mirror of
https://gitlab.kitware.com/vtk/vtk-m
synced 2024-10-08 11:29:02 +00:00
905 lines
29 KiB
C++
905 lines
29 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.
|
|
//============================================================================
|
|
#ifndef vtk_m_ImplicitFunction_h
|
|
#define vtk_m_ImplicitFunction_h
|
|
|
|
#include <vtkm/Bounds.h>
|
|
#include <vtkm/Math.h>
|
|
#include <vtkm/VecVariable.h>
|
|
#include <vtkm/VectorAnalysis.h>
|
|
#include <vtkm/exec/Variant.h>
|
|
|
|
// For interface class only.
|
|
#include <vtkm/cont/ExecutionAndControlObjectBase.h>
|
|
|
|
namespace vtkm
|
|
{
|
|
|
|
//============================================================================
|
|
namespace internal
|
|
{
|
|
|
|
/// \brief Base class for all `ImplicitFunction` classes.
|
|
///
|
|
/// `ImplicitFunctionBase` uses the curiously recurring template pattern (CRTP). Subclasses
|
|
/// must provide their own type for the template parameter. Subclasses must implement
|
|
/// `Value` and `Gradient` methods.
|
|
///
|
|
/// Also, all subclasses must be trivially copiable. This is so they can be copied among
|
|
/// host and devices.
|
|
///
|
|
template <typename Derived>
|
|
class ImplicitFunctionBase : public vtkm::cont::ExecutionAndControlObjectBase
|
|
{
|
|
public:
|
|
using Scalar = vtkm::FloatDefault;
|
|
using Vector = vtkm::Vec<Scalar, 3>;
|
|
|
|
/// @brief Evaluate the value of the implicit function.
|
|
///
|
|
/// The `Value()` method for an implicit function takes a `vtkm::Vec3f` and
|
|
/// returns a `vtkm::FloatDefault` representing the orientation of the point
|
|
/// with respect to the implicit function's shape. Negative scalar values
|
|
/// represent vector points inside of the implicit function's shape. Positive
|
|
/// scalar values represent vector points outside the implicit function's shape.
|
|
/// Zero values represent vector points that lie on the surface of the implicit
|
|
/// function.
|
|
VTKM_EXEC_CONT Scalar Value(Scalar x, Scalar y, Scalar z) const
|
|
{
|
|
return reinterpret_cast<const Derived*>(this)->Value(Vector(x, y, z));
|
|
}
|
|
|
|
/// @brief Evaluate the gradient of the implicit function.
|
|
///
|
|
/// The ``Gradient()`` method for an implicit function takes a `vtkm::Vec3f`
|
|
/// and returns a `vtkm::Vec3f` representing the pointing direction from the
|
|
/// implicit function's shape. Gradient calculations are more object shape
|
|
/// specific. It is advised to look at the individual shape implementations
|
|
/// for specific implicit functions.
|
|
VTKM_EXEC_CONT Vector Gradient(Scalar x, Scalar y, Scalar z) const
|
|
{
|
|
return reinterpret_cast<const Derived*>(this)->Gradient(Vector(x, y, z));
|
|
}
|
|
|
|
VTKM_CONT Derived PrepareForExecution(vtkm::cont::DeviceAdapterId, vtkm::cont::Token&) const
|
|
{
|
|
return *reinterpret_cast<const Derived*>(this);
|
|
}
|
|
|
|
VTKM_CONT Derived PrepareForControl() const { return *reinterpret_cast<const Derived*>(this); }
|
|
};
|
|
|
|
} // namespace vtkm::internal
|
|
|
|
//============================================================================
|
|
/// A helpful functor that calls the value method of a given `ImplicitFunction`. Can be
|
|
/// passed to things that expect a functor instead of an `ImplictFunction` class (like an array
|
|
/// transform).
|
|
///
|
|
template <typename FunctionType>
|
|
class ImplicitFunctionValueFunctor
|
|
{
|
|
public:
|
|
using Scalar = typename FunctionType::Scalar;
|
|
using Vector = typename FunctionType::Vector;
|
|
|
|
ImplicitFunctionValueFunctor() = default;
|
|
|
|
VTKM_EXEC_CONT ImplicitFunctionValueFunctor(
|
|
const vtkm::internal::ImplicitFunctionBase<FunctionType>& function)
|
|
: Function(reinterpret_cast<const FunctionType&>(function))
|
|
{
|
|
}
|
|
|
|
VTKM_EXEC_CONT ImplicitFunctionValueFunctor(const FunctionType& function)
|
|
: Function(function)
|
|
{
|
|
}
|
|
|
|
VTKM_EXEC_CONT Scalar operator()(const Vector& point) const
|
|
{
|
|
return this->Function.Value(point);
|
|
}
|
|
|
|
private:
|
|
FunctionType Function;
|
|
};
|
|
|
|
/// A helpful functor that calls the gradient method of a given `ImplicitFunction`. Can be
|
|
/// passed to things that expect a functor instead of an `ImplictFunction` class (like an array
|
|
/// transform).
