OpenVDB: openvdb/tools/PointScatter.h Source File

OpenVDB 13.0.0

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PointScatter.h
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1// Copyright Contributors to the OpenVDB Project
2// SPDX-License-Identifier: Apache-2.0
3//
4/// @author Ken Museth
5///
6/// @file tools/PointScatter.h
7///
8/// @brief We offer three different algorithms (each in its own class)
9/// for scattering of points in active voxels:
10///
11/// 1) UniformPointScatter. Has two modes: Either randomly distributes
12/// a fixed number of points into the active voxels, or the user can
13/// specify a fixed probability of having a points per unit of volume.
14///
15/// 2) DenseUniformPointScatter. Randomly distributes points into active
16/// voxels using a fixed number of points per voxel.
17///
18/// 3) NonIniformPointScatter. Define the local probability of having
19/// a point in a voxel as the product of a global density and the
20/// value of the voxel itself.
21
22#ifndef OPENVDB_TOOLS_POINT_SCATTER_HAS_BEEN_INCLUDED
23#define OPENVDB_TOOLS_POINT_SCATTER_HAS_BEEN_INCLUDED
24
25#include <openvdb/Types.h>
26#include <openvdb/Grid.h>
27#include <openvdb/math/Math.h>
28#include <openvdb/util/NullInterrupter.h>
29#include <tbb/parallel_sort.h>
30#include <tbb/parallel_for.h>
31#include <iostream>
32#include <memory>
33#include <string>
34
35namespace openvdb {
36 OPENVDB_USE_VERSION_NAMESPACE
37namespace OPENVDB_VERSION_NAME {
38namespace tools {
39
40/// Forward declaration of base class
41template<typename PointAccessorType,
42 typename RandomGenerator,
43 typename InterruptType = util::NullInterrupter>
44class BasePointScatter;
45
46/// @brief The two point scatters UniformPointScatter and
47/// NonUniformPointScatter depend on the following two classes:
48///
49/// The @c PointAccessorType template argument below refers to any class
50/// with the following interface:
51/// @code
52/// class PointAccessor {
53/// ...
54/// public:
55/// void add(const openvdb::Vec3R &pos);// appends point with world positions pos
56/// };
57/// @endcode
58///
59///
60/// The @c InterruptType template argument below refers to any class
61/// with the following interface:
62/// @code
63/// class Interrupter {
64/// ...
65/// public:
66/// void start(const char* name = nullptr) // called when computations begin
67/// void end() // called when computations end
68/// bool wasInterrupted(int percent=-1) // return true to break computation
69///};
70/// @endcode
71///
72/// @note If no template argument is provided for this InterruptType
73/// the util::NullInterrupter is used which implies that all
74/// interrupter calls are no-ops (i.e. incurs no computational overhead).
75
76
77/// @brief Uniformly scatters points in the active voxels.
78/// The point count is either explicitly defined or implicitly
79/// through the specification of a global density (=points-per-volume)
80///
81/// @note This uniform scattering technique assumes that the number of
82/// points is generally smaller than the number of active voxels
83/// (including virtual active voxels in active tiles).
84template<typename PointAccessorType,
85 typename RandomGenerator,
86 typename InterruptType = util::NullInterrupter>
87 class UniformPointScatter : public BasePointScatter<PointAccessorType,
88 RandomGenerator,
89 InterruptType>
90{
91public:
92 using BaseT = BasePointScatter<PointAccessorType, RandomGenerator, InterruptType>;
93
94 UniformPointScatter(PointAccessorType& points,
95 Index64 pointCount,
96 RandomGenerator& randGen,
97 double spread = 1.0,
98 InterruptType* interrupt = nullptr)
99 : BaseT(points, randGen, spread, interrupt)
100 , mTargetPointCount(pointCount)
101 , mPointsPerVolume(0.0f)
102 {
103 }
104 UniformPointScatter(PointAccessorType& points,
105 float pointsPerVolume,
106 RandomGenerator& randGen,
107 double spread = 1.0,
108 InterruptType* interrupt = nullptr)
109 : BaseT(points, randGen, spread, interrupt)
110 , mTargetPointCount(0)
111 , mPointsPerVolume(pointsPerVolume)
112 {
113 }
114
115 /// This is the main functor method implementing the actual scattering of points.
