OpenVDB: openvdb/tools/RayIntersector.h Source File

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RayIntersector.h
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1// Copyright Contributors to the OpenVDB Project
2// SPDX-License-Identifier: Apache-2.0
3///
4/// @file RayIntersector.h
5///
6/// @author Ken Museth
7///
8/// @brief Accelerated intersection of a ray with a narrow-band level
9/// set or a generic (e.g. density) volume. This will of course be
10/// useful for respectively surface and volume rendering.
11///
12/// @details This file defines two main classes,
13/// LevelSetRayIntersector and VolumeRayIntersector, as well as the
14/// three support classes LevelSetHDDA, VolumeHDDA and LinearSearchImpl.
15/// The LevelSetRayIntersector is templated on the LinearSearchImpl class
16/// and calls instances of the LevelSetHDDA class. The reason to split
17/// level set ray intersection into three classes is twofold. First
18/// LevelSetRayIntersector defines the public API for client code and
19/// LinearSearchImpl defines the actual algorithm used for the
20/// ray level-set intersection. In other words this design will allow
21/// for the public API to be fixed while the intersection algorithm
22/// can change without resolving to (slow) virtual methods. Second,
23/// LevelSetHDDA, which implements a hierarchical Differential Digital
24/// Analyzer, relies on partial template specialization, so it has to
25/// be a standalone class (as opposed to a member class of
26/// LevelSetRayIntersector). The VolumeRayIntersector is conceptually
27/// much simpler than the LevelSetRayIntersector, and hence it only
28/// depends on VolumeHDDA that implements the hierarchical
29/// Differential Digital Analyzer.
30
31
32#ifndef OPENVDB_TOOLS_RAYINTERSECTOR_HAS_BEEN_INCLUDED
33#define OPENVDB_TOOLS_RAYINTERSECTOR_HAS_BEEN_INCLUDED
34
35#include <openvdb/math/DDA.h>
36#include <openvdb/math/Math.h>
37#include <openvdb/math/Ray.h>
38#include <openvdb/math/Stencils.h>
39#include <openvdb/Grid.h>
40#include <openvdb/Types.h>
41#include <openvdb/util/Assert.h>
42#include "Morphology.h"
43#include <iostream>
44#include <type_traits>
45
46
47namespace openvdb {
48 OPENVDB_USE_VERSION_NAMESPACE
49namespace OPENVDB_VERSION_NAME {
50namespace tools {
51
52// Helper class that implements the actual search of the zero-crossing
53// of the level set along the direction of a ray. This particular
54// implementation uses iterative linear search.
55template<typename GridT, int Iterations = 0, typename RealT = double>
56class LinearSearchImpl;
57
58
59///////////////////////////////////// LevelSetRayIntersector /////////////////////////////////////
60
61
62/// @brief This class provides the public API for intersecting a ray
63/// with a narrow-band level set.
64///
65/// @details It wraps a SearchImplT with a simple public API and
66/// performs the actual hierarchical tree node and voxel traversal.
67///
68/// @warning Use the (default) copy-constructor to make sure each
69/// computational thread has their own instance of this class. This is
70/// important since the SearchImplT contains a ValueAccessor that is
71/// not thread-safe. However copying is very efficient.
72///
73/// @see tools/RayTracer.h for examples of intended usage.
74///
75/// @todo Add TrilinearSearchImpl, as an alternative to LinearSearchImpl,
76/// that performs analytical 3D trilinear intersection tests, i.e., solves
77/// cubic equations. This is slower but also more accurate than the 1D
78/// linear interpolation in LinearSearchImpl.
79template<typename GridT,
80 typename SearchImplT = LinearSearchImpl<GridT>,
81 int NodeLevel = GridT::TreeType::RootNodeType::ChildNodeType::LEVEL,
82 typename RayT = math::Ray<Real> >
83 class LevelSetRayIntersector
84{
85public:
86 using GridType = GridT;
87 using RayType = RayT;
88 using RealType = typename RayT::RealType;
89 using Vec3Type = typename RayT::Vec3T;
90 using ValueT = typename GridT::ValueType;
91 using TreeT = typename GridT::TreeType;
92
93 static_assert(NodeLevel >= -1 && NodeLevel < int(TreeT::DEPTH)-1, "NodeLevel out of range");
94 static_assert(std::is_floating_point<ValueT>::value,
95 "level set grids must have scalar, floating-point value types");
96
97 /// @brief Constructor
98 /// @param grid level set grid to intersect rays against.
99 /// @param isoValue optional iso-value for the ray-intersection.
100 LevelSetRayIntersector(const GridT& grid, const ValueT& isoValue = zeroVal<ValueT>())
101 : mTester(grid, isoValue)
102 {
103 if (!grid.hasUniformVoxels() ) {
104 OPENVDB_THROW(RuntimeError,
105 "LevelSetRayIntersector only supports uniform voxels!");
106 }
107 if (grid.getGridClass() != GRID_LEVEL_SET) {
108 OPENVDB_THROW(RuntimeError,
109 "LevelSetRayIntersector only supports level sets!"
110 "\nUse Grid::setGridClass(openvdb::GRID_LEVEL_SET)");
111 }
112 }
113
114 /// @brief Return the iso-value used for ray-intersections
115 const ValueT& getIsoValue() const { return mTester.getIsoValue(); }
116
117 /// @brief Return @c true if the index-space ray intersects the level set.
118 /// @param iRay ray represented in index space.
