bgfx/3rdparty/meshoptimizer/demo/main.cpp
Бранимир Караџић 0c5c2fcdcf Updated meshoptimizer.
2019-10-05 10:19:58 -07:00

1050 lines
37 KiB
C++

#include "../src/meshoptimizer.h"
#include <assert.h>
#include <math.h>
#include <stdio.h>
#include <string.h>
#include <time.h>
#include <vector>
#include "../tools/fast_obj.h"
#include "miniz.h"
// This file uses assert() to verify algorithm correctness
#undef NDEBUG
#include <assert.h>
#if defined(__linux__)
double timestamp()
{
timespec ts;
clock_gettime(CLOCK_MONOTONIC, &ts);
return double(ts.tv_sec) + 1e-9 * double(ts.tv_nsec);
}
#elif defined(_WIN32)
struct LARGE_INTEGER
{
__int64 QuadPart;
};
extern "C" __declspec(dllimport) int __stdcall QueryPerformanceCounter(LARGE_INTEGER* lpPerformanceCount);
extern "C" __declspec(dllimport) int __stdcall QueryPerformanceFrequency(LARGE_INTEGER* lpFrequency);
double timestamp()
{
LARGE_INTEGER freq, counter;
QueryPerformanceFrequency(&freq);
QueryPerformanceCounter(&counter);
return double(counter.QuadPart) / double(freq.QuadPart);
}
#else
double timestamp()
{
return double(clock()) / double(CLOCKS_PER_SEC);
}
#endif
const size_t kCacheSize = 16;
struct Vertex
{
float px, py, pz;
float nx, ny, nz;
float tx, ty;
};
struct Mesh
{
std::vector<Vertex> vertices;
std::vector<unsigned int> indices;
};
union Triangle {
Vertex v[3];
char data[sizeof(Vertex) * 3];
};
Mesh parseObj(const char* path, double& reindex)
{
fastObjMesh* obj = fast_obj_read(path);
if (!obj)
{
printf("Error loading %s: file not found\n", path);
return Mesh();
}
size_t total_indices = 0;
for (unsigned int i = 0; i < obj->face_count; ++i)
total_indices += 3 * (obj->face_vertices[i] - 2);
std::vector<Vertex> vertices(total_indices);
size_t vertex_offset = 0;
size_t index_offset = 0;
for (unsigned int i = 0; i < obj->face_count; ++i)
{
for (unsigned int j = 0; j < obj->face_vertices[i]; ++j)
{
fastObjIndex gi = obj->indices[index_offset + j];
Vertex v =
{
obj->positions[gi.p * 3 + 0],
obj->positions[gi.p * 3 + 1],
obj->positions[gi.p * 3 + 2],
obj->normals[gi.n * 3 + 0],
obj->normals[gi.n * 3 + 1],
obj->normals[gi.n * 3 + 2],
obj->texcoords[gi.t * 2 + 0],
obj->texcoords[gi.t * 2 + 1],
};
// triangulate polygon on the fly; offset-3 is always the first polygon vertex
if (j >= 3)
{
vertices[vertex_offset + 0] = vertices[vertex_offset - 3];
vertices[vertex_offset + 1] = vertices[vertex_offset - 1];
vertex_offset += 2;
}
vertices[vertex_offset] = v;
vertex_offset++;
}
index_offset += obj->face_vertices[i];
}
fast_obj_destroy(obj);
reindex = timestamp();
Mesh result;
std::vector<unsigned int> remap(total_indices);
size_t total_vertices = meshopt_generateVertexRemap(&remap[0], NULL, total_indices, &vertices[0], total_indices, sizeof(Vertex));
result.indices.resize(total_indices);
meshopt_remapIndexBuffer(&result.indices[0], NULL, total_indices, &remap[0]);
result.vertices.resize(total_vertices);
meshopt_remapVertexBuffer(&result.vertices[0], &vertices[0], total_indices, sizeof(Vertex), &remap[0]);
return result;
}
bool isMeshValid(const Mesh& mesh)
{
size_t index_count = mesh.indices.size();
size_t vertex_count = mesh.vertices.size();
if (index_count % 3 != 0)
return false;
const unsigned int* indices = &mesh.indices[0];
for (size_t i = 0; i < index_count; ++i)
if (indices[i] >= vertex_count)
return false;
return true;
}
bool rotateTriangle(Triangle& t)
{
int c01 = memcmp(&t.v[0], &t.v[1], sizeof(Vertex));
int c02 = memcmp(&t.v[0], &t.v[2], sizeof(Vertex));
int c12 = memcmp(&t.v[1], &t.v[2], sizeof(Vertex));
if (c12 < 0 && c01 > 0)
{
// 1 is minimum, rotate 012 => 120
Vertex tv = t.v[0];
t.v[0] = t.v[1], t.v[1] = t.v[2], t.v[2] = tv;
}
else if (c02 > 0 && c12 > 0)
{
// 2 is minimum, rotate 012 => 201
Vertex tv = t.v[2];
t.v[2] = t.v[1], t.v[1] = t.v[0], t.v[0] = tv;
}
return c01 != 0 && c02 != 0 && c12 != 0;
}
unsigned int hashRange(const char* key, size_t len)
{
// MurmurHash2
const unsigned int m = 0x5bd1e995;
const int r = 24;
unsigned int h = 0;
while (len >= 4)
{
unsigned int k = *reinterpret_cast<const unsigned int*>(key);
k *= m;
k ^= k >> r;
k *= m;
h *= m;
h ^= k;
key += 4;
len -= 4;
}
return h;
}
unsigned int hashMesh(const Mesh& mesh)
{
size_t triangle_count = mesh.indices.size() / 3;
const Vertex* vertices = &mesh.vertices[0];
const unsigned int* indices = &mesh.indices[0];
unsigned int h1 = 0;
unsigned int h2 = 0;
for (size_t i = 0; i < triangle_count; ++i)
{
Triangle t;
t.v[0] = vertices[indices[i * 3 + 0]];
t.v[1] = vertices[indices[i * 3 + 1]];
t.v[2] = vertices[indices[i * 3 + 2]];
// skip degenerate triangles since some algorithms don't preserve them