116 template<typename GridT>
117 bool operator()(const GridT& grid)
118 {
119 mVoxelCount = grid.activeVoxelCount();
120 if (mVoxelCount == 0) return false;
121
122 const auto voxelVolume = grid.transform().voxelVolume();
123 if (mPointsPerVolume > 0) {
124 BaseT::start("Uniform scattering with fixed point density");
125 mTargetPointCount = Index64(mPointsPerVolume * voxelVolume * double(mVoxelCount));
126 } else if (mTargetPointCount > 0) {
127 BaseT::start("Uniform scattering with fixed point count");
128 mPointsPerVolume = float(mTargetPointCount) / float(voxelVolume * double(mVoxelCount));
129 } else {
130 return false;
131 }
132
133 std::unique_ptr<Index64[]> idList{new Index64[mTargetPointCount]};
134 math::RandInt<Index64, RandomGenerator> rand(BaseT::mRand01.engine(), 0, mVoxelCount-1);
135 for (Index64 i=0; i<mTargetPointCount; ++i) idList[i] = rand();
136 tbb::parallel_sort(idList.get(), idList.get() + mTargetPointCount);
137
138 CoordBBox bbox;
139 const Vec3R offset(0.5, 0.5, 0.5);
140 typename GridT::ValueOnCIter valueIter = grid.cbeginValueOn();
141
142 for (Index64 i=0, n=valueIter.getVoxelCount() ; i != mTargetPointCount; ++i) {
143 if (BaseT::interrupt()) return false;
144 const Index64 voxelId = idList[i];
145 while ( n <= voxelId ) {
146 ++valueIter;
147 n += valueIter.getVoxelCount();
148 }
149 if (valueIter.isVoxelValue()) {// a majority is expected to be voxels
150 BaseT::addPoint(grid, valueIter.getCoord() - offset);
151 } else {// tiles contain multiple (virtual) voxels
152 valueIter.getBoundingBox(bbox);
153 BaseT::addPoint(grid, bbox.min() - offset, bbox.extents());
154 }
155 }//loop over all the active voxels and tiles
156 //}
157
158 BaseT::end();
159 return true;
160 }
161
162 // The following methods should only be called after the
163 // the operator() method was called
164 void print(const std::string &name, std::ostream& os = std::cout) const
165 {
166 os << "Uniformly scattered " << mPointCount << " points into " << mVoxelCount
167 << " active voxels in \"" << name << "\" corresponding to "
168 << mPointsPerVolume << " points per volume." << std::endl;
169 }
170
171 float getPointsPerVolume() const { return mPointsPerVolume; }
172 Index64 getTargetPointCount() const { return mTargetPointCount; }
173
174private:
175
176 using BaseT::mPointCount;
177 using BaseT::mVoxelCount;
178 Index64 mTargetPointCount;
179 float mPointsPerVolume;
180
181}; // class UniformPointScatter
182
183/// @brief Scatters a fixed (and integer) number of points in all
184/// active voxels and tiles.
185template<typename PointAccessorType,
186 typename RandomGenerator,
187 typename InterruptType = util::NullInterrupter>
188 class DenseUniformPointScatter : public BasePointScatter<PointAccessorType,
189 RandomGenerator,
190 InterruptType>
191{
192public:
193 using BaseT = BasePointScatter<PointAccessorType, RandomGenerator, InterruptType>;
194
195 DenseUniformPointScatter(PointAccessorType& points,
196 float pointsPerVoxel,
197 RandomGenerator& randGen,
198 double spread = 1.0,
199 InterruptType* interrupt = nullptr)
200 : BaseT(points, randGen, spread, interrupt)
201 , mPointsPerVoxel(pointsPerVoxel)
202 {
203 }
204
205 /// This is the main functor method implementing the actual scattering of points.
