vtk-m/vtkm/exec/ParametricCoordinates.h
David Thompson 00c7905afb Rename vtkm::dot() to vtkm::Dot().
This keeps the old name around but prepares it for removal
in the next release.
2018-05-17 08:51:01 -04:00

1118 lines
42 KiB
C++

//============================================================================
// Copyright (c) Kitware, Inc.
// All rights reserved.
// See LICENSE.txt for details.
// This software is distributed WITHOUT ANY WARRANTY; without even
// the implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR
// PURPOSE. See the above copyright notice for more information.
//
// Copyright 2015 National Technology & Engineering Solutions of Sandia, LLC (NTESS).
// Copyright 2015 UT-Battelle, LLC.
// Copyright 2015 Los Alamos National Security.
//
// Under the terms of Contract DE-NA0003525 with NTESS,
// the U.S. Government retains certain rights in this software.
//
// Under the terms of Contract DE-AC52-06NA25396 with Los Alamos National
// Laboratory (LANL), the U.S. Government retains certain rights in
// this software.
//============================================================================
#ifndef vtk_m_exec_ParametricCoordinates_h
#define vtk_m_exec_ParametricCoordinates_h
#include <vtkm/Assert.h>
#include <vtkm/CellShape.h>
#include <vtkm/Math.h>
#include <vtkm/NewtonsMethod.h>
#include <vtkm/VecAxisAlignedPointCoordinates.h>
#include <vtkm/exec/CellInterpolate.h>
#include <vtkm/exec/FunctorBase.h>
#include <vtkm/exec/Jacobian.h>
#include <vtkm/exec/internal/FastVec.h>
#include <vtkm/internal/Assume.h>
namespace vtkm
{
namespace exec
{
//-----------------------------------------------------------------------------
template <typename ParametricCoordType>
static inline VTKM_EXEC void ParametricCoordinatesCenter(vtkm::IdComponent numPoints,
vtkm::Vec<ParametricCoordType, 3>& pcoords,
vtkm::CellShapeTagEmpty,
const vtkm::exec::FunctorBase&)
{
(void)numPoints; // Silence compiler warnings.
VTKM_ASSERT(numPoints == 0);
pcoords[0] = 0;
pcoords[1] = 0;
pcoords[2] = 0;
}
template <typename ParametricCoordType>
static inline VTKM_EXEC void ParametricCoordinatesCenter(vtkm::IdComponent numPoints,
vtkm::Vec<ParametricCoordType, 3>& pcoords,
vtkm::CellShapeTagVertex,
const vtkm::exec::FunctorBase&)
{
(void)numPoints; // Silence compiler warnings.
VTKM_ASSERT(numPoints == 1);
pcoords[0] = 0;
pcoords[1] = 0;
pcoords[2] = 0;
}
template <typename ParametricCoordType>
static inline VTKM_EXEC void ParametricCoordinatesCenter(vtkm::IdComponent numPoints,
vtkm::Vec<ParametricCoordType, 3>& pcoords,
vtkm::CellShapeTagLine,
const vtkm::exec::FunctorBase&)
{
(void)numPoints; // Silence compiler warnings.
VTKM_ASSERT(numPoints == 2);
pcoords[0] = 0.5;
pcoords[1] = 0;
pcoords[2] = 0;
}
template <typename ParametricCoordType>
static inline VTKM_EXEC void ParametricCoordinatesCenter(vtkm::IdComponent numPoints,
vtkm::Vec<ParametricCoordType, 3>& pcoords,
vtkm::CellShapeTagTriangle,
const vtkm::exec::FunctorBase&)
{
(void)numPoints; // Silence compiler warnings.
VTKM_ASSERT(numPoints == 3);
pcoords[0] = static_cast<ParametricCoordType>(1.0 / 3.0);
pcoords[1] = static_cast<ParametricCoordType>(1.0 / 3.0);
pcoords[2] = 0;
}
template <typename ParametricCoordType>
static inline VTKM_EXEC void ParametricCoordinatesCenter(vtkm::IdComponent numPoints,
vtkm::Vec<ParametricCoordType, 3>& pcoords,
vtkm::CellShapeTagPolygon,
const vtkm::exec::FunctorBase& worklet)
{
VTKM_ASSERT(numPoints > 0);
switch (numPoints)
{
case 1:
ParametricCoordinatesCenter(numPoints, pcoords, vtkm::CellShapeTagVertex(), worklet);
break;
case 2:
ParametricCoordinatesCenter(numPoints, pcoords, vtkm::CellShapeTagLine(), worklet);
break;
case 3:
ParametricCoordinatesCenter(numPoints, pcoords, vtkm::CellShapeTagTriangle(), worklet);
break;
default:
pcoords[0] = 0.5;
pcoords[1] = 0.5;
pcoords[2] = 0;
break;
}
}
template <typename ParametricCoordType>
static inline VTKM_EXEC void ParametricCoordinatesCenter(vtkm::IdComponent numPoints,
vtkm::Vec<ParametricCoordType, 3>& pcoords,
vtkm::CellShapeTagQuad,
const vtkm::exec::FunctorBase&)
{
(void)numPoints; // Silence compiler warnings.
