[vtkusers] 3D Plane with Color Mapping

[Eric Engelhard]

Please forgive my novice question and feel free to (gruffly) point me
towards an example. I have both vtk books and associated CDs. My first
effort is to create a 3D plane from a structured points data file and
map a color at each point. This plane will eventually be transformed
into a surface (holding z to zero just for now).

Questions:

1. Is the data set correctly formatted?
2. Am I misguided in my use of vtkStructuredPointsGeometryFilter below?
3. what is the best color mapping method to use here?

Much appreciated,

Eric Engelhard

My sample.vtk (no color mapping applied):

DATASET STRUCTURED_POINTS
DIMENSIONS 2810,2810,0
ORIGIN 0,0,0
SPACING 1,1,1

(lots of x,y,z data)

SCALARS co_mutation int 1

(scalar associated with each point listed above, range 1 - 125)

My sample.tcl:

catch {load vtktcl}
if { [catch {set VTK_TCL $env(VTK_TCL)}] != 0} { set VTK_TCL
"/usr/lib/vtk/examplesTcl" }
if { [catch {set VTK_DATA $env(VTK_DATA)}] != 0} { set VTK_DATA "~/vtk"
}
 
# get the interactor ui
source $VTK_TCL/vtkInt.tcl
 
# Create the RenderWindow, Renderer and both Actors
#
vtkRenderer ren1
vtkRenderWindow renWin
    renWin AddRenderer ren1
vtkRenderWindowInteractor iren
    iren SetRenderWindow renWin
 
#read from vtk file
vtkStructuredPointsReader data
    data SetFileName $VTK_DATA/structured_points_test.vtk
vtkStructuredPointsGeometryFilter polydata
    polydata SetInput [data GetOutput]
    polydata SetExtent 0 2810 0 2810 0 0
vtkPolyDataMapper planeMapper
    planeMapper SetInput [polydata GetOutput]
vtkActor planeActor
    planeActor SetMapper planeMapper
    [planeActor GetProperty] SetRepresentationToWireframe

# Add the actors to the renderer, set the background and size
#
ren1 AddActor planeMapper
ren1 SetBackground 0.1 0.2 0.4
renWin SetSize 500 500
 
# render the image
#
iren SetUserMethod {wm deiconify .vtkInteract}
set cam1 [ren1 GetActiveCamera]
$cam1 Zoom 1.4
iren Initialize
#renWin SetFileName "stl.tcl.ppm"
#renWin SaveImageAsPPM
 
# test regeneration of the LODMappers
stlActor Modified
 
# prevent the tk window from showing up then start the event loop
wm withdraw .

My error message:

Error in startup script: vtk bad argument, type conversion failed for
object planeMapper.
Could not type convert planeMapper which is of type
vtkOpenGLPolyDataMapper, to type vtkProp.
Object named: ren1, could not find requested method: AddActor
or the method was called with incorrect arguments.
 
    while executing
"ren1 AddActor planeMapper"
    (file "test_plane.tcl" line 30)