206 template<typename GridT>
207 bool operator()(const GridT& grid)
208 {
209 using ValueIter = typename GridT::ValueOnCIter;
210 if (mPointsPerVoxel < 1.0e-6) return false;
211 mVoxelCount = grid.activeVoxelCount();
212 if (mVoxelCount == 0) return false;
213 BaseT::start("Dense uniform scattering with fixed point count");
214 CoordBBox bbox;
215 const Vec3R offset(0.5, 0.5, 0.5);
216
217 const int ppv = math::Floor(mPointsPerVoxel);
218 const double delta = mPointsPerVoxel - float(ppv);
219 const bool fractional = !math::isApproxZero(delta, 1.0e-6);
220
221 for (ValueIter iter = grid.cbeginValueOn(); iter; ++iter) {
222 if (BaseT::interrupt()) return false;
223 if (iter.isVoxelValue()) {// a majority is expected to be voxels
224 const Vec3R dmin = iter.getCoord() - offset;
225 for (int n = 0; n != ppv; ++n) BaseT::addPoint(grid, dmin);
226 if (fractional && BaseT::getRand01() < delta) BaseT::addPoint(grid, dmin);
227 } else {// tiles contain multiple (virtual) voxels
228 iter.getBoundingBox(bbox);
229 const Coord size(bbox.extents());
230 const Vec3R dmin = bbox.min() - offset;
231 const double d = mPointsPerVoxel * float(iter.getVoxelCount());
232 const int m = math::Floor(d);
233 for (int n = 0; n != m; ++n) BaseT::addPoint(grid, dmin, size);
234 if (BaseT::getRand01() < d - m) BaseT::addPoint(grid, dmin, size);
235 }
236 }//loop over all the active voxels and tiles
237 //}
238 BaseT::end();
239 return true;
240 }
241
242 // The following methods should only be called after the
243 // the operator() method was called
244 void print(const std::string &name, std::ostream& os = std::cout) const
245 {
246 os << "Dense uniformly scattered " << mPointCount << " points into " << mVoxelCount
247 << " active voxels in \"" << name << "\" corresponding to "
248 << mPointsPerVoxel << " points per voxel." << std::endl;
249 }
250
251 float getPointsPerVoxel() const { return mPointsPerVoxel; }
252
253private:
254 using BaseT::mPointCount;
255 using BaseT::mVoxelCount;
256 float mPointsPerVoxel;
257}; // class DenseUniformPointScatter
258
259/// @brief Non-uniform scatters of point in the active voxels.
260/// The local point count is implicitly defined as a product of
261/// of a global density (called pointsPerVolume) and the local voxel
262/// (or tile) value.
263///
264/// @note This scattering technique can be significantly slower
265/// than a uniform scattering since its computational complexity
266/// is proportional to the active voxel (and tile) count.
267template<typename PointAccessorType,
268 typename RandomGenerator,
269 typename InterruptType = util::NullInterrupter>
270 class NonUniformPointScatter : public BasePointScatter<PointAccessorType,
271 RandomGenerator,
272 InterruptType>
273{
274public:
275 using BaseT = BasePointScatter<PointAccessorType, RandomGenerator, InterruptType>;
276
277 NonUniformPointScatter(PointAccessorType& points,
278 float pointsPerVolume,
279 RandomGenerator& randGen,
280 double spread = 1.0,
281 InterruptType* interrupt = nullptr)
282 : BaseT(points, randGen, spread, interrupt)
283 , mPointsPerVolume(pointsPerVolume)//note this is merely a
284 //multiplier for the local point density
285 {
286 }
287
288 /// This is the main functor method implementing the actual scattering of points.
