Rework Mesh handling on scene importing.

-Reworked how meshes are treated by importer by using EditorSceneImporterMesh and EditorSceneImporterMeshNode. Instead of Mesh and MeshInstance, this allows more efficient processing of meshes before they are actually registered in the RenderingServer.
-Integrated MeshOptimizer
-Reworked internals of SurfaceTool to use arrays, making it more performant and easy to run optimizatons on.

1 files changed, 19 insertions, 9 deletions

diff --git a/scene/resources/surface_tool.h b/scene/resources/surface_tool.h
index 4a5c7d990c..e80a5339a9 100644
--- a/scene/resources/surface_tool.h
+++ b/scene/resources/surface_tool.h
@@ -31,8 +31,8 @@
 #ifndef SURFACE_TOOL_H
 #define SURFACE_TOOL_H
 
+#include "core/templates/local_vector.h"
 #include "scene/resources/mesh.h"
-
 #include "thirdparty/misc/mikktspace.h"
 
 class SurfaceTool : public Reference {
@@ -50,6 +50,7 @@ public:
 		Vector<int> bones;
 		Vector<float> weights;
 		Color custom[RS::ARRAY_CUSTOM_COUNT];
+		uint32_t smooth_group = 0;
 
 		bool operator==(const Vertex &p_vertex) const;
 
@@ -73,6 +74,11 @@ public:
 		SKIN_8_WEIGHTS
 	};
 
+	typedef void (*OptimizeVertexCacheFunc)(unsigned int *destination, const unsigned int *indices, size_t index_count, size_t vertex_count);
+	static OptimizeVertexCacheFunc optimize_vertex_cache_func;
+	typedef size_t (*SimplifyFunc)(unsigned int *destination, const unsigned int *indices, size_t index_count, const float *vertex_positions, size_t vertex_count, size_t vertex_positions_stride, size_t target_index_count, float target_error);
+	static SimplifyFunc simplify_func;
+
 private:
 	struct VertexHasher {
 		static _FORCE_INLINE_ uint32_t hash(const Vertex &p_vtx);
@@ -92,9 +98,8 @@ private:
 	uint32_t format;
 	Ref<Material> material;
 	//arrays
-	List<Vertex> vertex_array;
-	List<int> index_array;
-	Map<int, bool> smooth_groups;
+	LocalVector<Vertex> vertex_array;
+	LocalVector<int> index_array;
 
 	//memory
 	Color last_color;
@@ -104,6 +109,7 @@ private:
 	Vector<int> last_bones;
 	Vector<float> last_weights;
 	Plane last_tangent;
+	uint32_t last_smooth_group = 0;
 
 	SkinWeightCount skin_weights;
 
@@ -111,8 +117,8 @@ private:
 
 	CustomFormat last_custom_format[RS::ARRAY_CUSTOM_COUNT];
 
-	void _create_list_from_arrays(Array arr, List<Vertex> *r_vertex, List<int> *r_index, uint32_t &lformat);
-	void _create_list(const Ref<Mesh> &p_existing, int p_surface, List<Vertex> *r_vertex, List<int> *r_index, uint32_t &lformat);
+	void _create_list_from_arrays(Array arr, LocalVector<Vertex> *r_vertex, LocalVector<int> *r_index, uint32_t &lformat);
+	void _create_list(const Ref<Mesh> &p_existing, int p_surface, LocalVector<Vertex> *r_vertex, LocalVector<int> *r_index, uint32_t &lformat);
 
 	//mikktspace callbacks
 	static int mikktGetNumFaces(const SMikkTSpaceContext *pContext);
@@ -143,10 +149,10 @@ public:
 	void set_custom(int p_index, const Color &p_custom);
 	void set_bones(const Vector<int> &p_bones);
 	void set_weights(const Vector<float> &p_weights);
+	void set_smooth_group(uint32_t p_group);
 
 	void add_vertex(const Vector3 &p_vertex);
 
-	void add_smooth_group(bool p_smooth);
 	void add_triangle_fan(const Vector<Vector3> &p_vertices, const Vector<Vector2> &p_uvs = Vector<Vector2>(), const Vector<Color> &p_colors = Vector<Color>(), const Vector<Vector2> &p_uv2s = Vector<Vector2>(), const Vector<Vector3> &p_normals = Vector<Vector3>(), const Vector<Plane> &p_tangents = Vector<Plane>());
 
 	void add_index(int p_index);
@@ -156,14 +162,18 @@ public:
 	void generate_normals(bool p_flip = false);
 	void generate_tangents();
 
+	void optimize_indices_for_cache();
+	float get_max_axis_length() const;
+	Vector<int> generate_lod(float p_threshold, int p_target_index_count = 3);
+
 	void set_material(const Ref<Material> &p_material);
 
 	void clear();
 
-	List<Vertex> &get_vertex_array() { return vertex_array; }
+	LocalVector<Vertex> &get_vertex_array() { return vertex_array; }
 
 	void create_from_triangle_arrays(const Array &p_arrays);
-	static Vector<Vertex> create_vertex_array_from_triangle_arrays(const Array &p_arrays, uint32_t *r_format = nullptr);
+	static void create_vertex_array_from_triangle_arrays(const Array &p_arrays, LocalVector<Vertex> &ret, uint32_t *r_format = nullptr);
 	Array commit_to_arrays();
 	void create_from(const Ref<Mesh> &p_existing, int p_surface);
 	void create_from_blend_shape(const Ref<Mesh> &p_existing, int p_surface, const String &p_blend_shape_name);