|
|
///
|
|
template <typename FunctionType>
|
|
class ImplicitFunctionGradientFunctor
|
|
{
|
|
public:
|
|
using Scalar = typename FunctionType::Scalar;
|
|
using Vector = typename FunctionType::Vector;
|
|
|
|
ImplicitFunctionGradientFunctor() = default;
|
|
|
|
VTKM_EXEC_CONT ImplicitFunctionGradientFunctor(
|
|
const vtkm::internal::ImplicitFunctionBase<FunctionType>& function)
|
|
: Function(reinterpret_cast<const FunctionType&>(function))
|
|
{
|
|
}
|
|
|
|
VTKM_EXEC_CONT ImplicitFunctionGradientFunctor(const FunctionType& function)
|
|
: Function(function)
|
|
{
|
|
}
|
|
|
|
VTKM_EXEC_CONT Vector operator()(const Vector& point) const
|
|
{
|
|
return this->Function->Gradient(point);
|
|
}
|
|
|
|
private:
|
|
FunctionType Function;
|
|
};
|
|
|
|
//============================================================================
|
|
/// @brief Implicit function for a box
|
|
///
|
|
/// `Box` computes the implicit function and/or gradient for a axis-aligned
|
|
/// bounding box. Each side of the box is orthogonal to all other sides
|
|
/// meeting along shared edges and all faces are orthogonal to the x-y-z
|
|
/// coordinate axes.
|
|
|
|
class VTKM_ALWAYS_EXPORT Box : public internal::ImplicitFunctionBase<Box>
|
|
{
|
|
public:
|
|
/// @brief Construct box with center at (0,0,0) and each side of length 1.0.
|
|
VTKM_EXEC_CONT Box()
|
|
: MinPoint(Vector(Scalar(-0.5)))
|
|
, MaxPoint(Vector(Scalar(0.5)))
|
|
{
|
|
}
|
|
|
|
/// @brief Construct a box with the specified minimum and maximum point.
|
|
VTKM_EXEC_CONT Box(const Vector& minPoint, const Vector& maxPoint)
|
|
: MinPoint(minPoint)
|
|
, MaxPoint(maxPoint)
|
|
{
|
|
}
|
|
|
|
/// @brief Construct a box with the specified minimum and maximum point.
|
|
VTKM_EXEC_CONT Box(Scalar xmin, Scalar xmax, Scalar ymin, Scalar ymax, Scalar zmin, Scalar zmax)
|
|
: MinPoint(xmin, ymin, zmin)
|
|
, MaxPoint(xmax, ymax, zmax)
|
|
{
|
|
}
|
|
|
|
/// @brief Construct a box that encompasses the given bounds.
|
|
VTKM_CONT Box(const vtkm::Bounds& bounds) { this->SetBounds(bounds); }
|
|
|
|
/// @brief Specify the minimum coordinate of the box.
|
|
VTKM_CONT void SetMinPoint(const Vector& point) { this->MinPoint = point; }
|
|
|
|
/// @brief Specify the maximum coordinate of the box.
|
|
VTKM_CONT void SetMaxPoint(const Vector& point) { this->MaxPoint = point; }
|
|
|
|
/// @copydoc SetMinPoint
|
|
VTKM_EXEC_CONT const Vector& GetMinPoint() const { return this->MinPoint; }
|
|
|
|
/// @copydoc SetMaxPoint
|
|
VTKM_EXEC_CONT const Vector& GetMaxPoint() const { return this->MaxPoint; }
|
|
|
|
/// @brief Specify the size and location of the box by the bounds it encompasses.