289 template<typename GridT>
290 bool operator()(const GridT& grid)
291 {
292 if (mPointsPerVolume <= 0.0f) return false;
293 mVoxelCount = grid.activeVoxelCount();
294 if (mVoxelCount == 0) return false;
295 BaseT::start("Non-uniform scattering with local point density");
296 const Vec3d dim = grid.voxelSize();
297 const double volumePerVoxel = dim[0]*dim[1]*dim[2],
298 pointsPerVoxel = mPointsPerVolume * volumePerVoxel;
299 CoordBBox bbox;
300 const Vec3R offset(0.5, 0.5, 0.5);
301 for (typename GridT::ValueOnCIter iter = grid.cbeginValueOn(); iter; ++iter) {
302 if (BaseT::interrupt()) return false;
303 const double d = double(*iter) * pointsPerVoxel * double(iter.getVoxelCount());
304 const int n = int(d);
305 if (iter.isVoxelValue()) { // a majority is expected to be voxels
306 const Vec3R dmin =iter.getCoord() - offset;
307 for (int i = 0; i < n; ++i) BaseT::addPoint(grid, dmin);
308 if (BaseT::getRand01() < (d - n)) BaseT::addPoint(grid, dmin);
309 } else { // tiles contain multiple (virtual) voxels
310 iter.getBoundingBox(bbox);
311 const Coord size(bbox.extents());
312 const Vec3R dmin = bbox.min() - offset;
313 for (int i = 0; i < n; ++i) BaseT::addPoint(grid, dmin, size);
314 if (BaseT::getRand01() < (d - n)) BaseT::addPoint(grid, dmin, size);
315 }
316 }//loop over all the active voxels and tiles
317 BaseT::end();
318 return true;
319 }
320
321 // The following methods should only be called after the
322 // the operator() method was called
323 void print(const std::string &name, std::ostream& os = std::cout) const
324 {
325 os << "Non-uniformly scattered " << mPointCount << " points into " << mVoxelCount
326 << " active voxels in \"" << name << "\"." << std::endl;
327 }
328
329 float getPointPerVolume() const { return mPointsPerVolume; }
330
331private:
332 using BaseT::mPointCount;
333 using BaseT::mVoxelCount;
334 float mPointsPerVolume;
335
336}; // class NonUniformPointScatter
337
338/// Base class of all the point scattering classes defined above
339template<typename PointAccessorType,
340 typename RandomGenerator,
341 typename InterruptType>
342 class BasePointScatter
343{
344public:
345
346 Index64 getPointCount() const { return mPointCount; }
347 Index64 getVoxelCount() const { return mVoxelCount; }
348
349protected:
350
351 PointAccessorType& mPoints;
352 InterruptType* mInterrupter;
353 Index64 mPointCount;
354 Index64 mVoxelCount;
355 Index64 mInterruptCount;
356 const double mSpread;
357 math::Rand01<double, RandomGenerator> mRand01;
358
359 /// This is a base class so the constructor is protected
360 BasePointScatter(PointAccessorType& points,
361 RandomGenerator& randGen,
362 double spread,
363 InterruptType* interrupt = nullptr)
364 : mPoints(points)
365 , mInterrupter(interrupt)
366 , mPointCount(0)
367 , mVoxelCount(0)
368 , mInterruptCount(0)
369 , mSpread(math::Clamp01(spread))
370 , mRand01(randGen)
371 {
372 }
373
374 inline void start(const char* name)
375 {
376 if (mInterrupter) mInterrupter->start(name);
377 }
378
379 inline void end()
380 {
381 if (mInterrupter) mInterrupter->end();
382 }
383
384 inline bool interrupt()
385 {
386 //only check interrupter for every 32'th call
387 return !(mInterruptCount++ & ((1<<5)-1)) && util::wasInterrupted(mInterrupter);
388 }
389
390 /// @brief Return a random floating point number between zero and one
391 inline double getRand01() { return mRand01(); }
392
393 /// @brief Return a random floating point number between 0.5 -+ mSpread/2
394 inline double getRand() { return 0.5 + mSpread * (mRand01() - 0.5); }
395
396 template <typename GridT>
397 inline void addPoint(const GridT &grid, const Vec3R &dmin)
398 {
399 const Vec3R pos(dmin[0] + this->getRand(),
400 dmin[1] + this->getRand(),
401 dmin[2] + this->getRand());
402 mPoints.add(grid.indexToWorld(pos));
403 ++mPointCount;
404 }
405
406 template <typename GridT>
407 inline void addPoint(const GridT &grid, const Vec3R &dmin, const Coord &size)
408 {
409 const Vec3R pos(dmin[0] + size[0]*this->getRand(),
410 dmin[1] + size[1]*this->getRand(),
411 dmin[2] + size[2]*this->getRand());
412 mPoints.add(grid.indexToWorld(pos));
413 ++mPointCount;
414 }
415};// class BasePointScatter
416
417} // namespace tools
418} // namespace OPENVDB_VERSION_NAME
419} // namespace openvdb
420
421#endif // OPENVDB_TOOLS_POINT_SCATTER_HAS_BEEN_INCLUDED
Grid.h
Math.h
General-purpose arithmetic and comparison routines, most of which accept arbitrary value types (or at...