VTKM_ASSERT(numPoints == 4);
pcoords[0] = 0.5;
pcoords[1] = 0.5;
pcoords[2] = 0;
}
template <typename ParametricCoordType>
static inline VTKM_EXEC void ParametricCoordinatesCenter(vtkm::IdComponent numPoints,
vtkm::Vec<ParametricCoordType, 3>& pcoords,
vtkm::CellShapeTagTetra,
const vtkm::exec::FunctorBase&)
{
(void)numPoints; // Silence compiler warnings.
VTKM_ASSERT(numPoints == 4);
pcoords[0] = 0.25;
pcoords[1] = 0.25;
pcoords[2] = 0.25;
}
template <typename ParametricCoordType>
static inline VTKM_EXEC void ParametricCoordinatesCenter(vtkm::IdComponent numPoints,
vtkm::Vec<ParametricCoordType, 3>& pcoords,
vtkm::CellShapeTagHexahedron,
const vtkm::exec::FunctorBase&)
{
(void)numPoints; // Silence compiler warnings.
VTKM_ASSERT(numPoints == 8);
pcoords[0] = 0.5;
pcoords[1] = 0.5;
pcoords[2] = 0.5;
}
template <typename ParametricCoordType>
static inline VTKM_EXEC void ParametricCoordinatesCenter(vtkm::IdComponent numPoints,
vtkm::Vec<ParametricCoordType, 3>& pcoords,
vtkm::CellShapeTagWedge,
const vtkm::exec::FunctorBase&)
{
(void)numPoints; // Silence compiler warnings.
VTKM_ASSERT(numPoints == 6);
pcoords[0] = static_cast<ParametricCoordType>(1.0 / 3.0);
pcoords[1] = static_cast<ParametricCoordType>(1.0 / 3.0);
pcoords[2] = 0.5;
}
template <typename ParametricCoordType>
static inline VTKM_EXEC void ParametricCoordinatesCenter(vtkm::IdComponent numPoints,
vtkm::Vec<ParametricCoordType, 3>& pcoords,
vtkm::CellShapeTagPyramid,
const vtkm::exec::FunctorBase&)
{
(void)numPoints; // Silence compiler warnings.
VTKM_ASSERT(numPoints == 5);
pcoords[0] = 0.5;
pcoords[1] = 0.5;
pcoords[2] = static_cast<ParametricCoordType>(0.2);
}
//-----------------------------------------------------------------------------
/// Returns the parametric center of the given cell shape with the given number
/// of points.
///
template <typename ParametricCoordType>
static inline VTKM_EXEC void ParametricCoordinatesCenter(vtkm::IdComponent numPoints,
vtkm::Vec<ParametricCoordType, 3>& pcoords,
vtkm::CellShapeTagGeneric shape,
const vtkm::exec::FunctorBase& worklet)
{
switch (shape.Id)
{
vtkmGenericCellShapeMacro(
ParametricCoordinatesCenter(numPoints, pcoords, CellShapeTag(), worklet));
default:
worklet.RaiseError("Bad shape given to ParametricCoordinatesCenter.");
pcoords[0] = pcoords[1] = pcoords[2] = 0;
break;
}
}
/// Returns the parametric center of the given cell shape with the given number
/// of points.
///
template <typename CellShapeTag>
static inline VTKM_EXEC vtkm::Vec<vtkm::FloatDefault, 3> ParametricCoordinatesCenter(
vtkm::IdComponent numPoints,
CellShapeTag shape,
const vtkm::exec::FunctorBase& worklet)
{
vtkm::Vec<vtkm::FloatDefault, 3> pcoords;
ParametricCoordinatesCenter(numPoints, pcoords, shape, worklet);
return pcoords;
}
//-----------------------------------------------------------------------------
template <typename ParametricCoordType>
static inline VTKM_EXEC void ParametricCoordinatesPoint(vtkm::IdComponent,
vtkm::IdComponent,
vtkm::Vec<ParametricCoordType, 3>& pcoords,
vtkm::CellShapeTagEmpty,
const vtkm::exec::FunctorBase& worklet)
{
worklet.RaiseError("Empty cell has no points.");
pcoords[0] = pcoords[1] = pcoords[2] = 0;
}
template <typename ParametricCoordType>
static inline VTKM_EXEC void ParametricCoordinatesPoint(vtkm::IdComponent numPoints,
vtkm::IdComponent pointIndex,
vtkm::Vec<ParametricCoordType, 3>& pcoords,
vtkm::CellShapeTagVertex,
const vtkm::exec::FunctorBase&)
{
(void)numPoints; // Silence compiler warnings.
(void)pointIndex; // Silence compiler warnings.
VTKM_ASSUME(numPoints == 1);
VTKM_ASSUME(pointIndex == 0);
pcoords[0] = 0;
pcoords[1] = 0;
pcoords[2] = 0;
}
template <typename ParametricCoordType>
static inline VTKM_EXEC void ParametricCoordinatesPoint(vtkm::IdComponent numPoints,
vtkm::IdComponent pointIndex,
vtkm::Vec<ParametricCoordType, 3>& pcoords,
vtkm::CellShapeTagLine,
const vtkm::exec::FunctorBase&)
{
(void)numPoints; // Silence compiler warnings.
VTKM_ASSUME(numPoints == 2);
VTKM_ASSUME((pointIndex >= 0) && (pointIndex < 2));
pcoords[0] = static_cast<ParametricCoordType>(pointIndex);
pcoords[1] = 0;
pcoords[2] = 0;
}
template <typename ParametricCoordType>
static inline VTKM_EXEC void ParametricCoordinatesPoint(vtkm::IdComponent numPoints,
vtkm::IdComponent pointIndex,
vtkm::Vec<ParametricCoordType, 3>& pcoords,
vtkm::CellShapeTagTriangle,
const vtkm::exec::FunctorBase&)
{
(void)numPoints; // Silence compiler warnings.