if (rotateTriangle(t))
{
unsigned int hash = hashRange(t.data, sizeof(t.data));
h1 ^= hash;
h2 += hash;
}
}
return h1 * 0x5bd1e995 + h2;
}
void optNone(Mesh& mesh)
{
(void)mesh;
}
void optRandomShuffle(Mesh& mesh)
{
size_t triangle_count = mesh.indices.size() / 3;
unsigned int* indices = &mesh.indices[0];
unsigned int rng = 0;
for (size_t i = triangle_count - 1; i > 0; --i)
{
// Fisher-Yates shuffle
size_t j = rng % (i + 1);
unsigned int t;
t = indices[3 * j + 0], indices[3 * j + 0] = indices[3 * i + 0], indices[3 * i + 0] = t;
t = indices[3 * j + 1], indices[3 * j + 1] = indices[3 * i + 1], indices[3 * i + 1] = t;
t = indices[3 * j + 2], indices[3 * j + 2] = indices[3 * i + 2], indices[3 * i + 2] = t;
// LCG RNG, constants from Numerical Recipes
rng = rng * 1664525 + 1013904223;
}
}
void optCache(Mesh& mesh)
{
meshopt_optimizeVertexCache(&mesh.indices[0], &mesh.indices[0], mesh.indices.size(), mesh.vertices.size());
}
void optCacheFifo(Mesh& mesh)
{
meshopt_optimizeVertexCacheFifo(&mesh.indices[0], &mesh.indices[0], mesh.indices.size(), mesh.vertices.size(), kCacheSize);
}
void optOverdraw(Mesh& mesh)
{
// use worst-case ACMR threshold so that overdraw optimizer can sort *all* triangles
// warning: this significantly deteriorates the vertex cache efficiency so it is not advised; look at optComplete for the recommended method
const float kThreshold = 3.f;
meshopt_optimizeOverdraw(&mesh.indices[0], &mesh.indices[0], mesh.indices.size(), &mesh.vertices[0].px, mesh.vertices.size(), sizeof(Vertex), kThreshold);
}
void optFetch(Mesh& mesh)
{
meshopt_optimizeVertexFetch(&mesh.vertices[0], &mesh.indices[0], mesh.indices.size(), &mesh.vertices[0], mesh.vertices.size(), sizeof(Vertex));
}
void optFetchRemap(Mesh& mesh)
{
// this produces results equivalent to optFetch, but can be used to remap multiple vertex streams
std::vector<unsigned int> remap(mesh.vertices.size());
meshopt_optimizeVertexFetchRemap(&remap[0], &mesh.indices[0], mesh.indices.size(), mesh.vertices.size());
meshopt_remapIndexBuffer(&mesh.indices[0], &mesh.indices[0], mesh.indices.size(), &remap[0]);
meshopt_remapVertexBuffer(&mesh.vertices[0], &mesh.vertices[0], mesh.vertices.size(), sizeof(Vertex), &remap[0]);
}
void optComplete(Mesh& mesh)
{
// vertex cache optimization should go first as it provides starting order for overdraw
meshopt_optimizeVertexCache(&mesh.indices[0], &mesh.indices[0], mesh.indices.size(), mesh.vertices.size());
// reorder indices for overdraw, balancing overdraw and vertex cache efficiency
const float kThreshold = 1.01f; // allow up to 1% worse ACMR to get more reordering opportunities for overdraw
meshopt_optimizeOverdraw(&mesh.indices[0], &mesh.indices[0], mesh.indices.size(), &mesh.vertices[0].px, mesh.vertices.size(), sizeof(Vertex), kThreshold);
// vertex fetch optimization should go last as it depends on the final index order
meshopt_optimizeVertexFetch(&mesh.vertices[0], &mesh.indices[0], mesh.indices.size(), &mesh.vertices[0], mesh.vertices.size(), sizeof(Vertex));
}
struct PackedVertex
{
unsigned short px, py, pz;
unsigned short pw; // padding to 4b boundary
signed char nx, ny, nz, nw;
unsigned short tx, ty;
};
void packMesh(std::vector<PackedVertex>& pv, const std::vector<Vertex>& vertices)
{
for (size_t i = 0; i < vertices.size(); ++i)
{
const Vertex& vi = vertices[i];
PackedVertex& pvi = pv[i];
pvi.px = meshopt_quantizeHalf(vi.px);
pvi.py = meshopt_quantizeHalf(vi.py);
pvi.pz = meshopt_quantizeHalf(vi.pz);
pvi.pw = 0;
pvi.nx = char(meshopt_quantizeSnorm(vi.nx, 8));
pvi.ny = char(meshopt_quantizeSnorm(vi.ny, 8));
pvi.nz = char(meshopt_quantizeSnorm(vi.nz, 8));
pvi.nw = 0;
pvi.tx = meshopt_quantizeHalf(vi.tx);
pvi.ty = meshopt_quantizeHalf(vi.ty);
}
}
struct PackedVertexOct
{
unsigned short px, py, pz;
signed char nu, nv; // octahedron encoded normal, aliases .pw
unsigned short tx, ty;
};
void packMesh(std::vector<PackedVertexOct>& pv, const std::vector<Vertex>& vertices)
{
for (size_t i = 0; i < vertices.size(); ++i)
{
const Vertex& vi = vertices[i];
PackedVertexOct& pvi = pv[i];
pvi.px = meshopt_quantizeHalf(vi.px);
pvi.py = meshopt_quantizeHalf(vi.py);
pvi.pz = meshopt_quantizeHalf(vi.pz);
float nsum = fabsf(vi.nx) + fabsf(vi.ny) + fabsf(vi.nz);
float nx = vi.nx / nsum;
float ny = vi.ny / nsum;
float nz = vi.nz;
float nu = nz >= 0 ? nx : (1 - fabsf(ny)) * (nx >= 0 ? 1 : -1);
float nv = nz >= 0 ? ny : (1 - fabsf(nx)) * (ny >= 0 ? 1 : -1);
pvi.nu = char(meshopt_quantizeSnorm(nu, 8));
pvi.nv = char(meshopt_quantizeSnorm(nv, 8));
pvi.tx = meshopt_quantizeHalf(vi.tx);
pvi.ty = meshopt_quantizeHalf(vi.ty);
}
}