|
|
VTKM_CONT void SetBounds(const vtkm::Bounds& bounds)
|
|
{
|
|
this->SetMinPoint({ Scalar(bounds.X.Min), Scalar(bounds.Y.Min), Scalar(bounds.Z.Min) });
|
|
this->SetMaxPoint({ Scalar(bounds.X.Max), Scalar(bounds.Y.Max), Scalar(bounds.Z.Max) });
|
|
}
|
|
|
|
/// @copydoc SetBounds
|
|
VTKM_EXEC_CONT vtkm::Bounds GetBounds() const
|
|
{
|
|
return vtkm::Bounds(vtkm::Range(this->MinPoint[0], this->MaxPoint[0]),
|
|
vtkm::Range(this->MinPoint[1], this->MaxPoint[1]),
|
|
vtkm::Range(this->MinPoint[2], this->MaxPoint[2]));
|
|
}
|
|
|
|
/// @copydoc internal::ImplicitFunctionBase::Value
|
|
VTKM_EXEC_CONT Scalar Value(const Vector& point) const
|
|
{
|
|
Scalar minDistance = vtkm::NegativeInfinity32();
|
|
Scalar diff, t, dist;
|
|
Scalar distance = Scalar(0.0);
|
|
vtkm::IdComponent inside = 1;
|
|
|
|
for (vtkm::IdComponent d = 0; d < 3; d++)
|
|
{
|
|
diff = this->MaxPoint[d] - this->MinPoint[d];
|
|
if (diff != Scalar(0.0))
|
|
{
|
|
t = (point[d] - this->MinPoint[d]) / diff;
|
|
// Outside before the box
|
|
if (t < Scalar(0.0))
|
|
{
|
|
inside = 0;
|
|
dist = this->MinPoint[d] - point[d];
|
|
}
|
|
// Outside after the box
|
|
else if (t > Scalar(1.0))
|
|
{
|
|
inside = 0;
|
|
dist = point[d] - this->MaxPoint[d];
|
|
}
|
|
else
|
|
{
|
|
// Inside the box in lower half
|
|
if (t <= Scalar(0.5))
|
|
{
|
|
dist = MinPoint[d] - point[d];
|
|
}
|
|
// Inside the box in upper half
|
|
else
|
|
{
|
|
dist = point[d] - MaxPoint[d];
|
|
}
|
|
if (dist > minDistance)
|
|
{
|
|
minDistance = dist;
|
|
}
|
|
}
|
|
}
|
|
else
|
|
{
|
|
dist = vtkm::Abs(point[d] - MinPoint[d]);
|
|
if (dist > Scalar(0.0))
|
|
{
|
|
inside = 0;
|
|
}
|
|
}
|
|
if (dist > Scalar(0.0))
|
|
{
|
|
distance += dist * dist;
|
|
}
|
|
}
|
|
|
|
distance = vtkm::Sqrt(distance);
|
|
if (inside)
|
|
{
|
|
return minDistance;
|
|
}
|
|
else
|
|
{
|
|
return distance;
|
|
}
|
|
}
|
|
|
|
/// @copydoc internal::ImplicitFunctionBase::Gradient
|
|
VTKM_EXEC_CONT Vector Gradient(const Vector& point) const
|
|
{
|
|
vtkm::IdComponent minAxis = 0;
|
|
Scalar dist = 0.0;
|
|
Scalar minDist = vtkm::Infinity32();
|
|
vtkm::IdComponent3 location;
|
|
Vector normal(Scalar(0));
|
|
Vector inside(Scalar(0));
|
|
Vector outside(Scalar(0));
|
|
Vector center((this->MaxPoint + this->MinPoint) * Scalar(0.5));
|
|
|
|
// Compute the location of the point with respect to the box
|
|
// Point will lie in one of 27 separate regions around or within the box
|
|
// Gradient vector is computed differently in each of the regions.
|
|
for (vtkm::IdComponent d = 0; d < 3; d++)
|
|
{
|
|
if (point[d] < this->MinPoint[d])
|
|
{
|
|
// Outside the box low end
|
|
location[d] = 0;
|
|
outside[d] = -1.0;
|
|
}
|
|
else if (point[d] > this->MaxPoint[d])
|
|
{
|
|
// Outside the box high end
|
|
location[d] = 2;
|
|
outside[d] = 1.0;
|
|
}
|
|
else
|
|
{
|
|
location[d] = 1;
|
|
if (point[d] <= center[d])
|
|
{
|
|
// Inside the box low end
|
|
dist = point[d] - this->MinPoint[d];
|
|
inside[d] = -1.0;
|
|
}
|
|
else
|
|
{
|
|
// Inside the box high end
|
|
dist = this->MaxPoint[d] - point[d];
|
|
inside[d] = 1.0;
|
|
}
|
|
if (dist < minDist) // dist is negative
|
|
{
|
|
minDist = dist;
|
|
minAxis = d;
|
|
}
|
|
}
|
|
}
|
|
|
|
vtkm::Id indx = location[0] + 3 * location[1] + 9 * location[2];
|
|
switch (indx)
|
|
{
|
|
// verts - gradient points away from center point
|
|
case 0:
|
|
case 2:
|
|
case 6:
|
|
case 8:
|
|
case 18:
|
|
case 20:
|
|
case 24:
|
|
case 26:
|
|
for (vtkm::IdComponent d = 0; d < 3; d++)
|
|
{
|
|
normal[d] = point[d] - center[d];
|
|
}
|
|
vtkm::Normalize(normal);
|
|
break;
|
|
|
|
// edges - gradient points out from axis of cube
|
|
case 1:
|
|
case 3:
|
|
case 5:
|
|
case 7:
|
|
case 9:
|
|
case 11:
|
|
case 15:
|
|
case 17:
|
|
case 19:
|
|
case 21:
|
|
case 23:
|
|
case 25:
|
|
for (vtkm::IdComponent d = 0; d < 3; d++)
|
|
{
|
|
if (outside[d] != 0.0)
|
|
{
|
|
normal[d] = point[d] - center[d];
|
|
}
|
|
else
|
|
{
|
|
normal[d] = 0.0;
|
|
}
|
|
}
|
|
vtkm::Normalize(normal);
|
|
break;
|
|
|
|
// faces - gradient points perpendicular to face
|
|
case 4:
|
|
case 10:
|
|
case 12:
|
|
case 14:
|
|
case 16:
|
|
case 22:
|
|
for (vtkm::IdComponent d = 0; d < 3; d++)
|
|
{
|
|
normal[d] = outside[d];
|
|
}
|
|
break;
|
|
|
|
// interior - gradient is perpendicular to closest face
|
|
case 13:
|
|
normal[0] = normal[1] = normal[2] = 0.0;
|
|
normal[minAxis] = inside[minAxis];
|
|
break;
|
|
default:
|
|
VTKM_ASSERT(false);
|
|
break;
|
|
}
|
|
return normal;
|
|
}
|
|
|
|
private:
|
|
Vector MinPoint;
|
|
Vector MaxPoint;
|
|
};
|
|
|
|
//============================================================================
|
|
/// \brief Implicit function for a cylinder
|
|
///
|
|
/// \c Cylinder computes the implicit function and function gradient
|
|
/// for a cylinder using F(r)=r^2-Radius^2. By default the Cylinder is
|
|
/// centered at the origin and the axis of rotation is along the
|
|
/// y-axis. You can redefine the center and axis of rotation by setting
|
|
/// the Center and Axis data members.
