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Visualizing OpenFOAM VTK-files using mayavi/mlab in Python

Hi All,

I am trying to visualize my model results from OpenFOAM in python using mayavi/mlab. I am able to plot the surfaces of my model. However, I would like to make a quiverplot of my velocity field and a volume plot of my pressures. I found some documentation this. However, this documentation did not state anything on the combination with loaded VTK-files. The code beneath is the one I use for plotting the surfaces. Could anyone help me extend this to plotting the velocities and pressures using python?

Code:

import os

from mayavi.core.api import Engine

from mayavi.sources.vtk_file_reader import VTKFileReader

from mayavi.modules.surface import Surface

from mayavi import mlab

vtkFile_tot = os.path.normpath('D:/Bas/python/VTK/131023cutterBlended08RelVel_0.vtk')

engine = Engine()

engine.start()

scene = engine.new_scene()

reader = VTKFileReader()

reader.initialize(vtkFile_tot)

engine.add_source(reader)

surface = Surface()

engine.add_module(surface)

Working principle

After a while I found a way to visualise my VTK files generated by OpenFOAM using mayavi.

Code:

 import os



 # engine imports.

 from mayavi.scripts import mayavi2

 from mayavi.sources.api import VTKFileReader

 from mayavi.modules.glyph import Glyph

 from mayavi.filters.mask_points import MaskPoints

 from mayavi.core.api import Engine

 from mayavi import mlab

 



 # Create a new VTK scene if none is present yet

 def initializeVTK(filename):

     try:

         engine

     except NameError:

         global engine

         print 'warning is due to the check if the global variable named engine already exists'

         engine = Engine()

         engine.start()

     if len(engine.scenes) == 0:

        engine.new_scene()

     r = VTKFileReader()

     r.initialize(filename)

     engine.add_source(r)

 



 VTK=os.path.normpath('/myFolder/myVTK-file.vtk')

 initializeVTK(VTK)

 



 # Make a mask for the points

 m = MaskPoints()

 m.filter.set(on_ratio=300, random_mode=False)

 engine.add_filter(m) # this adds the module 'm' the engine

 g = Glyph()

 engine.add_module(g) # this adds the module 'g' the engine

 



 g.glyph.color_mode = 'color_by_vector'

 g.glyph.scale_mode = 'scale_by_vector'

 # Use arrows to view the scalars.

 gs = g.glyph.glyph_source

 gs.glyph_source = gs.glyph_dict['arrow_source']

 



 f = mlab.gcf()

 mlab.view(distance=3.5)

 f.scene.background = (1.0, 1.0, 1.0) # set background color   

 f.scene.render()

 mlab.show()