From fc8ea1d828a6b00c3c0ac0ed31c45fdad61a0c9c Mon Sep 17 00:00:00 2001 From: "K. S. Ernest (iFire) Lee" Date: Fri, 9 Apr 2021 22:44:36 -0700 Subject: Update with experimental mesh optimizer. Normals being optimized has better quality now. Test simplify once and then use a slightly less tolerant error for the target error. --- editor/import/scene_importer_mesh.cpp | 105 +++++---- editor/import/scene_importer_mesh.h | 1 + modules/meshoptimizer/register_types.cpp | 1 + scene/resources/surface_tool.cpp | 1 + scene/resources/surface_tool.h | 2 + thirdparty/README.md | 3 + thirdparty/meshoptimizer/meshoptimizer.h | 5 + .../patches/attribute-aware-simplify.patch | 262 +++++++++++++++++++++ thirdparty/meshoptimizer/simplifier.cpp | 152 +++++++++++- 9 files changed, 485 insertions(+), 47 deletions(-) create mode 100644 thirdparty/meshoptimizer/patches/attribute-aware-simplify.patch diff --git a/editor/import/scene_importer_mesh.cpp b/editor/import/scene_importer_mesh.cpp index bc7e8a1626..fa1a027a8d 100644 --- a/editor/import/scene_importer_mesh.cpp +++ b/editor/import/scene_importer_mesh.cpp @@ -30,6 +30,7 @@ #include "scene_importer_mesh.h" +#include "core/math/math_defs.h" #include "scene/resources/surface_tool.h" void EditorSceneImporterMesh::add_blend_shape(const String &p_name) { @@ -141,6 +142,18 @@ void EditorSceneImporterMesh::set_surface_material(int p_surface, const Ref normals = surfaces[i].arrays[RS::ARRAY_NORMAL]; uint32_t vertex_count = vertices.size(); const Vector3 *vertices_ptr = vertices.ptr(); - - int min_indices = 10; - int index_target = indices.size() / 2; - print_line("Total indices: " + itos(indices.size())); - float mesh_scale = SurfaceTool::simplify_scale_func((const float *)vertices_ptr, vertex_count, sizeof(Vector3)); - const float target_error = 1e-3f; - float abs_target_error = target_error / mesh_scale; + Vector attributes; + Vector normal_weights; + int32_t attribute_count = 6; + if (normals.size()) { + attributes.resize(normals.size() * attribute_count); + for (int32_t normal_i = 0; normal_i < normals.size(); normal_i++) { + Basis basis; + basis.set_euler(normals[normal_i]); + Vector3 basis_x = basis.get_axis(0); + Vector3 basis_y = basis.get_axis(1); + basis = compute_rotation_matrix_from_ortho_6d(basis_x, basis_y); + basis_x = basis.get_axis(0); + basis_y = basis.get_axis(1); + attributes.write[normal_i * attribute_count + 0] = basis_x.x; + attributes.write[normal_i * attribute_count + 1] = basis_x.y; + attributes.write[normal_i * attribute_count + 2] = basis_x.z; + attributes.write[normal_i * attribute_count + 3] = basis_y.x; + attributes.write[normal_i * attribute_count + 4] = basis_y.y; + attributes.write[normal_i * attribute_count + 5] = basis_y.z; + } + normal_weights.resize(vertex_count); + for (int32_t weight_i = 0; weight_i < normal_weights.size(); weight_i++) { + normal_weights.write[weight_i] = 1.0; + } + } else { + attribute_count = 0; + } + const int min_indices = 10; + const float error_tolerance = 1.44224'95703; // Cube root of 3 + const float threshold = 1.0 / error_tolerance; + int index_target = indices.size() * threshold; + float max_mesh_error_percentage = 1e0f; + float mesh_error = 0.0f; while (index_target > min_indices) { - float error; Vector new_indices; new_indices.resize(indices.size()); - size_t new_len = SurfaceTool::simplify_func((unsigned int *)new_indices.ptrw(), (const unsigned int *)indices.ptr(), indices.size(), (const float *)vertices_ptr, vertex_count, sizeof(Vector3), index_target, abs_target_error, &error); - if ((int)new_len > (index_target * 120 / 100)) { - // Attribute discontinuities break normals. - bool is_sloppy = false; - if (is_sloppy) { - abs_target_error = target_error / mesh_scale; - index_target = new_len; - while (index_target > min_indices) { - Vector sloppy_new_indices; - sloppy_new_indices.resize(indices.size()); - new_len = SurfaceTool::simplify_sloppy_func((unsigned int *)sloppy_new_indices.ptrw(), (const unsigned int *)indices.ptr(), indices.size(), (const float *)vertices_ptr, vertex_count, sizeof(Vector3), index_target, abs_target_error, &error); - if ((int)new_len > (index_target * 120 / 100)) { - break; // 20 percent tolerance - } - sloppy_new_indices.resize(new_len); - Surface::LOD lod; - lod.distance = error * mesh_scale; - abs_target_error = lod.distance; - if (Math::is_equal_approx(abs_target_error, 0.0f)) { - return; - } - lod.indices = sloppy_new_indices; - print_line("Lod " + itos(surfaces.write[i].lods.size()) + " shoot for " + itos(index_target / 3) + " triangles, got " + itos(new_len / 3) + " triangles. Distance " + rtos(lod.distance) + ". Use simplify sloppy."); - surfaces.write[i].lods.push_back(lod); - index_target /= 2; - } - } - break; // 20 percent tolerance + size_t new_len = SurfaceTool::simplify_with_attrib_func((unsigned int *)new_indices.ptrw(), (const unsigned int *)indices.ptr(), indices.size(), (const float *)vertices_ptr, vertex_count, sizeof(Vector3), index_target, max_mesh_error_percentage, &mesh_error, (float *)attributes.ptrw(), normal_weights.ptrw(), attribute_count); + if ((int)new_len > (index_target * error_tolerance)) { + break; } - new_indices.resize(new_len); Surface::LOD lod; - lod.distance = error * mesh_scale; - abs_target_error = lod.distance; - if (Math::is_equal_approx(abs_target_error, 0.0f)) { - return; + lod.distance = mesh_error; + if (Math::is_equal_approx(mesh_error, 0.0f)) { + break; + } + if (new_len <= 0) { + break; } + new_indices.resize(new_len); lod.indices = new_indices; - print_line("Lod " + itos(surfaces.write[i].lods.size()) + " shoot for " + itos(index_target / 3) + " triangles, got " + itos(new_len / 3) + " triangles. Distance " + rtos(lod.distance)); + print_line("Lod " + itos(surfaces.write[i].lods.size()) + " begin with " + itos(indices.size() / 3) + " triangles and shoot for " + itos(index_target / 3) + " triangles. Got " + itos(new_len / 3) + " triangles. Lod screen ratio " + rtos(lod.distance)); surfaces.write[i].lods.push_back(lod); - index_target /= 2; + index_target *= threshold; } } } diff --git a/editor/import/scene_importer_mesh.h b/editor/import/scene_importer_mesh.h index b3e8137e0a..c00339a620 100644 --- a/editor/import/scene_importer_mesh.h +++ b/editor/import/scene_importer_mesh.h @@ -67,6 +67,7 @@ class EditorSceneImporterMesh : public Resource { Ref shadow_mesh; Size2i lightmap_size_hint; + Basis compute_rotation_matrix_from_ortho_6d(Vector3 p_x_raw, Vector3 y_raw); protected: void _set_data(const Dictionary &p_data); diff --git a/modules/meshoptimizer/register_types.cpp b/modules/meshoptimizer/register_types.cpp index a03310f518..77cc82a4e2 100644 --- a/modules/meshoptimizer/register_types.cpp +++ b/modules/meshoptimizer/register_types.cpp @@ -35,6 +35,7 @@ void register_meshoptimizer_types() { SurfaceTool::optimize_vertex_cache_func = meshopt_optimizeVertexCache; SurfaceTool::simplify_func = meshopt_simplify; + SurfaceTool::simplify_with_attrib_func = meshopt_simplifyWithAttributes; SurfaceTool::simplify_scale_func = meshopt_simplifyScale; SurfaceTool::simplify_sloppy_func = meshopt_simplifySloppy; } diff --git a/scene/resources/surface_tool.cpp b/scene/resources/surface_tool.cpp index ff682a40f4..f2143e683d 100644 --- a/scene/resources/surface_tool.cpp +++ b/scene/resources/surface_tool.cpp @@ -35,6 +35,7 @@ SurfaceTool::OptimizeVertexCacheFunc SurfaceTool::optimize_vertex_cache_func = nullptr; SurfaceTool::SimplifyFunc SurfaceTool::simplify_func = nullptr; +SurfaceTool::SimplifyWithAttribFunc SurfaceTool::simplify_with_attrib_func = nullptr; SurfaceTool::SimplifyScaleFunc SurfaceTool::simplify_scale_func = nullptr; SurfaceTool::SimplifySloppyFunc SurfaceTool::simplify_sloppy_func = nullptr; diff --git a/scene/resources/surface_tool.h b/scene/resources/surface_tool.h index 28addf2245..f5f3a95b14 100644 --- a/scene/resources/surface_tool.h +++ b/scene/resources/surface_tool.h @@ -78,6 +78,8 @@ public: 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, float *r_error); static SimplifyFunc simplify_func; + typedef size_t (*SimplifyWithAttribFunc)(unsigned int *destination, const unsigned int *indices, size_t index_count, const float *vertex_data, size_t vertex_count, size_t vertex_stride, size_t target_index_count, float target_error, float *result_error, const float *attributes, const float *attribute_weights, size_t attribute_count); + static SimplifyWithAttribFunc simplify_with_attrib_func; typedef float (*SimplifyScaleFunc)(const float *vertex_positions, size_t vertex_count, size_t vertex_positions_stride); static SimplifyScaleFunc simplify_scale_func; typedef size_t (*SimplifySloppyFunc)(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); diff --git a/thirdparty/README.md b/thirdparty/README.md index 7cedd1a2cb..d3599fd195 100644 --- a/thirdparty/README.md +++ b/thirdparty/README.md @@ -375,6 +375,9 @@ Files extracted from upstream repository: - All files in `src/`. - `LICENSE.md`. +An [experimental upstream feature](https://github.com/zeux/meshoptimizer/tree/simplify-attr), +has been backported, see patch in `patches` directory. + ## miniupnpc diff --git a/thirdparty/meshoptimizer/meshoptimizer.h b/thirdparty/meshoptimizer/meshoptimizer.h index fe8d349731..e44b99ce52 100644 --- a/thirdparty/meshoptimizer/meshoptimizer.h +++ b/thirdparty/meshoptimizer/meshoptimizer.h @@ -298,6 +298,11 @@ MESHOPTIMIZER_EXPERIMENTAL void meshopt_decodeFilterExp(void* buffer, size_t ver */ MESHOPTIMIZER_EXPERIMENTAL size_t meshopt_simplify(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: Mesh simplifier with attribute metric; attributes follow xyz position data atm (vertex data must contain 3 + attribute_count floats per vertex) + */ +MESHOPTIMIZER_EXPERIMENTAL size_t meshopt_simplifyWithAttributes(unsigned int* destination, const unsigned int* indices, size_t index_count, const float* vertex_data, size_t vertex_count, size_t vertex_stride, size_t target_index_count, float target_error, float* result_error, const float* attributes, const float* attribute_weights, size_t attribute_count); + /** * Experimental: Mesh simplifier (sloppy) * Reduces the number of triangles in the mesh, sacrificing mesh apperance for simplification performance diff --git a/thirdparty/meshoptimizer/patches/attribute-aware-simplify.patch b/thirdparty/meshoptimizer/patches/attribute-aware-simplify.patch new file mode 100644 index 0000000000..cf648b0da3 --- /dev/null +++ b/thirdparty/meshoptimizer/patches/attribute-aware-simplify.patch @@ -0,0 +1,262 @@ +diff --git a/thirdparty/meshoptimizer/meshoptimizer.h b/thirdparty/meshoptimizer/meshoptimizer.h +index fe8d349731..e44b99ce52 100644 +--- a/thirdparty/meshoptimizer/meshoptimizer.h ++++ b/thirdparty/meshoptimizer/meshoptimizer.h +@@ -298,6 +298,11 @@ MESHOPTIMIZER_EXPERIMENTAL void meshopt_decodeFilterExp(void* buffer, size_t ver + */ + MESHOPTIMIZER_EXPERIMENTAL size_t meshopt_simplify(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: Mesh simplifier with attribute metric; attributes follow xyz position data atm (vertex data must contain 3 + attribute_count floats per vertex) ++ */ ++MESHOPTIMIZER_EXPERIMENTAL size_t meshopt_simplifyWithAttributes(unsigned int* destination, const unsigned