OpenVDB: LevelSetSphere.h Source File

OpenVDB 8.0.0

LevelSetSphere.h
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1 // Copyright Contributors to the OpenVDB Project
2 // SPDX-License-Identifier: MPL-2.0
11
12 #ifndef OPENVDB_TOOLS_LEVELSETSPHERE_HAS_BEEN_INCLUDED
13 #define OPENVDB_TOOLS_LEVELSETSPHERE_HAS_BEEN_INCLUDED
14
15 #include <openvdb/Grid.h>
16 #include <openvdb/Types.h>
17 #include <openvdb/math/Math.h>
18 #include <openvdb/util/NullInterrupter.h>
19 #include "SignedFloodFill.h"
20 #include <type_traits>
21
22 #include <tbb/enumerable_thread_specific.h>
23 #include <tbb/parallel_for.h>
24 #include <tbb/parallel_reduce.h>
25 #include <tbb/blocked_range.h>
26 #include <thread>
27
28 namespace openvdb {
29 OPENVDB_USE_VERSION_NAMESPACE
30 namespace OPENVDB_VERSION_NAME {
31 namespace tools {
32
47 template<typename GridType, typename InterruptT>
48 typename GridType::Ptr
49 createLevelSetSphere(float radius, const openvdb::Vec3f& center, float voxelSize,
50 float halfWidth = float(LEVEL_SET_HALF_WIDTH),
51 InterruptT* interrupt = nullptr, bool threaded = true);
52
66 template<typename GridType>
67 typename GridType::Ptr
68 createLevelSetSphere(float radius, const openvdb::Vec3f& center, float voxelSize,
69 float halfWidth = float(LEVEL_SET_HALF_WIDTH), bool threaded = true)
70 {
71 return createLevelSetSphere<GridType, util::NullInterrupter>(radius,center,voxelSize,halfWidth,nullptr,threaded);
72 }
73
74
76
77
84 template<typename GridT, typename InterruptT = util::NullInterrupter>
85 class LevelSetSphere
86 {
87 public:
88 using TreeT = typename GridT::TreeType;
89 using ValueT = typename GridT::ValueType;
90 using Vec3T = typename math::Vec3<ValueT>;
91 static_assert(std::is_floating_point<ValueT>::value,
92 "level set grids must have scalar, floating-point value types");
93
104 LevelSetSphere(ValueT radius, const Vec3T &center, InterruptT* interrupt = nullptr)
105 : mRadius(radius), mCenter(center), mInterrupt(interrupt)
106 {
107 if (mRadius<=0) OPENVDB_THROW(ValueError, "radius must be positive");
108 }
109
115 typename GridT::Ptr getLevelSet(ValueT voxelSize, ValueT halfWidth, bool threaded = true)
116 {
117 mGrid = createLevelSet<GridT>(voxelSize, halfWidth);
118 this->rasterSphere(voxelSize, halfWidth, threaded);
119 mGrid->setGridClass(GRID_LEVEL_SET);
120 return mGrid;
121 }
122
123 private:
124 void rasterSphere(ValueT dx, ValueT w, bool threaded)
125 {
126 if (!(dx>0.0f)) OPENVDB_THROW(ValueError, "voxel size must be positive");
127 if (!(w>1)) OPENVDB_THROW(ValueError, "half-width must be larger than one");
128
129 // Define radius of sphere and narrow-band in voxel units
130 const ValueT r0 = mRadius/dx, rmax = r0 + w;
131
132 // Radius below the Nyquist frequency
133 if (r0 < 1.5f) return;
134
135 // Define center of sphere in voxel units
136 const Vec3T c(mCenter[0]/dx, mCenter[1]/dx, mCenter[2]/dx);
137
138 // Define bounds of the voxel coordinates
139 const int imin=math::Floor(c[0]-rmax), imax=math::Ceil(c[0]+rmax);
140 const int jmin=math::Floor(c[1]-rmax), jmax=math::Ceil(c[1]+rmax);
141 const int kmin=math::Floor(c[2]-rmax), kmax=math::Ceil(c[2]+rmax);
142
143 // Allocate a ValueAccessor for accelerated random access
144 typename GridT::Accessor accessor = mGrid->getAccessor();
145
146 if (mInterrupt) mInterrupt->start("Generating level set of sphere");
147
148 tbb::enumerable_thread_specific<TreeT> pool(mGrid->tree());
149
150 auto kernel = [&](const tbb::blocked_range<int>& r) {