void simplify(const Mesh& mesh, float threshold = 0.2f)
{
Mesh lod;
double start = timestamp();
size_t target_index_count = size_t(mesh.indices.size() * threshold);
float target_error = 1e-2f;
lod.indices.resize(mesh.indices.size()); // note: simplify needs space for index_count elements in the destination array, not target_index_count
lod.indices.resize(meshopt_simplify(&lod.indices[0], &mesh.indices[0], mesh.indices.size(), &mesh.vertices[0].px, mesh.vertices.size(), sizeof(Vertex), target_index_count, target_error));
lod.vertices.resize(lod.indices.size() < mesh.vertices.size() ? lod.indices.size() : mesh.vertices.size()); // note: this is just to reduce the cost of resize()
lod.vertices.resize(meshopt_optimizeVertexFetch(&lod.vertices[0], &lod.indices[0], lod.indices.size(), &mesh.vertices[0], mesh.vertices.size(), sizeof(Vertex)));
double end = timestamp();
printf("%-9s: %d triangles => %d triangles in %.2f msec\n",
"Simplify",
int(mesh.indices.size() / 3), int(lod.indices.size() / 3), (end - start) * 1000);
}
void simplifySloppy(const Mesh& mesh, float threshold = 0.2f)
{
Mesh lod;
double start = timestamp();
size_t target_index_count = size_t(mesh.indices.size() * threshold);
lod.indices.resize(target_index_count); // note: simplifySloppy, unlike simplify, is guaranteed to output results that don't exceed the requested target_index_count
lod.indices.resize(meshopt_simplifySloppy(&lod.indices[0], &mesh.indices[0], mesh.indices.size(), &mesh.vertices[0].px, mesh.vertices.size(), sizeof(Vertex), target_index_count));
lod.vertices.resize(lod.indices.size() < mesh.vertices.size() ? lod.indices.size() : mesh.vertices.size()); // note: this is just to reduce the cost of resize()
lod.vertices.resize(meshopt_optimizeVertexFetch(&lod.vertices[0], &lod.indices[0], lod.indices.size(), &mesh.vertices[0], mesh.vertices.size(), sizeof(Vertex)));
double end = timestamp();
printf("%-9s: %d triangles => %d triangles in %.2f msec\n",
"SimplifyS",
int(mesh.indices.size() / 3), int(lod.indices.size() / 3), (end - start) * 1000);
}
void simplifyPoints(const Mesh& mesh, float threshold = 0.2f)
{
double start = timestamp();
size_t target_vertex_count = size_t(mesh.vertices.size() * threshold);
std::vector<unsigned int> indices(target_vertex_count);
indices.resize(meshopt_simplifyPoints(&indices[0], &mesh.vertices[0].px, mesh.vertices.size(), sizeof(Vertex), target_vertex_count));
double end = timestamp();
printf("%-9s: %d points => %d points in %.2f msec\n",
"SimplifyP",
int(mesh.vertices.size()), int(indices.size()), (end - start) * 1000);
}
void simplifyComplete(const Mesh& mesh)
{
static const size_t lod_count = 5;
double start = timestamp();
// generate 4 LOD levels (1-4), with each subsequent LOD using 70% triangles
// note that each LOD uses the same (shared) vertex buffer
std::vector<unsigned int> lods[lod_count];
lods[0] = mesh.indices;
for (size_t i = 1; i < lod_count; ++i)
{
std::vector<unsigned int>& lod = lods[i];
float threshold = powf(0.7f, float(i));
size_t target_index_count = size_t(mesh.indices.size() * threshold) / 3 * 3;
float target_error = 1e-2f;
// we can simplify all the way from base level or from the last result
// simplifying from the base level sometimes produces better results, but simplifying from last level is faster
const std::vector<unsigned int>& source = lods[i - 1];
if (source.size() < target_index_count)
target_index_count = source.size();
lod.resize(source.size());
lod.resize(meshopt_simplify(&lod[0], &source[0], source.size(), &mesh.vertices[0].px, mesh.vertices.size(), sizeof(Vertex), target_index_count, target_error));
}
double middle = timestamp();
// optimize each individual LOD for vertex cache & overdraw
for (size_t i = 0; i < lod_count; ++i)
{
std::vector<unsigned int>& lod = lods[i];
meshopt_optimizeVertexCache(&lod[0], &lod[0], lod.size(), mesh.vertices.size());
meshopt_optimizeOverdraw(&lod[0], &lod[0], lod.size(), &mesh.vertices[0].px, mesh.vertices.size(), sizeof(Vertex), 1.0f);
}
// concatenate all LODs into one IB
// note: the order of concatenation is important - since we optimize the entire IB for vertex fetch,
// putting coarse LODs first makes sure that the vertex range referenced by them is as small as possible
// some GPUs process the entire range referenced by the index buffer region so doing this optimizes the vertex transform
// cost for coarse LODs
// this order also produces much better vertex fetch cache coherency for coarse LODs (since they're essentially optimized first)
// somewhat surprisingly, the vertex fetch cache coherency for fine LODs doesn't seem to suffer that much.
