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//
// Copyright (c) 2012-2013 DreamWorks Animation LLC
//
// All rights reserved. This software is distributed under the
// Mozilla Public License 2.0 ( http://www.mozilla.org/MPL/2.0/ )
//
// Redistributions of source code must retain the above copyright
// and license notice and the following restrictions and disclaimer.
//
// * Neither the name of DreamWorks Animation nor the names of
// its contributors may be used to endorse or promote products derived
// from this software without specific prior written permission.
//
// THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
// "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
// LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
// A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
// OWNER OR CONTRIBUTORS BE LIABLE FOR ANY INDIRECT, INCIDENTAL,
// SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
// LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
// DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
// THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
// (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
// OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
// IN NO EVENT SHALL THE COPYRIGHT HOLDERS' AND CONTRIBUTORS' AGGREGATE
// LIABILITY FOR ALL CLAIMS REGARDLESS OF THEIR BASIS EXCEED US$250.00.
//
///////////////////////////////////////////////////////////////////////////
//
/// @file Interpolation.h
///
/// Sampler classes such as PointSampler and BoxSampler that are intended for use
/// with tools::GridTransformer should operate in voxel space and must adhere to
/// the interface described in the example below:
/// @code
/// struct MySampler
/// {
/// // Return a short name that can be used to identify this sampler
/// // in error messages and elsewhere.
/// const char* name() { return "mysampler"; }
///
/// // Return the radius of the sampling kernel in voxels, not including
/// // the center voxel. This is the number of voxels of padding that
/// // are added to all sides of a volume as a result of resampling.
/// int radius() { return 2; }
///
/// // Return true if scaling by a factor smaller than 0.5 (along any axis)
/// // should be handled via a mipmapping-like scheme of successive halvings
/// // of a grid's resolution, until the remaining scale factor is
/// // greater than or equal to 1/2. Set this to false only when high-quality
/// // scaling is not required.
/// bool mipmap() { return true; }
///
/// // Specify if sampling at a location that is collocated with a grid point
/// // is guaranteed to return the exact value at that grid point.
/// // For most sampling kernels, this should be false.
/// bool consistent() { return false; }
///
/// // Sample the tree at the given coordinates and return the result in val.
/// // Return true if the sampled value is active.
/// template<class TreeT>
/// bool sample(const TreeT& tree, const Vec3R& coord, typename TreeT::ValueType& val);
/// };
/// @endcode
#ifndef OPENVDB_TOOLS_INTERPOLATION_HAS_BEEN_INCLUDED
#define OPENVDB_TOOLS_INTERPOLATION_HAS_BEEN_INCLUDED
#include <cmath>
#include <boost/shared_ptr.hpp>
#include <openvdb/version.h> // for OPENVDB_VERSION_NAME
#include <openvdb/Platform.h> // for round()
#include <openvdb/math/Transform.h> // for Transform
#include <openvdb/Grid.h>
#include <openvdb/tree/ValueAccessor.h>
namespace openvdb {
OPENVDB_USE_VERSION_NAMESPACE
namespace OPENVDB_VERSION_NAME {
namespace tools {
// The following samplers operate in voxel space.
// When the samplers are applied to grids holding vector or other non-scalar data,
// the data is assumed to be collocated. For example, using the BoxSampler on a grid
// with ValueType Vec3f assumes that all three elements in a vector can be assigned
// the same physical location.
struct PointSampler
{
static const char* name() { return "point"; }
static int radius() { return 0; }
static bool mipmap() { return false; }
static bool consistent() { return true; }
/// @brief Sample @a inTree at the nearest neighbor to @a inCoord
/// and store the result in @a result.
/// @return @c true if the sampled value is active.
template<class TreeT>
static bool sample(const TreeT& inTree, const Vec3R& inCoord,
typename TreeT::ValueType& result);
};
struct BoxSampler
{
static const char* name() { return "box"; }
static int radius() { return 1; }
static bool mipmap() { return true; }
static bool consistent() { return true; }
/// @brief Trilinearly reconstruct @a inTree at @a inCoord
/// and store the result in @a result.
/// @return @c true if any one of the sampled values is active.
template<class TreeT>
static bool sample(const TreeT& inTree, const Vec3R& inCoord,
typename TreeT::ValueType& result);
/// @brief Trilinearly reconstruct @a inTree at @a inCoord.