NullInterrupter.h
openvdb::v13_0::math::CoordBBox
Axis-aligned bounding box of signed integer coordinates.
Definition Coord.h:252
openvdb::v13_0::math::CoordBBox::extents
Coord extents() const
Definition Coord.h:385
openvdb::v13_0::math::CoordBBox::min
const Coord & min() const
Definition Coord.h:324
openvdb::v13_0::math::Coord
Signed (x, y, z) 32-bit integer coordinates.
Definition Coord.h:26
openvdb::v13_0::math::Rand01
Simple generator of random numbers over the range [0, 1).
Definition Math.h:180
openvdb::v13_0::math::RandInt
Simple random integer generator.
Definition Math.h:216
openvdb::v13_0::tools::BasePointScatter::addPoint
void addPoint(const GridT &grid, const Vec3R &dmin)
Definition PointScatter.h:397
openvdb::v13_0::tools::BasePointScatter::addPoint
void addPoint(const GridT &grid, const Vec3R &dmin, const Coord &size)
Definition PointScatter.h:407
openvdb::v13_0::tools::BasePointScatter::mInterrupter
InterruptType * mInterrupter
Definition PointScatter.h:352
openvdb::v13_0::tools::BasePointScatter::mInterruptCount
Index64 mInterruptCount
Definition PointScatter.h:355
openvdb::v13_0::tools::BasePointScatter::start
void start(const char *name)
Definition PointScatter.h:374
openvdb::v13_0::tools::BasePointScatter::mSpread
const double mSpread
Definition PointScatter.h:356
openvdb::v13_0::tools::BasePointScatter::getPointCount
Index64 getPointCount() const
Definition PointScatter.h:346
openvdb::v13_0::tools::BasePointScatter::mPoints
PointAccessorType & mPoints
Definition PointScatter.h:351
openvdb::v13_0::tools::BasePointScatter< PointAccessorType, RandomGenerator, util::NullInterrupter >::BasePointScatter
BasePointScatter(PointAccessorType &points, RandomGenerator &randGen, double spread, util::NullInterrupter *interrupt=nullptr)
Definition PointScatter.h:360
openvdb::v13_0::tools::BasePointScatter::mVoxelCount
Index64 mVoxelCount
Definition PointScatter.h:354
openvdb::v13_0::tools::BasePointScatter::mRand01
math::Rand01< double, RandomGenerator > mRand01
Definition PointScatter.h:357
openvdb::v13_0::tools::BasePointScatter::getVoxelCount
Index64 getVoxelCount() const
Definition PointScatter.h:347
openvdb::v13_0::tools::BasePointScatter::end
void end()
Definition PointScatter.h:379
openvdb::v13_0::tools::BasePointScatter::getRand01
double getRand01()
Return a random floating point number between zero and one.
Definition PointScatter.h:391
openvdb::v13_0::tools::BasePointScatter::mPointCount
Index64 mPointCount
Definition PointScatter.h:353
openvdb::v13_0::tools::BasePointScatter::getRand
double getRand()
Return a random floating point number between 0.5 -+ mSpread/2.
Definition PointScatter.h:394
openvdb::v13_0::tools::BasePointScatter< PointAccessorType, RandomGenerator, util::NullInterrupter >::interrupt
bool interrupt()
Definition PointScatter.h:384
openvdb::v13_0::tools::DenseUniformPointScatter::print
void print(const std::string &name, std::ostream &os=std::cout) const
Definition PointScatter.h:244
openvdb::v13_0::tools::DenseUniformPointScatter::BaseT
BasePointScatter< PointAccessorType, RandomGenerator, InterruptType > BaseT
Definition PointScatter.h:193
openvdb::v13_0::tools::DenseUniformPointScatter::getPointsPerVoxel
float getPointsPerVoxel() const
Definition PointScatter.h:251
openvdb::v13_0::tools::DenseUniformPointScatter::operator()
bool operator()(const GridT &grid)
This is the main functor method implementing the actual scattering of points.