size_t lod_index_offsets[lod_count] = {};
size_t lod_index_counts[lod_count] = {};
size_t total_index_count = 0;
for (int i = lod_count - 1; i >= 0; --i)
{
lod_index_offsets[i] = total_index_count;
lod_index_counts[i] = lods[i].size();
total_index_count += lods[i].size();
}
std::vector<unsigned int> indices(total_index_count);
for (size_t i = 0; i < lod_count; ++i)
{
memcpy(&indices[lod_index_offsets[i]], &lods[i][0], lods[i].size() * sizeof(lods[i][0]));
}
std::vector<Vertex> vertices = mesh.vertices;
// vertex fetch optimization should go last as it depends on the final index order
// note that the order of LODs above affects vertex fetch results
meshopt_optimizeVertexFetch(&vertices[0], &indices[0], indices.size(), &vertices[0], vertices.size(), sizeof(Vertex));
double end = timestamp();
printf("%-9s: %d triangles => %d LOD levels down to %d triangles in %.2f msec, optimized in %.2f msec\n",
"SimplifyC",
int(lod_index_counts[0]) / 3, int(lod_count), int(lod_index_counts[lod_count - 1]) / 3,
(middle - start) * 1000, (end - middle) * 1000);
// for using LOD data at runtime, in addition to vertices and indices you have to save lod_index_offsets/lod_index_counts.
{
meshopt_VertexCacheStatistics vcs0 = meshopt_analyzeVertexCache(&indices[lod_index_offsets[0]], lod_index_counts[0], vertices.size(), kCacheSize, 0, 0);
meshopt_VertexFetchStatistics vfs0 = meshopt_analyzeVertexFetch(&indices[lod_index_offsets[0]], lod_index_counts[0], vertices.size(), sizeof(Vertex));
meshopt_VertexCacheStatistics vcsN = meshopt_analyzeVertexCache(&indices[lod_index_offsets[lod_count - 1]], lod_index_counts[lod_count - 1], vertices.size(), kCacheSize, 0, 0);
meshopt_VertexFetchStatistics vfsN = meshopt_analyzeVertexFetch(&indices[lod_index_offsets[lod_count - 1]], lod_index_counts[lod_count - 1], vertices.size(), sizeof(Vertex));
typedef PackedVertexOct PV;
std::vector<PV> pv(vertices.size());
packMesh(pv, vertices);
std::vector<unsigned char> vbuf(meshopt_encodeVertexBufferBound(vertices.size(), sizeof(PV)));
vbuf.resize(meshopt_encodeVertexBuffer(&vbuf[0], vbuf.size(), &pv[0], vertices.size(), sizeof(PV)));
std::vector<unsigned char> ibuf(meshopt_encodeIndexBufferBound(indices.size(), vertices.size()));
ibuf.resize(meshopt_encodeIndexBuffer(&ibuf[0], ibuf.size(), &indices[0], indices.size()));
printf("%-9s ACMR %f...%f Overfetch %f..%f Codec VB %.1f bits/vertex IB %.1f bits/triangle\n",
"",
vcs0.acmr, vcsN.acmr, vfs0.overfetch, vfsN.overfetch,
double(vbuf.size()) / double(vertices.size()) * 8,
double(ibuf.size()) / double(indices.size() / 3) * 8);
}
}
void optimize(const Mesh& mesh, const char* name, void (*optf)(Mesh& mesh))
{
Mesh copy = mesh;
double start = timestamp();
optf(copy);
double end = timestamp();
assert(isMeshValid(copy));
assert(hashMesh(mesh) == hashMesh(copy));
meshopt_VertexCacheStatistics vcs = meshopt_analyzeVertexCache(&copy.indices[0], copy.indices.size(), copy.vertices.size(), kCacheSize, 0, 0);
meshopt_VertexFetchStatistics vfs = meshopt_analyzeVertexFetch(&copy.indices[0], copy.indices.size(), copy.vertices.size(), sizeof(Vertex));
meshopt_OverdrawStatistics os = meshopt_analyzeOverdraw(&copy.indices[0], copy.indices.size(), &copy.vertices[0].px, copy.vertices.size(), sizeof(Vertex));
meshopt_VertexCacheStatistics vcs_nv = meshopt_analyzeVertexCache(&copy.indices[0], copy.indices.size(), copy.vertices.size(), 32, 32, 32);
meshopt_VertexCacheStatistics vcs_amd = meshopt_analyzeVertexCache(&copy.indices[0], copy.indices.size(), copy.vertices.size(), 14, 64, 128);
meshopt_VertexCacheStatistics vcs_intel = meshopt_analyzeVertexCache(&copy.indices[0], copy.indices.size(), copy.vertices.size(), 128, 0, 0);
printf("%-9s: ACMR %f ATVR %f (NV %f AMD %f Intel %f) Overfetch %f Overdraw %f in %.2f msec\n", name, vcs.acmr, vcs.atvr, vcs_nv.atvr, vcs_amd.atvr, vcs_intel.atvr, vfs.overfetch, os.overdraw, (end - start) * 1000);
}
template <typename T>
size_t compress(const std::vector<T>& data)
{
std::vector<unsigned char> cbuf(tdefl_compress_bound(data.size() * sizeof(T)));
unsigned int flags = tdefl_create_comp_flags_from_zip_params(MZ_DEFAULT_LEVEL, 15, MZ_DEFAULT_STRATEGY);
return tdefl_compress_mem_to_mem(&cbuf[0], cbuf.size(), &data[0], data.size() * sizeof(T), flags);
}
void encodeIndex(const Mesh& mesh)
{
// allocate result outside of the timing loop to exclude memset() from decode timing
std::vector<unsigned int> result(mesh.indices.size());
double start = timestamp();
std::vector<unsigned char> buffer(meshopt_encodeIndexBufferBound(mesh.indices.size(), mesh.vertices.size()));
buffer.resize(meshopt_encodeIndexBuffer(&buffer[0], buffer.size(), &mesh.indices[0], mesh.indices.size()));
double middle = timestamp();