VTKM_ASSUME(numPoints == 3);
VTKM_ASSUME((pointIndex >= 0) && (pointIndex < 3));
switch (pointIndex)
{
case 0:
pcoords[0] = 0;
pcoords[1] = 0;
break;
case 1:
pcoords[0] = 1;
pcoords[1] = 0;
break;
case 2:
pcoords[0] = 0;
pcoords[1] = 1;
break;
}
pcoords[2] = 0;
}
template <typename ParametricCoordType>
static inline VTKM_EXEC void ParametricCoordinatesPoint(vtkm::IdComponent numPoints,
vtkm::IdComponent pointIndex,
vtkm::Vec<ParametricCoordType, 3>& pcoords,
vtkm::CellShapeTagPolygon,
const vtkm::exec::FunctorBase& worklet)
{
VTKM_ASSUME((numPoints > 0));
VTKM_ASSUME((pointIndex >= 0) && (pointIndex < numPoints));
switch (numPoints)
{
case 1:
ParametricCoordinatesPoint(
numPoints, pointIndex, pcoords, vtkm::CellShapeTagVertex(), worklet);
return;
case 2:
ParametricCoordinatesPoint(numPoints, pointIndex, pcoords, vtkm::CellShapeTagLine(), worklet);
return;
case 3:
ParametricCoordinatesPoint(
numPoints, pointIndex, pcoords, vtkm::CellShapeTagTriangle(), worklet);
return;
case 4:
ParametricCoordinatesPoint(numPoints, pointIndex, pcoords, vtkm::CellShapeTagQuad(), worklet);
return;
}
// If we are here, then numPoints >= 5.
const ParametricCoordType angle =
static_cast<ParametricCoordType>(pointIndex * 2 * vtkm::Pi() / numPoints);
pcoords[0] = 0.5f * (vtkm::Cos(angle) + 1);
pcoords[1] = 0.5f * (vtkm::Sin(angle) + 1);
pcoords[2] = 0;
}
template <typename ParametricCoordType>
static inline VTKM_EXEC void ParametricCoordinatesPoint(vtkm::IdComponent numPoints,
vtkm::IdComponent pointIndex,
vtkm::Vec<ParametricCoordType, 3>& pcoords,
vtkm::CellShapeTagQuad,
const vtkm::exec::FunctorBase&)
{
(void)numPoints; // Silence compiler warnings.
VTKM_ASSUME(numPoints == 4);
VTKM_ASSUME((pointIndex >= 0) && (pointIndex < 4));
switch (pointIndex)
{
case 0:
pcoords[0] = 0;
pcoords[1] = 0;
break;
case 1:
pcoords[0] = 1;
pcoords[1] = 0;
break;
case 2:
pcoords[0] = 1;
pcoords[1] = 1;
break;
case 3:
pcoords[0] = 0;
pcoords[1] = 1;
break;
}
pcoords[2] = 0;
}
template <typename ParametricCoordType>
static inline VTKM_EXEC void ParametricCoordinatesPoint(vtkm::IdComponent numPoints,
vtkm::IdComponent pointIndex,
vtkm::Vec<ParametricCoordType, 3>& pcoords,
vtkm::CellShapeTagTetra,
const vtkm::exec::FunctorBase&)
{
(void)numPoints; // Silence compiler warnings.
VTKM_ASSUME(numPoints == 4);
VTKM_ASSUME((pointIndex >= 0) && (pointIndex < 4));
switch (pointIndex)
{
case 0:
pcoords[0] = 0;
pcoords[1] = 0;
pcoords[2] = 0;
break;
case 1:
pcoords[0] = 1;
pcoords[1] = 0;
pcoords[2] = 0;
break;
case 2:
pcoords[0] = 0;
pcoords[1] = 1;
pcoords[2] = 0;
break;
case 3:
pcoords[0] = 0;
pcoords[1] = 0;
pcoords[2] = 1;
break;
}
}
template <typename ParametricCoordType>
static inline VTKM_EXEC void ParametricCoordinatesPoint(vtkm::IdComponent numPoints,
vtkm::IdComponent pointIndex,
vtkm::Vec<ParametricCoordType, 3>& pcoords,
vtkm::CellShapeTagHexahedron,
const vtkm::exec::FunctorBase&)
{
(void)numPoints; // Silence compiler warnings.
VTKM_ASSUME(numPoints == 8);
VTKM_ASSUME((pointIndex >= 0) && (pointIndex < 8));
switch (pointIndex)
{
case 0:
pcoords[0] = 0;
pcoords[1] = 0;
pcoords[2] = 0;
break;
case 1:
pcoords[0] = 1;
pcoords[1] = 0;
pcoords[2] = 0;
break;
case 2:
pcoords[0] = 1;
pcoords[1] = 1;
pcoords[2] = 0;
break;
case 3:
pcoords[0] = 0;
pcoords[1] = 1;
pcoords[2] = 0;
break;
case 4:
pcoords[0] = 0;
pcoords[1] = 0;
pcoords[2] = 1;
break;
case 5:
pcoords[0] = 1;
pcoords[1] = 0;
pcoords[2] = 1;
break;
case 6:
pcoords[0] = 1;
pcoords[1] = 1;
pcoords[2] = 1;
break;
case 7:
pcoords[0] = 0;
pcoords[1] = 1;
pcoords[2] = 1;
break;
}
}
template <typename ParametricCoordType>
static inline VTKM_EXEC void ParametricCoordinatesPoint(vtkm::IdComponent numPoints,
vtkm::IdComponent pointIndex,
vtkm::Vec<ParametricCoordType, 3>& pcoords,
vtkm::CellShapeTagWedge,
const vtkm::exec::FunctorBase&)
{
(void)numPoints; // Silence compiler warnings.
