Merge pull request #790 from zeux/gltf-ddperf

gltfpack: Accelerate deduplication pass for scenes with a lot of primitives

gltf/gltfpack.cpp

@@ -2,7 +2,7 @@
 #include "gltfpack.h"
 
 #include <algorithm>
-#include <map>
+#include <unordered_map>
 
 #include <locale.h>
 #include <stdint.h>
@@ -329,6 +329,18 @@ static bool isExtensionSupported(const ExtensionInfo* extensions, size_t count,
 	return false;
 }
 
+namespace std
+{
+template <>
+struct hash<std::pair<uint64_t, uint64_t> >
+{
+	size_t operator()(const std::pair<uint64_t, uint64_t>& x) const
+	{
+		return std::hash<uint64_t>()(x.first ^ x.second);
+	}
+};
+} // namespace std
+
 static void process(cgltf_data* data, const char* input_path, const char* output_path, const char* report_path, std::vector<Mesh>& meshes, std::vector<Animation>& animations, const Settings& settings, std::string& json, std::string& bin, std::string& fallback, size_t& fallback_size)
 {
 	if (settings.verbose)
@@ -565,7 +577,7 @@ static void process(cgltf_data* data, const char* input_path, const char* output
 		ext_texture_transform = ext_texture_transform || mi.uses_texture_transform;
 	}
 
-	std::map<std::pair<uint64_t, uint64_t>, std::pair<size_t, size_t> > primitive_cache;
+	std::unordered_map<std::pair<uint64_t, uint64_t>, std::pair<size_t, size_t> > primitive_cache;
 
 	for (size_t i = 0; i < meshes.size(); ++i)
 	{

gltf/mesh.cpp

@@ -2,6 +2,7 @@
 #include "gltfpack.h"
 
 #include <algorithm>
+#include <unordered_map>
 
 #include <math.h>
 #include <stdint.h>
@@ -355,8 +356,15 @@ static bool canDedupMesh(const Mesh& mesh)
 
 void dedupMeshes(std::vector<Mesh>& meshes)
 {
+	std::unordered_map<uint64_t, int> hashes;
+
 	for (size_t i = 0; i < meshes.size(); ++i)
-		hashMesh(meshes[i]);
+	{
+		Mesh& mesh = meshes[i];
+
+		hashMesh(mesh);
+		hashes[mesh.geometry_hash[0] ^ mesh.geometry_hash[1]]++;
+	}
 
 	for (size_t i = 0; i < meshes.size(); ++i)
 	{
@@ -365,6 +373,9 @@ void dedupMeshes(std::vector<Mesh>& meshes)
 		if (!canDedupMesh(target))
 			continue;
 
+		if (hashes[target.geometry_hash[0] ^ target.geometry_hash[1]] <= 1)
+			continue;
+
 		for (size_t j = i + 1; j < meshes.size(); ++j)
 		{
 			Mesh& mesh = meshes[j];
@@ -397,6 +408,16 @@ void dedupMeshes(std::vector<Mesh>& meshes)
 			mesh.instances.clear();
 		}
 	}
+
+	for (size_t i = 0; i < meshes.size(); ++i)
+	{
+		Mesh& target = meshes[i];
+		if (target.nodes.size() <= 1)
+			continue;
+
+		std::sort(target.nodes.begin(), target.nodes.end());
+		target.nodes.erase(std::unique(target.nodes.begin(), target.nodes.end()), target.nodes.end());
+	}
 }
 
 void mergeMeshInstances(Mesh& mesh)
@@ -759,7 +780,7 @@ static void simplifyMesh(Mesh& mesh, float threshold, float error, bool attribut
 
 	size_t vertex_count = mesh.streams[0].data.size();
 
-	size_t target_index_count = size_t(double(mesh.indices.size() / 3) * threshold) * 3;
+	size_t target_index_count = size_t(double(size_t(mesh.indices.size() / 3)) * threshold) * 3;
 	float target_error = error;
 	float target_error_aggressive = 1e-1f;