From 59b61a1f64c2d77655cef89575cfd172c1e36832 Mon Sep 17 00:00:00 2001 From: "K. S. Ernest (iFire) Lee" Date: Sat, 9 Jan 2021 10:04:09 -0800 Subject: Scale error in mesh optimizer so it uses absolute scale. Switch to simplify sloppy for another try. Update to meshoptimizer e3f53f66e7a35b9b8764bee478589d79e34fa698. --- thirdparty/meshoptimizer/indexcodec.cpp | 2 +- thirdparty/meshoptimizer/meshoptimizer.h | 20 +++++++++-------- thirdparty/meshoptimizer/simplifier.cpp | 38 ++++++++++++++++++++++---------- 3 files changed, 38 insertions(+), 22 deletions(-) (limited to 'thirdparty/meshoptimizer') diff --git a/thirdparty/meshoptimizer/indexcodec.cpp b/thirdparty/meshoptimizer/indexcodec.cpp index 5c35eb43ae..e4495b8586 100644 --- a/thirdparty/meshoptimizer/indexcodec.cpp +++ b/thirdparty/meshoptimizer/indexcodec.cpp @@ -108,7 +108,7 @@ static unsigned int decodeVByte(const unsigned char*& data) for (int i = 0; i < 4; ++i) { unsigned char group = *data++; - result |= (group & 127) << shift; + result |= unsigned(group & 127) << shift; shift += 7; if (group < 128) diff --git a/thirdparty/meshoptimizer/meshoptimizer.h b/thirdparty/meshoptimizer/meshoptimizer.h index 4071f0a371..1714000384 100644 --- a/thirdparty/meshoptimizer/meshoptimizer.h +++ b/thirdparty/meshoptimizer/meshoptimizer.h @@ -262,7 +262,7 @@ MESHOPTIMIZER_EXPERIMENTAL void meshopt_decodeFilterExp(void* buffer, size_t ver * The resulting index buffer references vertices from the original vertex buffer. * If the original vertex data isn't required, creating a compact vertex buffer using meshopt_optimizeVertexFetch is recommended. * - * destination must contain enough space for the *source* index buffer (since optimization is iterative, this means index_count elements - *not* target_index_count!) + * destination must contain enough space for the target index buffer, worst case is index_count elements (*not* target_index_count)! * vertex_positions should have float3 position in the first 12 bytes of each vertex - similar to glVertexPointer * target_error represents the error relative to mesh extents that can be tolerated, e.g. 0.01 = 1% deformation * result_error can be NULL; when it's not NULL, it will contain the resulting (relative) error after simplification @@ -272,15 +272,17 @@ MESHOPTIMIZER_EXPERIMENTAL size_t meshopt_simplify(unsigned int* destination, co /** * Experimental: Mesh simplifier (sloppy) * Reduces the number of triangles in the mesh, sacrificing mesh apperance for simplification performance - * The algorithm doesn't preserve mesh topology but is always able to reach target triangle count. + * The algorithm doesn't preserve mesh topology but can stop short of the target goal based on target error. * Returns the number of indices after simplification, with destination containing new index data * The resulting index buffer references vertices from the original vertex buffer. * If the original vertex data isn't required, creating a compact vertex buffer using meshopt_optimizeVertexFetch is recommended. * - * destination must contain enough space for the target index buffer + * destination must contain enough space for the target index buffer, worst case is index_count elements (*not* target_index_count)! * vertex_positions should have float3 position in the first 12 bytes of each vertex - similar to glVertexPointer + * target_error represents the error relative to mesh extents that can be tolerated, e.g. 0.01 = 1% deformation + * result_error can be NULL; when it's not NULL, it will contain the resulting (relative) error after simplification */ -MESHOPTIMIZER_EXPERIMENTAL size_t meshopt_simplifySloppy(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); +MESHOPTIMIZER_EXPERIMENTAL size_t meshopt_simplifySloppy(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, float* result_error); /** * Experimental: Point cloud simplifier @@ -289,7 +291,7 @@ MESHOPTIMIZER_EXPERIMENTAL size_t meshopt_simplifySloppy(unsigned int* destinati * The resulting index buffer references vertices from the original vertex buffer. * If the original vertex data isn't required, creating a compact vertex buffer using meshopt_optimizeVertexFetch is recommended. * - * destination must contain enough space for the target index buffer + * destination must contain enough space for the target index buffer (target_vertex_count elements) * vertex_positions should have float3 position in the first 12 bytes of each vertex - similar to glVertexPointer */ MESHOPTIMIZER_EXPERIMENTAL size_t meshopt_simplifyPoints(unsigned int* destination, const float* vertex_positions, size_t vertex_count, size_t vertex_positions_stride, size_t target_vertex_count); @@ -533,7 +535,7 @@ inline int meshopt_decodeIndexSequence(T* destination, size_t index_count, const template inline size_t meshopt_simplify(T* destination, const T* 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, float* result_error = 0); template -inline size_t meshopt_simplifySloppy(T* destination, const T* indices, size_t index_count, const float* vertex_positions, size_t vertex_count, size_t vertex_positions_stride, size_t target_index_count); +inline size_t meshopt_simplifySloppy(T* destination, const T* 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, float* result_error = 0); template inline size_t meshopt_stripify(T* destination, const T* indices, size_t index_count, size_t vertex_count, T restart_index); template @@ -855,12 +857,12 @@ inline size_t meshopt_simplify(T* destination, const T* indices, size_t index_co } template -inline size_t meshopt_simplifySloppy(T* destination, const T* indices, size_t index_count, const float* vertex_positions, size_t vertex_count, size_t vertex_positions_stride, size_t target_index_count) +inline size_t meshopt_simplifySloppy(T* destination, const T* 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, float* result_error) { meshopt_IndexAdapter in(0, indices, index_count); - meshopt_IndexAdapter out(destination, 0, target_index_count); + meshopt_IndexAdapter out(destination, 0, index_count); - return meshopt_simplifySloppy(out.data, in.data, index_count, vertex_positions, vertex_count, vertex_positions_stride, target_index_count); + return meshopt_simplifySloppy(out.data, in.data, index_count, vertex_positions, vertex_count, vertex_positions_stride, target_index_count, target_error, result_error); } template diff --git a/thirdparty/meshoptimizer/simplifier.cpp b/thirdparty/meshoptimizer/simplifier.cpp index 5205b01172..942db14461 100644 --- a/thirdparty/meshoptimizer/simplifier.cpp +++ b/thirdparty/meshoptimizer/simplifier.cpp @@ -1400,7 +1400,7 @@ size_t meshopt_simplify(unsigned int* destination, const unsigned int* indices, return result_count; } -size_t meshopt_simplifySloppy(unsigned int* destination, const unsigned int* indices, size_t index_count, const float* vertex_positions_data, size_t vertex_count, size_t vertex_positions_stride, size_t target_index_count) +size_t meshopt_simplifySloppy(unsigned int* destination, const unsigned int* indices, size_t index_count, const float* vertex_positions_data, size_t vertex_count, size_t vertex_positions_stride, size_t target_index_count, float target_error, float* out_result_error) { using namespace meshopt; @@ -1412,9 +1412,6 @@ size_t meshopt_simplifySloppy(unsigned int* destination, const unsigned int* ind // we expect to get ~2 triangles/vertex in the output size_t target_cell_count = target_index_count / 6; - if (target_cell_count == 0) - return 0; - meshopt_Allocator allocator; Vector3* vertex_positions = allocator.allocate(vertex_count); @@ -1431,18 +1428,25 @@ size_t meshopt_simplifySloppy(unsigned int* destination, const unsigned int* ind const int kInterpolationPasses = 5; // invariant: # of triangles in min_grid <= target_count - int min_grid = 0; + int min_grid = int(1.f / (target_error < 1e-3f ? 1e-3f : target_error)); int max_grid = 1025; size_t min_triangles = 0; size_t max_triangles = index_count / 3; + // when we're error-limited, we compute the triangle count for the min. size; this accelerates convergence and provides the correct answer when we can't use a larger grid + if (min_grid > 1) + { + computeVertexIds(vertex_ids, vertex_positions, vertex_count, min_grid); + min_triangles = countTriangles(vertex_ids, indices, index_count); + } + // instead of starting in the middle, let's guess as to what the answer might be! triangle count usually grows as a square of grid size... int next_grid_size = int(sqrtf(float(target_cell_count)) + 0.5f); for (int pass = 0; pass < 10 + kInterpolationPasses; ++pass) { - assert(min_triangles < target_index_count / 3); - assert(max_grid - min_grid > 1); + if (min_triangles >= target_index_count / 3 || max_grid - min_grid <= 1) + break; // we clamp the prediction of the grid size to make sure that the search converges int grid_size = next_grid_size; @@ -1471,16 +1475,18 @@ size_t meshopt_simplifySloppy(unsigned int* destination, const unsigned int* ind max_triangles = triangles; } - if (triangles == target_index_count / 3 || max_grid - min_grid <= 1) - break; - // we start by using interpolation search - it usually converges faster // however, interpolation search has a worst case of O(N) so we switch to binary search after a few iterations which converges in O(logN) next_grid_size = (pass < kInterpolationPasses) ? int(tip + 0.5f) : (min_grid + max_grid) / 2; } if (min_triangles == 0) + { + if (out_result_error) + *out_result_error = 1.f; + return 0; + } // build vertex->cell association by mapping all vertices with the same quantized position to the same cell size_t table_size = hashBuckets2(vertex_count); @@ -1503,18 +1509,26 @@ size_t meshopt_simplifySloppy(unsigned int* destination, const unsigned int* ind fillCellRemap(cell_remap, cell_errors, cell_count, vertex_cells, cell_quadrics, vertex_positions, vertex_count); + // compute error + float result_error = 0.f; + + for (size_t i = 0; i < cell_count; ++i) + result_error = result_error < cell_errors[i] ? cell_errors[i] : result_error; + // collapse triangles! // note that we need to filter out triangles that we've already output because we very frequently generate redundant triangles between cells :( size_t tritable_size = hashBuckets2(min_triangles); unsigned int* tritable = allocator.allocate(tritable_size); size_t write = filterTriangles(destination, tritable, tritable_size, indices, index_count, vertex_cells, cell_remap); - assert(write <= target_index_count); #if TRACE - printf("result: %d cells, %d triangles (%d unfiltered)\n", int(cell_count), int(write / 3), int(min_triangles)); + printf("result: %d cells, %d triangles (%d unfiltered), error %e\n", int(cell_count), int(write / 3), int(min_triangles), sqrtf(result_error)); #endif + if (out_result_error) + *out_result_error = sqrtf(result_error); + return write; } -- cgit v1.2.3