int* indices, size_t index_count, const float* vertex_data, size_t vertex_count, size_t vertex_stride, size_t target_index_count, float target_error, float* result_error, const float* attributes, const float* attribute_weights, size_t attribute_count); ++ + /** + * Experimental: Mesh simplifier (sloppy) + * Reduces the number of triangles in the mesh, sacrificing mesh apperance for simplification performance +diff --git a/thirdparty/meshoptimizer/simplifier.cpp b/thirdparty/meshoptimizer/simplifier.cpp +index b2cb589462..059cabb055 100644 +--- a/thirdparty/meshoptimizer/simplifier.cpp ++++ b/thirdparty/meshoptimizer/simplifier.cpp +@@ -20,6 +20,8 @@ + #define TRACESTATS(i) (void)0 + #endif + ++#define ATTRIBUTES 8 ++ + // This work is based on: + // Michael Garland and Paul S. Heckbert. Surface simplification using quadric error metrics. 1997 + // Michael Garland. Quadric-based polygonal surface simplification. 1999 +@@ -358,6 +360,10 @@ static void classifyVertices(unsigned char* result, unsigned int* loop, unsigned + struct Vector3 + { + float x, y, z; ++ ++#if ATTRIBUTES ++ float a[ATTRIBUTES]; ++#endif + }; + + static float rescalePositions(Vector3* result, const float* vertex_positions_data, size_t vertex_count, size_t vertex_positions_stride) +@@ -414,6 +420,13 @@ struct Quadric + float a10, a20, a21; + float b0, b1, b2, c; + float w; ++ ++#if ATTRIBUTES ++ float gx[ATTRIBUTES]; ++ float gy[ATTRIBUTES]; ++ float gz[ATTRIBUTES]; ++ float gw[ATTRIBUTES]; ++#endif + }; + + struct Collapse +@@ -456,6 +469,16 @@ static void quadricAdd(Quadric& Q, const Quadric& R) + Q.b2 += R.b2; + Q.c += R.c; + Q.w += R.w; ++ ++#if ATTRIBUTES ++ for (int k = 0; k < ATTRIBUTES; ++k) ++ { ++ Q.gx[k] += R.gx[k]; ++ Q.gy[k] += R.gy[k]; ++ Q.gz[k] += R.gz[k]; ++ Q.gw[k] += R.gw[k]; ++ } ++#endif + } + + static float quadricError(const Quadric& Q, const Vector3& v) +@@ -481,6 +504,17 @@ static float quadricError(const Quadric& Q, const Vector3& v) + r += ry * v.y; + r += rz * v.z; + ++#if ATTRIBUTES ++ // see quadricUpdateAttributes for general derivation; here we need to add the parts of (eval(pos) - attr)^2 that depend on attr ++ for (int k = 0; k < ATTRIBUTES; ++k) ++ { ++ float a = v.a[k]; ++ ++ r += a * a * Q.w; ++ r -= 2 * a * (v.x * Q.gx[k] + v.y * Q.gy[k] + v.z * Q.gz[k] + Q.gw[k]); ++ } ++#endif ++ + float s = Q.w == 0.f ? 0.f : 1.f / Q.w; + + return fabsf(r) * s; +@@ -504,6 +538,13 @@ static void quadricFromPlane(Quadric& Q, float a, float b, float c, float d, flo + Q.b2 = c * dw; + Q.c = d * dw; + Q.w = w; ++ ++#if ATTRIBUTES ++ memset(Q.gx, 0, sizeof(Q.gx)); ++ memset(Q.gy, 0, sizeof(Q.gy)); ++ memset(Q.gz, 0, sizeof(Q.gz)); ++ memset(Q.gw, 0, sizeof(Q.gw)); ++#endif + } + + static void quadricFromPoint(Quadric& Q, float x, float y, float z, float w) +@@ -556,6 +597,84 @@ static void quadricFromTriangleEdge(Quadric& Q, const Vector3& p0, const Vector3 + quadricFromPlane(Q, normal.x, normal.y, normal.z, -distance, length * weight); + } + ++#if ATTRIBUTES ++static void quadricUpdateAttributes(Quadric& Q, const Vector3& p0, const Vector3& p1, const Vector3& p2, float w) ++{ ++ // for each attribute we want to encode the following function into the quadric: ++ // (eval(pos) - attr)^2 ++ // where eval(pos) interpolates attribute across the triangle like so: ++ // eval(pos) = pos.x * gx + pos.y * gy + pos.z * gz + gw ++ // where gx/gy/gz/gw are gradients ++ Vector3 p10 = {p1.x - p0.x, p1.y - p0.y, p1.z - p0.z}; ++ Vector3 p20 = {p2.x - p0.x, p2.y - p0.y, p2.z - p0.z}; ++ ++ // we compute gradients using barycentric coordinates; barycentric coordinates can be computed as follows: ++ // v = (d11 * d20 - d01 * d21) / denom ++ // w = (d00 * d21 - d01 * d20) / denom ++ // u = 1 - v - w ++ // here v0, v1 are triangle edge vectors, v2 is a vector from point to triangle corner, and dij = dot(vi, vj) ++ const Vector3& v0 = p10; ++ const Vector3& v1 = p20; ++ float d00 = v0.x * v0.x + v0.y * v0.y + v0.z * v0.z; ++ float d01 = v0.x * v1.x + v0.y * v1.y + v0.z * v1.z; ++ float d11 = v1.x * v1.x + v1.y * v1.y + v1.z * v1.z; ++ float denom = d00 * d11 - d01 * d01; ++ float denomr = denom == 0 ? 