VTKM_ASSUME(numPoints == 6);
VTKM_ASSUME((pointIndex >= 0) && (pointIndex < 6));
switch (pointIndex)
{
case 0:
pcoords[0] = 0;
pcoords[1] = 0;
pcoords[2] = 0;
break;
case 1:
pcoords[0] = 0;
pcoords[1] = 1;
pcoords[2] = 0;
break;
case 2:
pcoords[0] = 1;
pcoords[1] = 0;
pcoords[2] = 0;
break;
case 3:
pcoords[0] = 0;
pcoords[1] = 0;
pcoords[2] = 1;
break;
case 4:
pcoords[0] = 0;
pcoords[1] = 1;
pcoords[2] = 1;
break;
case 5:
pcoords[0] = 1;
pcoords[1] = 0;
pcoords[2] = 1;
break;
}
}
template <typename ParametricCoordType>
static inline VTKM_EXEC void ParametricCoordinatesPoint(vtkm::IdComponent numPoints,
vtkm::IdComponent pointIndex,
vtkm::Vec<ParametricCoordType, 3>& pcoords,
vtkm::CellShapeTagPyramid,
const vtkm::exec::FunctorBase&)
{
(void)numPoints; // Silence compiler warnings.
VTKM_ASSUME(numPoints == 5);
VTKM_ASSUME((pointIndex >= 0) && (pointIndex < 5));
switch (pointIndex)
{
case 0:
pcoords[0] = 0;
pcoords[1] = 0;
pcoords[2] = 0;
break;
case 1:
pcoords[0] = 1;
pcoords[1] = 0;
pcoords[2] = 0;
break;
case 2:
pcoords[0] = 1;
pcoords[1] = 1;
pcoords[2] = 0;
break;
case 3:
pcoords[0] = 0;
pcoords[1] = 1;
pcoords[2] = 0;
break;
case 4:
pcoords[0] = 0.5;
pcoords[1] = 0.5;
pcoords[2] = 1;
break;
}
}
//-----------------------------------------------------------------------------
/// Returns the parametric coordinate of a cell point of the given shape with
/// the given number of points.
///
template <typename ParametricCoordType>
static inline VTKM_EXEC void ParametricCoordinatesPoint(vtkm::IdComponent numPoints,
vtkm::IdComponent pointIndex,
vtkm::Vec<ParametricCoordType, 3>& pcoords,
vtkm::CellShapeTagGeneric shape,
const vtkm::exec::FunctorBase& worklet)
{
switch (shape.Id)
{
vtkmGenericCellShapeMacro(
ParametricCoordinatesPoint(numPoints, pointIndex, pcoords, CellShapeTag(), worklet));
default:
worklet.RaiseError("Bad shape given to ParametricCoordinatesPoint.");
pcoords[0] = pcoords[1] = pcoords[2] = 0;
break;
}
}
/// Returns the parametric coordinate of a cell point of the given shape with
/// the given number of points.
///
template <typename CellShapeTag>
static inline VTKM_EXEC vtkm::Vec<vtkm::FloatDefault, 3> ParametricCoordinatesPoint(
vtkm::IdComponent numPoints,
vtkm::IdComponent pointIndex,
CellShapeTag shape,
const vtkm::exec::FunctorBase& worklet)
{
vtkm::Vec<vtkm::FloatDefault, 3> pcoords;
ParametricCoordinatesPoint(numPoints, pointIndex, pcoords, shape, worklet);
return pcoords;
}
//-----------------------------------------------------------------------------
template <typename WorldCoordVector, typename PCoordType, typename CellShapeTag>
static inline VTKM_EXEC typename WorldCoordVector::ComponentType
ParametricCoordinatesToWorldCoordinates(const WorldCoordVector& pointWCoords,
const vtkm::Vec<PCoordType, 3>& pcoords,
CellShapeTag shape,
const vtkm::exec::FunctorBase& worklet)
{
return vtkm::exec::CellInterpolate(pointWCoords, pcoords, shape, worklet);
}
//-----------------------------------------------------------------------------
template <typename WorldCoordVector>
static inline VTKM_EXEC typename WorldCoordVector::ComponentType
WorldCoordinatesToParametricCoordinates(const WorldCoordVector&,
const typename WorldCoordVector::ComponentType&,
vtkm::CellShapeTagEmpty,
bool& success,
const vtkm::exec::FunctorBase& worklet)
{
worklet.RaiseError("Attempted to find point coordinates in empty cell.");
success = false;
return typename WorldCoordVector::ComponentType();
}
template <typename WorldCoordVector>
static inline VTKM_EXEC typename WorldCoordVector::ComponentType
WorldCoordinatesToParametricCoordinates(const WorldCoordVector& pointWCoords,
const typename WorldCoordVector::ComponentType&,
vtkm::CellShapeTagVertex,
bool& success,
const vtkm::exec::FunctorBase& vtkmNotUsed(worklet))
{
(void)pointWCoords; // Silence compiler warnings.