/// @return the reconstructed value
template<class TreeT>
static typename TreeT::ValueType sample(const TreeT& inTree, const Vec3R& inCoord);
private:
template<class ValueT, size_t N>
static inline ValueT trilinearInterpolation(ValueT (& data)[N][N][N], const Vec3R& uvw);
};
struct QuadraticSampler
{
static const char* name() { return "quadratic"; }
static int radius() { return 1; }
static bool mipmap() { return true; }
static bool consistent() { return false; }
/// @brief Triquadratically reconstruct @a inTree at @a inCoord
/// and store the result in @a result.
/// @return @c true if any one of the sampled values is active.
template<class TreeT>
static bool sample(const TreeT& inTree, const Vec3R& inCoord,
typename TreeT::ValueType& result);
};
////////////////////////////////////////
// The following samplers operate in voxel space and are designed for Vec3
// staggered grid data (e.g., fluid simulations using the Marker-and-Cell approach
// associate elements of the velocity vector with different physical locations:
// the faces of a cube).
struct StaggeredPointSampler
{
static const char* name() { return "point"; }
static int radius() { return 0; }
static bool mipmap() { return false; }
static bool consistent() { return false; }
/// @brief Sample @a inTree at the nearest neighbor to @a inCoord
/// and store the result in @a result.
/// @return true if the sampled value is active.
template<class TreeT>
static bool sample(const TreeT& inTree, const Vec3R& inCoord,
typename TreeT::ValueType& result);
};
struct StaggeredBoxSampler
{
static const char* name() { return "box"; }
static int radius() { return 1; }
static bool mipmap() { return true; }
static bool consistent() { return false; }
/// @brief Trilinearly reconstruct @a inTree at @a inCoord
/// and store the result in @a result.
/// @return true if any one of the sampled value is active.
template<class TreeT>
static bool sample(const TreeT& inTree, const Vec3R& inCoord,
typename TreeT::ValueType& result);
};
struct StaggeredQuadraticSampler
{
static const char* name() { return "quadratic"; }
static int radius() { return 1; }
static bool mipmap() { return true; }
static bool consistent() { return false; }
/// @brief Triquadratically reconstruct @a inTree at @a inCoord
/// and store the result in @a result.
/// @return true if any one of the sampled values is active.
template<class TreeT>
static bool sample(const TreeT& inTree, const Vec3R& inCoord,
typename TreeT::ValueType& result);
};
////////////////////////////////////////
/// @brief Class that provides the interface for continuous sampling
/// of values in a tree. Consider using the GridSampler below instead.
///
/// @details Since trees support only discrete voxel sampling, TreeSampler
/// must be used to sample arbitrary continuous points in (world or
/// index) space.
///
/// @warning This implementation of the GridSampler stores a pointer
/// to a Tree for value access. While this is thread-safe it is
/// uncached and hence slow compared to using a
/// ValueAccessor. Consequently is it normally advisable to use the
/// template specialization below that employs a
/// ValueAccessor. However case must be taken when dealing with
/// multi-threading (see warning below).
template<typename GridOrTreeType, typename SamplerType>
class GridSampler
{
public:
typedef boost::shared_ptr<GridSampler> Ptr;
typedef typename GridOrTreeType::ValueType ValueType;
typedef typename TreeAdapter<GridOrTreeType>::GridType GridType;
typedef typename TreeAdapter<GridOrTreeType>::TreeType TreeType;
typedef typename TreeAdapter<GridOrTreeType>::AccessorType AccessorType;
/// @param grid a grid to be sampled
explicit GridSampler(const GridType& grid)
: mTree(&(grid.tree())), mTransform(&(grid.transform())) {}
/// @param tree a tree to be sampled, or a ValueAccessor for the tree
/// @param transform is used when sampling world space locations.
GridSampler(const TreeType& tree, const math::Transform& transform)
: mTree(&tree), mTransform(&transform) {}
const math::Transform& transform() const { return *mTransform; }
/// @brief Sample a point in index space in the grid.