119 bool intersectsIS(const RayType& iRay) const
120 {
121 if (!mTester.setIndexRay(iRay)) return false;//missed bbox
122 return math::LevelSetHDDA<TreeT, NodeLevel>::test(mTester);
123 }
124
125 /// @brief Return @c true if the index-space ray intersects the level set
126 /// @param iRay ray represented in index space.
127 /// @param iTime if an intersection was found it is assigned the time of the
128 /// intersection along the index ray.
129 bool intersectsIS(const RayType& iRay, RealType &iTime) const
130 {
131 if (!mTester.setIndexRay(iRay)) return false;//missed bbox
132 iTime = mTester.getIndexTime();
133 return math::LevelSetHDDA<TreeT, NodeLevel>::test(mTester);
134 }
135
136 /// @brief Return @c true if the index-space ray intersects the level set.
137 /// @param iRay ray represented in index space.
138 /// @param xyz if an intersection was found it is assigned the
139 /// intersection point in index space, otherwise it is unchanged.
140 bool intersectsIS(const RayType& iRay, Vec3Type& xyz) const
141 {
142 if (!mTester.setIndexRay(iRay)) return false;//missed bbox
143 if (!math::LevelSetHDDA<TreeT, NodeLevel>::test(mTester)) return false;//missed level set
144 mTester.getIndexPos(xyz);
145 return true;
146 }
147
148 /// @brief Return @c true if the index-space ray intersects the level set.
149 /// @param iRay ray represented in index space.
150 /// @param xyz if an intersection was found it is assigned the
151 /// intersection point in index space, otherwise it is unchanged.
152 /// @param iTime if an intersection was found it is assigned the time of the
153 /// intersection along the index ray.
154 bool intersectsIS(const RayType& iRay, Vec3Type& xyz, RealType &iTime) const
155 {
156 if (!mTester.setIndexRay(iRay)) return false;//missed bbox
157 if (!math::LevelSetHDDA<TreeT, NodeLevel>::test(mTester)) return false;//missed level set
158 mTester.getIndexPos(xyz);
159 iTime = mTester.getIndexTime();
160 return true;
161 }
162
163 /// @brief Return @c true if the world-space ray intersects the level set.
164 /// @param wRay ray represented in world space.
165 bool intersectsWS(const RayType& wRay) const
166 {
167 if (!mTester.setWorldRay(wRay)) return false;//missed bbox
168 return math::LevelSetHDDA<TreeT, NodeLevel>::test(mTester);
169 }
170
171 /// @brief Return @c true if the world-space ray intersects the level set.
172 /// @param wRay ray represented in world space.
173 /// @param wTime if an intersection was found it is assigned the time of the
174 /// intersection along the world ray.
175 bool intersectsWS(const RayType& wRay, RealType &wTime) const
176 {
177 if (!mTester.setWorldRay(wRay)) return false;//missed bbox
178 wTime = mTester.getWorldTime();
179 return math::LevelSetHDDA<TreeT, NodeLevel>::test(mTester);
180 }
181
182 /// @brief Return @c true if the world-space ray intersects the level set.
183 /// @param wRay ray represented in world space.
184 /// @param world if an intersection was found it is assigned the
185 /// intersection point in world space, otherwise it is unchanged
186 bool intersectsWS(const RayType& wRay, Vec3Type& world) const
187 {
188 if (!mTester.setWorldRay(wRay)) return false;//missed bbox
189 if (!math::LevelSetHDDA<TreeT, NodeLevel>::test(mTester)) return false;//missed level set
190 mTester.getWorldPos(world);
191 return true;
192 }
193
194 /// @brief Return @c true if the world-space ray intersects the level set.
195 /// @param wRay ray represented in world space.
196 /// @param world if an intersection was found it is assigned the
197 /// intersection point in world space, otherwise it is unchanged.
198 /// @param wTime if an intersection was found it is assigned the time of the
199 /// intersection along the world ray.
200 bool intersectsWS(const RayType& wRay, Vec3Type& world, RealType &wTime) const
201 {
202 if (!mTester.setWorldRay(wRay)) return false;//missed bbox
203 if (!math::LevelSetHDDA<TreeT, NodeLevel>::test(mTester)) return false;//missed level set
204 mTester.getWorldPos(world);
205 wTime = mTester.getWorldTime();
206 return true;
207 }
208
209 /// @brief Return @c true if the world-space ray intersects the level set.
210 /// @param wRay ray represented in world space.
211 /// @param world if an intersection was found it is assigned the
212 /// intersection point in world space, otherwise it is unchanged.
213 /// @param normal if an intersection was found it is assigned the normal
214 /// of the level set surface in world space, otherwise it is unchanged.
215 bool intersectsWS(const RayType& wRay, Vec3Type& world, Vec3Type& normal) const
216 {
217 if (!mTester.setWorldRay(wRay)) return false;//missed bbox
218 if (!math::LevelSetHDDA<TreeT, NodeLevel>::test(mTester)) return false;//missed level set
219 mTester.getWorldPosAndNml(world, normal);
220 return true;
221 }
222
223 /// @brief Return @c true if the world-space ray intersects the level set.
224 /// @param wRay ray represented in world space.
225 /// @param world if an intersection was found it is assigned the
226 /// intersection point in world space, otherwise it is unchanged.
227 /// @param normal if an intersection was found it is assigned the normal
228 /// of the level set surface in world space, otherwise it is unchanged.
229 /// @param wTime if an intersection was found it is assigned the time of the
230 /// intersection along the world ray.