VTKM_ASSERT(pointWCoords.GetNumberOfComponents() == 1);
success = true;
return typename WorldCoordVector::ComponentType(0, 0, 0);
}
template <typename WorldCoordVector>
static inline VTKM_EXEC typename WorldCoordVector::ComponentType
WorldCoordinatesToParametricCoordinates(const WorldCoordVector& pointWCoords,
const typename WorldCoordVector::ComponentType& wcoords,
vtkm::CellShapeTagLine,
bool& success,
const vtkm::exec::FunctorBase& vtkmNotUsed(worklet))
{
VTKM_ASSERT(pointWCoords.GetNumberOfComponents() == 2);
success = true;
// Because this is a line, there is only one valid parametric coordinate. Let
// vec be the vector from the first point to the second point
// (pointWCoords[1] - pointWCoords[0]), which is the direction of the line.
// Dot(vec,wcoords-pointWCoords[0])/mag(vec) is the orthoginal projection of
// wcoords on the line and represents the distance between the orthoginal
// projection and pointWCoords[0]. The parametric coordinate is the fraction
// of this over the length of the segment, which is mag(vec). Thus, the
// parametric coordinate is Dot(vec,wcoords-pointWCoords[0])/mag(vec)^2.
using Vector3 = typename WorldCoordVector::ComponentType;
using T = typename Vector3::ComponentType;
Vector3 vec = pointWCoords[1] - pointWCoords[0];
T numerator = vtkm::Dot(vec, wcoords - pointWCoords[0]);
T denominator = vtkm::MagnitudeSquared(vec);
return Vector3(numerator / denominator, 0, 0);
}
template <typename WorldCoordVector>
static inline VTKM_EXEC typename WorldCoordVector::ComponentType
WorldCoordinatesToParametricCoordinates(const WorldCoordVector& pointWCoords,
const typename WorldCoordVector::ComponentType& wcoords,
vtkm::CellShapeTagTriangle,
bool& success,
const vtkm::exec::FunctorBase&)
{
success = true;
vtkm::exec::internal::FastVec<WorldCoordVector, 3> local(pointWCoords);
return vtkm::exec::internal::ReverseInterpolateTriangle(local.Get(), wcoords);
}
//-----------------------------------------------------------------------------
namespace detail
{
template <typename WorldCoordVector, typename CellShapeTag>
class JacobianFunctorQuad
{
using T = typename WorldCoordVector::ComponentType::ComponentType;
using Vector2 = vtkm::Vec<T, 2>;
using Matrix2x2 = vtkm::Matrix<T, 2, 2>;
using SpaceType = vtkm::exec::internal::Space2D<T>;
const WorldCoordVector* PointWCoords;
const SpaceType* Space;
public:
VTKM_EXEC
JacobianFunctorQuad(const WorldCoordVector* pointWCoords, const SpaceType* space)
: PointWCoords(pointWCoords)
, Space(space)
{
}
VTKM_EXEC
Matrix2x2 operator()(const Vector2& pcoords) const
{
Matrix2x2 jacobian;
vtkm::exec::JacobianFor2DCell(*this->PointWCoords,
vtkm::Vec<T, 3>(pcoords[0], pcoords[1], 0),
*this->Space,
jacobian,
CellShapeTag());
return jacobian;
}
};
template <typename WorldCoordVector, typename CellShapeTag>
class CoordinatesFunctorQuad
{
using T = typename WorldCoordVector::ComponentType::ComponentType;
using Vector2 = vtkm::Vec<T, 2>;
using Vector3 = vtkm::Vec<T, 3>;
using SpaceType = vtkm::exec::internal::Space2D<T>;
const WorldCoordVector* PointWCoords;
const SpaceType* Space;
const vtkm::exec::FunctorBase* Worklet;
public:
VTKM_EXEC
CoordinatesFunctorQuad(const WorldCoordVector* pointWCoords,
const SpaceType* space,
const vtkm::exec::FunctorBase* worklet)
: PointWCoords(pointWCoords)
, Space(space)
, Worklet(worklet)
{
}
VTKM_EXEC
Vector2 operator()(Vector2 pcoords) const
{
Vector3 pcoords3D(pcoords[0], pcoords[1], 0);
Vector3 wcoords = vtkm::exec::ParametricCoordinatesToWorldCoordinates(
*this->PointWCoords, pcoords3D, CellShapeTag(), *this->Worklet);
return this->Space->ConvertCoordToSpace(wcoords);
}
};
template <typename WorldCoordVector>
static inline VTKM_EXEC typename WorldCoordVector::ComponentType
WorldCoordinatesToParametricCoordinatesQuad(const WorldCoordVector& pointWCoords,
const typename WorldCoordVector::ComponentType& wcoords,
bool& success,
const vtkm::exec::FunctorBase& worklet)
{
using T = typename WorldCoordVector::ComponentType::ComponentType;
using Vector2 = vtkm::Vec<T, 2>;
using Vector3 = vtkm::Vec<T, 3>;
// We have an underdetermined system in 3D, so create a 2D space in the
// plane that the polygon sits.