0.f : 1.f / denom; ++ ++ // precompute gradient factors ++ // these are derived by directly computing derivative of eval(pos) = a0 * u + a1 * v + a2 * w and factoring out common factors that are shared between attributes ++ float gx1 = (d11 * v0.x - d01 * v1.x) * denomr; ++ float gx2 = (d00 * v1.x - d01 * v0.x) * denomr; ++ float gy1 = (d11 * v0.y - d01 * v1.y) * denomr; ++ float gy2 = (d00 * v1.y - d01 * v0.y) * denomr; ++ float gz1 = (d11 * v0.z - d01 * v1.z) * denomr; ++ float gz2 = (d00 * v1.z - d01 * v0.z) * denomr; ++ ++ for (int k = 0; k < ATTRIBUTES; ++k) ++ { ++ float a0 = p0.a[k], a1 = p1.a[k], a2 = p2.a[k]; ++ ++ // compute gradient of eval(pos) for x/y/z/w ++ // the formulas below are obtained by directly computing derivative of eval(pos) = a0 * u + a1 * v + a2 * w ++ float gx = gx1 * (a1 - a0) + gx2 * (a2 - a0); ++ float gy = gy1 * (a1 - a0) + gy2 * (a2 - a0); ++ float gz = gz1 * (a1 - a0) + gz2 * (a2 - a0); ++ float gw = a0 - p0.x * gx - p0.y * gy - p0.z * gz; ++ ++ // quadric encodes (eval(pos)-attr)^2; this means that the resulting expansion needs to compute, for example, pos.x * pos.y * K ++ // since quadrics already encode factors for pos.x * pos.y, we can accumulate almost everything in basic quadric fields ++ Q.a00 += w * (gx * gx); ++ Q.a11 += w * (gy * gy); ++ Q.a22 += w * (gz * gz); ++ ++ Q.a10 += w * (gy * gx); ++ Q.a20 += w * (gz * gx); ++ Q.a21 += w * (gz * gy); ++ ++ Q.b0 += w * (gx * gw); ++ Q.b1 += w * (gy * gw); ++ Q.b2 += w * (gz * gw); ++ ++ Q.c += w * (gw * gw); ++ ++ // the only remaining sum components are ones that depend on attr; these will be addded during error evaluation, see quadricError ++ Q.gx[k] = w * gx; ++ Q.gy[k] = w * gy; ++ Q.gz[k] = w * gz; ++ Q.gw[k] = w * gw; ++ ++#if TRACE > 2 ++ printf("attr%d: %e %e %e\n", ++ k, ++ (gx * p0.x + gy * p0.y + gz * p0.z + gw - a0), ++ (gx * p1.x + gy * p1.y + gz * p1.z + gw - a1), ++ (gx * p2.x + gy * p2.y + gz * p2.z + gw - a2) ++ ); ++#endif ++ } ++} ++#endif ++ + static void fillFaceQuadrics(Quadric* vertex_quadrics, const unsigned int* indices, size_t index_count, const Vector3* vertex_positions, const unsigned int* remap) + { + for (size_t i = 0; i < index_count; i += 3) +@@ -567,6 +686,9 @@ static void fillFaceQuadrics(Quadric* vertex_quadrics, const unsigned int* indic + Quadric Q; + quadricFromTriangle(Q, vertex_positions[i0], vertex_positions[i1], vertex_positions[i2], 1.f); + ++#if ATTRIBUTES ++ quadricUpdateAttributes(Q, vertex_positions[i0], vertex_positions[i1], vertex_positions[i2], Q.w); ++#endif + quadricAdd(vertex_quadrics[remap[i0]], Q); + quadricAdd(vertex_quadrics[remap[i1]], Q); + quadricAdd(vertex_quadrics[remap[i2]], Q); +@@ -1259,13 +1381,19 @@ unsigned int* meshopt_simplifyDebugLoopBack = 0; + #endif + + size_t meshopt_simplify(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) ++{ ++ return meshopt_simplifyWithAttributes(destination, indices, index_count, vertex_positions_data, vertex_count, vertex_positions_stride, target_index_count, target_error, out_result_error, 0, 0, 0); ++} ++ ++size_t meshopt_simplifyWithAttributes(unsigned int* destination, const unsigned int* indices, size_t index_count, const float* vertex_data, size_t vertex_count, size_t vertex_stride, size_t target_index_count, float target_error, float* out_result_error, const