231 bool intersectsWS(const RayType& wRay, Vec3Type& world, Vec3Type& normal, RealType &wTime) const
232 {
233 if (!mTester.setWorldRay(wRay)) return false;//missed bbox
234 if (!math::LevelSetHDDA<TreeT, NodeLevel>::test(mTester)) return false;//missed level set
235 mTester.getWorldPosAndNml(world, normal);
236 wTime = mTester.getWorldTime();
237 return true;
238 }
239
240private:
241
242 mutable SearchImplT mTester;
243
244};// LevelSetRayIntersector
245
246
247////////////////////////////////////// VolumeRayIntersector //////////////////////////////////////
248
249
250/// @brief This class provides the public API for intersecting a ray
251/// with a generic (e.g. density) volume.
252/// @details Internally it performs the actual hierarchical tree node traversal.
253/// @warning Use the (default) copy-constructor to make sure each
254/// computational thread has their own instance of this class. This is
255/// important since it contains a ValueAccessor that is
256/// not thread-safe and a CoordBBox of the active voxels that should
257/// not be re-computed for each thread. However copying is very efficient.
258/// @par Example:
259/// @code
260/// // Create an instance for the master thread
261/// VolumeRayIntersector inter(grid);
262/// // For each additional thread use the copy constructor. This
263/// // amortizes the overhead of computing the bbox of the active voxels!
264/// VolumeRayIntersector inter2(inter);
265/// // Before each ray-traversal set the index ray.
266/// iter.setIndexRay(ray);
267/// // or world ray
268/// iter.setWorldRay(ray);
269/// // Now you can begin the ray-marching using consecutive calls to VolumeRayIntersector::march
270/// double t0=0, t1=0;// note the entry and exit times are with respect to the INDEX ray
271/// while ( inter.march(t0, t1) ) {
272/// // perform line-integration between t0 and t1
273/// }}
274/// @endcode
275template<typename GridT,
276 int NodeLevel = GridT::TreeType::RootNodeType::ChildNodeType::LEVEL,
277 typename RayT = math::Ray<Real> >
278 class VolumeRayIntersector
279{
280public:
281 using GridType = GridT;
282 using RayType = RayT;
283 using RealType = typename RayT::RealType;
284 using RootType = typename GridT::TreeType::RootNodeType;
285 using TreeT = tree::Tree<typename RootType::template ValueConverter<bool>::Type>;
286
287 static_assert(NodeLevel >= 0 && NodeLevel < int(TreeT::DEPTH)-1, "NodeLevel out of range");
288
289 /// @brief Grid constructor
290 /// @param grid Generic grid to intersect rays against.
291 /// @param dilationCount The number of voxel dilations performed
292 /// on (a boolean copy of) the input grid. This allows the
293 /// intersector to account for the size of interpolation kernels
294 /// in client code.
295 /// @throw RuntimeError if the voxels of the grid are not uniform
296 /// or the grid is empty.
297 VolumeRayIntersector(const GridT& grid, int dilationCount = 0)
298 : mIsMaster(true)
299 , mTree(new TreeT(grid.tree(), false, TopologyCopy()))
300 , mGrid(&grid)
301 , mAccessor(*mTree)
302 {
303 if (!grid.hasUniformVoxels() ) {
304 OPENVDB_THROW(RuntimeError,
305 "VolumeRayIntersector only supports uniform voxels!");
306 }
307 if ( grid.empty() ) {
308 OPENVDB_THROW(RuntimeError, "LinearSearchImpl does not supports empty grids");
309 }
310
311 // Dilate active voxels to better account for the size of interpolation kernels
312 tools::dilateActiveValues(*mTree, dilationCount, tools::NN_FACE, tools::IGNORE_TILES);
313
314 mTree->root().evalActiveBoundingBox(mBBox, /*visit individual voxels*/false);
315
316 mBBox.max().offset(1);//padding so the bbox of a node becomes (origin,origin + node_dim)
317 }
318
319 /// @brief Grid and BBox constructor
320 /// @param grid Generic grid to intersect rays against.
321 /// @param bbox The axis-aligned bounding-box in the index space of the grid.
322 /// @warning It is assumed that bbox = (min, min + dim) where min denotes
323 /// to the smallest grid coordinates and dim are the integer length of the bbox.
324 /// @throw RuntimeError if the voxels of the grid are not uniform
325 /// or the grid is empty.
326 VolumeRayIntersector(const GridT& grid, const math::CoordBBox& bbox)
327 : mIsMaster(true)
328 , mTree(new TreeT(grid.tree(), false, TopologyCopy()))
329 , mGrid(&grid)
330 , mAccessor(*mTree)
331 , mBBox(bbox)
332 {
333 if (!grid.hasUniformVoxels() ) {
334 OPENVDB_THROW(RuntimeError,
335 "VolumeRayIntersector only supports uniform voxels!");
336 }
337 if ( grid.empty() ) {
338 OPENVDB_THROW(RuntimeError, "LinearSearchImpl does not supports empty grids");
339 }
340 }
341
342 /// @brief Shallow copy constructor
343 /// @warning This copy constructor creates shallow copies of data
344 /// members of the instance passed as the argument. For
345 /// performance reasons we are not using shared pointers (their
346 /// mutex-lock impairs multi-threading).