|
|
///
|
|
/// Note that the cylinder is infinite in extent.
|
|
///
|
|
class VTKM_ALWAYS_EXPORT Cylinder : public vtkm::internal::ImplicitFunctionBase<Cylinder>
|
|
{
|
|
public:
|
|
/// Construct cylinder radius of 0.5; centered at origin with axis
|
|
/// along y coordinate axis.
|
|
VTKM_EXEC_CONT Cylinder()
|
|
: Center(Scalar(0))
|
|
, Axis(Scalar(0), Scalar(1), Scalar(0))
|
|
, Radius(Scalar(0.5))
|
|
{
|
|
}
|
|
|
|
/// Construct a cylinder with the given axis and radius.
|
|
/// The cylinder is centered at the origin.
|
|
VTKM_EXEC_CONT Cylinder(const Vector& axis, Scalar radius)
|
|
: Center(Scalar(0))
|
|
, Axis(axis)
|
|
, Radius(radius)
|
|
{
|
|
}
|
|
|
|
/// Construct a cylinder at the given center, axis, and radius.
|
|
VTKM_EXEC_CONT Cylinder(const Vector& center, const Vector& axis, Scalar radius)
|
|
: Center(center)
|
|
, Axis(vtkm::Normal(axis))
|
|
, Radius(radius)
|
|
{
|
|
}
|
|
|
|
/// @brief Specify the center of the cylinder.
|
|
///
|
|
/// The axis of the cylinder goes through the center.
|
|
VTKM_CONT void SetCenter(const Vector& center) { this->Center = center; }
|
|
|
|
/// @brief Specify the direction of the axis of the cylinder.
|
|
VTKM_CONT void SetAxis(const Vector& axis) { this->Axis = vtkm::Normal(axis); }
|
|
|
|
/// @brief Specify the radius of the cylinder.
|
|
VTKM_CONT void SetRadius(Scalar radius) { this->Radius = radius; }
|
|
|
|
/// @copydoc internal::ImplicitFunctionBase::Value
|
|
VTKM_EXEC_CONT Scalar Value(const Vector& point) const
|
|
{
|
|
Vector x2c = point - this->Center;
|
|
FloatDefault proj = vtkm::Dot(this->Axis, x2c);
|
|
return vtkm::Dot(x2c, x2c) - (proj * proj) - (this->Radius * this->Radius);
|
|
}
|
|
|
|
/// @copydoc internal::ImplicitFunctionBase::Gradient
|
|
VTKM_EXEC_CONT Vector Gradient(const Vector& point) const
|
|
{
|
|
Vector x2c = point - this->Center;
|
|
FloatDefault t = this->Axis[0] * x2c[0] + this->Axis[1] * x2c[1] + this->Axis[2] * x2c[2];
|
|
vtkm::Vec<FloatDefault, 3> closestPoint = this->Center + (this->Axis * t);
|
|
return (point - closestPoint) * FloatDefault(2);
|
|
}
|
|
|
|
private:
|
|
Vector Center;
|
|
Vector Axis;
|
|
Scalar Radius;
|
|
};
|
|
|
|
//============================================================================
|
|
/// @brief Implicit function for a frustum
|
|
class VTKM_ALWAYS_EXPORT Frustum : public vtkm::internal::ImplicitFunctionBase<Frustum>
|
|
{
|
|
public:
|
|
/// @brief Construct axis-aligned frustum with center at (0,0,0) and each side of length 1.0.
|
|
Frustum() = default;
|
|
|
|
/// @brief Construct a frustum defined with 6 planes of the given points and normals.
|
|
VTKM_EXEC_CONT Frustum(const Vector points[6], const Vector normals[6])
|
|
{
|
|
this->SetPlanes(points, normals);
|
|
}
|
|
|
|
/// @brief Construct a frustum defined by the 8 points of the bounding hexahedron.
