initRand(uint seed) {
+    wang_hash(seed);
+}
+
+float randValue(uint seed) {
+    initRand(seed);
+    return randValue();
+}