vtkm::exec::internal::Space2D<T> space(pointWCoords[0], pointWCoords[1], pointWCoords[3]);
auto result = vtkm::NewtonsMethod(
JacobianFunctorQuad<WorldCoordVector, vtkm::CellShapeTagQuad>(&pointWCoords, &space),
CoordinatesFunctorQuad<WorldCoordVector, vtkm::CellShapeTagQuad>(
&pointWCoords, &space, &worklet),
space.ConvertCoordToSpace(wcoords),
Vector2(0.5f, 0.5f));
success = result.Valid;
return Vector3(result.Solution[0], result.Solution[1], 0);
}
} // namespace detail
static inline VTKM_EXEC vtkm::Vec<vtkm::FloatDefault, 3> WorldCoordinatesToParametricCoordinates(
const vtkm::VecAxisAlignedPointCoordinates<2>& pointWCoords,
const vtkm::Vec<vtkm::FloatDefault, 3>& wcoords,
vtkm::CellShapeTagQuad,
bool& success,
const FunctorBase&)
{
success = true;
return (wcoords - pointWCoords.GetOrigin()) / pointWCoords.GetSpacing();
}
template <typename WorldCoordVector>
static inline VTKM_EXEC typename WorldCoordVector::ComponentType
WorldCoordinatesToParametricCoordinates(const WorldCoordVector& pointWCoords,
const typename WorldCoordVector::ComponentType& wcoords,
vtkm::CellShapeTagQuad,
bool& success,
const vtkm::exec::FunctorBase& worklet)
{
vtkm::exec::internal::FastVec<WorldCoordVector, 4> local(pointWCoords);
return detail::WorldCoordinatesToParametricCoordinatesQuad(
local.Get(), wcoords, success, worklet);
}
//-----------------------------------------------------------------------------
template <typename WorldCoordVector>
static inline VTKM_EXEC typename WorldCoordVector::ComponentType
WorldCoordinatesToParametricCoordinates(const WorldCoordVector& pointWCoords,
const typename WorldCoordVector::ComponentType& wcoords,
vtkm::CellShapeTagPolygon,
bool& success,
const vtkm::exec::FunctorBase& worklet)
{
const vtkm::IdComponent numPoints = pointWCoords.GetNumberOfComponents();
VTKM_ASSERT(numPoints > 0);
switch (numPoints)
{
case 1:
return WorldCoordinatesToParametricCoordinates(
pointWCoords, wcoords, vtkm::CellShapeTagVertex(), success, worklet);
case 2:
return WorldCoordinatesToParametricCoordinates(
pointWCoords, wcoords, vtkm::CellShapeTagLine(), success, worklet);
case 3:
return WorldCoordinatesToParametricCoordinates(
pointWCoords, wcoords, vtkm::CellShapeTagTriangle(), success, worklet);
case 4:
return WorldCoordinatesToParametricCoordinates(
pointWCoords, wcoords, vtkm::CellShapeTagQuad(), success, worklet);
}
// If we are here, then there are 5 or more points on this polygon.
// Arrange the points such that they are on the circle circumscribed in the
// unit square from 0 to 1. That is, the point are on the circle centered at
// coordinate 0.5,0.5 with radius 0.5. The polygon is divided into regions
// defined by they triangle fan formed by the points around the center. This
// is C0 continuous but not necessarily C1 continuous. It is also possible to
// have a non 1 to 1 mapping between parametric coordinates world coordinates
// if the polygon is not planar or convex.
using WCoordType = typename WorldCoordVector::ComponentType;
// Find the position of the center point.
WCoordType wcoordCenter = pointWCoords[0];
for (vtkm::IdComponent pointIndex = 1; pointIndex < numPoints; pointIndex++)
{
wcoordCenter = wcoordCenter + pointWCoords[pointIndex];
}
wcoordCenter = wcoordCenter * WCoordType(1.0f / static_cast<float>(numPoints));
// Find the normal vector to the polygon. If the polygon is planar, convex,
// and in general position, any three points will give a normal in the same
// direction. Although not perfectly robust, we can reduce the effect of
// non-planar, non-convex, or degenerate polygons by picking three points
// topologically far from each other. Note that we do not care about the
// length of the normal in this case.
WCoordType polygonNormal;
{
WCoordType vec1 = pointWCoords[numPoints / 3] - pointWCoords[0];
WCoordType vec2 = pointWCoords[2 * numPoints / 3] - pointWCoords[1];
polygonNormal = vtkm::Cross(vec1, vec2);
}
// Find which triangle wcoords is located in. We do this by defining the
// equations for the planes through the radial edges and perpendicular to the
// polygon. The point is in the triangle if it is on the correct side of both
// planes.
vtkm::IdComponent firstPointIndex;
vtkm::IdComponent secondPointIndex = 0;
bool foundTriangle = false;
for (firstPointIndex = 0; firstPointIndex < numPoints - 1; firstPointIndex++)
{
WCoordType vecInPlane = pointWCoords[firstPointIndex] - wcoordCenter;
WCoordType planeNormal = vtkm::Cross(polygonNormal, vecInPlane);
typename WCoordType::ComponentType planeOffset = vtkm::Dot(planeNormal, wcoordCenter);
if (vtkm::Dot(planeNormal, wcoords) < planeOffset)
{
// wcoords on wrong side of plane, thus outside of triangle
continue;
}
secondPointIndex = firstPointIndex + 1;
vecInPlane = pointWCoords[secondPointIndex] - wcoordCenter;
planeNormal = vtkm::Cross(polygonNormal, vecInPlane);
planeOffset = vtkm::Dot(planeNormal, wcoordCenter);
if (vtkm::Dot(planeNormal, wcoords) > planeOffset)
{
// wcoords on wrong side of plane, thus outside of triangle
continue;
}
foundTriangle = true;
break;
}
if (!foundTriangle)
{
// wcoord was outside of all triangles we checked. It must be inside the
// one triangle we did not check (the one between the first and last
// polygon points).