|
|
///
|
|
/// The points should be specified in the order of hex-cell vertices
|
|
VTKM_EXEC_CONT explicit Frustum(const Vector points[8]) { this->CreateFromPoints(points); }
|
|
|
|
/// @brief Specifies the 6 planes of the frustum.
|
|
VTKM_EXEC void SetPlanes(const Vector points[6], const Vector normals[6])
|
|
{
|
|
for (vtkm::Id index : { 0, 1, 2, 3, 4, 5 })
|
|
{
|
|
this->Points[index] = points[index];
|
|
}
|
|
for (vtkm::Id index : { 0, 1, 2, 3, 4, 5 })
|
|
{
|
|
this->Normals[index] = normals[index];
|
|
}
|
|
}
|
|
|
|
/// @brief Set one of the 6 planes of the frustum.
|
|
VTKM_EXEC void SetPlane(int idx, const Vector& point, const Vector& normal)
|
|
{
|
|
VTKM_ASSERT((idx >= 0) && (idx < 6));
|
|
this->Points[idx] = point;
|
|
this->Normals[idx] = normal;
|
|
}
|
|
|
|
/// @copydoc SetPlanes
|
|
VTKM_EXEC_CONT void GetPlanes(Vector points[6], Vector normals[6]) const
|
|
{
|
|
for (vtkm::Id index : { 0, 1, 2, 3, 4, 5 })
|
|
{
|
|
points[index] = this->Points[index];
|
|
}
|
|
for (vtkm::Id index : { 0, 1, 2, 3, 4, 5 })
|
|
{
|
|
normals[index] = this->Normals[index];
|
|
}
|
|
}
|
|
|
|
VTKM_EXEC_CONT const Vector* GetPoints() const { return this->Points; }
|
|
|
|
VTKM_EXEC_CONT const Vector* GetNormals() const { return this->Normals; }
|
|
|
|
/// @brief Specifies the frustum as the 8 points of the bounding hexahedron.
|
|
///
|
|
/// The points should be specified in the order of hex-cell vertices
|
|
VTKM_EXEC_CONT void CreateFromPoints(const Vector points[8])
|
|
{
|
|
// XXX(clang-format-3.9): 3.8 is silly. 3.9 makes it look like this.
|
|
// clang-format off
|
|
int planes[6][3] = {
|
|
{ 3, 2, 0 }, { 4, 5, 7 }, { 0, 1, 4 }, { 1, 2, 5 }, { 2, 3, 6 }, { 3, 0, 7 }
|
|
};
|
|
// clang-format on
|
|
|
|
for (int i = 0; i < 6; ++i)
|
|
{
|
|
const Vector& v0 = points[planes[i][0]];
|
|
const Vector& v1 = points[planes[i][1]];
|
|
const Vector& v2 = points[planes[i][2]];
|
|
|
|
this->Points[i] = v0;
|
|
this->Normals[i] = vtkm::Normal(vtkm::TriangleNormal(v0, v1, v2));
|
|
}
|
|
}
|
|
|
|
/// @copydoc internal::ImplicitFunctionBase::Value
|
|
VTKM_EXEC_CONT Scalar Value(const Vector& point) const
|
|
{
|
|
Scalar maxVal = vtkm::NegativeInfinity<Scalar>();
|
|
for (vtkm::Id index : { 0, 1, 2, 3, 4, 5 })
|
|
{
|
|
const Vector& p = this->Points[index];
|
|
const Vector& n = this->Normals[index];
|
|
const Scalar val = vtkm::Dot(point - p, n);
|
|
maxVal = vtkm::Max(maxVal, val);
|
|
}
|
|
return maxVal;
|
|
}
|
|
|
|
/// @copydoc internal::ImplicitFunctionBase::Gradient
|
|
VTKM_EXEC_CONT Vector Gradient(const Vector& point) const
|
|
{
|
|
Scalar maxVal = vtkm::NegativeInfinity<Scalar>();
|
|
vtkm::Id maxValIdx = 0;
|
|
for (vtkm::Id index : { 0, 1, 2, 3, 4, 5 })
|
|
{
|
|
const Vector& p = this->Points[index];
|
|
const Vector& n = this->Normals[index];
|
|
Scalar val = vtkm::Dot(point - p, n);
|
|
if (val > maxVal)
|
|
{
|
|
maxVal = val;
|
|
maxValIdx = index;
|
|
}
|
|
}
|
|
return this->Normals[maxValIdx];
|
|
}
|
|
|
|
private:
|
|
Vector Points[6] = { { -0.5f, 0.0f, 0.0f }, { 0.5f, 0.0f, 0.0f }, { 0.0f, -0.5f, 0.0f },
|
|
{ 0.0f, 0.5f, 0.0f }, { 0.0f, 0.0f, -0.5f }, { 0.0f, 0.0f, 0.5f } };
|
|
Vector Normals[6] = { { -1.0f, 0.0f, 0.0f }, { 1.0f, 0.0f, 0.0f }, { 0.0f, -1.0f, 0.0f },
|
|
{ 0.0f, 1.0f, 0.0f }, { 0.0f, 0.0f, -1.0f }, { 0.0f, 0.0f, 1.0f } };
|
|
};
|
|
|
|
//============================================================================
|
|
/// \brief Implicit function for a plane
|
|
///
|
|
/// A plane is defined by a point in the plane and a normal to the plane.
