1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
|
// SPDX-FileCopyrightText: Copyright (c) Ken Martin, Will Schroeder, Bill Lorensen
// SPDX-License-Identifier: BSD-3-Clause
#include "vtkParametricHenneberg.h"
#include "vtkMath.h"
#include "vtkObjectFactory.h"
VTK_ABI_NAMESPACE_BEGIN
vtkStandardNewMacro(vtkParametricHenneberg);
//----------------------------------------------------------------------------//
vtkParametricHenneberg::vtkParametricHenneberg()
{
// Preset triangulation parameters
this->MinimumU = -1.0;
this->MaximumU = 1.0;
this->MinimumV = -vtkMath::Pi() / 2.;
this->MaximumV = vtkMath::Pi() / 2.;
this->JoinU = 0;
this->JoinV = 0;
this->TwistU = 0;
this->TwistV = 0;
this->ClockwiseOrdering = 0;
this->DerivativesAvailable = 1;
}
//----------------------------------------------------------------------------//
vtkParametricHenneberg::~vtkParametricHenneberg() = default;
//----------------------------------------------------------------------------//
void vtkParametricHenneberg::Evaluate(double uvw[3], double Pt[3], double Duvw[9])
{
// Copy the parameters out of the vector, for the sake of convenience.
double u = uvw[0];
double v = uvw[1];
// We're only going to need the u and v partial derivatives.
// The w partial derivatives are not needed.
double* Du = Duvw;
double* Dv = Duvw + 3;
// Location of the point. This parametrization was taken from:
// http://mathworld.wolfram.com/HennebergsMinimalSurface.html
Pt[0] = 2. * sinh(u) * cos(v) - 2. / 3. * sinh(3. * u) * cos(3. * v);
Pt[1] = 2. * sinh(u) * sin(v) + 2. / 3. * sinh(3. * u) * sin(3. * v);
Pt[2] = 2. * cosh(2. * u) * cos(2. * v);
// The derivative with respect to u:
Du[0] = 2. * cosh(u) * cos(v) - 2. * cosh(3. * u) * cos(3. * v);
Du[1] = 2. * cosh(u) * sin(v) + 2. * cosh(3. * u) * sin(3. * v);
Du[2] = 4. * sinh(2. * u) * cos(2. * v);
// The derivative with respect to v:
Dv[0] = -2. * sinh(u) * sin(v) + 2. * sinh(3. * u) * sin(3. * v);
Dv[1] = 2. * sinh(u) * cos(v) + 2. * sinh(3. * u) * cos(3. * v);
Dv[2] = -4. * cosh(2. * u) * sin(2. * v);
}
//----------------------------------------------------------------------------//
double vtkParametricHenneberg::EvaluateScalar(double*, double*, double*)
{
return 0;
}
//----------------------------------------------------------------------------//
void vtkParametricHenneberg::PrintSelf(ostream& os, vtkIndent indent)
{
this->Superclass::PrintSelf(os, indent);
}
VTK_ABI_NAMESPACE_END
|
