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VolumeToSpheres.h
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1 // Copyright Contributors to the OpenVDB Project
3
4 /// @file tools/VolumeToSpheres.h
5 ///
6 /// @brief Fill a closed level set or fog volume with adaptively-sized spheres.
7
8 #ifndef OPENVDB_TOOLS_VOLUME_TO_SPHERES_HAS_BEEN_INCLUDED
9 #define OPENVDB_TOOLS_VOLUME_TO_SPHERES_HAS_BEEN_INCLUDED
10
12 #include <openvdb/math/Math.h>
13 #include "Morphology.h" // for erodeActiveValues()
14 #include "PointScatter.h"
15 #include "LevelSetRebuild.h"
16 #include "LevelSetUtil.h"
17 #include "VolumeToMesh.h"
18 #include <openvdb/openvdb.h>
19
20 #include <tbb/blocked_range.h>
21 #include <tbb/parallel_for.h>
22 #include <tbb/parallel_reduce.h>
23
24 #include <algorithm> // for std::min(), std::max()
25 #include <cmath> // for std::sqrt()
26 #include <limits> // for std::numeric_limits
27 #include <memory>
28 #include <random>
29 #include <utility> // for std::pair
30 #include <vector>
31
32
33 namespace openvdb {
35 namespace OPENVDB_VERSION_NAME {
36 namespace tools {
37
38 /// @brief Fill a closed level set or fog volume with adaptively-sized spheres.
39 ///
40 /// @param grid a scalar grid that defines the surface to be filled with spheres
41 /// @param spheres an output array of 4-tuples representing the fitted spheres<BR>
42 /// The first three components of each tuple specify the sphere center,
43 /// and the fourth specifies the radius.
44 /// The spheres are ordered by radius, from largest to smallest.
45 /// @param sphereCount lower and upper bounds on the number of spheres to be generated<BR>
46 /// The actual number will be somewhere within the bounds.
47 /// @param overlapping toggle to allow spheres to overlap/intersect
48 /// @param minRadius the smallest allowable sphere size, in voxel units<BR>
49 /// @param maxRadius the largest allowable sphere size, in voxel units
50 /// @param isovalue the voxel value that determines the surface of the volume<BR>
51 /// The default value of zero works for signed distance fields,
52 /// while fog volumes require a larger positive value
53 /// (0.5 is a good initial guess).
54 /// @param instanceCount the number of interior points to consider for the sphere placement<BR>
55 /// Increasing this count increases the chances of finding optimal
56 /// sphere sizes.
57 /// @param interrupter pointer to an object adhering to the util::NullInterrupter interface
58 ///
59 /// @note The minimum sphere count takes precedence over the minimum radius.
60 template<typename GridT, typename InterrupterT = util::NullInterrupter>
61 void
63  const GridT& grid,
64  std::vector<openvdb::Vec4s>& spheres,
65  const Vec2i& sphereCount = Vec2i(1, 50),
66  bool overlapping = false,
69  float isovalue = 0.0,
70  int instanceCount = 10000,
71  InterrupterT* interrupter = nullptr);
72
73
74 ////////////////////////////////////////
75
76
77 /// @brief Accelerated closest surface point queries for narrow band level sets
78 /// @details Supports queries that originate at arbitrary world-space locations,
79 /// is not confined to the narrow band region of the input volume geometry.
80 template<typename GridT>
82 {
83 public:
84  using Ptr = std::unique_ptr<ClosestSurfacePoint>;
85  using TreeT = typename GridT::TreeType;
86  using BoolTreeT = typename TreeT::template ValueConverter<bool>::Type;
87  using Index32TreeT = typename TreeT::template ValueConverter<Index32>::Type;
88  using Int16TreeT = typename TreeT::template ValueConverter<Int16>::Type;
89
90  /// @brief Extract surface points and construct a spatial acceleration structure.
91  ///
92  /// @return a null pointer if the initialization fails for any reason,
93  /// otherwise a unique pointer to a newly-allocated ClosestSurfacePoint object.
94  ///
95  /// @param grid a scalar level set or fog volume
96  /// @param isovalue the voxel value that determines the surface of the volume
97  /// The default value of zero works for signed distance fields,
98  /// while fog volumes require a larger positive value
99  /// (0.5 is a good initial guess).
100  /// @param interrupter pointer to an object adhering to the util::NullInterrupter interface.
101  template<typename InterrupterT = util::NullInterrupter>
102  static Ptr create(const GridT& grid, float isovalue = 0.0,
103  InterrupterT* interrupter = nullptr);
104
105  /// @brief Compute the distance from each input point to its closest surface point.
106  /// @param points input list of points in world space
107  /// @param distances output list of closest surface point distances
108  bool search(const std::vector<Vec3R>& points, std::vector<float>& distances);
109
110  /// @brief Overwrite each input point with its closest surface point.
