[vtkusers] Python and vtkPoints/vtkFloatArray problem

[Viksit Gaur]

Hi All,

I've just been experimenting with a program to render particles on
screen given coordinates for each as well as a scalar for each point -
as spheres. I found an article/tutorial on LinuxJournal which uses VTK
3, and I think I've ported it to VTK4 - since I don't get any errors.

But, all I see is the render window, without any display of points, or
any errors to point out what might be going wrong. The program is
given below - I'd appreciate  any help on this.

Thanks,
Viksit

=== Begin Program ==
import vtk
import time

sphere = vtk.vtkSphereSource()
glyphs = vtk.vtkGlyph3D()
glMapper = vtk.vtkPolyDataMapper()
glActor = vtk.vtkActor()

points = vtk.vtkPoints()
scalars = vtk.vtkFloatArray()

scalars.SetNumberOfComponents(1);
scalars.SetNumberOfTuples(10);

for i in range(0,10):
        points.InsertPoint(i,i+1,i+2, i+3)
        scalars.SetTuple1(i, 2.2)

pointset = vtk.vtkPolyData()
pointset.SetPoints(points)
pointset.GetPointData().SetScalars(scalars)

sphere.SetPhiResolution(2)
sphere.SetThetaResolution(2)
sphere.SetReleaseDataFlag(1)

#Set the attributes of the glyph objects
glyphs.ScalingOn()
glyphs.SetScaleModeToScaleByScalar()

#Set the mapper attributes
glMapper.ScalarVisibilityOff()

#Build the pipeline:
glyphs.SetSource(sphere.GetOutput())
glyphs.SetInput(pointset)

#The glyphs need position and geometry information (two inputs)
glMapper.SetInput(glyphs.GetOutput())
glActor.SetMapper(glMapper)


ren = vtk.vtkRenderer()
renWin = vtk.vtkRenderWindow()
iren = vtk.vtkRenderWindowInteractor()
renWin.AddRenderer(ren)
iren.SetRenderWindow(renWin)
ren.AddActor(glActor)
iren.Initialize()

== End Program ==

--
Viksit Gaur
Social Robotics Lab, Dept. of Computer Science,
Yale University
http://gundam.cs.yale.edu
http://viksit.com