Instructions for Deformed Bubbles

If the points constitute a topological sphere (i.e., is a single, deformed bubble), then you can probably just use vtkSurfaceReconstructionFilter(). However, if there are disjoint bubbles, then you first need to perform the powercrust algorithm to do the surface triangulation and then use a VTK script to visualize it.

For starters, be sure your data file contains only the 3D points (no line indicating how many points there are, etc.).

rf. modi4:/u/ncsa/heiland/Bubbles/Data
% alias python /u/ncsa/heiland/Python-1.6a2/python
% setenv LD_LIBRARY64_PATH /u/ncsa/heiland/VisBench/vtk64:$LD_LIBRARY64_PATH
 or just the following if LD_LIBRARY64_PATH isn't defined:
% setenv SGI_ABI -64
% setenv LD_LIBRARY64_PATH .:/u/ncsa/heiland/VisBench/vtk64
% setenv PYTHONPATH  .:/u/ncsa/heiland/VisBench/vtk64:/u/ncsa/heiland/Python-1.6a2/Lib

Single bubble:

% python movie.py -1 -1 surfpoints00.dat
  -- can do multiple files at once:
% python movie.py -1 -1 surfpoints00.dat   surfpoints01.dat   surfpoints02.dat

The first two parameters ("-1 -1", here) after the script name are the 'neighborhoodsize' and 'samplespacing' parameters to vtkSurfaceReconstructionFilter. Using "-1 -1" will cause it to default, and the default values will be printed out, e.g.:

----default:
nb= 20
ss= 2.09585142136

To make a finer mesh, you would decrease the 'samplespacing' parameter, e.g.:

% python movie.py -1 1.0 surfpoints00.dat

Multiple bubbles:

% powercrust -m 100000 -s 9427 -i surfpoints07.dat
  -- This creates 'pc.off'.
  -- Rename the powercrust output file if you want to save it.
  -- In fact, for doing a lot of files, you'd want to make a shell script.
% mv pc.off pc07.dat

--  Visualize results using a VTK script:
% python polyTri.py pc07.dat surfpoints07
  -- creates surfpoints07.ppm

Hopefully, the VTK-Python scripts are somewhat self-explanatory, allowing you to make changes as you desire. For example, to change the background color, you would modify the line "ren.SetBackground", using R,G,B as params; (1,1,1)=white, (0,0,0)=black. To change the color of the bubble or the X & Y labels, search for 'SetColor' in the script.

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