111  /// @param points input/output list of points in world space
112  /// @param distances output list of closest surface point distances
113  bool searchAndReplace(std::vector<Vec3R>& points, std::vector<float>& distances);
114
115  /// @brief Tree accessor
116  const Index32TreeT& indexTree() const { return *mIdxTreePt; }
117  /// @brief Tree accessor
118  const Int16TreeT& signTree() const { return *mSignTreePt; }
119
120 private:
121  using Index32LeafT = typename Index32TreeT::LeafNodeType;
122  using IndexRange = std::pair<size_t, size_t>;
123
124  std::vector<Vec4R> mLeafBoundingSpheres, mNodeBoundingSpheres;
125  std::vector<IndexRange> mLeafRanges;
126  std::vector<const Index32LeafT*> mLeafNodes;
127  PointList mSurfacePointList;
128  size_t mPointListSize = 0, mMaxNodeLeafs = 0;
129  typename Index32TreeT::Ptr mIdxTreePt;
130  typename Int16TreeT::Ptr mSignTreePt;
131
132  ClosestSurfacePoint() = default;
133  template<typename InterrupterT = util::NullInterrupter>
134  bool initialize(const GridT&, float isovalue, InterrupterT*);
135  bool search(std::vector<Vec3R>&, std::vector<float>&, bool transformPoints);
136 };
137
138
139 ////////////////////////////////////////
140
141
142 // Internal utility methods
143
144 /// @cond OPENVDB_DOCS_INTERNAL
145
146 namespace v2s_internal {
147
148 struct PointAccessor
149 {
150  PointAccessor(std::vector<Vec3R>& points)
151  : mPoints(points)
152  {
153  }
154
156  {
157  mPoints.push_back(pos);
158  }
159 private:
160  std::vector<Vec3R>& mPoints;
161 };
162
163
164 template<typename Index32LeafT>
165 class LeafOp
166 {
167 public:
168
169  LeafOp(std::vector<Vec4R>& leafBoundingSpheres,
170  const std::vector<const Index32LeafT*>& leafNodes,
171  const math::Transform& transform,
172  const PointList& surfacePointList);
173
174  void run(bool threaded = true);
175
176
177  void operator()(const tbb::blocked_range<size_t>&) const;
178
179 private:
180  std::vector<Vec4R>& mLeafBoundingSpheres;
181  const std::vector<const Index32LeafT*>& mLeafNodes;
182  const math::Transform& mTransform;
183  const PointList& mSurfacePointList;
184 };
185
186 template<typename Index32LeafT>
187 LeafOp<Index32LeafT>::LeafOp(
188  std::vector<Vec4R>& leafBoundingSpheres,
189  const std::vector<const Index32LeafT*>& leafNodes,
190  const math::Transform& transform,
191  const PointList& surfacePointList)
192  : mLeafBoundingSpheres(leafBoundingSpheres)
193  , mLeafNodes(leafNodes)
194  , mTransform(transform)
195  , mSurfacePointList(surfacePointList)
196 {
197 }
198
199 template<typename Index32LeafT>
200 void
202 {
204  tbb::parallel_for(tbb::blocked_range<size_t>(0, mLeafNodes.size()), *this);
205  } else {
206  (*this)(tbb::blocked_range<size_t>(0, mLeafNodes.size()));
207  }
208 }
209
210 template<typename Index32LeafT>
211 void
212 LeafOp<Index32LeafT>::operator()(const tbb::blocked_range<size_t>& range) const
213 {
214  typename Index32LeafT::ValueOnCIter iter;
215  Vec3s avg;
216
217  for (size_t n = range.begin(); n != range.end(); ++n) {
218  avg[0] = 0.0;
219  avg[1] = 0.0;
220  avg[2] = 0.0;
221
222  int count = 0;
223  for (iter = mLeafNodes[n]->cbeginValueOn(); iter; ++iter) {
224  avg += mSurfacePointList[iter.getValue()];
225  ++count;
226  }
227  if (count > 1) avg *= float(1.0 / double(count));
228
229  float maxDist = 0.0;
230  for (iter = mLeafNodes[n]->cbeginValueOn(); iter; ++iter) {
231  float tmpDist = (mSurfacePointList[iter.getValue()] - avg).lengthSqr();
232  if (tmpDist > maxDist) maxDist = tmpDist;
233  }
234
235  Vec4R& sphere = mLeafBoundingSpheres[n];
236  sphere[0] = avg[0];
237  sphere[1] = avg[1];
238  sphere[2] = avg[2];
240  }
241 }
242
243
244 class NodeOp
245 {
246 public:
247  using IndexRange = std::pair<size_t, size_t>;
248
249  NodeOp(std::vector<Vec4R>& nodeBoundingSpheres,
250  const std::vector<IndexRange>& leafRanges,
251  const std::vector<Vec4R>& leafBoundingSpheres);
252
253  inline void run(bool threaded = true);
254
255  inline void operator()(const tbb::blocked_range<size_t>&) const;
256
257 private:
258  std::vector<Vec4R>& mNodeBoundingSpheres;
259  const std::vector<IndexRange>& mLeafRanges;
260  const std::vector<Vec4R>& mLeafBoundingSpheres;
261 };
262
263 inline
264 NodeOp::NodeOp(std::vector<Vec4R>& nodeBoundingSpheres,
265  const std::vector<IndexRange>& leafRanges,
266  const std::vector<Vec4R>& leafBoundingSpheres)
267  : mNodeBoundingSpheres(nodeBoundingSpheres)
268  , mLeafRanges(leafRanges)
269  , mLeafBoundingSpheres(leafBoundingSpheres)
270 {
271 }
272
273 inline void
275 {
277  tbb::parallel_for(tbb::blocked_range<size_t>(0, mLeafRanges.size()), *this);
278  } else {
279  (*this)(tbb::blocked_range<size_t>(0, mLeafRanges.size()));
280  }
281 }
282
283 inline void
284 NodeOp::operator()(const tbb::blocked_range<size_t>& range) const
285 {
286  Vec3d avg, pos;
287
288  for (size_t n = range.begin(); n != range.end(); ++n) {