/// @param x Fractional x-coordinate of point in index-coordinates of grid
/// @param y Fractional y-coordinate of point in index-coordinates of grid
/// @param z Fractional z-coordinate of point in index-coordinates of grid
template<typename RealType>
ValueType sampleVoxel(const RealType& x, const RealType& y, const RealType& z) const
{
return this->isSample(Vec3d(x,y,z));
}
/// @brief Sample value in integer index space
/// @param i Integer x-coordinate in index space
/// @param j Integer y-coordinate in index space
/// @param k Integer x-coordinate in index space
ValueType sampleVoxel(typename Coord::ValueType i,
typename Coord::ValueType j,
typename Coord::ValueType k) const
{
return this->isSample(Coord(i,j,k));
}
/// @brief Sample value in integer index space
/// @param ijk the location in index space
ValueType isSample(const Coord& ijk) const { return mTree->getValue(ijk); }
/// @brief Sample in fractional index space
/// @param ispoint the location in index space
ValueType isSample(const Vec3d& ispoint) const
{
ValueType result = zeroVal<ValueType>();
SamplerType::sample(*mTree, ispoint, result);
return result;
}
/// @brief Sample in world space
/// @param wspoint the location in world space
ValueType wsSample(const Vec3d& wspoint) const
{
ValueType result = zeroVal<ValueType>();
SamplerType::sample(*mTree, mTransform->worldToIndex(wspoint), result);
return result;
}
private:
const TreeType* mTree;
const math::Transform* mTransform;
}; // class GridSampler
/// @brief Specialization of GridSampler for construction from a ValueAccessor type
///
/// @note This version should normally be favoured over the one above
/// that takes a Grid or Tree. The reason is this version uses a
/// ValueAccessor that performs fast (cached) access where the
/// tree-based flavour performs slower (uncached) access.
///
/// @warning Since this version stores a pointer to an (externally
/// allocated) value accessor it is not threadsafe. Hence each thread
/// should have it own instance of a GridSampler constructed from a
/// local ValueAccessor. Alternatively the Grid/Tree-based GridSampler
/// is threadsafe, but also slower.
template<typename TreeT, typename SamplerType>
class GridSampler<tree::ValueAccessor<TreeT>, SamplerType>
{
public:
typedef boost::shared_ptr<GridSampler> Ptr;
typedef typename TreeT::ValueType ValueType;
typedef TreeT TreeType;
typedef Grid<TreeType> GridType;
typedef typename tree::ValueAccessor<TreeT> AccessorType;
/// @param acc a ValueAccessor to be sampled
/// @param transform is used when sampling world space locations.
GridSampler(const AccessorType& acc, const math::Transform& transform)
: mAccessor(&acc), mTransform(&transform) {}
const math::Transform& transform() const { return *mTransform; }
/// @brief Sample a point in index space in the grid.
/// @param x Fractional x-coordinate of point in index-coordinates of grid
/// @param y Fractional y-coordinate of point in index-coordinates of grid
/// @param z Fractional z-coordinate of point in index-coordinates of grid
template<typename RealType>
ValueType sampleVoxel(const RealType& x, const RealType& y, const RealType& z) const
{
return this->isSample(Vec3d(x,y,z));
}
/// @brief Sample value in integer index space
/// @param i Integer x-coordinate in index space
/// @param j Integer y-coordinate in index space
/// @param k Integer x-coordinate in index space
ValueType sampleVoxel(typename Coord::ValueType i,
typename Coord::ValueType j,
typename Coord::ValueType k) const
{
return this->isSample(Coord(i,j,k));
}
/// @brief Sample value in integer index space
/// @param ijk the location in index space
ValueType isSample(const Coord& ijk) const { return mAccessor->getValue(ijk); }
/// @brief Sample in fractional index space
/// @param ispoint the location in index space
ValueType isSample(const Vec3d& ispoint) const
{
ValueType result = zeroVal<ValueType>();
SamplerType::sample(*mAccessor, ispoint, result);
return result;
}
/// @brief Sample in world space
/// @param wspoint the location in world space
ValueType wsSample(const Vec3d& wspoint) const
{
ValueType result = zeroVal<ValueType>();
SamplerType::sample(*mAccessor, mTransform->worldToIndex(wspoint), result);
return result;
}
private:
const AccessorType* mAccessor;//not thread-safe!
const math::Transform* mTransform;
};//Specialization of GridSampler
////////////////////////////////////////
/// @brief This is a simple convenience class that allows for sampling
/// from a source grid into the index space of a target grid. At
/// construction the source and target grids are checked for alignment
/// which potentially renders interpolation unnecessary. Else
/// interpolation is performed according to the templated Sampler type.
