# This example shows how to color an isosurface with other data. Basically
# an isosurface is generated, and a data array is selected and used by the
# mapper to color the surface.

package require vtk
package require vtkinteraction

# Read some data. The important thing here is to read a function as a data
# array as well as the scalar and vector.  (here function 153 is named
# "Velocity Magnitude").Later this data array will be used to color the
# isosurface.  
#
vtkPLOT3DReader pl3d
    pl3d SetXYZFileName "$VTK_DATA_ROOT/Data/combxyz.bin"
    pl3d SetQFileName "$VTK_DATA_ROOT/Data/combq.bin"
    pl3d SetScalarFunctionNumber 100
    pl3d SetVectorFunctionNumber 202
    pl3d AddFunction 153
    pl3d Update
    pl3d DebugOn
    
# The contoru filter uses the labeled scalar (function number 100
# above to generate the contour surface; all other data is interpolated
# during the contouring process.
#
vtkContourFilter iso
    iso SetInputConnection [pl3d GetOutputPort]
    iso SetValue 0 .24

vtkPolyDataNormals normals
    normals SetInputConnection [iso GetOutputPort]
    normals SetFeatureAngle 45

# We indicate to the mapper to use the velcoity magnitude, which is a 
# vtkDataArray that makes up part of the point attribute data.
#
vtkPolyDataMapper isoMapper
    isoMapper SetInputConnection [normals GetOutputPort]
    isoMapper ScalarVisibilityOn
    isoMapper SetScalarRange 0 1500
    isoMapper SetScalarModeToUsePointFieldData
    isoMapper ColorByArrayComponent "VelocityMagnitude" 0

vtkLODActor isoActor
    isoActor SetMapper isoMapper
    isoActor SetNumberOfCloudPoints 1000

vtkStructuredGridOutlineFilter outline
    outline SetInputConnection [pl3d GetOutputPort]
vtkPolyDataMapper outlineMapper
    outlineMapper SetInputConnection [outline GetOutputPort]
vtkActor outlineActor
    outlineActor SetMapper outlineMapper

# Create the usual rendering stuff.
#
vtkRenderer ren1
vtkRenderWindow renWin
    renWin AddRenderer ren1
vtkRenderWindowInteractor iren
    iren SetRenderWindow renWin

# Add the actors to the renderer, set the background and size
#
ren1 AddActor outlineActor
ren1 AddActor isoActor
ren1 SetBackground 1 1 1
renWin SetSize 500 500
ren1 SetBackground 0.1 0.2 0.4

set cam1 [ren1 GetActiveCamera]
$cam1 SetClippingRange 3.95297 50
$cam1 SetFocalPoint 9.71821 0.458166 29.3999
$cam1 SetPosition 2.7439 -37.3196 38.7167
$cam1 SetViewUp -0.16123 0.264271 0.950876

# render the image
#
iren AddObserver UserEvent {wm deiconify .vtkInteract}
renWin Render

# prevent the tk window from showing up then start the event loop
wm withdraw .