151 openvdb::Coord ijk;
152 int &i = ijk[0], &j = ijk[1], &k = ijk[2], m=1;
153 TreeT &tree = pool.local();
154 typename GridT::Accessor acc(tree);
155 // Compute signed distances to sphere using leapfrogging in k
156 for (i = r.begin(); i <= r.end(); ++i) {
157 if (util::wasInterrupted(mInterrupt)) return;
158 const auto x2 = math::Pow2(ValueT(i) - c[0]);
159 for (j = jmin; j <= jmax; ++j) {
160 const auto x2y2 = math::Pow2(ValueT(j) - c[1]) + x2;
161 for (k = kmin; k <= kmax; k += m) {
162 m = 1;
163 // Distance in voxel units to sphere
164 const auto v = math::Sqrt(x2y2 + math::Pow2(ValueT(k)-c[2]))-r0;
165 const auto d = math::Abs(v);
166 if (d < w) { // inside narrow band
167 acc.setValue(ijk, dx*v);// distance in world units
168 } else { // outside narrow band
169 m += math::Floor(d-w);// leapfrog
170 }
171 }//end leapfrog over k
172 }//end loop over j
173 }//end loop over i
174 };// kernel
175
176 if (threaded) {
177 // The code blow is making use of a TLS container to minimize the number of concurrent trees
178 // initially populated by tbb::parallel_for and subsequently merged by tbb::parallel_reduce.
179 // Experiments have demonstrated this approach to outperform others, including serial reduction
180 // and a custom concurrent reduction implementation.
181 tbb::parallel_for(tbb::blocked_range<int>(imin, imax, 128), kernel);
182 using RangeT = tbb::blocked_range<typename tbb::enumerable_thread_specific<TreeT>::iterator>;
183 struct Op {
184 const bool mDelete;
185 TreeT *mTree;
186 Op(TreeT &tree) : mDelete(false), mTree(&tree) {}
187 Op(const Op& other, tbb::split) : mDelete(true), mTree(new TreeT(other.mTree->background())) {}
188 ~Op() { if (mDelete) delete mTree; }
189 void operator()(RangeT &r) { for (auto i=r.begin(); i!=r.end(); ++i) this->merge(*i);}
190 void join(Op &other) { this->merge(*(other.mTree)); }
191 void merge(TreeT &tree) { mTree->merge(tree, openvdb::MERGE_ACTIVE_STATES); }
192 } op( mGrid->tree() );
193 tbb::parallel_reduce(RangeT(pool.begin(), pool.end(), 4), op);
194 } else {
195 kernel(tbb::blocked_range<int>(imin, imax));//serial
196 mGrid->tree().merge(*pool.begin(), openvdb::MERGE_ACTIVE_STATES);
197 }
198
199 // Define consistent signed distances outside the narrow-band
200 tools::signedFloodFill(mGrid->tree(), threaded);
201
202 if (mInterrupt) mInterrupt->end();
203 }
204
205 const ValueT mRadius;
206 const Vec3T mCenter;
207 InterruptT* mInterrupt;
208 typename GridT::Ptr mGrid;
209 };// LevelSetSphere
210
211
213
214
215 template<typename GridType, typename InterruptT>
216 typename GridType::Ptr
217 createLevelSetSphere(float radius, const openvdb::Vec3f& center, float voxelSize,
218 float halfWidth, InterruptT* interrupt, bool threaded)
219 {
220 // GridType::ValueType is required to be a floating-point scalar.
221 static_assert(std::is_floating_point<typename GridType::ValueType>::value,
222 "level set grids must have scalar, floating-point value types");
223
224 using ValueT = typename GridType::ValueType;
225 LevelSetSphere<GridType, InterruptT> factory(ValueT(radius), center, interrupt);
226 return factory.getLevelSet(ValueT(voxelSize), ValueT(halfWidth), threaded);
227 }
228
229 } // namespace tools
230 } // namespace OPENVDB_VERSION_NAME
231 } // namespace openvdb
232
233 #endif // OPENVDB_TOOLS_LEVELSETSPHERE_HAS_BEEN_INCLUDED
Types.h
openvdb::v8_2::math::Sqrt
float Sqrt(float x)
Return the square root of a floating-point value.
