ParallelCoordinatesExtraction
Repository source: ParallelCoordinatesExtraction
Description¶
Using Parallel Coordinates View to plot and compare data set attributes, and then using selections in the parallel coordinates view to extract and view data points associated with those selections.
Question
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Code¶
ParallelCoordinatesExtraction.py
#!/usr/bin/env python
# Example of how to use Parallel Coordinates View to plot and compare
# data set attributes, and then to use selections in the parallel coordinates
# view to extract and view data points associated with those selections
# Use the 'u' character to toggle between 'inspect modes' on the parallel
# coordinates view (i.e. between selecting data and manipulating axes)
# Note that no points will show up inside of the 3d box outline until you
# select some lines/curves in the parallel coordinates view
# noinspection PyUnresolvedReferences
import vtkmodules.vtkInteractionStyle
# noinspection PyUnresolvedReferences
import vtkmodules.vtkRenderingOpenGL2
from vtkmodules.vtkCommonColor import vtkNamedColors
from vtkmodules.vtkCommonCore import vtkLookupTable
from vtkmodules.vtkFiltersCore import vtkElevationFilter
from vtkmodules.vtkFiltersExtraction import vtkExtractSelection
from vtkmodules.vtkFiltersGeneral import (
vtkAnnotationLink,
vtkBrownianPoints
)
from vtkmodules.vtkFiltersModeling import vtkOutlineFilter
from vtkmodules.vtkImagingCore import vtkRTAnalyticSource
from vtkmodules.vtkImagingGeneral import vtkImageGradient
from vtkmodules.vtkRenderingCore import (
vtkActor,
vtkDataSetMapper,
vtkPolyDataMapper,
vtkRenderWindow,
vtkRenderWindowInteractor,
vtkRenderer
)
from vtkmodules.vtkViewsInfovis import (
vtkParallelCoordinatesRepresentation,
vtkParallelCoordinatesView
)
def main():
colors = vtkNamedColors()
# Generate an image data set with multiple attribute arrays to probe and view
rt = vtkRTAnalyticSource()
rt.SetWholeExtent(-3, 3, -3, 3, -3, 3)
grad = vtkImageGradient()
grad.SetDimensionality(3)
grad.SetInputConnection(rt.GetOutputPort())
brown = vtkBrownianPoints()
brown.SetMinimumSpeed(0.5)
brown.SetMaximumSpeed(1.0)
brown.SetInputConnection(grad.GetOutputPort())
elev = vtkElevationFilter()
elev.SetLowPoint(-3, -3, -3)
elev.SetHighPoint(3, 3, 3)
elev.SetInputConnection(brown.GetOutputPort())
# Updating here because I will need to probe scalar ranges before
# the render window updates the pipeline
elev.Update()
# Set up parallel coordinates representation to be used in View
rep = vtkParallelCoordinatesRepresentation()
rep.SetInputConnection(elev.GetOutputPort())
rep.SetInputArrayToProcess(0, 0, 0, 0, 'RTDataGradient')
rep.SetInputArrayToProcess(1, 0, 0, 0, 'RTData')
rep.SetInputArrayToProcess(2, 0, 0, 0, 'Elevation')
rep.SetInputArrayToProcess(3, 0, 0, 0, 'BrownianVectors')
rep.SetUseCurves(0) # set to 1 to use smooth curves
rep.SetLineOpacity(0.5)
rep.SetAxisColor(colors.GetColor3d('Gold'))
rep.SetLineColor(colors.GetColor3d('MistyRose'))
# Set up the Parallel Coordinates View and hook in representation
view = vtkParallelCoordinatesView()
view.SetRepresentation(rep)
view.SetInspectMode(view.VTK_INSPECT_SELECT_DATA)
view.SetBrushOperatorToReplace()
view.SetBrushModeToLasso()
# Create a annotation link to access selection in parallel coordinates view
annotationLink = vtkAnnotationLink()