289
290  avg[0] = 0.0;
291  avg[1] = 0.0;
292  avg[2] = 0.0;
293
294  int count = int(mLeafRanges[n].second) - int(mLeafRanges[n].first);
295
296  for (size_t i = mLeafRanges[n].first; i < mLeafRanges[n].second; ++i) {
297  avg[0] += mLeafBoundingSpheres[i][0];
298  avg[1] += mLeafBoundingSpheres[i][1];
299  avg[2] += mLeafBoundingSpheres[i][2];
300  }
301
302  if (count > 1) avg *= float(1.0 / double(count));
303
304
305  double maxDist = 0.0;
306
307  for (size_t i = mLeafRanges[n].first; i < mLeafRanges[n].second; ++i) {
308  pos[0] = mLeafBoundingSpheres[i][0];
309  pos[1] = mLeafBoundingSpheres[i][1];
310  pos[2] = mLeafBoundingSpheres[i][2];
311  const auto radiusSqr = mLeafBoundingSpheres[i][3];
312
313  double tmpDist = (pos - avg).lengthSqr() + radiusSqr;
314  if (tmpDist > maxDist) maxDist = tmpDist;
315  }
316
317  Vec4R& sphere = mNodeBoundingSpheres[n];
318
319  sphere[0] = avg[0];
320  sphere[1] = avg[1];
321  sphere[2] = avg[2];
323  }
324 }
325
326
327 ////////////////////////////////////////
328
329
330 template<typename Index32LeafT>
331 class ClosestPointDist
332 {
333 public:
334  using IndexRange = std::pair<size_t, size_t>;
335
336  ClosestPointDist(
337  std::vector<Vec3R>& instancePoints,
338  std::vector<float>& instanceDistances,
339  const PointList& surfacePointList,
340  const std::vector<const Index32LeafT*>& leafNodes,
341  const std::vector<IndexRange>& leafRanges,
342  const std::vector<Vec4R>& leafBoundingSpheres,
343  const std::vector<Vec4R>& nodeBoundingSpheres,
344  size_t maxNodeLeafs,
345  bool transformPoints = false);
346
347
348  void run(bool threaded = true);
349
350
351  void operator()(const tbb::blocked_range<size_t>&) const;
352
353 private:
354
355  void evalLeaf(size_t index, const Index32LeafT& leaf) const;
356  void evalNode(size_t pointIndex, size_t nodeIndex) const;
357
358
359  std::vector<Vec3R>& mInstancePoints;
360  std::vector<float>& mInstanceDistances;
361
362  const PointList& mSurfacePointList;
363
364  const std::vector<const Index32LeafT*>& mLeafNodes;
365  const std::vector<IndexRange>& mLeafRanges;
366  const std::vector<Vec4R>& mLeafBoundingSpheres;
367  const std::vector<Vec4R>& mNodeBoundingSpheres;
368
369  std::vector<float> mLeafDistances, mNodeDistances;
370
371  const bool mTransformPoints;
372  size_t mClosestPointIndex;
373 };// ClosestPointDist
374
375
376 template<typename Index32LeafT>
377 ClosestPointDist<Index32LeafT>::ClosestPointDist(
378  std::vector<Vec3R>& instancePoints,
379  std::vector<float>& instanceDistances,
380  const PointList& surfacePointList,
381  const std::vector<const Index32LeafT*>& leafNodes,
382  const std::vector<IndexRange>& leafRanges,
383  const std::vector<Vec4R>& leafBoundingSpheres,
384  const std::vector<Vec4R>& nodeBoundingSpheres,
385  size_t maxNodeLeafs,
386  bool transformPoints)
387  : mInstancePoints(instancePoints)
388  , mInstanceDistances(instanceDistances)
389  , mSurfacePointList(surfacePointList)
390  , mLeafNodes(leafNodes)
391  , mLeafRanges(leafRanges)
392  , mLeafBoundingSpheres(leafBoundingSpheres)
393  , mNodeBoundingSpheres(nodeBoundingSpheres)
394  , mLeafDistances(maxNodeLeafs, 0.0)
395  , mNodeDistances(leafRanges.size(), 0.0)
396  , mTransformPoints(transformPoints)
397  , mClosestPointIndex(0)
398 {
399 }
400
401
402 template<typename Index32LeafT>
403 void
405 {
407  tbb::parallel_for(tbb::blocked_range<size_t>(0, mInstancePoints.size()), *this);
408  } else {
409  (*this)(tbb::blocked_range<size_t>(0, mInstancePoints.size()));
410  }
411 }
412
413 template<typename Index32LeafT>
414 void
415 ClosestPointDist<Index32LeafT>::evalLeaf(size_t index, const Index32LeafT& leaf) const
416 {
417  typename Index32LeafT::ValueOnCIter iter;
418  const Vec3s center = mInstancePoints[index];
419  size_t& closestPointIndex = const_cast<size_t&>(mClosestPointIndex);
420
421  for (iter = leaf.cbeginValueOn(); iter; ++iter) {
422
423  const Vec3s& point = mSurfacePointList[iter.getValue()];
424  float tmpDist = (point - center).lengthSqr();
425
426  if (tmpDist < mInstanceDistances[index]) {
427  mInstanceDistances[index] = tmpDist;
428  closestPointIndex = iter.getValue();
429  }
430  }
431 }
432
433
434 template<typename Index32LeafT>
435 void
436 ClosestPointDist<Index32LeafT>::evalNode(size_t pointIndex, size_t nodeIndex) const
437 {
438  if (nodeIndex >= mLeafRanges.size()) return;
439
440  const Vec3R& pos = mInstancePoints[pointIndex];
441  float minDist = mInstanceDistances[pointIndex];
442  size_t minDistIdx = 0;
443  Vec3R center;
444  bool updatedDist = false;
445
446  for (size_t i = mLeafRanges[nodeIndex].first, n = 0;
447  i < mLeafRanges[nodeIndex].second; ++i, ++n)
448  {
449  float& distToLeaf = const_cast<float&>(mLeafDistances[n]);
450
451  center[0] = mLeafBoundingSpheres[i][0];
452  center[1] = mLeafBoundingSpheres[i][1];
453  center[2] = mLeafBoundingSpheres[i][2];