///
/// @warning For performance reasons the check for alignment of the
/// two grids is only performed at construction time! Also note that
/// unless the grids are aligned, virtual methods are used to resolve
/// the coordinate transformations, which is clearly not optimal. So
/// consider resolving the Map types of the two grids for better
/// performance.
template<typename SourceGridT,
typename TargetGridT,
typename SamplerT = tools::BoxSampler>
class DualGridSampler
{
public:
typedef typename SourceGridT::ValueType ValueType;
DualGridSampler(const SourceGridT& source, const TargetGridT& target)
: mTarget(&target), mSource(&source), mAccessor(source.tree()),
mAligned(target.transform() == source.transform())
{
}
/// @brief Return the value of the source grid at the index
/// coordinates, ijk, relative to the target grid.
inline ValueType operator()(const Coord& ijk) const
{
return mAligned ? mAccessor.getValue(ijk) : SamplerT::sample(mAccessor,
mSource->worldToIndex(mTarget->indexToWorld(ijk)));
}
private:
const TargetGridT* mTarget;
const SourceGridT* mSource;
typename SourceGridT::ConstAccessor mAccessor;
const bool mAligned;
};// DualGridSampler
////////////////////////////////////////
namespace local_util {
inline Vec3i
floorVec3(const Vec3R& v)
{
return Vec3i(int(std::floor(v(0))), int(std::floor(v(1))), int(std::floor(v(2))));
}
inline Vec3i
ceilVec3(const Vec3R& v)
{
return Vec3i(int(std::ceil(v(0))), int(std::ceil(v(1))), int(std::ceil(v(2))));
}
inline Vec3i
roundVec3(const Vec3R& v)
{
return Vec3i(int(::round(v(0))), int(::round(v(1))), int(::round(v(2))));
}
} // namespace local_util
////////////////////////////////////////
template<class TreeT>
inline bool
PointSampler::sample(const TreeT& inTree, const Vec3R& inCoord,
typename TreeT::ValueType& result)
{
Vec3i inIdx = local_util::roundVec3(inCoord);
return inTree.probeValue(Coord(inIdx), result);
}
////////////////////////////////////////
template<class ValueT, size_t N>
inline ValueT
BoxSampler::trilinearInterpolation(ValueT (& data)[N][N][N], const Vec3R& uvw)
{
// Trilinear interpolation:
// The eight surrounding latice values are used to construct the result. \n
// result(x,y,z) =
// v000 (1-x)(1-y)(1-z) + v001 (1-x)(1-y)z + v010 (1-x)y(1-z) + v011 (1-x)yz
// + v100 x(1-y)(1-z) + v101 x(1-y)z + v110 xy(1-z) + v111 xyz
ValueT resultA, resultB;
resultA = data[0][0][0] + ValueT((data[0][0][1] - data[0][0][0]) * uvw[2]);
resultB = data[0][1][0] + ValueT((data[0][1][1] - data[0][1][0]) * uvw[2]);
ValueT result1 = resultA + ValueT((resultB-resultA) * uvw[1]);
resultA = data[1][0][0] + ValueT((data[1][0][1] - data[1][0][0]) * uvw[2]);
resultB = data[1][1][0] + ValueT((data[1][1][1] - data[1][1][0]) * uvw[2]);
ValueT result2 = resultA + ValueT((resultB - resultA) * uvw[1]);
return result1 + ValueT(uvw[0] * (result2 - result1));
}
template<class TreeT>
inline bool
BoxSampler::sample(const TreeT& inTree, const Vec3R& inCoord,
typename TreeT::ValueType& result)
{
typedef typename TreeT::ValueType ValueT;
Vec3i inIdx = local_util::floorVec3(inCoord);
Vec3R uvw = inCoord - inIdx;
// Retrieve the values of the eight voxels surrounding the
// fractional source coordinates.
