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
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
|
#!/usr/bin/env python
from vtkmodules.vtkCommonCore import vtkFloatArray
from vtkmodules.vtkCommonDataModel import (
vtkClosestNPointsStrategy,
vtkImageData,
)
from vtkmodules.vtkCommonMath import vtkRungeKutta4
from vtkmodules.vtkFiltersCore import vtkAppendFilter
from vtkmodules.vtkFiltersFlowPaths import (
vtkCompositeInterpolatedVelocityField,
vtkStreamTracer,
)
from vtkmodules.vtkFiltersModeling import vtkOutlineFilter
from vtkmodules.vtkFiltersSources import vtkLineSource
from vtkmodules.vtkRenderingCore import (
vtkActor,
vtkPolyDataMapper,
vtkRenderWindow,
vtkRenderWindowInteractor,
vtkRenderer,
)
import vtkmodules.vtkInteractionStyle
import vtkmodules.vtkRenderingFreeType
import vtkmodules.vtkRenderingOpenGL2
# Parameters for controlling the test size
dim = 40
numStreamlines = 50
# Create three volumes of different resolution and butt them together. This
# tests vtkPointSet::FindCell() on incompatible meshes (hanging and
# duplicate nodes).
spacing = 1.0 / (2.0*dim - 1.0)
v1 = vtkImageData()
v1.SetOrigin(0.0,0,0)
v1.SetDimensions(2*dim,2*dim,2*dim)
v1.SetSpacing(spacing,spacing,spacing)
spacing = 1.0 / (dim - 1.0)
v2 = vtkImageData()
v2.SetOrigin(1.0,0,0)
v2.SetDimensions(dim,dim,dim)
v2.SetSpacing(spacing,spacing,spacing)
spacing = 1.0 / (2.0*dim - 1.0)
v3 = vtkImageData()
v3.SetOrigin(2.0,0,0)
v3.SetDimensions(2*dim,2*dim,2*dim)
v3.SetSpacing(spacing,spacing,spacing)
# Append the volumes together to create an unstructured grid with duplicate
# and hanging points.
append = vtkAppendFilter()
append.AddInputData(v1)
append.AddInputData(v2)
append.AddInputData(v3)
append.MergePointsOff()
append.Update()
# Create a uniform vector field in the x-direction
numPts = append.GetOutput().GetNumberOfPoints()
vectors = vtkFloatArray()
vectors.SetNumberOfComponents(3)
vectors.SetNumberOfTuples(numPts);
for i in range(0,numPts):
vectors.SetTuple3(i, 1,0,0)
# A hack but it works
append.GetOutput().GetPointData().SetVectors(vectors)
# Outline around appended unstructured grid
outline = vtkOutlineFilter()
outline.SetInputConnection(append.GetOutputPort())
outlineMapper = vtkPolyDataMapper()
outlineMapper.SetInputConnection(outline.GetOutputPort())
outlineActor = vtkActor()
outlineActor.SetMapper(outlineMapper)
# Now create streamlines from a rake of seed points
pt1 = [0.001,0.1,0.5]
pt2 = [0.001,0.9,0.5]
line = vtkLineSource()
line.SetResolution(numStreamlines-1)
line.SetPoint1(pt1)
line.SetPoint2(pt2)
line.Update()
rk4 = vtkRungeKutta4()
strategy = vtkClosestNPointsStrategy()
ivp = vtkCompositeInterpolatedVelocityField()
ivp.SetFindCellStrategy(strategy)
streamer = vtkStreamTracer()
streamer.SetInputConnection(append.GetOutputPort())
streamer.SetSourceConnection(line.GetOutputPort())
streamer.SetMaximumPropagation(10)
streamer.SetInitialIntegrationStep(.2)
streamer.SetIntegrationDirectionToForward()
streamer.SetMinimumIntegrationStep(0.01)
streamer.SetMaximumIntegrationStep(0.5)
streamer.SetTerminalSpeed(1.0e-12)
streamer.SetMaximumError(1.0e-06)
streamer.SetComputeVorticity(0)
streamer.SetIntegrator(rk4)
streamer.SetInterpolatorPrototype(ivp)
streamer.Update()
reasons = streamer.GetOutput().GetCellData().GetArray("ReasonForTermination")
print(reasons.GetValue(0))
strMapper = vtkPolyDataMapper()
strMapper.SetInputConnection(streamer.GetOutputPort())
strActor = vtkActor()
strActor.SetMapper(strMapper)
# rendering
ren = vtkRenderer()
renWin = vtkRenderWindow()
iren = vtkRenderWindowInteractor()
renWin.AddRenderer(ren)
iren.SetRenderWindow(renWin)
ren.AddActor(outlineActor)
ren.AddActor(strActor)
ren.ResetCamera()
ren.GetActiveCamera().Zoom(2)
renWin.SetSize(600, 300)
renWin.Render()
iren.Start()
|