|
|
/// The normal does not have to be a unit vector. The implicit function will
|
|
/// still evaluate to 0 at the plane, but the values outside the plane
|
|
/// (and the gradient) will be scaled by the length of the normal vector.
|
|
class VTKM_ALWAYS_EXPORT Plane : public vtkm::internal::ImplicitFunctionBase<Plane>
|
|
{
|
|
public:
|
|
/// Construct a plane through the origin with the given normal.
|
|
VTKM_EXEC_CONT explicit Plane(const Vector& normal = { 0, 0, 1 })
|
|
: Origin(Scalar(0))
|
|
, Normal(normal)
|
|
{
|
|
}
|
|
|
|
/// Construct a plane through the given point with the given normal.
|
|
VTKM_EXEC_CONT Plane(const Vector& origin, const Vector& normal)
|
|
: Origin(origin)
|
|
, Normal(normal)
|
|
{
|
|
}
|
|
|
|
/// @brief Specify the origin of the plane.
|
|
///
|
|
/// The origin can be any point on the plane.
|
|
VTKM_CONT void SetOrigin(const Vector& origin) { this->Origin = origin; }
|
|
|
|
/// @brief Specify the normal vector to the plane.
|
|
///
|
|
/// The magnitude of the plane does not matter (so long as it is more than zero) in terms
|
|
/// of the location of the plane where the implicit function equals 0. However, if offsets
|
|
/// away from the plane matter then the magnitude determines the scale of the value away
|
|
/// from the plane.
|
|
VTKM_CONT void SetNormal(const Vector& normal) { this->Normal = normal; }
|
|
|
|
/// @copydoc SetOrigin
|
|
VTKM_EXEC_CONT const Vector& GetOrigin() const { return this->Origin; }
|
|
/// @copydoc SetNormal
|
|
VTKM_EXEC_CONT const Vector& GetNormal() const { return this->Normal; }
|
|
|
|
/// @copydoc internal::ImplicitFunctionBase::Value
|
|
VTKM_EXEC_CONT Scalar Value(const Vector& point) const
|
|
{
|
|
return vtkm::Dot(point - this->Origin, this->Normal);
|
|
}
|
|
|
|
/// @copydoc internal::ImplicitFunctionBase::Gradient
|
|
VTKM_EXEC_CONT Vector Gradient(const Vector&) const { return this->Normal; }
|
|
|
|
private:
|
|
Vector Origin;
|
|
Vector Normal;
|
|
};
|
|
|
|
//============================================================================
|
|
/// \brief Implicit function for a sphere
|
|
///
|
|
/// A sphere is defined by its center and a radius.
|
|
///
|
|
/// The value of the sphere implicit function is the square of the distance
|
|
/// from the center biased by the radius (so the surface of the sphere is
|
|
/// at value 0).
|
|
class VTKM_ALWAYS_EXPORT Sphere : public vtkm::internal::ImplicitFunctionBase<Sphere>
|
|
{
|
|
public:
|
|
/// Construct a sphere with center at (0,0,0) and the given radius.
|
|
VTKM_EXEC_CONT explicit Sphere(Scalar radius = 0.5)
|
|
: Radius(radius)
|
|
, Center(Scalar(0))
|
|
{
|
|
}
|
|
|
|
/// Construct a sphere with the given center and radius.
|
|
VTKM_EXEC_CONT Sphere(Vector center, Scalar radius)
|
|
: Radius(radius)
|
|
, Center(center)
|
|
{
|
|
}
|
|
|
|
/// Specify the radius of the sphere.
|
|
VTKM_CONT void SetRadius(Scalar radius) { this->Radius = radius; }
|
|
|
|
/// Specify the center of the sphere.
|
|
VTKM_CONT void SetCenter(const Vector& center) { this->Center = center; }
|
|
|
|
/// @copydoc SetRadius
|
|
VTKM_EXEC_CONT Scalar GetRadius() const { return this->Radius; }
|
|
|
|
/// @copydoc SetCenter
|
|
VTKM_EXEC_CONT const Vector& GetCenter() const { return this->Center; }
|
|
|
|
/// @copydoc internal::ImplicitFunctionBase::Value
|
|
VTKM_EXEC_CONT Scalar Value(const Vector& point) const
|
|
{
|
|
return vtkm::MagnitudeSquared(point - this->Center) - (this->Radius * this->Radius);
|
|
}
|
|
|
|
/// @copydoc internal::ImplicitFunctionBase::Gradient
|
|
VTKM_EXEC_CONT Vector Gradient(const Vector& point) const
|
|
{
|
|
return Scalar(2) * (point - this->Center);
|
|
}
|
|
|
|
private:
|
|
Scalar Radius;
|
|
Vector Center;
|
|
};
|
|
|
|
//============================================================================
|
|
/// \brief Implicit function for a MultiPlane
|
|
///
|
|
/// A MultiPlane contains multiple planes. Each plane is defined by a point and a normal to the plane.