347 VolumeRayIntersector(const VolumeRayIntersector& other)
348 : mIsMaster(false)
349 , mTree(other.mTree)//shallow copy
350 , mGrid(other.mGrid)//shallow copy
351 , mAccessor(*mTree)//initialize new (vs deep copy)
352 , mRay(other.mRay)//deep copy
353 , mTmax(other.mTmax)//deep copy
354 , mBBox(other.mBBox)//deep copy
355 {
356 }
357
358 /// @brief Destructor
359 ~VolumeRayIntersector() { if (mIsMaster) delete mTree; }
360
361 /// @brief Return @c false if the index ray misses the bbox of the grid.
362 /// @param iRay Ray represented in index space.
363 /// @warning Call this method (or setWorldRay) before the ray
364 /// traversal starts and use the return value to decide if further
365 /// marching is required.
366 inline bool setIndexRay(const RayT& iRay)
367 {
368 mRay = iRay;
369 const bool hit = mRay.clip(mBBox);
370 if (hit) mTmax = mRay.t1();
371 return hit;
372 }
373
374 /// @brief Return @c false if the world ray misses the bbox of the grid.
375 /// @param wRay Ray represented in world space.
376 /// @warning Call this method (or setIndexRay) before the ray
377 /// traversal starts and use the return value to decide if further
378 /// marching is required.
379 /// @details Since hit times are computed with respect to the ray
380 /// represented in index space of the current grid, it is
381 /// recommended that either the client code uses getIndexPos to
382 /// compute index position from hit times or alternatively keeps
383 /// an instance of the index ray and instead uses setIndexRay to
384 /// initialize the ray.
385 inline bool setWorldRay(const RayT& wRay)
386 {
387 return this->setIndexRay(wRay.worldToIndex(*mGrid));
388 }
389
390 inline typename RayT::TimeSpan march()
391 {
392 const typename RayT::TimeSpan t = mHDDA.march(mRay, mAccessor);
393 if (t.t1>0) mRay.setTimes(t.t1 + math::Delta<RealType>::value(), mTmax);
394 return t;
395 }
396
397 /// @brief Return @c true if the ray intersects active values,
398 /// i.e. either active voxels or tiles. Only when a hit is
399 /// detected are t0 and t1 updated with the corresponding entry
400 /// and exit times along the INDEX ray!
401 /// @note Note that t0 and t1 are only resolved at the node level
402 /// (e.g. a LeafNode with active voxels) as opposed to the individual
403 /// active voxels.
404 /// @param t0 If the return value > 0 this is the time of the
405 /// first hit of an active tile or leaf.
406 /// @param t1 If the return value > t0 this is the time of the
407 /// first hit (> t0) of an inactive tile or exit point of the
408 /// BBOX for the leaf nodes.
409 /// @warning t0 and t1 are computed with respect to the ray represented in
410 /// index space of the current grid, not world space!
411 inline bool march(RealType& t0, RealType& t1)
412 {
413 const typename RayT::TimeSpan t = this->march();
414 t.get(t0, t1);
415 return t.valid();
416 }
417
418 /// @brief Generates a list of hits along the ray.
419 ///
420 /// @param list List of hits represented as time spans.
421 ///
422 /// @note ListType is a list of RayType::TimeSpan and is required to
423 /// have the two methods: clear() and push_back(). Thus, it could
424 /// be std::vector<typename RayType::TimeSpan> or
425 /// std::deque<typename RayType::TimeSpan>.
426 template <typename ListType>
427 inline void hits(ListType& list)
428 {
429 mHDDA.hits(mRay, mAccessor, list);
430 }
431
432 /// @brief Return the floating-point index position along the
433 /// current index ray at the specified time.
434 inline Vec3R getIndexPos(RealType time) const { return mRay(time); }
435
436 /// @brief Return the floating-point world position along the
437 /// current index ray at the specified time.
438 inline Vec3R getWorldPos(RealType time) const { return mGrid->indexToWorld(mRay(time)); }
439
440 inline RealType getWorldTime(RealType time) const
441 {
442 return time*mGrid->transform().baseMap()->applyJacobian(mRay.dir()).length();
443 }
444
445 /// @brief Return a const reference to the input grid.
446 const GridT& grid() const { return *mGrid; }
447
448 /// @brief Return a const reference to the (potentially dilated)
449 /// bool tree used to accelerate the ray marching.
450 const TreeT& tree() const { return *mTree; }
451
452 /// @brief Return a const reference to the BBOX of the grid
453 const math::CoordBBox& bbox() const { return mBBox; }
454
455 /// @brief Print bbox, statistics, memory usage and other information.
456 /// @param os a stream to which to write textual information
457 /// @param verboseLevel 1: print bbox only; 2: include boolean tree
458 /// statistics; 3: include memory usage
459 void print(std::ostream& os = std::cout, int verboseLevel = 1)
460 {
461 if (verboseLevel>0) {
462 os << "BBox: " << mBBox << std::endl;
463 if (verboseLevel==2) {
464 mTree->print(os, 1);
465 } else if (verboseLevel>2) {
466 mTree->print(os, 2);
467 }
468 }
469 }
470
471private:
472 using AccessorT = typename tree::ValueAccessor<const TreeT,/*IsSafe=*/false>;
473
474 const bool mIsMaster;
475 TreeT* mTree;
476 const GridT* mGrid;
477 AccessorT mAccessor;
478 RayT mRay;
479 RealType mTmax;
480 math::CoordBBox mBBox;
481 math::VolumeHDDA<TreeT, RayType, NodeLevel> mHDDA;
482
483};// VolumeRayIntersector
484
485
486//////////////////////////////////////// LinearSearchImpl ////////////////////////////////////////
487
488
489/// @brief Implements linear iterative search for an iso-value of
490/// the level set along the direction of the ray.