454  const auto radiusSqr = mLeafBoundingSpheres[i][3];
455
456  distToLeaf = float(std::max(0.0, (pos - center).lengthSqr() - radiusSqr));
457
458  if (distToLeaf < minDist) {
459  minDist = distToLeaf;
460  minDistIdx = i;
461  updatedDist = true;
462  }
463  }
464
465  if (!updatedDist) return;
466
467  evalLeaf(pointIndex, *mLeafNodes[minDistIdx]);
468
469  for (size_t i = mLeafRanges[nodeIndex].first, n = 0;
470  i < mLeafRanges[nodeIndex].second; ++i, ++n)
471  {
472  if (mLeafDistances[n] < mInstanceDistances[pointIndex] && i != minDistIdx) {
473  evalLeaf(pointIndex, *mLeafNodes[i]);
474  }
475  }
476 }
477
478
479 template<typename Index32LeafT>
480 void
481 ClosestPointDist<Index32LeafT>::operator()(const tbb::blocked_range<size_t>& range) const
482 {
483  Vec3R center;
484  for (size_t n = range.begin(); n != range.end(); ++n) {
485
486  const Vec3R& pos = mInstancePoints[n];
487  float minDist = mInstanceDistances[n];
488  size_t minDistIdx = 0;
489
490  for (size_t i = 0, I = mNodeDistances.size(); i < I; ++i) {
491  float& distToNode = const_cast<float&>(mNodeDistances[i]);
492
493  center[0] = mNodeBoundingSpheres[i][0];
494  center[1] = mNodeBoundingSpheres[i][1];
495  center[2] = mNodeBoundingSpheres[i][2];
496  const auto radiusSqr = mNodeBoundingSpheres[i][3];
497
498  distToNode = float(std::max(0.0, (pos - center).lengthSqr() - radiusSqr));
499
500  if (distToNode < minDist) {
501  minDist = distToNode;
502  minDistIdx = i;
503  }
504  }
505
506  evalNode(n, minDistIdx);
507
508  for (size_t i = 0, I = mNodeDistances.size(); i < I; ++i) {
509  if (mNodeDistances[i] < mInstanceDistances[n] && i != minDistIdx) {
510  evalNode(n, i);
511  }
512  }
513
514  mInstanceDistances[n] = std::sqrt(mInstanceDistances[n]);
515
516  if (mTransformPoints) mInstancePoints[n] = mSurfacePointList[mClosestPointIndex];
517  }
518 }
519
520
521 class UpdatePoints
522 {
523 public:
524  UpdatePoints(
525  const Vec4s& sphere,
526  const std::vector<Vec3R>& points,
527  std::vector<float>& distances,
529  bool overlapping);
530
532  int index() const { return mIndex; }
533
534  inline void run(bool threaded = true);
535
536
537  UpdatePoints(UpdatePoints&, tbb::split);
538  inline void operator()(const tbb::blocked_range<size_t>& range);
539  void join(const UpdatePoints& rhs)
540  {
543  mIndex = rhs.mIndex;
544  }
545  }
546
547 private:
548  const Vec4s& mSphere;
549  const std::vector<Vec3R>& mPoints;
550  std::vector<float>& mDistances;
552  bool mOverlapping;
554  int mIndex;
555 };
556
557 inline
558 UpdatePoints::UpdatePoints(
559  const Vec4s& sphere,
560  const std::vector<Vec3R>& points,
561  std::vector<float>& distances,
563  bool overlapping)
564  : mSphere(sphere)
565  , mPoints(points)
566  , mDistances(distances)
568  , mOverlapping(overlapping)
570  , mIndex(0)
571 {
572 }
573
574 inline
575 UpdatePoints::UpdatePoints(UpdatePoints& rhs, tbb::split)
576  : mSphere(rhs.mSphere)
577  , mPoints(rhs.mPoints)
578  , mDistances(rhs.mDistances)
580  , mOverlapping(rhs.mOverlapping)
582  , mIndex(rhs.mIndex)
583 {
584 }
585
586 inline void
588 {
590  tbb::parallel_reduce(tbb::blocked_range<size_t>(0, mPoints.size()), *this);
591  } else {
592  (*this)(tbb::blocked_range<size_t>(0, mPoints.size()));
593  }
594 }
595
596 inline void
597 UpdatePoints::operator()(const tbb::blocked_range<size_t>& range)
598 {
599  Vec3s pos;
600  for (size_t n = range.begin(); n != range.end(); ++n) {
602
603  pos.x() = float(mPoints[n].x()) - mSphere[0];
604  pos.y() = float(mPoints[n].y()) - mSphere[1];
605  pos.z() = float(mPoints[n].z()) - mSphere[2];
606
607  float dist = pos.length();
608
609  if (dist < mSphere[3]) {
611  continue;
612  }
613
614  if (!mOverlapping) {
615  mDistances[n] = std::min(mDistances[n], (dist - mSphere[3]));
616  }
617
618  if (mDistances[n] > mRadius) {
620  mIndex = int(n);
621  }
622  }
623 }
624
625
626 } // namespace v2s_internal
627
628 /// @endcond
629
630 ////////////////////////////////////////
631
632
633 template<typename GridT, typename InterrupterT>
634 void
636  const GridT& grid,
637  std::vector<openvdb::Vec4s>& spheres,
638  const Vec2i& sphereCount,
639  bool overlapping,
642  float isovalue,
643  int instanceCount,
644  InterrupterT* interrupter)
645 {
646  spheres.clear();
647
648  if (grid.empty()) return;
649
650  const int
651  minSphereCount = sphereCount[0],
652  maxSphereCount = sphereCount[1];
653  if ((minSphereCount > maxSphereCount) || (maxSphereCount < 1)) {
654  OPENVDB_LOG_WARN("fillWithSpheres: minimum sphere count ("
655  << minSphereCount << ") exceeds maximum count (" << maxSphereCount << ")");
656  return;
657  }
658  spheres.reserve(maxSphereCount);
659
660  auto gridPtr = grid.copy(); // shallow copy
661
662  if (gridPtr->getGridClass() == GRID_LEVEL_SET) {
663  // Clamp the isovalue to the level set's background value minus epsilon.
