BLI: initial hash function for Color4b and float4x4

source/blender/blenlib/BLI_color.hh

@@ -118,6 +118,12 @@ struct Color4b {
   {
     return !(a == b);
   }
+
+  uint32_t hash() const
+  {
+    return ((uint32_t)r * 1283591) ^ ((uint32_t)g * 850177) ^ ((uint32_t)b * 735391) ^
+           ((uint32_t)a * 442319);
+  }
 };
 
 }  // namespace blender

source/blender/blenlib/BLI_float4x4.hh

@@ -108,6 +108,16 @@ struct float4x4 {
     interp_m4_m4m4(result, a.values, b.values, t);
     return result;
   }
+
+  uint32_t hash() const
+  {
+    uint32_t h = 435109;
+    for (uint i = 0; i < 16; i++) {
+      float value = ((const float *)this)[i];
+      h = h * 33 + (*(uint32_t *)&value);
+    }
+    return h;
+  }
 };
 
 }  // namespace blender