491///
492/// @note Since this class is used internally in
493/// LevelSetRayIntersector (define above) and LevelSetHDDA (defined below)
494/// client code should never interact directly with its API. This also
495/// explains why we are not concerned with the fact that several of
496/// its methods are unsafe to call unless roots were already detected.
497///
498/// @details It is approximate due to the limited number of iterations
499/// which can can be defined with a template parameter. However the default value
500/// has proven surprisingly accurate and fast. In fact more iterations
501/// are not guaranteed to give significantly better results.
502///
503/// @warning Since the root-searching algorithm is approximate
504/// (first-order) it is possible to miss intersections if the
505/// iso-value is too close to the inside or outside of the narrow
506/// band (typically a distance less than a voxel unit).
507///
508/// @warning Since this class internally stores a ValueAccessor it is NOT thread-safe,
509/// so make sure to give each thread its own instance. This of course also means that
510/// the cost of allocating an instance should (if possible) be amortized over
511/// as many ray intersections as possible.
512template<typename GridT, int Iterations, typename RealT>
513 class LinearSearchImpl
514{
515public:
516 using RayT = math::Ray<RealT>;
517 using VecT = math::Vec3<RealT>;
518 using ValueT = typename GridT::ValueType;
519 using AccessorT = typename GridT::ConstAccessor;
520 using StencilT = math::BoxStencil<GridT>;
521
522 /// @brief Constructor from a grid.
523 /// @throw RunTimeError if the grid is empty.
524 /// @throw ValueError if the isoValue is not inside the narrow-band.
525 LinearSearchImpl(const GridT& grid, const ValueT& isoValue = zeroVal<ValueT>())
526 : mStencil(grid),
527 mIsoValue(isoValue),
528 mMinValue(isoValue - ValueT(2 * grid.voxelSize()[0])),
529 mMaxValue(isoValue + ValueT(2 * grid.voxelSize()[0]))
530 {
531 if ( grid.empty() ) {
532 OPENVDB_THROW(RuntimeError, "LinearSearchImpl does not supports empty grids");
533 }
534 if (mIsoValue<= -grid.background() ||
535 mIsoValue>= grid.background() ){
536 OPENVDB_THROW(ValueError, "The iso-value must be inside the narrow-band!");
537 }
538 grid.tree().root().evalActiveBoundingBox(mBBox, /*visit individual voxels*/false);
539 }
540
541 /// @brief Return the iso-value used for ray-intersections
542 const ValueT& getIsoValue() const { return mIsoValue; }
543
544 /// @brief Return @c false if the ray misses the bbox of the grid.
545 /// @param iRay Ray represented in index space.
546 /// @warning Call this method before the ray traversal starts.
547 inline bool setIndexRay(const RayT& iRay)
548 {
549 mRay = iRay;
550 return mRay.clip(mBBox);//did it hit the bbox
551 }
552
553 /// @brief Return @c false if the ray misses the bbox of the grid.
554 /// @param wRay Ray represented in world space.
555 /// @warning Call this method before the ray traversal starts.
556 inline bool setWorldRay(const RayT& wRay)
557 {
558 mRay = wRay.worldToIndex(mStencil.grid());
559 return mRay.clip(mBBox);//did it hit the bbox
560 }
561
562 /// @brief Get the intersection point in index space.
563 /// @param xyz The position in index space of the intersection.
564 inline void getIndexPos(VecT& xyz) const { xyz = mRay(mTime); }
565
566 /// @brief Get the intersection point in world space.
567 /// @param xyz The position in world space of the intersection.
568 inline void getWorldPos(VecT& xyz) const { xyz = mStencil.grid().indexToWorld(mRay(mTime)); }
569
570 /// @brief Get the intersection point and normal in world space
571 /// @param xyz The position in world space of the intersection.
572 /// @param nml The surface normal in world space of the intersection.
573 inline void getWorldPosAndNml(VecT& xyz, VecT& nml)
574 {
575 this->getIndexPos(xyz);
576 mStencil.moveTo(xyz);
577 nml = mStencil.gradient(xyz);
578 nml.normalize();
579 xyz = mStencil.grid().indexToWorld(xyz);
580 }
581
582 /// @brief Return the time of intersection along the index ray.
583 inline RealT getIndexTime() const { return mTime; }
584
585 /// @brief Return the time of intersection along the world ray.
586 inline RealT getWorldTime() const
587 {
588 return mTime*mStencil.grid().transform().baseMap()->applyJacobian(mRay.dir()).length();
589 }
590
591private:
592
593 /// @brief Initiate the local voxel intersection test.
594 /// @warning Make sure to call this method before the local voxel intersection test.
595 inline void init(RealT t0)
596 {
597 mT[0] = t0;
598 mV[0] = static_cast<ValueT>(this->interpValue(t0));
599 }
600
601 inline void setRange(RealT t0, RealT t1) { mRay.setTimes(t0, t1); }
602
603 /// @brief Return a const reference to the ray.
604 inline const RayT& ray() const { return mRay; }
605
606 /// @brief Return true if a node of the specified type exists at ijk.
607 template <typename NodeT>
608 inline bool hasNode(const Coord& ijk)
609 {
610 return mStencil.accessor().template probeConstNode<NodeT>(ijk) != nullptr;
611 }
612
613 /// @brief Return @c true if an intersection is detected.
614 /// @param ijk Grid coordinate of the node origin or voxel being tested.
615 /// @param time Time along the index ray being tested.