664  // (In a valid narrow-band level set, all voxels, including background voxels,
665  // have values less than or equal to the background value, so an isovalue
666  // greater than or equal to the background value would produce a mask with
667  // effectively infinite extent.)
668  isovalue = std::min(isovalue,
669  static_cast<float>(gridPtr->background() - math::Tolerance<float>::value()));
670  } else if (gridPtr->getGridClass() == GRID_FOG_VOLUME) {
671  // Clamp the isovalue of a fog volume between epsilon and one,
672  // again to avoid a mask with infinite extent. (Recall that
673  // fog volume voxel values vary from zero outside to one inside.)
674  isovalue = math::Clamp(isovalue, math::Tolerance<float>::value(), 1.f);
675  }
676
677  // ClosestSurfacePoint is inaccurate for small grids.
678  // Resample the input grid if it is too small.
679  auto numVoxels = gridPtr->activeVoxelCount();
680  if (numVoxels < 10000) {
681  const auto scale = 1.0 / math::Cbrt(2.0 * 10000.0 / double(numVoxels));
682  auto scaledXform = gridPtr->transform().copy();
683  scaledXform->preScale(scale);
684
685  auto newGridPtr = levelSetRebuild(*gridPtr, isovalue,
686  LEVEL_SET_HALF_WIDTH, LEVEL_SET_HALF_WIDTH, scaledXform.get(), interrupter);
687
688  const auto newNumVoxels = newGridPtr->activeVoxelCount();
689  if (newNumVoxels > numVoxels) {
690  OPENVDB_LOG_DEBUG_RUNTIME("fillWithSpheres: resampled input grid from "
691  << numVoxels << " voxel" << (numVoxels == 1 ? "" : "s")
692  << " to " << newNumVoxels << " voxel" << (newNumVoxels == 1 ? "" : "s"));
693  gridPtr = newGridPtr;
694  numVoxels = newNumVoxels;
695  }
696  }
697
698  const bool addNarrowBandPoints = (numVoxels < 10000);
699  int instances = std::max(instanceCount, maxSphereCount);
700
701  using TreeT = typename GridT::TreeType;
702  using BoolTreeT = typename TreeT::template ValueConverter<bool>::Type;
703  using Int16TreeT = typename TreeT::template ValueConverter<Int16>::Type;
704
705  using RandGen = std::mersenne_twister_engine<uint32_t, 32, 351, 175, 19,
706  0xccab8ee7, 11, 0xffffffff, 7, 0x31b6ab00, 15, 0xffe50000, 17, 1812433253>; // mt11213b
707  RandGen mtRand(/*seed=*/0);
708
709  const TreeT& tree = gridPtr->tree();
710  math::Transform transform = gridPtr->transform();
711
712  std::vector<Vec3R> instancePoints;
713  {
714  // Compute a mask of the voxels enclosed by the isosurface.
716  if (gridPtr->getGridClass() == GRID_LEVEL_SET) {
718  } else {
719  // For non-level-set grids, the interior mask comprises the active voxels.
723  }
724
725  if (interrupter && interrupter->wasInterrupted()) return;
726
727  // If the interior mask is small and eroding it results in an empty grid,
728  // use the uneroded mask instead. (But if the minimum sphere count is zero,
729  // then eroding away the mask is acceptable.)
730  if (!addNarrowBandPoints || (minSphereCount <= 0)) {
733  } else {
739  }
740
741  // Scatter candidate sphere centroids (instancePoints)
742  instancePoints.reserve(instances);
743  v2s_internal::PointAccessor ptnAcc(instancePoints);
744
745  const auto scatterCount = Index64(addNarrowBandPoints ? (instances / 2) : instances);
746
748  ptnAcc, scatterCount, mtRand, 1.0, interrupter);
750  }
751
752  if (interrupter && interrupter->wasInterrupted()) return;
753
754  auto csp = ClosestSurfacePoint<GridT>::create(*gridPtr, isovalue, interrupter);
755  if (!csp) return;
756
757  // Add extra instance points in the interior narrow band.