ValueT data[2][2][2];
bool hasActiveValues = false;
Coord ijk(inIdx);
hasActiveValues |= inTree.probeValue(ijk, data[0][0][0]); // i, j, k
ijk[2] += 1;
hasActiveValues |= inTree.probeValue(ijk, data[0][0][1]); // i, j, k + 1
ijk[1] += 1;
hasActiveValues |= inTree.probeValue(ijk, data[0][1][1]); // i, j+1, k + 1
ijk[2] = inIdx[2];
hasActiveValues |= inTree.probeValue(ijk, data[0][1][0]); // i, j+1, k
ijk[0] += 1;
ijk[1] = inIdx[1];
hasActiveValues |= inTree.probeValue(ijk, data[1][0][0]); // i+1, j, k
ijk[2] += 1;
hasActiveValues |= inTree.probeValue(ijk, data[1][0][1]); // i+1, j, k + 1
ijk[1] += 1;
hasActiveValues |= inTree.probeValue(ijk, data[1][1][1]); // i+1, j+1, k + 1
ijk[2] = inIdx[2];
hasActiveValues |= inTree.probeValue(ijk, data[1][1][0]); // i+1, j+1, k
result = trilinearInterpolation(data, uvw);
return hasActiveValues;
}
template<class TreeT>
inline typename TreeT::ValueType
BoxSampler::sample(const TreeT& inTree, const Vec3R& inCoord)
{
typedef typename TreeT::ValueType ValueT;
Vec3i inIdx = local_util::floorVec3(inCoord);
Vec3R uvw = inCoord - inIdx;
// Retrieve the values of the eight voxels surrounding the
// fractional source coordinates.
ValueT data[2][2][2];
Coord ijk(inIdx);
data[0][0][0] = inTree.getValue(ijk); // i, j, k
ijk[2] += 1;
data[0][0][1] = inTree.getValue(ijk); // i, j, k + 1
ijk[1] += 1;
data[0][1][1] = inTree.getValue(ijk); // i, j+1, k + 1
ijk[2] = inIdx[2];
data[0][1][0] = inTree.getValue(ijk); // i, j+1, k
ijk[0] += 1;
ijk[1] = inIdx[1];
data[1][0][0] = inTree.getValue(ijk); // i+1, j, k
ijk[2] += 1;
data[1][0][1] = inTree.getValue(ijk); // i+1, j, k + 1
ijk[1] += 1;
data[1][1][1] = inTree.getValue(ijk); // i+1, j+1, k + 1
ijk[2] = inIdx[2];
data[1][1][0] = inTree.getValue(ijk); // i+1, j+1, k
return trilinearInterpolation(data, uvw);
}
////////////////////////////////////////
template<class TreeT>
inline bool
QuadraticSampler::sample(const TreeT& inTree, const Vec3R& inCoord,
typename TreeT::ValueType& result)
{
typedef typename TreeT::ValueType ValueT;
Vec3i
inIdx = local_util::floorVec3(inCoord),
inLoIdx = inIdx - Vec3i(1, 1, 1);
Vec3R frac = inCoord - inIdx;
// Retrieve the values of the 27 voxels surrounding the
// fractional source coordinates.
bool active = false;
ValueT v[3][3][3];
for (int dx = 0, ix = inLoIdx.x(); dx < 3; ++dx, ++ix) {
for (int dy = 0, iy = inLoIdx.y(); dy < 3; ++dy, ++iy) {
for (int dz = 0, iz = inLoIdx.z(); dz < 3; ++dz, ++iz) {
if (inTree.probeValue(Coord(ix, iy, iz), v[dx][dy][dz])) {
active = true;
}
}
}
}
/// @todo For vector types, interpolate over each component independently.
ValueT vx[3];
for (int dx = 0; dx < 3; ++dx) {
ValueT vy[3];
for (int dy = 0; dy < 3; ++dy) {
// Fit a parabola to three contiguous samples in z
// (at z=-1, z=0 and z=1), then evaluate the parabola at z',
// where z' is the fractional part of inCoord.z, i.e.,
// inCoord.z - inIdx.z. The coefficients come from solving
//
// | (-1)^2 -1 1 || a | | v0 |
// | 0 0 1 || b | = | v1 |
// | 1^2 1 1 || c | | v2 |
//
// for a, b and c.