|
|
/// MaxNumPlanes specifies the maximum number of planes it can hold. We can assign another MultiPlane with
|
|
/// a smaller number of planes to the current MultiPlane.
|
|
template <vtkm::IdComponent MaxNumPlanes>
|
|
class VTKM_ALWAYS_EXPORT MultiPlane
|
|
: public vtkm::internal::ImplicitFunctionBase<MultiPlane<MaxNumPlanes>>
|
|
{
|
|
public:
|
|
using Scalar = vtkm::FloatDefault;
|
|
using Vector = vtkm::Vec<Scalar, 3>;
|
|
VTKM_CONT MultiPlane() = default;
|
|
template <vtkm::IdComponent SrcMaxPlanes>
|
|
VTKM_CONT MultiPlane(const MultiPlane<SrcMaxPlanes>& src)
|
|
: Planes(src.GetPlanes())
|
|
{
|
|
}
|
|
template <vtkm::IdComponent SrcMaxPlanes>
|
|
VTKM_CONT MultiPlane& operator=(const MultiPlane<SrcMaxPlanes>& src)
|
|
{
|
|
this->Planes = vtkm::VecVariable<vtkm::Plane, MaxNumPlanes>{ src.GetPlanes() };
|
|
}
|
|
VTKM_CONT void AddPlane(const Vector& origin, const Vector& normal)
|
|
{
|
|
VTKM_ASSERT(this->Planes.GetNumberOfComponents() < MaxNumPlanes);
|
|
this->Planes.Append(Plane(origin, normal));
|
|
}
|
|
VTKM_CONT vtkm::Plane GetPlane(int idx)
|
|
{
|
|
VTKM_ASSERT((idx >= 0) && (idx < MaxNumPlanes));
|
|
return this->Planes[idx];
|
|
}
|
|
VTKM_CONT vtkm::VecVariable<vtkm::Plane, MaxNumPlanes> GetPlanes() const { return this->Planes; }
|
|
|
|
/// @copydoc internal::ImplicitFunctionBase::Value
|
|
VTKM_EXEC_CONT Scalar Value(const Vector& point) const
|
|
{
|
|
Scalar maxVal = vtkm::NegativeInfinity<Scalar>();
|
|
vtkm::IdComponent NumPlanes = this->Planes.GetNumberOfComponents();
|
|
for (vtkm::IdComponent index = 0; index < NumPlanes; ++index)
|
|
{
|
|
const Vector& p = this->Planes[index].GetOrigin();
|
|
const Vector& n = this->Planes[index].GetNormal();
|
|
const Scalar val = vtkm::Dot(point - p, n);
|
|
maxVal = vtkm::Max(maxVal, val);
|
|
}
|
|
return maxVal;
|
|
}
|
|
|
|
/// @copydoc internal::ImplicitFunctionBase::Gradient
|
|
VTKM_EXEC_CONT Vector Gradient(const Vector& point) const
|
|
{
|
|
Scalar maxVal = vtkm::NegativeInfinity<Scalar>();
|
|
vtkm::IdComponent maxValIdx = 0;
|
|
vtkm::IdComponent NumPlanes = Planes.GetNumberOfComponents();
|
|
for (vtkm::IdComponent index = 0; index < NumPlanes; ++index)
|
|
{
|
|
const Vector& p = this->Planes[index].GetOrigin();
|
|
const Vector& n = this->Planes[index].GetNormal();
|
|
Scalar val = vtkm::Dot(point - p, n);
|
|
if (val > maxVal)
|
|
{
|
|
maxVal = val;
|
|
maxValIdx = index;
|
|
}
|
|
}
|
|
return this->Planes[maxValIdx].GetNormal();
|
|
}
|
|
|
|
private:
|
|
vtkm::VecVariable<vtkm::Plane, MaxNumPlanes> Planes;
|
|
};
|
|
|
|
namespace detail
|
|
{
|
|
|
|
struct ImplicitFunctionValueFunctor
|
|
{
|
|
template <typename ImplicitFunctionType>
|
|
VTKM_EXEC_CONT typename ImplicitFunctionType::Scalar operator()(
|
|
const ImplicitFunctionType& function,
|
|
const typename ImplicitFunctionType::Vector& point) const
|
|
{
|
|
return function.Value(point);
|
|
}
|
|
};
|
|
|
|
struct ImplicitFunctionGradientFunctor
|
|
{
|
|
template <typename ImplicitFunctionType>
|
|
VTKM_EXEC_CONT typename ImplicitFunctionType::Vector operator()(
|
|
const ImplicitFunctionType& function,
|
|
const typename ImplicitFunctionType::Vector& point) const
|
|
{
|
|
return function.Gradient(point);
|
|
}
|
|
};
|
|
|
|
} // namespace detail
|
|
|
|
//============================================================================
|
|
/// \brief Implicit function that can switch among different types.
