OpenVDB  12.0.0
VoxToNanoVDB.h
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1 // Copyright Contributors to the OpenVDB Project
2 // SPDX-License-Identifier: Apache-2.0
3 
4 #pragma once
5 
6 #include <nanovdb/tools/GridBuilder.h>
7 #include <nanovdb/tools/CreateNanoGrid.h>
8 
9 #define OGT_VOX_IMPLEMENTATION
10 #include "ogt_vox.h"
11 #if defined(_MSC_VER)
12 #include <io.h>
13 #endif
14 
15 namespace detail {
16 
17 inline const ogt_vox_scene* load_vox_scene(const char* filename, uint32_t scene_read_flags = 0)
18 {
19 #if defined(_MSC_VER) && _MSC_VER >= 1400
20  FILE* fp;
21  if (0 != fopen_s(&fp, filename, "rb"))
22  fp = 0;
23 #else
24  FILE* fp = fopen(filename, "rb");
25 #endif
26  if (!fp)
27  return NULL;
28  fseek(fp, 0, SEEK_END);
29  uint32_t buffer_size = ftell(fp);
30  fseek(fp, 0, SEEK_SET);
31  uint8_t* buffer = new uint8_t[buffer_size];
32  size_t bytes = fread(buffer, buffer_size, 1, fp);
33  fclose(fp);
34  const ogt_vox_scene* scene = ogt_vox_read_scene_with_flags(buffer, buffer_size, scene_read_flags);
35  delete[] buffer; // the buffer can be safely deleted once the scene is instantiated.
36  return scene;
37 }
38 
39 inline nanovdb::Vec4f matMult4x4(const float* mat, const nanovdb::Vec4f& rhs)
40 {
41 #define _mat(m, r, c) m[c * 4 + r]
42 
43  return nanovdb::Vec4f(_mat(mat, 0, 0) * rhs[0] + _mat(mat, 0, 1) * rhs[1] + _mat(mat, 0, 2) * rhs[2] + _mat(mat, 0, 3) * rhs[3],
44  _mat(mat, 1, 0) * rhs[0] + _mat(mat, 1, 1) * rhs[1] + _mat(mat, 1, 2) * rhs[2] + _mat(mat, 1, 3) * rhs[3],
45  _mat(mat, 2, 0) * rhs[0] + _mat(mat, 2, 1) * rhs[1] + _mat(mat, 2, 2) * rhs[2] + _mat(mat, 2, 3) * rhs[3],
46  _mat(mat, 3, 0) * rhs[0] + _mat(mat, 3, 1) * rhs[1] + _mat(mat, 3, 2) * rhs[2] + _mat(mat, 3, 3) * rhs[3]);
47 #undef _mat
48 }
49 
50 inline ogt_vox_transform matMult4x4(const float* m, const float* n)
51 {
52 #define _mat(m, c, r) m[c * 4 + r]
53 
54  return ogt_vox_transform{
55  _mat(m, 0, 0) * _mat(n, 0, 0) + _mat(m, 0, 1) * _mat(n, 1, 0) + _mat(m, 0, 2) * _mat(n, 2, 0) + _mat(m, 0, 3) * _mat(n, 3, 0),
56  _mat(m, 0, 0) * _mat(n, 0, 1) + _mat(m, 0, 1) * _mat(n, 1, 1) + _mat(m, 0, 2) * _mat(n, 2, 1) + _mat(m, 0, 3) * _mat(n, 3, 1),
57  _mat(m, 0, 0) * _mat(n, 0, 2) + _mat(m, 0, 1) * _mat(n, 1, 2) + _mat(m, 0, 2) * _mat(n, 2, 2) + _mat(m, 0, 3) * _mat(n, 3, 2),
58  _mat(m, 0, 0) * _mat(n, 0, 3) + _mat(m, 0, 1) * _mat(n, 1, 3) + _mat(m, 0, 2) * _mat(n, 2, 3) + _mat(m, 0, 3) * _mat(n, 3, 3),
59 
60  _mat(m, 1, 0) * _mat(n, 0, 0) + _mat(m, 1, 1) * _mat(n, 1, 0) + _mat(m, 1, 2) * _mat(n, 2, 0) + _mat(m, 1, 3) * _mat(n, 3, 0),
61  _mat(m, 1, 0) * _mat(n, 0, 1) + _mat(m, 1, 1) * _mat(n, 1, 1) + _mat(m, 1, 2) * _mat(n, 2, 1) + _mat(m, 1, 3) * _mat(n, 3, 1),