616 /// @warning Only if an intersection is detected is it safe to
617 /// call getIndexPos, getWorldPos and getWorldPosAndNml!
618 inline bool operator()(const Coord& ijk, RealT time)
619 {
620 ValueT V;
621 if (mStencil.accessor().probeValue(ijk, V) &&//within narrow band
622 V>mMinValue && V<mMaxValue) {// and close to iso-value?
623 mT[1] = time;
624 mV[1] = static_cast<ValueT>(this->interpValue(time));
625 if (math::ZeroCrossing(mV[0], mV[1])) {
626 mTime = this->interpTime();
627 OPENVDB_NO_UNREACHABLE_CODE_WARNING_BEGIN
628 for (int n=0; Iterations>0 && n<Iterations; ++n) {//resolved at compile-time
629 V = static_cast<ValueT>(this->interpValue(mTime));
630 const int m = math::ZeroCrossing(mV[0], V) ? 1 : 0;
631 mV[m] = V;
632 mT[m] = mTime;
633 mTime = this->interpTime();
634 }
635 OPENVDB_NO_UNREACHABLE_CODE_WARNING_END
636 return true;
637 }
638 mT[0] = mT[1];
639 mV[0] = mV[1];
640 }
641 return false;
642 }
643
644 inline RealT interpTime()
645 {
646 OPENVDB_ASSERT( math::isApproxLarger(mT[1], mT[0], RealT(1e-6) ) );
647 return mT[0]+(mT[1]-mT[0])*mV[0]/(mV[0]-mV[1]);
648 }
649
650 inline RealT interpValue(RealT time)
651 {
652 const VecT pos = mRay(time);
653 mStencil.moveTo(pos);
654 return mStencil.interpolation(pos) - mIsoValue;
655 }
656
657 template<typename, int> friend struct math::LevelSetHDDA;
658
659 RayT mRay;
660 StencilT mStencil;
661 RealT mTime;//time of intersection
662 ValueT mV[2];
663 RealT mT[2];
664 const ValueT mIsoValue, mMinValue, mMaxValue;
665 math::CoordBBox mBBox;
666};// LinearSearchImpl
667
668} // namespace tools
669} // namespace OPENVDB_VERSION_NAME
670} // namespace openvdb
671
672#endif // OPENVDB_TOOLS_RAYINTERSECTOR_HAS_BEEN_INCLUDED
Assert.h
OPENVDB_ASSERT
#define OPENVDB_ASSERT(X)
Definition Assert.h:41
DDA.h
Digital Differential Analyzers specialized for VDB.
Grid.h
Math.h
General-purpose arithmetic and comparison routines, most of which accept arbitrary value types (or at...
Morphology.h
Implementation of morphological dilation and erosion.
OPENVDB_NO_UNREACHABLE_CODE_WARNING_END
#define OPENVDB_NO_UNREACHABLE_CODE_WARNING_END
Definition Platform.h:164
OPENVDB_NO_UNREACHABLE_CODE_WARNING_BEGIN
#define OPENVDB_NO_UNREACHABLE_CODE_WARNING_BEGIN
Definition Platform.h:163
openvdb::v12_1::TopologyCopy
Tag dispatch class that distinguishes topology copy constructors from deep copy constructors.
Definition Types.h:754
openvdb::v12_1::math::BoxStencil
Definition Stencils.h:301
openvdb::v12_1::math::CoordBBox
Axis-aligned bounding box of signed integer coordinates.
Definition Coord.h:252
openvdb::v12_1::math::Ray
Definition Ray.h:28
openvdb::v12_1::math::Ray::worldToIndex
Ray worldToIndex(const GridType &grid) const
Return a new ray in the index space of the specified grid, assuming the existing ray is represented i...
Definition Ray.h:172
openvdb::v12_1::math::Ray::clip
bool clip(const Vec3T &center, RealT radius)
Return true if this ray intersects the specified sphere.
Definition Ray.h:218
openvdb::v12_1::math::Vec3
Definition Vec3.h:25
openvdb::v12_1::math::Vec3::normalize
bool normalize(T eps=T(1.0e-7))
this = normalized this
Definition Vec3.h:363
openvdb::v12_1::math::VolumeHDDA
Helper class that implements Hierarchical Digital Differential Analyzers for ray intersections agains...
Definition DDA.h:189
openvdb::v12_1::tools::LevelSetRayIntersector::intersectsWS
bool intersectsWS(const RayType &wRay) const
Return true if the world-space ray intersects the level set.
Definition RayIntersector.h:165
openvdb::v12_1::tools::LevelSetRayIntersector::intersectsWS
bool intersectsWS(const RayType &wRay, Vec3Type &world, RealType &wTime) const
Return true if the world-space ray intersects the level set.
Definition RayIntersector.h:200
openvdb::v12_1::tools::LevelSetRayIntersector::intersectsIS
bool intersectsIS(const RayType &iRay, Vec3Type &xyz) const
Return true if the index-space ray intersects the level set.
Definition RayIntersector.h:140
openvdb::v12_1::tools::LevelSetRayIntersector::TreeT
typename GridT::TreeType TreeT
Definition RayIntersector.h:91
openvdb::v12_1::tools::LevelSetRayIntersector::getIsoValue
const ValueT & getIsoValue() const
Return the iso-value used for ray-intersections.
Definition RayIntersector.h:115
openvdb::v12_1::tools::LevelSetRayIntersector::intersectsIS
bool intersectsIS(const RayType &iRay, Vec3Type &xyz, RealType &iTime) const
Return true if the index-space ray intersects the level set.
