// This file is part of meshoptimizer library; see meshoptimizer.h for version/license details #include "meshoptimizer.h" #include <assert.h> #include <string.h> size_t meshopt_optimizeVertexFetchRemap(unsigned int* destination, const unsigned int* indices, size_t index_count, size_t vertex_count) { assert(index_count % 3 == 0); memset(destination, -1, vertex_count * sizeof(unsigned int)); unsigned int next_vertex = 0; for (size_t i = 0; i < index_count; ++i) { unsigned int index = indices[i]; assert(index < vertex_count); if (destination[index] == ~0u) { destination[index] = next_vertex++; } } assert(next_vertex <= vertex_count); return next_vertex; } size_t meshopt_optimizeVertexFetch(void* destination, unsigned int* indices, size_t index_count, const void* vertices, size_t vertex_count, size_t vertex_size) { assert(index_count % 3 == 0); assert(vertex_size > 0 && vertex_size <= 256); meshopt_Allocator allocator; // support in-place optimization if (destination == vertices) { unsigned char* vertices_copy = allocator.allocate<unsigned char>(vertex_count * vertex_size); memcpy(vertices_copy, vertices, vertex_count * vertex_size); vertices = vertices_copy; } // build vertex remap table unsigned int* vertex_remap = allocator.allocate<unsigned int>(vertex_count); memset(vertex_remap, -1, vertex_count * sizeof(unsigned int)); unsigned int next_vertex = 0; for (size_t i = 0; i < index_count; ++i) { unsigned int index = indices[i]; assert(index < vertex_count); unsigned int& remap = vertex_remap[index]; if (remap == ~0u) // vertex was not added to destination VB { // add vertex memcpy(static_cast<unsigned char*>(destination) + next_vertex * vertex_size, static_cast<const unsigned char*>(vertices) + index * vertex_size, vertex_size); remap = next_vertex++; } // modify indices in place indices[i] = remap; } assert(next_vertex <= vertex_count); return next_vertex; }