# If you don't set the FieldType explicitly it ends up as UNKNOWN
# (as of 21 Feb 2010)
# See vtkSelectionNode doc for field and content type enum values
annotationLink.GetCurrentSelection().GetNode(0).SetFieldType(1) # Point
annotationLink.GetCurrentSelection().GetNode(0).SetContentType(4) # Indices
# Update before passing annotationLink to vtkExtractSelection
annotationLink.Update()
# Connect the annotation link to the parallel coordinates representation
rep.SetAnnotationLink(annotationLink)
# Extract portion of data corresponding to parallel coordinates selection
extract = vtkExtractSelection()
extract.SetInputConnection(0, elev.GetOutputPort())
extract.SetInputConnection(1, annotationLink.GetOutputPort(2))
def update_render_windows(obj, event):
'''
Handle updating of RenderWindow since it's not a 'View'
and so not covered by vtkViewUpdater
:param obj:
:param event:
:return:
'''
# ren.ResetCamera()
renWin.Render()
# Set up callback to update 3d render window when selections are changed in
# parallel coordinates view
annotationLink.AddObserver('AnnotationChangedEvent', update_render_windows)
def toggle_inspectors(obj, event):
if view.GetInspectMode() == 0:
view.SetInspectMode(1)
else:
view.SetInspectMode(0)
# Set up callback to toggle between inspect modes (manip axes & select data)
view.GetInteractor().AddObserver('UserEvent', toggle_inspectors)
# 3D outline of image data bounds
outline = vtkOutlineFilter()
outline.SetInputConnection(elev.GetOutputPort())
outlineMapper = vtkPolyDataMapper()
outlineMapper.SetInputConnection(outline.GetOutputPort())
outlineActor = vtkActor()
outlineActor.SetMapper(outlineMapper)
# Build the lookup table for the 3d data scalar colors (brown to white)
lut = vtkLookupTable()
lut.SetTableRange(0, 256)
lut.SetHueRange(0.1, 0.1)
lut.SetSaturationRange(1.0, 0.1)
lut.SetValueRange(0.4, 1.0)
lut.Build()
# Set up the 3d rendering parameters
# of the image data which is selected in parallel coordinates
coloring_by = 'Elevation'
dataMapper = vtkDataSetMapper()
dataMapper.SetInputConnection(extract.GetOutputPort())
dataMapper.SetScalarModeToUsePointFieldData()
dataMapper.SetColorModeToMapScalars()
data = elev.GetOutputDataObject(0).GetPointData()
dataMapper.ScalarVisibilityOn()
dataMapper.SetScalarRange(data.GetArray(coloring_by).GetRange())
dataMapper.SetLookupTable(lut)
dataMapper.SelectColorArray(coloring_by)
dataActor = vtkActor()
dataActor.SetMapper(dataMapper)
dataActor.GetProperty().SetRepresentationToPoints()
dataActor.GetProperty().SetPointSize(10)
# Set up the 3d render window and add both actors
ren = vtkRenderer()
ren.AddActor(outlineActor)
ren.AddActor(dataActor)
renWin = vtkRenderWindow()
renWin.AddRenderer(ren)
renWin.SetWindowName('ParallelCoordinatesExtraction')
iren = vtkRenderWindowInteractor()
iren.SetRenderWindow(renWin)
ren.ResetCamera()
renWin.Render()
# Finalize parallel coordinates view and start interaction event loop
view.GetRenderWindow().SetSize(600, 300)
view.GetRenderWindow().SetWindowName('ParallelCoordinatesExtraction')
view.GetRenderer().GradientBackgroundOn()
view.GetRenderer().SetBackground2(colors.GetColor3d('DarkBlue'))
view.GetRenderer().SetBackground(colors.GetColor3d('MidnightBlue'))
view.ResetCamera()
view.Render()
view.GetInteractor().Start()
if __name__ == '__main__':
main()