int res = meshopt_decodeIndexBuffer(&result[0], mesh.indices.size(), &buffer[0], buffer.size());
assert(res == 0);
(void)res;
double end = timestamp();
size_t csize = compress(buffer);
for (size_t i = 0; i < mesh.indices.size(); i += 3)
{
assert(
(result[i + 0] == mesh.indices[i + 0] && result[i + 1] == mesh.indices[i + 1] && result[i + 2] == mesh.indices[i + 2]) ||
(result[i + 1] == mesh.indices[i + 0] && result[i + 2] == mesh.indices[i + 1] && result[i + 0] == mesh.indices[i + 2]) ||
(result[i + 2] == mesh.indices[i + 0] && result[i + 0] == mesh.indices[i + 1] && result[i + 1] == mesh.indices[i + 2]));
}
printf("IdxCodec : %.1f bits/triangle (post-deflate %.1f bits/triangle); encode %.2f msec, decode %.2f msec (%.2f GB/s)\n",
double(buffer.size() * 8) / double(mesh.indices.size() / 3),
double(csize * 8) / double(mesh.indices.size() / 3),
(middle - start) * 1000,
(end - middle) * 1000,
(double(result.size() * 4) / (1 << 30)) / (end - middle));
}
template <typename PV>
void packVertex(const Mesh& mesh, const char* pvn)
{
std::vector<PV> pv(mesh.vertices.size());
packMesh(pv, mesh.vertices);
size_t csize = compress(pv);
printf("VtxPack%s : %.1f bits/vertex (post-deflate %.1f bits/vertex)\n", pvn,
double(pv.size() * sizeof(PV) * 8) / double(mesh.vertices.size()),
double(csize * 8) / double(mesh.vertices.size()));
}
template <typename PV>
void encodeVertex(const Mesh& mesh, const char* pvn)
{
std::vector<PV> pv(mesh.vertices.size());
packMesh(pv, mesh.vertices);
// allocate result outside of the timing loop to exclude memset() from decode timing
std::vector<PV> result(mesh.vertices.size());
double start = timestamp();
std::vector<unsigned char> vbuf(meshopt_encodeVertexBufferBound(mesh.vertices.size(), sizeof(PV)));
vbuf.resize(meshopt_encodeVertexBuffer(&vbuf[0], vbuf.size(), &pv[0], mesh.vertices.size(), sizeof(PV)));
double middle = timestamp();
int res = meshopt_decodeVertexBuffer(&result[0], mesh.vertices.size(), sizeof(PV), &vbuf[0], vbuf.size());
assert(res == 0);
(void)res;
double end = timestamp();
assert(memcmp(&pv[0], &result[0], pv.size() * sizeof(PV)) == 0);
size_t csize = compress(vbuf);
printf("VtxCodec%1s: %.1f bits/vertex (post-deflate %.1f bits/vertex); encode %.2f msec, decode %.2f msec (%.2f GB/s)\n", pvn,
double(vbuf.size() * 8) / double(mesh.vertices.size()),
double(csize * 8) / double(mesh.vertices.size()),
(middle - start) * 1000,
(end - middle) * 1000,
(double(result.size() * sizeof(PV)) / (1 << 30)) / (end - middle));
}
void stripify(const Mesh& mesh, bool use_restart)
{
unsigned int restart_index = use_restart ? ~0u : 0;
// note: input mesh is assumed to be optimized for vertex cache and vertex fetch
double start = timestamp();
std::vector<unsigned int> strip(meshopt_stripifyBound(mesh.indices.size()));
strip.resize(meshopt_stripify(&strip[0], &mesh.indices[0], mesh.indices.size(), mesh.vertices.size(), restart_index));
double end = timestamp();
Mesh copy = mesh;
copy.indices.resize(meshopt_unstripify(&copy.indices[0], &strip[0], strip.size(), restart_index));
assert(copy.indices.size() <= meshopt_unstripifyBound(strip.size()));
assert(isMeshValid(copy));
assert(hashMesh(mesh) == hashMesh(copy));
meshopt_VertexCacheStatistics vcs = meshopt_analyzeVertexCache(&copy.indices[0], mesh.indices.size(), mesh.vertices.size(), kCacheSize, 0, 0);
meshopt_VertexCacheStatistics vcs_nv = meshopt_analyzeVertexCache(&copy.indices[0], mesh.indices.size(), mesh.vertices.size(), 32, 32, 32);
meshopt_VertexCacheStatistics vcs_amd = meshopt_analyzeVertexCache(&copy.indices[0], mesh.indices.size(), mesh.vertices.size(), 14, 64, 128);
meshopt_VertexCacheStatistics vcs_intel = meshopt_analyzeVertexCache(&copy.indices[0], mesh.indices.size(), mesh.vertices.size(), 128, 0, 0);
printf("Stripify%c: ACMR %f ATVR %f (NV %f AMD %f Intel %f); %d strip indices (%.1f%%) in %.2f msec\n",
use_restart ? 'R' : ' ',
vcs.acmr, vcs.atvr, vcs_nv.atvr, vcs_amd.atvr, vcs_intel.atvr,
int(strip.size()), double(strip.size()) / double(mesh.indices.size()) * 100,
(end - start) * 1000);
}
void shadow(const Mesh& mesh)
{
// note: input mesh is assumed to be optimized for vertex cache and vertex fetch
double start = timestamp();
// this index buffer can be used for position-only rendering using the same vertex data that the original index buffer uses
std::vector<unsigned int> shadow_indices(mesh.indices.size());
meshopt_generateShadowIndexBuffer(&shadow_indices[0], &mesh.indices[0], mesh.indices.size(), &mesh.vertices[0], mesh.vertices.size(), sizeof(float) * 3, sizeof(Vertex));
double end = timestamp();
// while you can't optimize the vertex data after shadow IB was constructed, you can and should optimize the shadow IB for vertex cache
// this is valuable even if the original indices array was optimized for vertex cache!