62  _mat(m, 1, 0) * _mat(n, 0, 2) + _mat(m, 1, 1) * _mat(n, 1, 2) + _mat(m, 1, 2) * _mat(n, 2, 2) + _mat(m, 1, 3) * _mat(n, 3, 2),
63  _mat(m, 1, 0) * _mat(n, 0, 3) + _mat(m, 1, 1) * _mat(n, 1, 3) + _mat(m, 1, 2) * _mat(n, 2, 3) + _mat(m, 1, 3) * _mat(n, 3, 3),
64 
65  _mat(m, 2, 0) * _mat(n, 0, 0) + _mat(m, 2, 1) * _mat(n, 1, 0) + _mat(m, 2, 2) * _mat(n, 2, 0) + _mat(m, 2, 3) * _mat(n, 3, 0),
66  _mat(m, 2, 0) * _mat(n, 0, 1) + _mat(m, 2, 1) * _mat(n, 1, 1) + _mat(m, 2, 2) * _mat(n, 2, 1) + _mat(m, 2, 3) * _mat(n, 3, 1),
67  _mat(m, 2, 0) * _mat(n, 0, 2) + _mat(m, 2, 1) * _mat(n, 1, 2) + _mat(m, 2, 2) * _mat(n, 2, 2) + _mat(m, 2, 3) * _mat(n, 3, 2),
68  _mat(m, 2, 0) * _mat(n, 0, 3) + _mat(m, 2, 1) * _mat(n, 1, 3) + _mat(m, 2, 2) * _mat(n, 2, 3) + _mat(m, 2, 3) * _mat(n, 3, 3),
69 
70  _mat(m, 3, 0) * _mat(n, 0, 0) + _mat(m, 3, 1) * _mat(n, 1, 0) + _mat(m, 3, 2) * _mat(n, 2, 0) + _mat(m, 3, 3) * _mat(n, 3, 0),
71  _mat(m, 3, 0) * _mat(n, 0, 1) + _mat(m, 3, 1) * _mat(n, 1, 1) + _mat(m, 3, 2) * _mat(n, 2, 1) + _mat(m, 3, 3) * _mat(n, 3, 1),
72  _mat(m, 3, 0) * _mat(n, 0, 2) + _mat(m, 3, 1) * _mat(n, 1, 2) + _mat(m, 3, 2) * _mat(n, 2, 2) + _mat(m, 3, 3) * _mat(n, 3, 2),
73  _mat(m, 3, 0) * _mat(n, 0, 3) + _mat(m, 3, 1) * _mat(n, 1, 3) + _mat(m, 3, 2) * _mat(n, 2, 3) + _mat(m, 3, 3) * _mat(n, 3, 3),
74  };
75 #undef _mat
76 }
77 
78 ogt_vox_transform getXform(const ogt_vox_scene& scene, const ogt_vox_instance& instance)
79 {
80  ogt_vox_transform transform = instance.transform; //{1, 0, 0, 0, 0, 1, 0, 0, 0, 0, 1, 0, 0, 0, 0, 1};
81 
82  auto groupIndex = instance.group_index;
83  while (groupIndex != 0 && groupIndex != k_invalid_group_index) {
84  const auto& group = scene.groups[groupIndex];
85  transform = matMult4x4((const float*)&transform, (const float*)&group.transform);
86  groupIndex = group.parent_group_index;
87  }
88 
89  return transform;
90 }
91 
92 bool isVisible(const ogt_vox_scene& scene, const ogt_vox_instance& instance)
93 {
94  if (instance.hidden)
95  return false;
96 
97  if (scene.layers[instance.layer_index].hidden)
98  return false;
99 
100  auto groupIndex = instance.group_index;
101  while (groupIndex != 0 && groupIndex != k_invalid_group_index) {
102  const auto& group = scene.groups[groupIndex];
103  if (group.hidden)
104  return false;
105  if (scene.layers[group.layer_index].hidden)
106  return false;
107  groupIndex = group.parent_group_index;
108  printf("group.parent_group_index = %d\n", groupIndex);
109  }
110  return true;
111 }
112 
113 } // namespace detail
114 
115 /// @brief load a .vox file.
116 template<typename BufferT = nanovdb::HostBuffer>
117 nanovdb::GridHandle<BufferT> convertVoxToNanoVDB(const std::string& inFilename, const std::string& modelName)
118 {
119 #if 0
120  // just debugging the xforms!