Definition RayIntersector.h:154
openvdb::v12_1::tools::LevelSetRayIntersector::LevelSetRayIntersector
LevelSetRayIntersector(const GridT &grid, const ValueT &isoValue=zeroVal< ValueT >())
Constructor.
Definition RayIntersector.h:100
openvdb::v12_1::tools::LevelSetRayIntersector::RayType
RayT RayType
Definition RayIntersector.h:87
openvdb::v12_1::tools::LevelSetRayIntersector::intersectsWS
bool intersectsWS(const RayType &wRay, RealType &wTime) const
Return true if the world-space ray intersects the level set.
Definition RayIntersector.h:175
openvdb::v12_1::tools::LevelSetRayIntersector::intersectsIS
bool intersectsIS(const RayType &iRay) const
Return true if the index-space ray intersects the level set.
Definition RayIntersector.h:119
openvdb::v12_1::tools::LevelSetRayIntersector::Vec3Type
typename RayT::Vec3T Vec3Type
Definition RayIntersector.h:89
openvdb::v12_1::tools::LevelSetRayIntersector::intersectsWS
bool intersectsWS(const RayType &wRay, Vec3Type &world) const
Return true if the world-space ray intersects the level set.
Definition RayIntersector.h:186
openvdb::v12_1::tools::LevelSetRayIntersector::intersectsWS
bool intersectsWS(const RayType &wRay, Vec3Type &world, Vec3Type &normal) const
Return true if the world-space ray intersects the level set.
Definition RayIntersector.h:215
openvdb::v12_1::tools::LevelSetRayIntersector::ValueT
typename GridT::ValueType ValueT
Definition RayIntersector.h:90
openvdb::v12_1::tools::LevelSetRayIntersector::RealType
typename RayT::RealType RealType
Definition RayIntersector.h:88
openvdb::v12_1::tools::LevelSetRayIntersector::GridType
GridT GridType
Definition RayIntersector.h:86
openvdb::v12_1::tools::LevelSetRayIntersector::intersectsWS
bool intersectsWS(const RayType &wRay, Vec3Type &world, Vec3Type &normal, RealType &wTime) const
Return true if the world-space ray intersects the level set.
Definition RayIntersector.h:231
openvdb::v12_1::tools::LevelSetRayIntersector::intersectsIS
bool intersectsIS(const RayType &iRay, RealType &iTime) const
Return true if the index-space ray intersects the level set.
Definition RayIntersector.h:129
openvdb::v12_1::tools::LinearSearchImpl::setIndexRay
bool setIndexRay(const RayT &iRay)
Return false if the ray misses the bbox of the grid.
Definition RayIntersector.h:547
openvdb::v12_1::tools::LinearSearchImpl::getIndexPos
void getIndexPos(VecT &xyz) const
Get the intersection point in index space.
Definition RayIntersector.h:564
openvdb::v12_1::tools::LinearSearchImpl::getIndexTime
RealT getIndexTime() const
Return the time of intersection along the index ray.
Definition RayIntersector.h:583
openvdb::v12_1::tools::LinearSearchImpl::LinearSearchImpl
LinearSearchImpl(const GridT &grid, const ValueT &isoValue=zeroVal< ValueT >())
Constructor from a grid.
Definition RayIntersector.h:525
openvdb::v12_1::tools::LinearSearchImpl::StencilT
math::BoxStencil< GridT > StencilT
Definition RayIntersector.h:520
openvdb::v12_1::tools::LinearSearchImpl::getIsoValue
const ValueT & getIsoValue() const
Return the iso-value used for ray-intersections.
Definition RayIntersector.h:542
openvdb::v12_1::tools::LinearSearchImpl::VecT
math::Vec3< RealT > VecT
Definition RayIntersector.h:517
openvdb::v12_1::tools::LinearSearchImpl::AccessorT
typename GridT::ConstAccessor AccessorT
Definition RayIntersector.h:519
openvdb::v12_1::tools::LinearSearchImpl::RayT
math::Ray< RealT > RayT
Definition RayIntersector.h:516
openvdb::v12_1::tools::LinearSearchImpl::ValueT
typename GridT::ValueType ValueT
Definition RayIntersector.h:518
openvdb::v12_1::tools::LinearSearchImpl::setWorldRay
bool setWorldRay(const RayT &wRay)
Return false if the ray misses the bbox of the grid.
Definition RayIntersector.h:556
openvdb::v12_1::tools::LinearSearchImpl::getWorldTime
RealT getWorldTime() const
Return the time of intersection along the world ray.
Definition RayIntersector.h:586
openvdb::v12_1::tools::LinearSearchImpl::getWorldPos
void getWorldPos(VecT &xyz) const
Get the intersection point in world space.
Definition RayIntersector.h:568
openvdb::v12_1::tools::LinearSearchImpl::getWorldPosAndNml
void getWorldPosAndNml(VecT &xyz, VecT &nml)
Get the intersection point and normal in world space.
Definition RayIntersector.h:573
openvdb::v12_1::tools::VolumeRayIntersector::setIndexRay
bool setIndexRay(const RayT &iRay)
Return false if the index ray misses the bbox of the grid.
Definition RayIntersector.h:366
openvdb::v12_1::tools::VolumeRayIntersector::bbox
const math::CoordBBox & bbox() const
Return a const reference to the BBOX of the grid.
