VPython with Ruth Chabay and Bruce Sherwood - Episode 49

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Wouldn’t it be nice to be able to generate interactive 3D visualizations of physical systems in a declarative manner with Python? In this episode we spoke with Ruth Chabay and Bruce Sherwood about the VPython project which does just that. They tell us about how the use VPython in their classrooms, how the project got started, and the work they have done to bring it into the browser.

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  • Your hosts as usual are Tobias Macey and Chris Patti
  • Today we are interviewing Ruth Chabay and Bruce Sherwood about their work on VPython


  • Introductions
  • How did you get introduced to Python? – Chris
  • What is VPython and how did it get started? – Tobias
  • What problems inspired you to create VPython? – Chris
  • How do you design an API that allows for such powerful 3D visualization while still making it accessible to students who are focusing on learning new concepts in mathematics and physics so that they don’t get overwhelmed by the tool? – Tobias
  • I know many schools have embraced the open curriculum idea, have any of your physics courses using VPython been made available to the non matriculating public? – Chris
  • How does VPython perform its rendering? If you were to reimplement it would you do anything differently? – Tobias
  • One of the remarkable points about VPython is its ability to execute the simulations in a browser environment. Can you explain the technologies involved to make that work? – Tobias
  • Given the real-time rendering capabilities in VPython I’m sure that performance is a core concern for the project. What are some of the methods that are used to ensure an appropriate level of speed and does the cross-platform nature of the package pose any additional challenges? – Tobias
  • How does collision detection work in VPython, and does it handle more complex assemblies of component objects? – Chris
  • Can you talk a little bit about VPython’s design, and perhaps walk us through how a simple scene is rendered, say the results of the sphere() call? – Chris

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The intro and outro music is from Requiem for a Fish The Freak Fandango Orchestra / CC BY-SA

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