meshopt_optimizeVertexCache(&shadow_indices[0], &shadow_indices[0], shadow_indices.size(), mesh.vertices.size());
meshopt_VertexCacheStatistics vcs = meshopt_analyzeVertexCache(&mesh.indices[0], mesh.indices.size(), mesh.vertices.size(), kCacheSize, 0, 0);
meshopt_VertexCacheStatistics vcss = meshopt_analyzeVertexCache(&shadow_indices[0], shadow_indices.size(), mesh.vertices.size(), kCacheSize, 0, 0);
std::vector<char> shadow_flags(mesh.vertices.size());
size_t shadow_vertices = 0;
for (size_t i = 0; i < shadow_indices.size(); ++i)
{
unsigned int index = shadow_indices[i];
shadow_vertices += 1 - shadow_flags[index];
shadow_flags[index] = 1;
}
printf("ShadowIB : ACMR %f (%.2fx improvement); %d shadow vertices (%.2fx improvement) in %.2f msec\n",
vcss.acmr, double(vcs.vertices_transformed) / double(vcss.vertices_transformed),
int(shadow_vertices), double(mesh.vertices.size()) / double(shadow_vertices),
(end - start) * 1000);
}
void meshlets(const Mesh& mesh)
{
const size_t max_vertices = 64;
const size_t max_triangles = 126;
// note: input mesh is assumed to be optimized for vertex cache and vertex fetch
double start = timestamp();
std::vector<meshopt_Meshlet> meshlets(meshopt_buildMeshletsBound(mesh.indices.size(), max_vertices, max_triangles));
meshlets.resize(meshopt_buildMeshlets(&meshlets[0], &mesh.indices[0], mesh.indices.size(), mesh.vertices.size(), max_vertices, max_triangles));
double end = timestamp();
double avg_vertices = 0;
double avg_triangles = 0;
size_t not_full = 0;
for (size_t i = 0; i < meshlets.size(); ++i)
{
const meshopt_Meshlet& m = meshlets[i];
avg_vertices += m.vertex_count;
avg_triangles += m.triangle_count;
not_full += m.vertex_count < max_vertices;
}
avg_vertices /= double(meshlets.size());
avg_triangles /= double(meshlets.size());
printf("Meshlets : %d meshlets (avg vertices %.1f, avg triangles %.1f, not full %d) in %.2f msec\n",
int(meshlets.size()), avg_vertices, avg_triangles, int(not_full), (end - start) * 1000);
float camera[3] = {100, 100, 100};
size_t rejected = 0;
size_t rejected_s8 = 0;
size_t rejected_alt = 0;
size_t rejected_alt_s8 = 0;
size_t accepted = 0;
size_t accepted_s8 = 0;
double startc = timestamp();
for (size_t i = 0; i < meshlets.size(); ++i)
{
meshopt_Bounds bounds = meshopt_computeMeshletBounds(&meshlets[i], &mesh.vertices[0].px, mesh.vertices.size(), sizeof(Vertex));
// trivial accept: we can't ever backface cull this meshlet
accepted += (bounds.cone_cutoff >= 1);
accepted_s8 += (bounds.cone_cutoff_s8 >= 127);
// perspective projection: dot(normalize(cone_apex - camera_position), cone_axis) > cone_cutoff
float mview[3] = {bounds.cone_apex[0] - camera[0], bounds.cone_apex[1] - camera[1], bounds.cone_apex[2] - camera[2]};
float mviewlength = sqrtf(mview[0] * mview[0] + mview[1] * mview[1] + mview[2] * mview[2]);
rejected += mview[0] * bounds.cone_axis[0] + mview[1] * bounds.cone_axis[1] + mview[2] * bounds.cone_axis[2] >= bounds.cone_cutoff * mviewlength;
rejected_s8 += mview[0] * (bounds.cone_axis_s8[0] / 127.f) + mview[1] * (bounds.cone_axis_s8[1] / 127.f) + mview[2] * (bounds.cone_axis_s8[2] / 127.f) >= (bounds.cone_cutoff_s8 / 127.f) * mviewlength;
// alternative formulation for perspective projection that doesn't use apex (and uses cluster bounding sphere instead):
// dot(normalize(center - camera_position), cone_axis) > cone_cutoff + radius / length(center - camera_position)
float cview[3] = {bounds.center[0] - camera[0], bounds.center[1] - camera[1], bounds.center[2] - camera[2]};
float cviewlength = sqrtf(cview[0] * cview[0] + cview[1] * cview[1] + cview[2] * cview[2]);
rejected_alt += cview[0] * bounds.cone_axis[0] + cview[1] * bounds.cone_axis[1] + cview[2] * bounds.cone_axis[2] >= bounds.cone_cutoff * cviewlength + bounds.radius;
rejected_alt_s8 += cview[0] * (bounds.cone_axis_s8[0] / 127.f) + cview[1] * (bounds.cone_axis_s8[1] / 127.f) + cview[2] * (bounds.cone_axis_s8[2] / 127.f) >= (bounds.cone_cutoff_s8 / 127.f) * cviewlength + bounds.radius;
