File:Heawood graph on torus.webm

Original file (WebM audio/video file, VP9, length 20 s, 1,024 × 768 pixels, 2.71 Mbps overall, file size: 6.47 MB)

Summary

Description
English: Heawood showed that maps drawn on an orientable surface of genus 1 require at most seven colors.To show that at least seven colors are required, he exhibited a map consisting of seven mutually adjacent hexagons. To visualize how this would look on a real torus we started with a planar representation of the toroidal embedding of the Heawood graph by David Eppstein. The planar representation was image mapped onto the torus using the open source ray tracer PovRay. It was then rendered several times at increasing angles to generate the video frames. The frames were stitched together using the open source program ffmpeg.
Date
Source Own work
Author PSL27

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Captions

Video of the Heawood graph mapped on the torus

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depicts

4 October 2020

video/webm

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Date/TimeThumbnailDimensionsUserComment
current00:20, 5 October 202020 s, 1,024 × 768 (6.47 MB)PSL27Uploaded own work with UploadWizard
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