Definition PointScatter.h:207
openvdb::v13_0::tools::DenseUniformPointScatter::DenseUniformPointScatter
DenseUniformPointScatter(PointAccessorType &points, float pointsPerVoxel, RandomGenerator &randGen, double spread=1.0, InterruptType *interrupt=nullptr)
Definition PointScatter.h:195
openvdb::v13_0::tools::NonUniformPointScatter::getPointPerVolume
float getPointPerVolume() const
Definition PointScatter.h:329
openvdb::v13_0::tools::NonUniformPointScatter::print
void print(const std::string &name, std::ostream &os=std::cout) const
Definition PointScatter.h:323
openvdb::v13_0::tools::NonUniformPointScatter::BaseT
BasePointScatter< PointAccessorType, RandomGenerator, InterruptType > BaseT
Definition PointScatter.h:275
openvdb::v13_0::tools::NonUniformPointScatter::operator()
bool operator()(const GridT &grid)
This is the main functor method implementing the actual scattering of points.
Definition PointScatter.h:290
openvdb::v13_0::tools::NonUniformPointScatter::NonUniformPointScatter
NonUniformPointScatter(PointAccessorType &points, float pointsPerVolume, RandomGenerator &randGen, double spread=1.0, InterruptType *interrupt=nullptr)
Definition PointScatter.h:277
openvdb::v13_0::tools::UniformPointScatter::print
void print(const std::string &name, std::ostream &os=std::cout) const
Definition PointScatter.h:164
openvdb::v13_0::tools::UniformPointScatter::getTargetPointCount
Index64 getTargetPointCount() const
Definition PointScatter.h:172
openvdb::v13_0::tools::UniformPointScatter::UniformPointScatter
UniformPointScatter(PointAccessorType &points, Index64 pointCount, RandomGenerator &randGen, double spread=1.0, InterruptType *interrupt=nullptr)
Definition PointScatter.h:94
openvdb::v13_0::tools::UniformPointScatter::UniformPointScatter
UniformPointScatter(PointAccessorType &points, float pointsPerVolume, RandomGenerator &randGen, double spread=1.0, InterruptType *interrupt=nullptr)
Definition PointScatter.h:104
openvdb::v13_0::tools::UniformPointScatter::BaseT
BasePointScatter< PointAccessorType, RandomGenerator, InterruptType > BaseT
Definition PointScatter.h:92
openvdb::v13_0::tools::UniformPointScatter::operator()
bool operator()(const GridT &grid)
This is the main functor method implementing the actual scattering of points.
Definition PointScatter.h:117
openvdb::v13_0::tools::UniformPointScatter::getPointsPerVolume
float getPointsPerVolume() const
Definition PointScatter.h:171
openvdb::v13_0::math
Definition Types.h:759
openvdb::v13_0::math::isApproxZero
bool isApproxZero(const Type &x)
Return true if x is equal to zero to within the default floating-point comparison tolerance.
Definition Math.h:362
openvdb::v13_0::math::Vec3d
Vec3< double > Vec3d
Definition Vec3.h:665
openvdb::v13_0::math::Floor
int Floor(float x)
Return the floor of x.
Definition Math.h:919
openvdb::v13_0::points
Definition AttributeArray.h:42
openvdb::v13_0::util::wasInterrupted
bool wasInterrupted(T *i, int percent=-1)
Definition NullInterrupter.h:49
openvdb::v13_0::Vec3R
math::Vec3< Real > Vec3R
Definition Types.h:53
openvdb::v13_0::Index64
uint64_t Index64
Definition Types.h:33
openvdb
Definition Exceptions.h:13
Types.h
openvdb::v13_0::util::NullInterrupter
Base class for interrupters.
Definition NullInterrupter.h:26
OPENVDB_VERSION_NAME
#define OPENVDB_VERSION_NAME
The version namespace name for this library version.
Definition version.h.in:121
OPENVDB_USE_VERSION_NAMESPACE
#define OPENVDB_USE_VERSION_NAMESPACE
Definition version.h.in:218