Scale error in mesh optimizer so it uses absolute scale.

Switch to simplify sloppy for another try.

Update to meshoptimizer e3f53f66e7a35b9b8764bee478589d79e34fa698.
This commit is contained in:
K. S. Ernest (iFire) Lee 2021-01-09 10:04:09 -08:00
parent a33dc4274c
commit 59b61a1f64
8 changed files with 91 additions and 27 deletions

View file

@ -140,6 +140,12 @@ void EditorSceneImporterMesh::generate_lods() {
if (!SurfaceTool::simplify_func) {
return;
}
if (!SurfaceTool::simplify_scale_func) {
return;
}
if (!SurfaceTool::simplify_sloppy_func) {
return;
}
for (int i = 0; i < surfaces.size(); i++) {
if (surfaces[i].primitive != Mesh::PRIMITIVE_TRIANGLES) {
@ -157,20 +163,52 @@ void EditorSceneImporterMesh::generate_lods() {
int min_indices = 10;
int index_target = indices.size() / 2;
print_line("total: " + itos(indices.size()));
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;
while (index_target > min_indices) {
float error;
Vector<int> 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, 1e20, &error);
print_line("shoot for " + itos(index_target) + ", got " + itos(new_len) + " distance " + rtos(error));
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<int> 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
}
new_indices.resize(new_len);
Surface::LOD lod;
lod.distance = error;
lod.distance = error * mesh_scale;
abs_target_error = lod.distance;
if (Math::is_equal_approx(abs_target_error, 0.0f)) {
return;
}
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));
surfaces.write[i].lods.push_back(lod);
index_target /= 2;
}

View file

@ -35,9 +35,13 @@
void register_meshoptimizer_types() {
SurfaceTool::optimize_vertex_cache_func = meshopt_optimizeVertexCache;
SurfaceTool::simplify_func = meshopt_simplify;
SurfaceTool::simplify_scale_func = meshopt_simplifyScale;
SurfaceTool::simplify_sloppy_func = meshopt_simplifySloppy;
}
void unregister_meshoptimizer_types() {
SurfaceTool::optimize_vertex_cache_func = nullptr;
SurfaceTool::simplify_func = nullptr;
SurfaceTool::simplify_scale_func = nullptr;
SurfaceTool::simplify_sloppy_func = nullptr;
}

View file

@ -35,6 +35,8 @@
SurfaceTool::OptimizeVertexCacheFunc SurfaceTool::optimize_vertex_cache_func = nullptr;
SurfaceTool::SimplifyFunc SurfaceTool::simplify_func = nullptr;
SurfaceTool::SimplifyScaleFunc SurfaceTool::simplify_scale_func = nullptr;
SurfaceTool::SimplifySloppyFunc SurfaceTool::simplify_sloppy_func = nullptr;
bool SurfaceTool::Vertex::operator==(const Vertex &p_vertex) const {
if (vertex != p_vertex.vertex) {

View file

@ -78,6 +78,10 @@ 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 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);
static SimplifySloppyFunc simplify_sloppy_func;
private:
struct VertexHasher {

View file

@ -344,7 +344,7 @@ File extracted from upstream release tarball:
## meshoptimizer
- Upstream: https://github.com/zeux/meshoptimizer
- Version: git (e4e43fe36e7a8705e602e7ca2f9fb795ded1d0b9, 2020)
- Version: git (e3f53f66e7a35b9b8764bee478589d79e34fa698, 2021)
- License: MIT
Files extracted from upstream repository:

View file

@ -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)

View file

@ -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 <typename T>
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 <typename T>
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 <typename T>
inline size_t meshopt_stripify(T* destination, const T* indices, size_t index_count, size_t vertex_count, T restart_index);
template <typename T>
@ -855,12 +857,12 @@ inline size_t meshopt_simplify(T* destination, const T* indices, size_t index_co
}
template <typename T>
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<T> in(0, indices, index_count);
meshopt_IndexAdapter<T> out(destination, 0, target_index_count);
meshopt_IndexAdapter<T> 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 <typename T>

View file

@ -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<Vector3>(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<unsigned int>(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;
}