title: Convert VTK to raster image (Ruby or Python)
body: <p>I have the results of a simulation on an unstructured 2D mesh. I usually export the results in VTK and visualize them with Paraview. This is what results look like.</p>
  
  <p><img src="https://i.stack.imgur.com/xBLhU.png" alt="Unstructured grid results"></p>
  
  <p>I would like to obtain a raster image from the results (with or without interpolation) to use it as a texture for visualization in a 3D software. From reading around I have gathered that I need to do some kind of resampling in order to convert from the unstructured grid to a 2d regular grid for the raster image.</p>
  
  <p>VTK can export to raster, but it exports only a full scene without any defined boundary so it requires manual tweaking to fit the image. </p>
  
  <p>Ideally I would like to export only the results within the results bounding box and 'map' them to a raster image programmatically with Ruby or Python.</p>