float* attributes, const float* attribute_weights, size_t attribute_count) + { + using namespace meshopt; + + assert(index_count % 3 == 0); +- assert(vertex_positions_stride > 0 && vertex_positions_stride <= 256); +- assert(vertex_positions_stride % sizeof(float) == 0); ++ assert(vertex_stride > 0 && vertex_stride <= 256); ++ assert(vertex_stride % sizeof(float) == 0); + assert(target_index_count <= index_count); ++ assert(attribute_count <= ATTRIBUTES); + + meshopt_Allocator allocator; + +@@ -1279,7 +1407,7 @@ size_t meshopt_simplify(unsigned int* destination, const unsigned int* indices, + // build position remap that maps each vertex to the one with identical position + unsigned int* remap = allocator.allocate(vertex_count); + unsigned int* wedge = allocator.allocate(vertex_count); +- buildPositionRemap(remap, wedge, vertex_positions_data, vertex_count, vertex_positions_stride, allocator); ++ buildPositionRemap(remap, wedge, vertex_data, vertex_count, vertex_stride, allocator); + + // classify vertices; vertex kind determines collapse rules, see kCanCollapse + unsigned char* vertex_kind = allocator.allocate(vertex_count); +@@ -1303,7 +1431,21 @@ size_t meshopt_simplify(unsigned int* destination, const unsigned int* indices, + #endif + + Vector3* vertex_positions = allocator.allocate(vertex_count); +- rescalePositions(vertex_positions, vertex_positions_data, vertex_count, vertex_positions_stride); ++ rescalePositions(vertex_positions, vertex_data, vertex_count, vertex_stride); ++ ++#if ATTRIBUTES ++ for (size_t i = 0; i < vertex_count; ++i) ++ { ++ memset(vertex_positions[i].a, 0, sizeof(vertex_positions[i].a)); ++ ++ for (size_t k = 0; k < attribute_count; ++k) ++ { ++ float a = attributes[i * attribute_count + k]; ++ ++ vertex_positions[i].a[k] = a * attribute_weights[k]; ++ } ++ } ++#endif + + Quadric* vertex_quadrics = allocator.allocate(vertex_count); + memset(vertex_quadrics, 0, vertex_count * sizeof(Quadric)); +@@ -1395,7 +1537,9 @@ size_t meshopt_simplify(unsigned int* destination, const unsigned int* indices, + + // result_error is quadratic; we need to remap it back to linear + if (out_result_error) ++ { + *out_result_error = sqrtf(result_error); ++ } + + return result_count; + } diff --git a/thirdparty/meshoptimizer/simplifier.cpp b/thirdparty/meshoptimizer/simplifier.cpp index b2cb589462..059cabb055 100644 --- a/thirdparty/meshoptimizer/simplifier.cpp +++ b/thirdparty/meshoptimizer/simplifier.cpp @@ -20,6 +20,8 @@ #define TRACESTATS(i) (void)0 #endif +#define ATTRIBUTES 8 + // This work is based on: // Michael Garland and Paul S. Heckbert. Surface simplification using quadric error metrics. 1997 // Michael Garland. Quadric-based polygonal surface simplification. 1999 @@ -358,6 +360,10 @@ static void classifyVertices(unsigned char* result, unsigned int* loop, unsigned struct Vector3 { float x, y, z; + +#if ATTRIBUTES + float a[ATTRIBUTES]; +#endif }; static float rescalePositions(Vector3* result, const float* vertex_positions_data, size_t vertex_count, size_t vertex_positions_stride) @@ -414,6 +420,13 @@ struct Quadric float a10, a20, a21; float b0, b1, b2, c; float w; + +#if ATTRIBUTES + float gx[ATTRIBUTES]; + float gy[ATTRIBUTES]; + float gz[ATTRIBUTES]; + float gw[ATTRIBUTES]; +#endif }; struct Collapse @@ -456,6 +469,16 @@ static void quadricAdd(Quadric& Q, const Quadric& R) Q.b2 += R.b2; Q.c += R.c; Q.w += R.w; + +#if ATTRIBUTES + for (int k = 0; k < ATTRIBUTES; ++k) + { + Q.gx[k] += R.gx[k]; + Q.gy[k] += R.gy[k]; + Q.gz[k] += R.gz[k]; + Q.gw[k] += R.gw[k]; + } +#endif } static float quadricError(const Quadric& Q, const Vector3& v) @@ -481,6 +504,17 @@ static float quadricError(const Quadric& Q, const Vector3& v) r += ry * v.y; r += rz * v.z; +#if ATTRIBUTES + // see quadricUpdateAttributes for general derivation; here we need to add the parts of (eval(pos) - attr)^2 that depend on attr + for (int k = 0; k < ATTRIBUTES; ++k) + { + float a = v.a[k]; + + r += a * a * Q.w; + r -= 2 * a * (v.x * Q.gx[k] + v.y * Q.gy[k] + v.z * Q.gz[k] + Q.gw[k]); + } +#endif + float s = Q.w == 0.f ? 