}
double endc = timestamp();
printf("ConeCull : rejected apex %d (%.1f%%) / center %d (%.1f%%), trivially accepted %d (%.1f%%) in %.2f msec\n",
int(rejected), double(rejected) / double(meshlets.size()) * 100,
int(rejected_alt), double(rejected_alt) / double(meshlets.size()) * 100,
int(accepted), double(accepted) / double(meshlets.size()) * 100,
(endc - startc) * 1000);
printf("ConeCull8: rejected apex %d (%.1f%%) / center %d (%.1f%%), trivially accepted %d (%.1f%%) in %.2f msec\n",
int(rejected_s8), double(rejected_s8) / double(meshlets.size()) * 100,
int(rejected_alt_s8), double(rejected_alt_s8) / double(meshlets.size()) * 100,
int(accepted_s8), double(accepted_s8) / double(meshlets.size()) * 100,
(endc - startc) * 1000);
}
void spatialSort(const Mesh& mesh)
{
typedef PackedVertexOct PV;
std::vector<PV> pv(mesh.vertices.size());
packMesh(pv, mesh.vertices);
double start = timestamp();
std::vector<unsigned int> remap(mesh.vertices.size());
meshopt_spatialSortRemap(&remap[0], &mesh.vertices[0].px, mesh.vertices.size(), sizeof(Vertex));
double end = timestamp();
meshopt_remapVertexBuffer(&pv[0], &pv[0], mesh.vertices.size(), sizeof(PV), &remap[0]);
std::vector<unsigned char> vbuf(meshopt_encodeVertexBufferBound(mesh.vertices.size(), sizeof(PV)));
vbuf.resize(meshopt_encodeVertexBuffer(&vbuf[0], vbuf.size(), &pv[0], mesh.vertices.size(), sizeof(PV)));
size_t csize = compress(vbuf);
printf("Spatial : %.1f bits/vertex (post-deflate %.1f bits/vertex); sort %.2f msec\n",
double(vbuf.size() * 8) / double(mesh.vertices.size()),
double(csize * 8) / double(mesh.vertices.size()),
(end - start) * 1000);
}
void spatialSortTriangles(const Mesh& mesh)
{
typedef PackedVertexOct PV;
Mesh copy = mesh;
double start = timestamp();
meshopt_spatialSortTriangles(&copy.indices[0], &copy.indices[0], mesh.indices.size(), &copy.vertices[0].px, copy.vertices.size(), sizeof(Vertex));
double end = timestamp();
meshopt_optimizeVertexCache(&copy.indices[0], &copy.indices[0], copy.indices.size(), copy.vertices.size());
meshopt_optimizeVertexFetch(&copy.vertices[0], &copy.indices[0], copy.indices.size(), &copy.vertices[0], copy.vertices.size(), sizeof(Vertex));
std::vector<PV> pv(mesh.vertices.size());
packMesh(pv, copy.vertices);
std::vector<unsigned char> vbuf(meshopt_encodeVertexBufferBound(mesh.vertices.size(), sizeof(PV)));
vbuf.resize(meshopt_encodeVertexBuffer(&vbuf[0], vbuf.size(), &pv[0], mesh.vertices.size(), sizeof(PV)));
std::vector<unsigned char> ibuf(meshopt_encodeIndexBufferBound(mesh.indices.size(), mesh.vertices.size()));
ibuf.resize(meshopt_encodeIndexBuffer(&ibuf[0], ibuf.size(), &copy.indices[0], mesh.indices.size()));
size_t csizev = compress(vbuf);
size_t csizei = compress(ibuf);
printf("SpatialT : %.1f bits/vertex (post-deflate %.1f bits/vertex); %.1f bits/triangle (post-deflate %.1f bits/triangle); sort %.2f msec\n",
double(vbuf.size() * 8) / double(mesh.vertices.size()),
double(csizev * 8) / double(mesh.vertices.size()),
double(ibuf.size() * 8) / double(mesh.indices.size() / 3),
double(csizei * 8) / double(mesh.indices.size() / 3),
(end - start) * 1000);
}
bool loadMesh(Mesh& mesh, const char* path)
{
double start = timestamp();
double middle;
mesh = parseObj(path, middle);
double end = timestamp();
if (mesh.vertices.empty())
{
printf("Mesh %s is empty, skipping\n", path);
return false;
}
printf("# %s: %d vertices, %d triangles; read in %.2f msec; indexed in %.2f msec\n", path, int(mesh.vertices.size()), int(mesh.indices.size() / 3), (middle - start) * 1000, (end - middle) * 1000);
return true;
}
void processDeinterleaved(const char* path)
{
// Most algorithms in the library work out of the box with deinterleaved geometry, but some require slightly special treatment;
// this code runs a simplified version of complete opt. pipeline using deinterleaved geo. There's no compression performed but you
// can trivially run it by quantizing all elements and running meshopt_encodeVertexBuffer once for each vertex stream.