758  if (instancePoints.size() < size_t(instances)) {
759  const Int16TreeT& signTree = csp->signTree();
760  for (auto leafIt = signTree.cbeginLeaf(); leafIt; ++leafIt) {
761  for (auto it = leafIt->cbeginValueOn(); it; ++it) {
762  const int flags = int(it.getValue());
763  if (!(volume_to_mesh_internal::EDGES & flags)
764  && (volume_to_mesh_internal::INSIDE & flags))
765  {
766  instancePoints.push_back(transform.indexToWorld(it.getCoord()));
767  }
768  if (instancePoints.size() == size_t(instances)) break;
769  }
770  if (instancePoints.size() == size_t(instances)) break;
771  }
772  }
773
774  if (interrupter && interrupter->wasInterrupted()) return;
775
776  // Assign a radius to each candidate sphere. The radius is the world-space
777  // distance from the sphere's center to the closest surface point.
780
783  for (size_t n = 0, N = instancePoints.size(); n < N; ++n) {
787  }
788  }
789
791
794
795  for (size_t s = 0, S = std::min(size_t(maxSphereCount), instancePoints.size()); s < S; ++s) {
796
797  if (interrupter && interrupter->wasInterrupted()) return;
798
800
802
803  const Vec4s sphere(
808
809  spheres.push_back(sphere);
811
812  v2s_internal::UpdatePoints op(
814  op.run();
815
818  }
819 } // fillWithSpheres
820
821
822 ////////////////////////////////////////
823
824
825 template<typename GridT>
826 template<typename InterrupterT>
827 typename ClosestSurfacePoint<GridT>::Ptr
828 ClosestSurfacePoint<GridT>::create(const GridT& grid, float isovalue, InterrupterT* interrupter)
829 {
830  auto csp = Ptr{new ClosestSurfacePoint};
831  if (!csp->initialize(grid, isovalue, interrupter)) csp.reset();
832  return csp;
833 }
834
835
836 template<typename GridT>
837 template<typename InterrupterT>
838 bool
840  const GridT& grid, float isovalue, InterrupterT* interrupter)
841 {
842  using Index32LeafManagerT = tree::LeafManager<Index32TreeT>;
843  using ValueT = typename GridT::ValueType;
844
845  const TreeT& tree = grid.tree();
846  const math::Transform& transform = grid.transform();
847
848  { // Extract surface point cloud
849
852
853  mSignTreePt.reset(new Int16TreeT(0));
854  mIdxTreePt.reset(new Index32TreeT(std::numeric_limits<Index32>::max()));
855
856
857  volume_to_mesh_internal::computeAuxiliaryData(
858  *mSignTreePt, *mIdxTreePt, mask, tree, ValueT(isovalue));
859
860  if (interrupter && interrupter->wasInterrupted()) return false;
861
862  // count unique points
863
864  using Int16LeafNodeType = typename Int16TreeT::LeafNodeType;
865  using Index32LeafNodeType = typename Index32TreeT::LeafNodeType;
866
867  std::vector<Int16LeafNodeType*> signFlagsLeafNodes;
868  mSignTreePt->getNodes(signFlagsLeafNodes);
869
870  const tbb::blocked_range<size_t> auxiliaryLeafNodeRange(0, signFlagsLeafNodes.size());
871
872  std::unique_ptr<Index32[]> leafNodeOffsets(new Index32[signFlagsLeafNodes.size()]);
873
874  tbb::parallel_for(auxiliaryLeafNodeRange,
875  volume_to_mesh_internal::LeafNodePointCount<Int16LeafNodeType::LOG2DIM>
876  (signFlagsLeafNodes, leafNodeOffsets));
877
878  {
879  Index32 pointCount = 0;
880  for (size_t n = 0, N = signFlagsLeafNodes.size(); n < N; ++n) {
881  const Index32 tmp = leafNodeOffsets[n];
882  leafNodeOffsets[n] = pointCount;
883  pointCount += tmp;
884  }
885
886  mPointListSize = size_t(pointCount);
887  mSurfacePointList.reset(new Vec3s[mPointListSize]);
888  }
889
890
891  std::vector<Index32LeafNodeType*> pointIndexLeafNodes;
892  mIdxTreePt->getNodes(pointIndexLeafNodes);
893
894  tbb::parallel_for(auxiliaryLeafNodeRange, volume_to_mesh_internal::ComputePoints<TreeT>(
895  mSurfacePointList.get(), tree, pointIndexLeafNodes,
896  signFlagsLeafNodes, leafNodeOffsets, transform, ValueT(isovalue)));
897  }
898
899  if (interrupter && interrupter->wasInterrupted()) return false;
900
901  Index32LeafManagerT idxLeafs(*mIdxTreePt);
902
903  using Index32RootNodeT = typename Index32TreeT::RootNodeType;
904  using Index32NodeChainT = typename Index32RootNodeT::NodeChainType;
905  static_assert(Index32NodeChainT::Size > 1,
906  "expected tree depth greater than one");
907  using Index32InternalNodeT = typename Index32NodeChainT::template Get<1>;
908
909  typename Index32TreeT::NodeCIter nIt = mIdxTreePt->cbeginNode();
910  nIt.setMinDepth(Index32TreeT::NodeCIter::LEAF_DEPTH - 1);
911  nIt.setMaxDepth(Index32TreeT::NodeCIter::LEAF_DEPTH - 1);
912
913  std::vector<const Index32InternalNodeT*> internalNodes;
914