121  {
122  ogt_vox_transform translate{1, 0, 0, 0, 0, 1, 0, 0, 0, 0, 1, 0, 0, 2, 0, 1};
123  ogt_vox_transform scale{10, 0, 0, 0, 0, 10, 0, 0, 0, 0, 10, 0, 0, 0, 0, 1};
124  ogt_vox_transform translate2{1, 0, 0, 0, 0, 1, 0, 0, 0, 0, 1, 0, 0, 2, 0, 1};
125  ogt_vox_transform xform = detail::matMult4x4((float*)&scale, (float*)&translate);
126  xform = detail::matMult4x4((float*)&translate2, (float*)&xform);
127  auto v = detail::matMult4x4((float*)&xform, nanovdb::Vec4f(0, 1, 0, 1));
128  std::cout << v[0] << ' ' << v[1] << ' ' << v[2] << '\n';
129  }
130 #endif
131 
132  try {
133  if (const auto* scene = detail::load_vox_scene(inFilename.c_str())) {
134  // we just merge into one grid...
135  nanovdb::tools::build::Grid<nanovdb::math::Rgba8> grid(nanovdb::math::Rgba8(),modelName,nanovdb::GridClass::VoxelVolume);
136  auto acc = grid.getAccessor();
137 
138  auto processModelFn = [&](int modelIndex, const ogt_vox_transform& xform) {
139  const auto* model = scene->models[modelIndex];
140 
141  uint32_t voxel_index = 0;
142  for (uint32_t z = 0; z < model->size_z; ++z) {
143  for (uint32_t y = 0; y < model->size_y; ++y) {
144  for (uint32_t x = 0; x < model->size_x; ++x, ++voxel_index) {
145  if (uint8_t color_index = model->voxel_data[voxel_index]) {
146  ogt_vox_rgba rgba = scene->palette.color[color_index];
147  auto ijk = nanovdb::Coord::Floor(detail::matMult4x4((float*)&xform, nanovdb::Vec4f(x, y, z, 1)));
148  acc.setValue(nanovdb::Coord(ijk[0], ijk[2], -ijk[1]), *reinterpret_cast<nanovdb::math::Rgba8*>(&rgba));
149  }
150  }
151  }
152  }
153  };
154 
155  if (scene->num_instances > 0) {
156  printf("scene processing begin... %d instances\n", scene->num_instances);
157 
158  for (uint32_t instanceIndex = 0; instanceIndex < scene->num_instances; instanceIndex++) {
159  const auto& instance = scene->instances[instanceIndex];
160  uint32_t modelIndex = instance.model_index;
161 
162  //printf("instance[%d].model_index = %d\n", instanceIndex, instance.model_index);
163  //printf("instance[%d].layer_index = %d\n", instanceIndex, instance.layer_index);
164  //printf("instance[%d].group_index = %d\n", instanceIndex, instance.group_index);
165 #if 1
166  if (!detail::isVisible(*scene, instance))
167  continue;
168 
169  auto xform = detail::getXform(*scene, instance);
170 #else
171  auto xform = instance.transform;
172 #endif
173  processModelFn(modelIndex, xform);
174  }
175  } else {
176  printf("scene processing begin... %d models\n", scene->num_models);
177 
178  ogt_vox_transform xform{1, 0, 0, 0, 0, 1, 0, 0, 0, 0, 1, 0, 0, 0, 0, 1};
179 
180  for (uint32_t modelIndex = 0; modelIndex < scene->num_models; modelIndex++) {
181  processModelFn(modelIndex, xform);
182  xform.m30 += 30;
183  }
184  }
185 
186  printf("scene processing end.\n");
187  ogt_vox_destroy_scene(scene);
188  return nanovdb::tools::createNanoGrid(grid);
189  } else {
190  std::ostringstream ss;
191  ss << "Invalid file \"" << inFilename << "\"";
192  throw std::runtime_error(ss.str());
193  }
194  }
195  catch (const std::exception& e) {
196  std::cerr << "An exception occurred: \"" << e.what() << "\"" << std::endl;
197  }
199 }
const ogt_vox_scene * load_vox_scene(const char *filename, uint32_t scene_read_flags=0)
Definition: VoxToNanoVDB.h:17
bool isVisible(const ogt_vox_scene &scene, const ogt_vox_instance &instance)
Definition: VoxToNanoVDB.h:92
nanovdb::GridHandle< BufferT > convertVoxToNanoVDB(const std::string &inFilename, const std::string &modelName)
load a .vox file.
Definition: VoxToNanoVDB.h:117
This class serves to manage a buffer containing one or more NanoVDB Grids.
Definition: GridHandle.h:37
#define _mat(m, r, c)
Definition: VoxToNanoVDB.h:15
MatType scale(const Vec3< typename MatType::value_type > &s)
Return a matrix that scales by s.
Definition: Mat.h:615
int Floor(float x)
Return the floor of x.
Definition: Math.h:848
ogt_vox_transform getXform(const ogt_vox_scene &scene, const ogt_vox_instance &instance)
Definition: VoxToNanoVDB.h:78
nanovdb::Vec4f matMult4x4(const float *mat, const nanovdb::Vec4f &rhs)
Definition: VoxToNanoVDB.h:39