Merge remote-tracking branch 'origin/main' into DRTVWR-559

1 files changed, 26 insertions, 0 deletions

diff --git a/indra/llprimitive/llmaterialid.h b/indra/llprimitive/llmaterialid.h
index e6165dfc91..5eb463b0fd 100644
--- a/indra/llprimitive/llmaterialid.h
+++ b/indra/llprimitive/llmaterialid.h
@@ -67,6 +67,14 @@ public:
 
 	static const LLMaterialID null;
 
+	// Returns a 64 bits digest of the material Id, by XORing its two 64 bits
+	// long words. HB
+	inline U64 getDigest64() const
+	{
+		U64* tmp = (U64*)mID;
+		return tmp[0] ^ tmp[1];
+	}
+
 private:
 	void parseFromBinary(const LLSD::Binary& pMaterialID);
 	void copyFromOtherMaterialID(const LLMaterialID& pOtherMaterialID);
@@ -75,5 +83,23 @@ private:
 	U8 mID[MATERIAL_ID_SIZE];
 } ;
 
+// std::hash implementation for LLMaterialID
+namespace std
+{
+	template<> struct hash<LLMaterialID>
+	{
+		inline size_t operator()(const LLMaterialID& id) const noexcept
+		{
+			return (size_t)id.getDigest64();
+		}
+	};
+}
+
+// For use with boost containers.
+inline size_t hash_value(const LLMaterialID& id) noexcept
+{
+	return (size_t)id.getDigest64();
+}
+
 #endif // LL_LLMATERIALID_H