const ValueT* vz = &v[dx][dy][0];
const ValueT
az = static_cast<ValueT>(0.5 * (vz[0] + vz[2]) - vz[1]),
bz = static_cast<ValueT>(0.5 * (vz[2] - vz[0])),
cz = static_cast<ValueT>(vz[1]);
vy[dy] = static_cast<ValueT>(frac.z() * (frac.z() * az + bz) + cz);
}
// Fit a parabola to three interpolated samples in y, then
// evaluate the parabola at y', where y' is the fractional
// part of inCoord.y.
const ValueT
ay = static_cast<ValueT>(0.5 * (vy[0] + vy[2]) - vy[1]),
by = static_cast<ValueT>(0.5 * (vy[2] - vy[0])),
cy = static_cast<ValueT>(vy[1]);
vx[dx] = static_cast<ValueT>(frac.y() * (frac.y() * ay + by) + cy);
}
// Fit a parabola to three interpolated samples in x, then
// evaluate the parabola at the fractional part of inCoord.x.
const ValueT
ax = static_cast<ValueT>(0.5 * (vx[0] + vx[2]) - vx[1]),
bx = static_cast<ValueT>(0.5 * (vx[2] - vx[0])),
cx = static_cast<ValueT>(vx[1]);
result = static_cast<ValueT>(frac.x() * (frac.x() * ax + bx) + cx);
return active;
}
////////////////////////////////////////
template<class TreeT>
inline bool
StaggeredPointSampler::sample(const TreeT& inTree, const Vec3R& inCoord,
typename TreeT::ValueType& result)
{
typedef typename TreeT::ValueType ValueType;
ValueType tempX, tempY, tempZ;
bool active = false;
active = PointSampler::sample<TreeT>(inTree, inCoord + Vec3R(0.5, 0, 0), tempX) || active;
active = PointSampler::sample<TreeT>(inTree, inCoord + Vec3R(0, 0.5, 0), tempY) || active;
active = PointSampler::sample<TreeT>(inTree, inCoord + Vec3R(0, 0, 0.5), tempZ) || active;
result.x() = tempX.x();
result.y() = tempY.y();
result.z() = tempZ.z();
return active;
}
////////////////////////////////////////
template<class TreeT>
inline bool
StaggeredBoxSampler::sample(const TreeT& inTree, const Vec3R& inCoord,
typename TreeT::ValueType& result)
{
typedef typename TreeT::ValueType ValueType;
ValueType tempX, tempY, tempZ;
tempX = tempY = tempZ = zeroVal<ValueType>();
bool active = false;
active = BoxSampler::sample<TreeT>(inTree, inCoord + Vec3R(0.5, 0, 0), tempX) || active;
active = BoxSampler::sample<TreeT>(inTree, inCoord + Vec3R(0, 0.5, 0), tempY) || active;
active = BoxSampler::sample<TreeT>(inTree, inCoord + Vec3R(0, 0, 0.5), tempZ) || active;
result.x() = tempX.x();
result.y() = tempY.y();
result.z() = tempZ.z();
return active;
}
////////////////////////////////////////
template<class TreeT>
inline bool
StaggeredQuadraticSampler::sample(const TreeT& inTree, const Vec3R& inCoord,
typename TreeT::ValueType& result)
{
typedef typename TreeT::ValueType ValueType;
ValueType tempX, tempY, tempZ;
bool active = false;
active = QuadraticSampler::sample<TreeT>(inTree, inCoord + Vec3R(0.5, 0, 0), tempX) || active;
active = QuadraticSampler::sample<TreeT>(inTree, inCoord + Vec3R(0, 0.5, 0), tempY) || active;
active = QuadraticSampler::sample<TreeT>(inTree, inCoord + Vec3R(0, 0, 0.5), tempZ) || active;
result.x() = tempX.x();
result.y() = tempY.y();
result.z() = tempZ.z();
return active;
}
} // namespace tools
} // namespace OPENVDB_VERSION_NAME
} // namespace openvdb
#endif // OPENVDB_TOOLS_INTERPOLATION_HAS_BEEN_INCLUDED
// Copyright (c) 2012-2013 DreamWorks Animation LLC
// All rights reserved. This software is distributed under the
// Mozilla Public License 2.0 ( http://www.mozilla.org/MPL/2.0/ )
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