Definition: Math.h:764
openvdb::v8_2::math::Ceil
int Ceil(float x)
Return the ceiling of x.
Definition: Math.h:859
openvdb::v8_2::math::Coord
Signed (x, y, z) 32-bit integer coordinates.
Definition: Coord.h:26
openvdb::v8_2::MERGE_ACTIVE_STATES
@ MERGE_ACTIVE_STATES
Definition: openvdb/Types.h:367
OPENVDB_THROW
#define OPENVDB_THROW(exception, message)
Definition: openvdb/Exceptions.h:74
Grid.h
openvdb::v8_2::GRID_LEVEL_SET
@ GRID_LEVEL_SET
Definition: openvdb/Types.h:315
openvdb::v8_2::math::Vec3
Definition: Vec3.h:24
openvdb::v8_2::tools::LevelSetSphere::getLevelSet
GridT::Ptr getLevelSet(ValueT voxelSize, ValueT halfWidth, bool threaded=true)
Definition: LevelSetSphere.h:115
Math.h
General-purpose arithmetic and comparison routines, most of which accept arbitrary value types (or at...
openvdb::v8_2::tools::LevelSetSphere::TreeT
typename GridT::TreeType TreeT
Definition: LevelSetSphere.h:88
openvdb::v8_2::tools::LevelSetSphere::LevelSetSphere
LevelSetSphere(ValueT radius, const Vec3T &center, InterruptT *interrupt=nullptr)
Constructor.
Definition: LevelSetSphere.h:104
openvdb::v8_2::ValueError
Definition: openvdb/Exceptions.h:65
openvdb::v8_2::LEVEL_SET_HALF_WIDTH
static const Real LEVEL_SET_HALF_WIDTH
Definition: openvdb/Types.h:321
openvdb::v8_2::tools::LevelSetSphere::Vec3T
typename math::Vec3< ValueT > Vec3T
Definition: LevelSetSphere.h:90
NullInterrupter.h
openvdb::v8_2::tools::LevelSetSphere::ValueT
typename GridT::ValueType ValueT
Definition: LevelSetSphere.h:89
openvdb::v8_2::util::wasInterrupted
bool wasInterrupted(T *i, int percent=-1)
Definition: NullInterrupter.h:49
OPENVDB_USE_VERSION_NAMESPACE
#define OPENVDB_USE_VERSION_NAMESPACE
Definition: version.h:153
openvdb::v8_2::math::Pow2
Type Pow2(Type x)
Return x2.
Definition: Math.h:551
openvdb::v8_2::tools::signedFloodFill
void signedFloodFill(TreeOrLeafManagerT &tree, bool threaded=true, size_t grainSize=1, Index minLevel=0)
Set the values of all inactive voxels and tiles of a narrow-band level set from the signs of the acti...
Definition: SignedFloodFill.h:266
openvdb::v8_2::math::Abs
Coord Abs(const Coord &xyz)
Definition: Coord.h:515
SignedFloodFill.h
Propagate the signs of distance values from the active voxels in the narrow band to the inactive valu...
OPENVDB_VERSION_NAME
#define OPENVDB_VERSION_NAME
The version namespace name for this library version.
Definition: version.h:101
openvdb::v8_2::tools::LevelSetSphere
Generates a signed distance field (or narrow band level set) to a single sphere.
Definition: LevelSetSphere.h:86
openvdb::v8_2::math::Floor
int Floor(float x)
Return the floor of x.
Definition: Math.h:851
openvdb
Definition: openvdb/Exceptions.h:13
openvdb::v8_2::tools::createLevelSetSphere
GridType::Ptr createLevelSetSphere(float radius, const openvdb::Vec3f &center, float voxelSize, float halfWidth=float(LEVEL_SET_HALF_WIDTH), bool threaded=true)
Return a grid of type GridType containing a narrow-band level set representation of a sphere.
Definition: LevelSetSphere.h:68