firstPointIndex = numPoints - 1;
secondPointIndex = 0;
}
// Build a structure containing the points of the triangle wcoords is in and
// use the triangle version of this function to find the parametric
// coordinates.
vtkm::Vec<WCoordType, 3> triangleWCoords;
triangleWCoords[0] = wcoordCenter;
triangleWCoords[1] = pointWCoords[firstPointIndex];
triangleWCoords[2] = pointWCoords[secondPointIndex];
WCoordType trianglePCoords = WorldCoordinatesToParametricCoordinates(
triangleWCoords, wcoords, vtkm::CellShapeTagTriangle(), success, worklet);
// trianglePCoords is in the triangle's parameter space rather than the
// polygon's parameter space. We can find the polygon's parameter space by
// repurposing the ParametricCoordinatesToWorldCoordinates by using the
// polygon parametric coordinates as a proxy for world coordinates.
triangleWCoords[0] = WCoordType(0.5f, 0.5f, 0);
ParametricCoordinatesPoint(
numPoints, firstPointIndex, triangleWCoords[1], vtkm::CellShapeTagPolygon(), worklet);
ParametricCoordinatesPoint(
numPoints, secondPointIndex, triangleWCoords[2], vtkm::CellShapeTagPolygon(), worklet);
return ParametricCoordinatesToWorldCoordinates(
triangleWCoords, trianglePCoords, vtkm::CellShapeTagTriangle(), worklet);
}
//-----------------------------------------------------------------------------
namespace detail
{
template <typename WorldCoordVector>
static inline VTKM_EXEC typename WorldCoordVector::ComponentType
WorldCoordinatesToParametricCoordinatesTetra(
const WorldCoordVector& pointWCoords,
const typename WorldCoordVector::ComponentType& wcoords)
{
// We solve the world to parametric coordinates problem for tetrahedra
// similarly to that for triangles. Before understanding this code, you
// should understand the triangle code (in ReverseInterpolateTriangle in
// CellInterpolate.h). Go ahead. Read it now.
//
// The tetrahedron code is an obvious extension of the triangle code by
// considering the parallelpiped formed by wcoords and p0 of the triangle
// and the three adjacent faces. This parallelpiped is equivalent to the
// axis-aligned cuboid anchored at the origin of parametric space.
//
// Just like the triangle, we compute the parametric coordinate for each axis
// by intersecting a plane with each edge emanating from p0. The plane is
// defined by the one that goes through wcoords (duh) and is parallel to the
// plane formed by the other two edges emanating from p0 (as dictated by the
// aforementioned parallelpiped).
//
// In review, by parameterizing the line by fraction of distance the distance
// from p0 to the adjacent point (which is itself the parametric coordinate
// we are after), we get the following definition for the intersection.
//
// d = Dot((wcoords - p0), planeNormal)/Dot((p1-p0), planeNormal)
//
const auto vec0 = pointWCoords[1] - pointWCoords[0];
const auto vec1 = pointWCoords[2] - pointWCoords[0];
const auto vec2 = pointWCoords[3] - pointWCoords[0];
const auto coordVec = wcoords - pointWCoords[0];
typename WorldCoordVector::ComponentType pcoords;
auto planeNormal = vtkm::Cross(vec1, vec2);
pcoords[0] = vtkm::Dot(coordVec, planeNormal) / vtkm::Dot(vec0, planeNormal);
planeNormal = vtkm::Cross(vec0, vec2);
pcoords[1] = vtkm::Dot(coordVec, planeNormal) / vtkm::Dot(vec1, planeNormal);
planeNormal = vtkm::Cross(vec0, vec1);
pcoords[2] = vtkm::Dot(coordVec, planeNormal) / vtkm::Dot(vec2, planeNormal);
return pcoords;
}
} // detail
template <typename WorldCoordVector>
static inline VTKM_EXEC typename WorldCoordVector::ComponentType
WorldCoordinatesToParametricCoordinates(const WorldCoordVector& pointWCoords,
const typename WorldCoordVector::ComponentType& wcoords,
vtkm::CellShapeTagTetra,
bool& success,
const vtkm::exec::FunctorBase&)
{
success = true;
vtkm::exec::internal::FastVec<WorldCoordVector, 4> local(pointWCoords);
return detail::WorldCoordinatesToParametricCoordinatesTetra(local.Get(), wcoords);
}
//-----------------------------------------------------------------------------
namespace detail
{
template <typename WorldCoordVector, typename CellShapeTag>
class JacobianFunctor3DCell
{
using T = typename WorldCoordVector::ComponentType::ComponentType;
using Vector3 = vtkm::Vec<T, 3>;
using Matrix3x3 = vtkm::Matrix<T, 3, 3>;
const WorldCoordVector* PointWCoords;
public:
VTKM_EXEC
JacobianFunctor3DCell(const WorldCoordVector* pointWCoords)