|
|
///
|
|
/// An `ImplicitFunctionMultiplexer` is a templated `ImplicitFunction` that takes
|
|
/// as template arguments any number of other `ImplicitFunction`s that it can
|
|
/// behave as. This allows you to decide at runtime which of these implicit
|
|
/// functions to define and compute.
|
|
///
|
|
/// For example, let's say you want a filter that finds points either inside
|
|
/// a sphere or inside a box. Rather than create 2 different filters, one for
|
|
/// each type of implicit function, you can use `ImplicitFunctionMultiplexer<Sphere, Box>`
|
|
/// and then set either a `Sphere` or a `Box` at runtime.
|
|
///
|
|
/// To use `ImplicitFunctionMultiplexer`, simply create the actual implicit
|
|
/// function that you want to use, and then set the `ImplicitFunctionMultiplexer`
|
|
/// to that concrete implicit function object.
|
|
///
|
|
template <typename... ImplicitFunctionTypes>
|
|
class ImplicitFunctionMultiplexer
|
|
: public vtkm::internal::ImplicitFunctionBase<
|
|
ImplicitFunctionMultiplexer<ImplicitFunctionTypes...>>
|
|
{
|
|
vtkm::exec::Variant<ImplicitFunctionTypes...> Variant;
|
|
|
|
using Superclass =
|
|
vtkm::internal::ImplicitFunctionBase<ImplicitFunctionMultiplexer<ImplicitFunctionTypes...>>;
|
|
|
|
public:
|
|
using Scalar = typename Superclass::Scalar;
|
|
using Vector = typename Superclass::Vector;
|
|
|
|
ImplicitFunctionMultiplexer() = default;
|
|
|
|
template <typename FunctionType>
|
|
VTKM_EXEC_CONT ImplicitFunctionMultiplexer(
|
|
const vtkm::internal::ImplicitFunctionBase<FunctionType>& function)
|
|
: Variant(reinterpret_cast<const FunctionType&>(function))
|
|
{
|
|
}
|
|
|
|
/// @copydoc internal::ImplicitFunctionBase::Value
|
|
VTKM_EXEC_CONT Scalar Value(const Vector& point) const
|
|
{
|
|
return this->Variant.CastAndCall(detail::ImplicitFunctionValueFunctor{}, point);
|
|
}
|
|
|
|
/// @copydoc internal::ImplicitFunctionBase::Gradient
|
|
VTKM_EXEC_CONT Vector Gradient(const Vector& point) const
|
|
{
|
|
return this->Variant.CastAndCall(detail::ImplicitFunctionGradientFunctor{}, point);
|
|
}
|
|
};
|
|
|
|
//============================================================================
|
|
/// @brief Implicit function that can switch among known implicit function types.
|
|
///
|
|
/// `ImplicitFunctionGeneral` can behave as any of the predefined implicit functions
|
|
/// provided by VTK-m. This is helpful when the type of implicit function is not
|
|
/// known at compile time. For example, say you want a filter that can operate on
|
|
/// an implicit function. Rather than compile separate versions of the filter, one
|
|
/// for each type of implicit function, you can compile the filter once for
|
|
/// `ImplicitFunctionGeneral` and then set the desired implicit function at runtime.
|
|
///
|
|
/// To use `ImplicitFunctionGeneral`, simply create the actual implicit
|
|
/// function that you want to use, and then set the `ImplicitFunctionGeneral`
|
|
/// to that concrete implicit function object.
|
|
///
|
|
/// `ImplicitFunctionGeneral` currently supports `vtkm::Box`, `vtkm::Cylinder`,
|
|
/// `vtkm::Frustum`, `vtkm::Plane`, and `vtkm::Sphere`.
|
|
///
|
|
class ImplicitFunctionGeneral
|
|
: public vtkm::ImplicitFunctionMultiplexer<vtkm::Box,
|
|
vtkm::Cylinder,
|
|
vtkm::Frustum,
|
|
vtkm::Plane,
|
|
vtkm::Sphere,
|
|
vtkm::MultiPlane<3>>
|
|
{
|
|
using Superclass = vtkm::ImplicitFunctionMultiplexer<vtkm::Box,
|
|
vtkm::Cylinder,
|
|
vtkm::Frustum,
|
|
vtkm::Plane,
|
|
vtkm::Sphere,
|
|
vtkm::MultiPlane<3>>;
|
|
|
|
public:
|
|
using Superclass::Superclass;
|
|
};
|
|
|
|
} // namespace vtkm
|
|
|
|
#endif //vtk_m_ImplicitFunction_h
|