1 files changed, 217 insertions, 0 deletions
diff --git a/source/blender/gpu/shaders/material/gpu_shader_material_hash.glsl b/source/blender/gpu/shaders/material/gpu_shader_material_hash.glsl
new file mode 100644
index 00000000000..86191451e5f
--- /dev/null
+++ b/source/blender/gpu/shaders/material/gpu_shader_material_hash.glsl
@@ -0,0 +1,217 @@
+/* ***** Jenkins Lookup3 Hash Functions ***** */
+
+/* Source: http://burtleburtle.net/bob/c/lookup3.c */
+
+#define rot(x, k) (((x) << (k)) | ((x) >> (32 - (k))))
+
+#define mix(a, b, c) \
+  { \
+    a -= c; \
+    a ^= rot(c, 4); \
+    c += b; \
+    b -= a; \
+    b ^= rot(a, 6); \
+    a += c; \
+    c -= b; \
+    c ^= rot(b, 8); \
+    b += a; \
+    a -= c; \
+    a ^= rot(c, 16); \
+    c += b; \
+    b -= a; \
+    b ^= rot(a, 19); \
+    a += c; \
+    c -= b; \
+    c ^= rot(b, 4); \
+    b += a; \
+  }
+
+#define final(a, b, c) \
+  { \
+    c ^= b; \
+    c -= rot(b, 14); \
+    a ^= c; \
+    a -= rot(c, 11); \
+    b ^= a; \
+    b -= rot(a, 25); \
+    c ^= b; \
+    c -= rot(b, 16); \
+    a ^= c; \
+    a -= rot(c, 4); \
+    b ^= a; \
+    b -= rot(a, 14); \
+    c ^= b; \
+    c -= rot(b, 24); \
+  }
+
+uint hash_uint(uint kx)
+{
+  uint a, b, c;
+  a = b = c = 0xdeadbeefu + (1u << 2u) + 13u;
+
+  a += kx;
+  final(a, b, c);
+
+  return c;
+}
+
+uint hash_uint2(uint kx, uint ky)
+{
+  uint a, b, c;
+  a = b = c = 0xdeadbeefu + (2u << 2u) + 13u;
+
+  b += ky;
+  a += kx;
+  final(a, b, c);
+
+  return c;
+}
+
+uint hash_uint3(uint kx, uint ky, uint kz)
+{
+  uint a, b, c;
+  a = b = c = 0xdeadbeefu + (3u << 2u) + 13u;
+
+  c += kz;
+  b += ky;
+  a += kx;
+  final(a, b, c);
+
+  return c;
+}
+
+uint hash_uint4(uint kx, uint ky, uint kz, uint kw)
+{
+  uint a, b, c;
+  a = b = c = 0xdeadbeefu + (4u << 2u) + 13u;
+
+  a += kx;
+  b += ky;
+  c += kz;
+  mix(a, b, c);
+
+  a += kw;
+  final(a, b, c);
+
+  return c;
+}
+
+#undef rot
+#undef final
+#undef mix
+
+uint hash_int(int kx)
+{
+  return hash_uint(uint(kx));
+}
+
+uint hash_int2(int kx, int ky)
+{
+  return hash_uint2(uint(kx), uint(ky));
+}
+
+uint hash_int3(int kx, int ky, int kz)
+{
+  return hash_uint3(uint(kx), uint(ky), uint(kz));
+}
+
+uint hash_int4(int kx, int ky, int kz, int kw)
+{
+  return hash_uint4(uint(kx), uint(ky), uint(kz), uint(kw));
+}
+
+/* Hashing uint or uint[234] into a float in the range [0, 1]. */
+
+float hash_uint_to_float(uint kx)
+{
+  return float(hash_uint(kx)) / float(0xFFFFFFFFu);
+}
+
+float hash_uint2_to_float(uint kx, uint ky)
+{
+  return float(hash_uint2(kx, ky)) / float(0xFFFFFFFFu);
+}
+
+float hash_uint3_to_float(uint kx, uint ky, uint kz)
+{
+  return float(hash_uint3(kx, ky, kz)) / float(0xFFFFFFFFu);
+}
+
+float hash_uint4_to_float(uint kx, uint ky, uint kz, uint kw)
+{
+  return float(hash_uint4(kx, ky, kz, kw)) / float(0xFFFFFFFFu);
+}
+
+/* Hashing float or vec[234] into a float in the range [0, 1]. */
+
+float hash_float_to_float(float k)
+{
+  return hash_uint_to_float(floatBitsToUint(k));
+}
+
+float hash_vec2_to_float(vec2 k)
+{
+  return hash_uint2_to_float(floatBitsToUint(k.x), floatBitsToUint(k.y));
+}
+
+float hash_vec3_to_float(vec3 k)
+{
+  return hash_uint3_to_float(floatBitsToUint(k.x), floatBitsToUint(k.y), floatBitsToUint(k.z));
+}
+
+float hash_vec4_to_float(vec4 k)
+{
+  return hash_uint4_to_float(
+      floatBitsToUint(k.x), floatBitsToUint(k.y), floatBitsToUint(k.z), floatBitsToUint(k.w));
+}
+
+/* Hashing vec[234] into vec[234] of components in the range [0, 1]. */
+
+vec2 hash_vec2_to_vec2(vec2 k)
+{
+  return vec2(hash_vec2_to_float(k), hash_vec3_to_float(vec3(k, 1.0)));
+}
+
+vec3 hash_vec3_to_vec3(vec3 k)
+{
+  return vec3(
+      hash_vec3_to_float(k), hash_vec4_to_float(vec4(k, 1.0)), hash_vec4_to_float(vec4(k, 2.0)));
+}
+
+vec4 hash_vec4_to_vec4(vec4 k)
+{
+  return vec4(hash_vec4_to_float(k.xyzw),
+              hash_vec4_to_float(k.wxyz),
+              hash_vec4_to_float(k.zwxy),
+              hash_vec4_to_float(k.yzwx));
+}
+
+/* Hashing float or vec[234] into vec3 of components in range [0, 1]. */
+
+vec3 hash_float_to_vec3(float k)
+{
+  return vec3(
+      hash_float_to_float(k), hash_vec2_to_float(vec2(k, 1.0)), hash_vec2_to_float(vec2(k, 2.0)));
+}
+
+vec3 hash_vec2_to_vec3(vec2 k)
+{
+  return vec3(
+      hash_vec2_to_float(k), hash_vec3_to_float(vec3(k, 1.0)), hash_vec3_to_float(vec3(k, 2.0)));
+}
+
+vec3 hash_vec4_to_vec3(vec4 k)
+{
+  return vec3(hash_vec4_to_float(k.xyzw), hash_vec4_to_float(k.zxwy), hash_vec4_to_float(k.wzyx));
+}
+
+/* Other Hash Functions */
+
+float integer_noise(int n)
+{
+  int nn;
+  n = (n + 1013) & 0x7fffffff;
+  n = (n >> 13) ^ n;
+  nn = (n * (n * n * 60493 + 19990303) + 1376312589) & 0x7fffffff;
+  return 0.5 * (float(nn) / 1073741824.0);
+}