: PointWCoords(pointWCoords)
{
}
VTKM_EXEC
Matrix3x3 operator()(const Vector3& pcoords) const
{
Matrix3x3 jacobian;
vtkm::exec::JacobianFor3DCell(*this->PointWCoords, pcoords, jacobian, CellShapeTag());
return jacobian;
}
};
template <typename WorldCoordVector, typename CellShapeTag>
class CoordinatesFunctor3DCell
{
using T = typename WorldCoordVector::ComponentType::ComponentType;
using Vector3 = vtkm::Vec<T, 3>;
const WorldCoordVector* PointWCoords;
const vtkm::exec::FunctorBase* Worklet;
public:
VTKM_EXEC
CoordinatesFunctor3DCell(const WorldCoordVector* pointWCoords,
const vtkm::exec::FunctorBase* worklet)
: PointWCoords(pointWCoords)
, Worklet(worklet)
{
}
VTKM_EXEC
Vector3 operator()(Vector3 pcoords) const
{
return vtkm::exec::ParametricCoordinatesToWorldCoordinates(
*this->PointWCoords, pcoords, CellShapeTag(), *this->Worklet);
}
};
template <typename WorldCoordVector, typename CellShapeTag>
static inline VTKM_EXEC typename WorldCoordVector::ComponentType
WorldCoordinatesToParametricCoordinates3D(const WorldCoordVector& pointWCoords,
const typename WorldCoordVector::ComponentType& wcoords,
CellShapeTag,
bool& success,
const vtkm::exec::FunctorBase& worklet)
{
auto result = vtkm::NewtonsMethod(
JacobianFunctor3DCell<WorldCoordVector, CellShapeTag>(&pointWCoords),
CoordinatesFunctor3DCell<WorldCoordVector, CellShapeTag>(&pointWCoords, &worklet),
wcoords,
typename WorldCoordVector::ComponentType(0.5f, 0.5f, 0.5f));
success = result.Valid;
return result.Solution;
}
} // detail
static inline VTKM_EXEC vtkm::Vec<vtkm::FloatDefault, 3> WorldCoordinatesToParametricCoordinates(
const vtkm::VecAxisAlignedPointCoordinates<3>& pointWCoords,
const vtkm::Vec<vtkm::FloatDefault, 3>& wcoords,
vtkm::CellShapeTagHexahedron,
bool& success,
const FunctorBase&)
{
success = true;
return (wcoords - pointWCoords.GetOrigin()) / pointWCoords.GetSpacing();
}
template <typename WorldCoordVector>
static inline VTKM_EXEC typename WorldCoordVector::ComponentType
WorldCoordinatesToParametricCoordinates(const WorldCoordVector& pointWCoords,
const typename WorldCoordVector::ComponentType& wcoords,
vtkm::CellShapeTagHexahedron,
bool& success,
const vtkm::exec::FunctorBase& worklet)
{
vtkm::exec::internal::FastVec<WorldCoordVector, 8> local(pointWCoords);
return detail::WorldCoordinatesToParametricCoordinates3D(
local.Get(), wcoords, vtkm::CellShapeTagHexahedron(), success, worklet);
}
template <typename WorldCoordVector>
static inline VTKM_EXEC typename WorldCoordVector::ComponentType
WorldCoordinatesToParametricCoordinates(const WorldCoordVector& pointWCoords,
const typename WorldCoordVector::ComponentType& wcoords,
vtkm::CellShapeTagWedge,
bool& success,
const vtkm::exec::FunctorBase& worklet)
{
vtkm::exec::internal::FastVec<WorldCoordVector, 6> local(pointWCoords);
return detail::WorldCoordinatesToParametricCoordinates3D(
local.Get(), wcoords, vtkm::CellShapeTagWedge(), success, worklet);
}
template <typename WorldCoordVector>
static inline VTKM_EXEC typename WorldCoordVector::ComponentType
WorldCoordinatesToParametricCoordinates(const WorldCoordVector& pointWCoords,
const typename WorldCoordVector::ComponentType& wcoords,
vtkm::CellShapeTagPyramid,
bool& success,
const vtkm::exec::FunctorBase& worklet)
{
vtkm::exec::internal::FastVec<WorldCoordVector, 5> local(pointWCoords);
return detail::WorldCoordinatesToParametricCoordinates3D(
local.Get(), wcoords, vtkm::CellShapeTagPyramid(), success, worklet);
}
//-----------------------------------------------------------------------------
template <typename WorldCoordVector>
static inline VTKM_EXEC typename WorldCoordVector::ComponentType
WorldCoordinatesToParametricCoordinates(const WorldCoordVector& pointWCoords,
const typename WorldCoordVector::ComponentType& wcoords,
vtkm::CellShapeTagGeneric shape,
bool& success,
const vtkm::exec::FunctorBase& worklet)
{
typename WorldCoordVector::ComponentType result;
switch (shape.Id)
{
vtkmGenericCellShapeMacro(result = WorldCoordinatesToParametricCoordinates(
pointWCoords, wcoords, CellShapeTag(), success, worklet));
default:
success = false;
worklet.RaiseError("Unknown cell shape sent to world 2 parametric.");
return typename WorldCoordVector::ComponentType();
}
return result;
}
}
} // namespace vtkm::exec
#endif //vtk_m_exec_ParametricCoordinates_h