0.f : 1.f / Q.w; return fabsf(r) * s; @@ -504,6 +538,13 @@ static void quadricFromPlane(Quadric& Q, float a, float b, float c, float d, flo Q.b2 = c * dw; Q.c = d * dw; Q.w = w; + +#if ATTRIBUTES + memset(Q.gx, 0, sizeof(Q.gx)); + memset(Q.gy, 0, sizeof(Q.gy)); + memset(Q.gz, 0, sizeof(Q.gz)); + memset(Q.gw, 0, sizeof(Q.gw)); +#endif } static void quadricFromPoint(Quadric& Q, float x, float y, float z, float w) @@ -556,6 +597,84 @@ static void quadricFromTriangleEdge(Quadric& Q, const Vector3& p0, const Vector3 quadricFromPlane(Q, normal.x, normal.y, normal.z, -distance, length * weight); } +#if ATTRIBUTES +static void quadricUpdateAttributes(Quadric& Q, const Vector3& p0, const Vector3& p1, const Vector3& p2, float w) +{ + // for each attribute we want to encode the following function into the quadric: + // (eval(pos) - attr)^2 + // where eval(pos) interpolates attribute across the triangle like so: + // eval(pos) = pos.x * gx + pos.y * gy + pos.z * gz + gw + // where gx/gy/gz/gw are gradients + Vector3 p10 = {p1.x - p0.x, p1.y - p0.y, p1.z - p0.z}; + Vector3 p20 = {p2.x - p0.x, p2.y - p0.y, p2.z - p0.z}; + + // we compute gradients using barycentric coordinates; barycentric coordinates can be computed as follows: + // v = (d11 * d20 - d01 * d21) / denom + // w = (d00 * d21 - d01 * d20) / denom + // u = 1 - v - w + // here v0, v1 are triangle edge vectors, v2 is a vector from point to triangle corner, and dij = dot(vi, vj) + const Vector3& v0 = p10; + const Vector3& v1 = p20; + float d00 = v0.x * v0.x + v0.y * v0.y + v0.z * v0.z; + float d01 = v0.x * v1.x + v0.y * v1.y + v0.z * v1.z; + float d11 = v1.x * v1.x + v1.y * v1.y + v1.z * v1.z; + float denom = d00 * d11 - d01 * d01; + float denomr = denom == 0 ? 0.f : 1.f / denom; + + // precompute gradient factors + // these are derived by directly computing derivative of eval(pos) = a0 * u + a1 * v + a2 * w and factoring out common factors that are shared between attributes + float gx1 = (d11 * v0.x - d01 * v1.x) * denomr; + float gx2 = (d00 * v1.x - d01 * v0.x) * denomr; + float gy1 = (d11 * v0.y - d01 * v1.y) * denomr; + float gy2 = (d00 * v1.y - d01 * v0.y) * denomr; + float gz1 = (d11 * v0.z - d01 * v1.z) * denomr; + float gz2 = (d00 * v1.z - d01 * v0.z) * denomr; + + for (int k = 0; k < ATTRIBUTES; ++k) + { + float a0 = p0.a[k], a1 = p1.a[k], a2 = p2.a[k]; + + // compute gradient of eval(pos) for x/y/z/w + // the formulas below are obtained by directly computing derivative of eval(pos) = a0 * u + a1 * v + a2 * w + float gx = gx1 * (a1 - a0) + gx2 * (a2 - a0); + float gy = gy1 * (a1 - a0) + gy2 * (a2 - a0); + float gz = gz1 * (a1 - a0) + gz2 * (a2 - a0); + float gw = a0 - p0.x * gx - p0.y * gy - p0.z * gz; + + // quadric encodes (eval(pos)-attr)^2; this means that the resulting expansion needs to compute, for example, pos.x * pos.y * K + // since quadrics already encode factors for pos.x * pos.y, we can accumulate almost everything in basic quadric fields + Q.a00 += w * (gx * gx); + Q.a11 += w * (gy * gy); + Q.a22 += w * (gz * gz); + + Q.a10 += w * (gy * gx); + Q.a20 += w * (gz * gx); + Q.a21 += w * (gz * gy); + + Q.b0 += w * (gx * gw); + Q.b1 += w * (gy * gw); + Q.b2 += w * (gz * gw); + + Q.c += w * (gw * gw); + + // the only remaining sum components are ones that depend on attr; these will be addded during error evaluation, see quadricError + Q.gx[k] = w * gx; + Q.gy[k] = w * gy; + Q.gz[k] = w * gz; + Q.gw[k] = w * gw; + +#if TRACE > 2 + printf("attr%d: %e %e %e\n", + k, + (gx * p0.x + gy * p0.y + gz * p0.z + gw - a0), + (gx * p1.x + gy * p1.y + gz * p1.z + gw - a1), + (gx * p2.x + gy * p2.y + gz * p2.z + gw - a2) + ); +#endif + } +} +#endif + static void fillFaceQuadrics(Quadric* vertex_quadrics, const unsigned int* indices, size_t index_count, const Vector3* vertex_positions, const unsigned int* remap) { for (size_t i = 0; i < index_count; i += 3) @@ -567,6 +686,9 @@ static void fillFaceQuadrics(Quadric* vertex_quadrics, const unsigned int* indic Quadric Q; quadricFromTriangle(Q, vertex_positions[i0], vertex_positions[i1], vertex_positions[i2], 1.f); +#if ATTRIBUTES + quadricUpdateAttributes(Q, vertex_positions[i0], vertex_positions[i1], vertex_positions[i2], Q.w); +#endif quadricAdd(vertex_quadrics[remap[i0]], Q); quadricAdd(vertex_quadrics[remap[i1]], Q); quadricAdd(vertex_quadrics[remap[i2]], Q); @@ -1259,13 +1381,19 @@ unsigned int* meshopt_simplifyDebugLoopBack = 0; #endif size_t meshopt_simplify(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) +{ + return meshopt_simplifyWithAttributes(destination, indices, index_count, vertex_positions_data, vertex_count, vertex_positions_stride, target_index_count, target_error, out_result_error, 0, 0, 0); +} + +size_t meshopt_simplifyWithAttributes(unsigned int* destination, const unsigned int* indices, size_t index_count, const float* vertex_data, size_t vertex_count, size_t vertex_stride, size_t target_index_count, float target_error, float* out_result_error, const float* attributes, const float* attribute_weights, size_t attribute_count) { using namespace meshopt; assert(index_count % 3 == 0); - assert(vertex_positions_stride > 0 && vertex_positions_stride <= 256); - assert(vertex_positions_stride % sizeof(float) == 0); + assert(vertex_stride > 0 && vertex_stride <= 256); + assert(vertex_stride % sizeof(float) == 0); assert(target_index_count <= index_count); + assert(attribute_count <= ATTRIBUTES); meshopt_Allocator allocator; @@ -1279,7 +1407,7 @@ size_t meshopt_simplify(unsigned int* destination, const unsigned int* indices, // build position remap that maps each vertex to the one with identical position unsigned int* remap = allocator.allocate(vertex_count); unsigned int* wedge = allocator.allocate(vertex_count); - buildPositionRemap(remap, wedge, vertex_positions_data, vertex_count, vertex_positions_stride, allocator); + buildPositionRemap(remap, wedge, vertex_data, vertex_count, vertex_stride, allocator); // classify vertices; vertex kind determines collapse rules, see kCanCollapse unsigned char* vertex_kind = allocator.allocate(vertex_count); @@ -1303,7 +1431,21 @@ size_t meshopt_simplify(unsigned int* destination, const unsigned int* indices, #endif Vector3* vertex_positions = allocator.allocate(vertex_count); - rescalePositions(vertex_positions, vertex_positions_data, vertex_count, vertex_positions_stride); + rescalePositions(vertex_positions, vertex_data, vertex_count, vertex_stride); + +#if ATTRIBUTES + for (size_t i = 0; i < vertex_count; ++i) + { + memset(vertex_positions[i].a, 0, sizeof(vertex_positions[i].a)); + + for (size_t k = 0; k < attribute_count; ++k) + { + float a = attributes[i * attribute_count + k]; + + vertex_positions[i].a[k] = a * attribute_weights[k]; + } + } +#endif Quadric* vertex_quadrics = allocator.allocate(vertex_count); memset(vertex_quadrics, 0, vertex_count * sizeof(Quadric)); @@ -1395,7 +1537,9 @@ size_t meshopt_simplify(unsigned int* destination, const unsigned int* indices, // result_error is quadratic; we need to remap it back to linear if (out_result_error) + { *out_result_error = sqrtf(result_error); + } return result_count; } -- cgit v1.2.3