<p>我终于想办法做点什么了。
如果我很清楚,字形需要一个曲面,尤其是构成该曲面的每个点上的法线。每个法线给出每个字形的方向。
vtk源代码中<code>Examples/VisualizationAlgorithms/Python/spikeF.py</code>处的示例说明了我的意思。
下面是一个单独着色和旋转字形的小例子。在</p>
<pre><code>#!/usr/bin/env python
# -*- coding: utf-8 -*-
from vtk import *
# Let's create a surface with 3 points unconnected.
points = vtkPoints()
points.InsertNextPoint(1, 0, 0)
points.InsertNextPoint(0, 0, 0)
points.InsertNextPoint(0, 1, 0)
polydata = vtkPolyData()
polydata.SetPoints(points)
colors = vtkUnsignedCharArray()
colors.SetNumberOfComponents(3)
colors.SetNumberOfTuples(polydata.GetNumberOfPoints())
colors.InsertTuple3(0, 147, 25, 98)
colors.InsertTuple3(1, 32, 84, 247)
colors.InsertTuple3(2, 198, 214, 36)
polydata.GetPointData().SetScalars(colors)
# Now, let's control normal on each point composing or 'fake' surface
# We should say, let's give a direction to each point, a normal in strange for a point.
pointNormalsArray = vtkDoubleArray()
pointNormalsArray.SetNumberOfComponents(3)
pointNormalsArray.SetNumberOfTuples(polydata.GetNumberOfPoints())
pN1 = [1.0, 0.0, 0.0]
pN2 = [0.0, 1.0, 0.0]
pN3 = [0.0, 0.0, 1.0]
pointNormalsArray.SetTuple(0, pN1)
pointNormalsArray.SetTuple(1, pN2)
pointNormalsArray.SetTuple(2, pN3)
polydata.GetPointData().SetNormals(pointNormalsArray)
sources = vtkConeSource()
sources.SetResolution(6)
sources.Update()
glyph = vtkGlyph3D()
try:
glyph.SetInput(polydata)
except AttributeError:
glyph.SetInputData(polydata)
glyph.SetSourceConnection(sources.GetOutputPort())
glyph.SetColorModeToColorByScalar()
glyph.SetVectorModeToUseNormal()
glyph.ScalingOff()
glyph.Update()
mapper = vtkPolyDataMapper()
mapper.SetInputConnection(glyph.GetOutputPort())
actor = vtkActor()
actor.SetMapper(mapper)
ren = vtkRenderer()
ren.SetBackground(0.2, 0.5, 0.3)
ren.AddActor(actor)
renwin = vtk.vtkRenderWindow()
renwin.AddRenderer(ren)
iren = vtk.vtkRenderWindowInteractor()
iren.SetInteractorStyle(vtk.vtkInteractorStyleTrackballCamera())
iren.SetRenderWindow(renwin)
renwin.Render()
iren.Initialize()
renwin.Render()
iren.Start()
</code></pre>
<p>顺便说一句,还有一个更简单的解决方案,即创建一个源,以及所需的任何映射器和参与者。事实上,给每个演员一个颜色和方向是很容易的。问题是,对于很多演员(我的机器上大约有5000场)来说,表演对互动是很不利的。在</p>