fastObjMesh* obj = fast_obj_read(path);
if (!obj)
{
printf("Error loading %s: file not found\n", path);
return;
}
size_t total_indices = 0;
for (unsigned int i = 0; i < obj->face_count; ++i)
total_indices += 3 * (obj->face_vertices[i] - 2);
std::vector<float> unindexed_pos(total_indices * 3);
std::vector<float> unindexed_nrm(total_indices * 3);
std::vector<float> unindexed_uv(total_indices * 2);
size_t vertex_offset = 0;
size_t index_offset = 0;
for (unsigned int i = 0; i < obj->face_count; ++i)
{
for (unsigned int j = 0; j < obj->face_vertices[i]; ++j)
{
fastObjIndex gi = obj->indices[index_offset + j];
// triangulate polygon on the fly; offset-3 is always the first polygon vertex
if (j >= 3)
{
memcpy(&unindexed_pos[(vertex_offset + 0) * 3], &unindexed_pos[(vertex_offset - 3) * 3], 3 * sizeof(float));
memcpy(&unindexed_nrm[(vertex_offset + 0) * 3], &unindexed_nrm[(vertex_offset - 3) * 3], 3 * sizeof(float));
memcpy(&unindexed_uv[(vertex_offset + 0) * 2], &unindexed_uv[(vertex_offset - 3) * 2], 2 * sizeof(float));
memcpy(&unindexed_pos[(vertex_offset + 1) * 3], &unindexed_pos[(vertex_offset - 1) * 3], 3 * sizeof(float));
memcpy(&unindexed_nrm[(vertex_offset + 1) * 3], &unindexed_nrm[(vertex_offset - 1) * 3], 3 * sizeof(float));
memcpy(&unindexed_uv[(vertex_offset + 1) * 2], &unindexed_uv[(vertex_offset - 1) * 2], 2 * sizeof(float));
vertex_offset += 2;
}
memcpy(&unindexed_pos[vertex_offset * 3], &obj->positions[gi.p * 3], 3 * sizeof(float));
memcpy(&unindexed_nrm[vertex_offset * 3], &obj->normals[gi.n * 3], 3 * sizeof(float));
memcpy(&unindexed_uv[vertex_offset * 2], &obj->texcoords[gi.t * 2], 2 * sizeof(float));
vertex_offset++;
}
index_offset += obj->face_vertices[i];
}
fast_obj_destroy(obj);
double start = timestamp();
meshopt_Stream streams[] = {
{&unindexed_pos[0], sizeof(float) * 3, sizeof(float) * 3},
{&unindexed_nrm[0], sizeof(float) * 3, sizeof(float) * 3},
{&unindexed_uv[0], sizeof(float) * 2, sizeof(float) * 2},
};
std::vector<unsigned int> remap(total_indices);
size_t total_vertices = meshopt_generateVertexRemapMulti(&remap[0], NULL, total_indices, total_indices, streams, sizeof(streams) / sizeof(streams[0]));
std::vector<unsigned int> indices(total_indices);
meshopt_remapIndexBuffer(&indices[0], NULL, total_indices, &remap[0]);
std::vector<float> pos(total_vertices * 3);
meshopt_remapVertexBuffer(&pos[0], &unindexed_pos[0], total_indices, sizeof(float) * 3, &remap[0]);
std::vector<float> nrm(total_vertices * 3);
meshopt_remapVertexBuffer(&nrm[0], &unindexed_nrm[0], total_indices, sizeof(float) * 3, &remap[0]);
std::vector<float> uv(total_vertices * 2);
meshopt_remapVertexBuffer(&uv[0], &unindexed_uv[0], total_indices, sizeof(float) * 2, &remap[0]);
double reindex = timestamp();
meshopt_optimizeVertexCache(&indices[0], &indices[0], total_indices, total_vertices);
meshopt_optimizeVertexFetchRemap(&remap[0], &indices[0], total_indices, total_vertices);
meshopt_remapVertexBuffer(&pos[0], &pos[0], total_vertices, sizeof(float) * 3, &remap[0]);
meshopt_remapVertexBuffer(&nrm[0], &nrm[0], total_vertices, sizeof(float) * 3, &remap[0]);
meshopt_remapVertexBuffer(&uv[0], &uv[0], total_vertices, sizeof(float) * 2, &remap[0]);
double optimize = timestamp();
// note: since shadow index buffer is computed based on regular vertex/index buffer, the stream points at the indexed data - not unindexed_pos
meshopt_Stream shadow_stream = {&pos[0], sizeof(float) * 3, sizeof(float) * 3};
std::vector<unsigned int> shadow_indices(total_indices);
meshopt_generateShadowIndexBufferMulti(&shadow_indices[0], &indices[0], total_indices, total_vertices, &shadow_stream, 1);
meshopt_optimizeVertexCache(&shadow_indices[0], &shadow_indices[0], total_indices, total_vertices);
double shadow = timestamp();
printf("Deintrlvd: %d vertices, reindexed in %.2f msec, optimized in %.2f msec, generated & optimized shadow indices in %.2f msec\n",
int(total_vertices), (reindex - start) * 1000, (optimize - reindex) * 1000, (shadow - optimize) * 1000);
}
void process(const char* path)
{
Mesh mesh;
if (!loadMesh(mesh, path))
return;
optimize(mesh, "Original", optNone);
optimize(mesh, "Random", optRandomShuffle);
optimize(mesh, "Cache", optCache);
optimize(mesh, "CacheFifo", optCacheFifo);
optimize(mesh, "Overdraw", optOverdraw);
optimize(mesh, "Fetch", optFetch);
optimize(mesh, "FetchMap", optFetchRemap);
optimize(mesh, "Complete", optComplete);
Mesh copy = mesh;
meshopt_optimizeVertexCache(&copy.indices[0], &copy.indices[0], copy.indices.size(), copy.vertices.size());
meshopt_optimizeVertexFetch(&copy.vertices[0], &copy.indices[0], copy.indices.size(), &copy.vertices[0], copy.vertices.size(), sizeof(Vertex));
stripify(copy, false);
stripify(copy, true);
meshlets(copy);
shadow(copy);
encodeIndex(copy);
packVertex<PackedVertex>(copy, "");
encodeVertex<PackedVertex>(copy, "");
encodeVertex<PackedVertexOct>(copy, "O");
simplify(mesh);
simplifySloppy(mesh);
simplifyComplete(mesh);
simplifyPoints(mesh);
spatialSort(mesh);
spatialSortTriangles(mesh);
if (path)
processDeinterleaved(path);
}
void processDev(const char* path)
{
Mesh mesh;
if (!loadMesh(mesh, path))
return;
simplifyPoints(mesh);
}
int main(int argc, char** argv)
{
void runTests();
if (argc == 1)
{
runTests();
}
else
{
if (strcmp(argv[1], "-d") == 0)
{
for (int i = 2; i < argc; ++i)
{
processDev(argv[i]);
}
}
else
{
for (int i = 1; i < argc; ++i)
{
process(argv[i]);
}
runTests();
}
}
}