915  const Index32InternalNodeT* node = nullptr;
916  for (; nIt; ++nIt) {
917  nIt.getNode(node);
918  if (node) internalNodes.push_back(node);
919  }
920
921  std::vector<IndexRange>().swap(mLeafRanges);
922  mLeafRanges.resize(internalNodes.size());
923
924  std::vector<const Index32LeafT*>().swap(mLeafNodes);
925  mLeafNodes.reserve(idxLeafs.leafCount());
926
927  typename Index32InternalNodeT::ChildOnCIter leafIt;
928  mMaxNodeLeafs = 0;
929  for (size_t n = 0, N = internalNodes.size(); n < N; ++n) {
930
931  mLeafRanges[n].first = mLeafNodes.size();
932
933  size_t leafCount = 0;
934  for (leafIt = internalNodes[n]->cbeginChildOn(); leafIt; ++leafIt) {
935  mLeafNodes.push_back(&(*leafIt));
936  ++leafCount;
937  }
938
939  mMaxNodeLeafs = std::max(leafCount, mMaxNodeLeafs);
940
941  mLeafRanges[n].second = mLeafNodes.size();
942  }
943
944  std::vector<Vec4R>().swap(mLeafBoundingSpheres);
945  mLeafBoundingSpheres.resize(mLeafNodes.size());
946
947  v2s_internal::LeafOp<Index32LeafT> leafBS(
948  mLeafBoundingSpheres, mLeafNodes, transform, mSurfacePointList);
949  leafBS.run();
950
951
952  std::vector<Vec4R>().swap(mNodeBoundingSpheres);
953  mNodeBoundingSpheres.resize(internalNodes.size());
954
955  v2s_internal::NodeOp nodeBS(mNodeBoundingSpheres, mLeafRanges, mLeafBoundingSpheres);
956  nodeBS.run();
957  return true;
958 } // ClosestSurfacePoint::initialize
959
960
961 template<typename GridT>
962 bool
963 ClosestSurfacePoint<GridT>::search(std::vector<Vec3R>& points,
964  std::vector<float>& distances, bool transformPoints)
965 {
966  distances.clear();
967  distances.resize(points.size(), std::numeric_limits<float>::infinity());
968
969  v2s_internal::ClosestPointDist<Index32LeafT> cpd(points, distances, mSurfacePointList,
970  mLeafNodes, mLeafRanges, mLeafBoundingSpheres, mNodeBoundingSpheres,
971  mMaxNodeLeafs, transformPoints);
972
973  cpd.run();
974
975  return true;
976 }
977
978
979 template<typename GridT>
980 bool
981 ClosestSurfacePoint<GridT>::search(const std::vector<Vec3R>& points, std::vector<float>& distances)
982 {
983  return search(const_cast<std::vector<Vec3R>& >(points), distances, false);
984 }
985
986
987 template<typename GridT>
988 bool
990  std::vector<float>& distances)
991 {
992  return search(points, distances, true);
993 }
994
995
996 ////////////////////////////////////////
997
998
999 // Explicit Template Instantiation
1000
1001 #ifdef OPENVDB_USE_EXPLICIT_INSTANTIATION
1002
1003 #ifdef OPENVDB_INSTANTIATE_VOLUMETOSPHERES
1005 #endif
1006
1009
1010 #define _FUNCTION(TreeT) \
1011  void fillWithSpheres(const Grid<TreeT>&, std::vector<openvdb::Vec4s>&, const Vec2i&, \
1012  bool, float, float, float, int, util::NullInterrupter*)
1014 #undef _FUNCTION
1015
1016 #endif // OPENVDB_USE_EXPLICIT_INSTANTIATION
1017
1018
1019 } // namespace tools
1020 } // namespace OPENVDB_VERSION_NAME
1021 } // namespace openvdb
1022
1023 #endif // OPENVDB_TOOLS_VOLUME_TO_MESH_HAS_BEEN_INCLUDED
std::unique_ptr< openvdb::Vec3s[]> PointList
Point and primitive list types.
Definition: VolumeToMesh.h:160
bool searchAndReplace(std::vector< Vec3R > &points, std::vector< float > &distances)
Overwrite each input point with its closest surface point.
GLint first
Definition: glcorearb.h:405
void parallel_for(int64_t start, int64_t end, std::function< void(int64_t index)> &&task, parallel_options opt=parallel_options(0, Split_Y, 1))
Definition: parallel.h:127
typedef int(APIENTRYP RE_PFNGLXSWAPINTERVALSGIPROC)(int)
GA_API const UT_StringHolder dist
static Ptr create(const GridT &grid, float isovalue=0.0, InterrupterT *interrupter=nullptr)
Extract surface points and construct a spatial acceleration structure.
GLbitfield flags
Definition: glcorearb.h:1596
GLenum GLint * range
Definition: glcorearb.h:1925
GLdouble GLdouble GLint GLint const GLdouble * points
Vec3d indexToWorld(const Vec3d &xyz) const
Apply this transformation to the given coordinates.
Definition: Transform.h:108
math::Vec3< Real > Vec3R
Definition: Types.h:72
const TreeType & tree() const
Return a const reference to tree associated with this manager.
Definition: LeafManager.h:302
vfloat4 sqrt(const vfloat4 &a)
Definition: simd.h:7481
GLdouble GLdouble GLdouble z
Definition: glcorearb.h:848
#define OPENVDB_LOG_WARN(mesg)
Definition: logging.h:277
#define OPENVDB_REAL_TREE_INSTANTIATE(Function)
Definition: version.h:157
TreeType & tree()
Return a reference to this grid's tree, which might be shared with other grids.