Definition RayIntersector.h:453
openvdb::v12_1::tools::VolumeRayIntersector::RootType
typename GridT::TreeType::RootNodeType RootType
Definition RayIntersector.h:284
openvdb::v12_1::tools::VolumeRayIntersector::~VolumeRayIntersector
~VolumeRayIntersector()
Destructor.
Definition RayIntersector.h:359
openvdb::v12_1::tools::VolumeRayIntersector::VolumeRayIntersector
VolumeRayIntersector(const VolumeRayIntersector &other)
Shallow copy constructor.
Definition RayIntersector.h:347
openvdb::v12_1::tools::VolumeRayIntersector::VolumeRayIntersector
VolumeRayIntersector(const GridT &grid, const math::CoordBBox &bbox)
Grid and BBox constructor.
Definition RayIntersector.h:326
openvdb::v12_1::tools::VolumeRayIntersector::getWorldTime
RealType getWorldTime(RealType time) const
Definition RayIntersector.h:440
openvdb::v12_1::tools::VolumeRayIntersector::march
bool march(RealType &t0, RealType &t1)
Return true if the ray intersects active values, i.e. either active voxels or tiles....
Definition RayIntersector.h:411
openvdb::v12_1::tools::VolumeRayIntersector::print
void print(std::ostream &os=std::cout, int verboseLevel=1)
Print bbox, statistics, memory usage and other information.
Definition RayIntersector.h:459
openvdb::v12_1::tools::VolumeRayIntersector::TreeT
tree::Tree< typename RootType::template ValueConverter< bool >::Type > TreeT
Definition RayIntersector.h:285
openvdb::v12_1::tools::VolumeRayIntersector::getWorldPos
Vec3R getWorldPos(RealType time) const
Return the floating-point world position along the current index ray at the specified time.
Definition RayIntersector.h:438
openvdb::v12_1::tools::VolumeRayIntersector::RayType
RayT RayType
Definition RayIntersector.h:282
openvdb::v12_1::tools::VolumeRayIntersector::hits
void hits(ListType &list)
Generates a list of hits along the ray.
Definition RayIntersector.h:427
openvdb::v12_1::tools::VolumeRayIntersector::tree
const TreeT & tree() const
Return a const reference to the (potentially dilated) bool tree used to accelerate the ray marching.
Definition RayIntersector.h:450
openvdb::v12_1::tools::VolumeRayIntersector::grid
const GridT & grid() const
Return a const reference to the input grid.
Definition RayIntersector.h:446
openvdb::v12_1::tools::VolumeRayIntersector::VolumeRayIntersector
VolumeRayIntersector(const GridT &grid, int dilationCount=0)
Grid constructor.
Definition RayIntersector.h:297
openvdb::v12_1::tools::VolumeRayIntersector::setWorldRay
bool setWorldRay(const RayT &wRay)
Return false if the world ray misses the bbox of the grid.
Definition RayIntersector.h:385
openvdb::v12_1::tools::VolumeRayIntersector::getIndexPos
Vec3R getIndexPos(RealType time) const
Return the floating-point index position along the current index ray at the specified time.
Definition RayIntersector.h:434
openvdb::v12_1::tools::VolumeRayIntersector::RealType
typename RayT::RealType RealType
Definition RayIntersector.h:283
openvdb::v12_1::tools::VolumeRayIntersector::GridType
GridT GridType
Definition RayIntersector.h:281
openvdb::v12_1::tools::VolumeRayIntersector::march
RayT::TimeSpan march()
Definition RayIntersector.h:390
openvdb::v12_1::tree::Tree
Definition Tree.h:195
openvdb::v12_1::tree::Tree::DEPTH
static const Index DEPTH
Definition Tree.h:205
openvdb::v12_1::tools::NN_FACE
@ NN_FACE
Definition Morphology.h:60
openvdb::v12_1::tools::if
if(shared)
Definition ValueTransformer.h:596
openvdb::v12_1::tools::dilateActiveValues
void dilateActiveValues(TreeOrLeafManagerT &tree, const int iterations=1, const NearestNeighbors nn=NN_FACE, const TilePolicy mode=PRESERVE_TILES, const bool threaded=true)
Topologically dilate all active values (i.e. both voxels and tiles) in a tree using one of three near...
Definition Morphology.h:1057
openvdb::v12_1::tools::IGNORE_TILES
@ IGNORE_TILES
Definition Morphology.h:82
openvdb::v12_1::tree::ValueAccessor
ValueAccessorImpl< TreeType, IsSafe, MutexType, openvdb::make_index_sequence< CacheLevels > > ValueAccessor
Default alias for a ValueAccessor. This is simply a helper alias for the generic definition but takes...
Definition ValueAccessor.h:86
openvdb::v12_1::GRID_LEVEL_SET
@ GRID_LEVEL_SET
Definition Types.h:526
openvdb::v12_1::zeroVal
constexpr T zeroVal()
Return the value of type T that corresponds to zero.
Definition Math.h:70
openvdb::v12_1::Vec3R
math::Vec3< Real > Vec3R
Definition Types.h:72
openvdb
Definition Exceptions.h:13
Types.h
Ray.h
A Ray class.
Stencils.h
Defines various finite difference stencils by means of the "curiously recurring template pattern" on ...
openvdb::v12_1::math::Delta::value
static T value()
Definition Math.h:155
openvdb::v12_1::math::LevelSetHDDA
Helper class that implements Hierarchical Digital Differential Analyzers and is specialized for ray i...
Definition DDA.h:146
openvdb::v12_1::math::LevelSetHDDA::test
static bool test(TesterT &tester)
Definition DDA.h:151
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