Definition: Grid.h:908
GLdouble s
void swap(T &lhs, T &rhs)
Definition: pugixml.cpp:7172
#define OPENVDB_USE_VERSION_NAMESPACE
Definition: version.h:239
void erodeActiveValues(TreeOrLeafManagerT &tree, const int iterations=1, const NearestNeighbors nn=NN_FACE, const TilePolicy mode=PRESERVE_TILES, const bool threaded=true)
Topologically erode all active values (i.e. both voxels and tiles) in a tree using one of three neare...
Definition: Morphology.h:1133
ImageBuf OIIO_API min(Image_or_Const A, Image_or_Const B, ROI roi={}, int nthreads=0)
GLint y
Definition: glcorearb.h:103
Tolerance for floating-point comparison.
Definition: Math.h:148
float Cbrt(float x)
Return the cube root of a floating-point value.
Definition: Math.h:769
typename TreeT::template ValueConverter< bool >::Type BoolTreeT
Accelerated closest surface point queries for narrow band level sets.
bool search(const std::vector< Vec3R > &points, std::vector< float > &distances)
Compute the distance from each input point to its closest surface point.
GA_API const UT_StringHolder scale
GLdouble n
Definition: glcorearb.h:2008
GLfloat f
Definition: glcorearb.h:1926
Vec3d voxelSize() const
Return the size of a voxel using the linear component of the map.
Definition: Transform.h:93
#define OPENVDB_INSTANTIATE_CLASS
exint length() const
The two point scatters UniformPointScatter and NonUniformPointScatter depend on the following two cla...
Definition: PointScatter.h:87
Extract polygonal surfaces from scalar volumes.
typename TreeT::template ValueConverter< Index32 >::Type Index32TreeT
We offer three different algorithms (each in its own class) for scattering of points in active voxels...
General-purpose arithmetic and comparison routines, most of which accept arbitrary value types (or at...
Definition: glcorearb.h:124
This class manages a linear array of pointers to a given tree's leaf nodes, as well as optional auxil...
Definition: LeafManager.h:84
Index64 pointCount(const PointDataTreeT &tree, const FilterT &filter, const bool inCoreOnly, const bool threaded)
Count the total number of points in a PointDataTree.
OPENVDB_API void initialize()
Global registration of native Grid, Transform, Metadata and Point attribute types. Also initializes blosc (if enabled).
Definition: logging.h:294
GA_API const UT_StringHolder transform
GLint GLenum GLint x
Definition: glcorearb.h:409
Miscellaneous utility methods that operate primarily or exclusively on level set grids.
Container class that associates a tree with a transform and metadata.
Definition: Grid.h:28
math::Vec4< Real > Vec4R
Definition: Types.h:87
auto search(const T &set, const V &val) -> std::pair< bool, decltype(std::begin(detail::smart_deref(set)))>
A search function.
Definition: CLI11.h:3170
Type Clamp(Type x, Type min, Type max)
Return x clamped to [min, max].
Definition: Math.h:261
GridType::Ptr levelSetRebuild(const GridType &grid, float isovalue=0, float halfWidth=float(LEVEL_SET_HALF_WIDTH), const math::Transform *xform=nullptr)
Return a new grid of type GridType that contains a narrow-band level set representation of an isosurf...
GLsizeiptr size
Definition: glcorearb.h:664
const Index32TreeT & indexTree() const
Tree accessor.
#define OPENVDB_LOG_DEBUG_RUNTIME(mesg)
Definition: logging.h:281
const Int16TreeT & signTree() const
Tree accessor.
GLuint index
Definition: glcorearb.h:786
ImageBuf OIIO_API max(Image_or_Const A, Image_or_Const B, ROI roi={}, int nthreads=0)
GA_API const UT_StringHolder N
Implementation of morphological dilation and erosion.
GridOrTreeType::template ValueConverter< bool >::Type::Ptr sdfInteriorMask(const GridOrTreeType &volume, typename GridOrTreeType::ValueType isovalue=lsutilGridZero< GridOrTreeType >())
Threaded method to construct a boolean mask that represents interior regions in a signed distance fie...
typename TreeT::template ValueConverter< Int16 >::Type Int16TreeT
A LeafManager manages a linear array of pointers to a given tree's leaf nodes, as well as optional au...
void OIIO_UTIL_API split(string_view str, std::vector< string_view > &result, string_view sep=string_view(), int maxsplit=-1)
void setTransform(math::Transform::Ptr)
Associate the given transform with this grid, in place of its existing transform. ...
Definition: Grid.h:1234
#define OPENVDB_VERSION_NAME
The version namespace name for this library version.
Definition: version.h:119
void fillWithSpheres(const GridT &grid, std::vector< openvdb::Vec4s > &spheres, const Vec2i &sphereCount=Vec2i(1, 50), bool overlapping=false, float minRadius=1.0, float maxRadius=std::numeric_limits< float >::max(), float isovalue=0.0, int instanceCount=10000, InterrupterT *interrupter=nullptr)
Fill a closed level set or fog volume with adaptively-sized spheres.
GLint GLsizei count
Definition: glcorearb.h:405
void pruneInactive(TreeT &tree, bool threaded=true, size_t grainSize=1)
Reduce the memory footprint of a tree by replacing with background tiles any nodes whose values are a...
Definition: Prune.h:355
auto join(It begin, Sentinel end, string_view sep) -> join_view< It, Sentinel >
Definition: format.h:2559
void setTree(TreeBase::Ptr) override
Associate the given tree with this grid, in place of its existing tree.
Definition: Grid.h:1454