polyHédronisme

This is a project built to demonstrate the Conway Polyhedral Operators and their extensions by George W. Hart. It was heavily inspired by some old code of George Hart's that did much the same in VRML. Additional operators are being added to increase the range of procedurally generated forms possible.

One derives any of a vast family of polyhedral shapes by specifying a core geometric 'seed' and then modifying it with topological and geometrical operators that derive more complex shapes from this base set.

It should runs on any modern canvas-enabled browser.

This project was also inspired by the renaissance tome Perspectiva Corporum Regularium featuring engravings by Jost Amman after designs and drawings by Wenzel Jamnitzer.

It is written in coffeescript. Uses jQuery, underscore, PEG.js parser for parsing recipes, and Eli Grey's BlobBuilder, FileSaver, canvas-toBlob for saving files.

Future

• Switch rendering to Three.JS
• WebGL frontend to replace the hand-rolled, slow canvas renderer, for those browsers that can use it.
• 2d vector export to SVG
• integration of csg.js lib for complex mesh joins
• geometric distortion operators, i.e.:

G x**2,y**2,z**2 => poly.xyz = _.map(poly.xyz, ([x,y,z]) -> [x*x,y*y,z*z])

• more geometric refinement operators:

FN - homogenize Face area - or at least, prevent faces from getting too small?

EN - homogenize Edge length

BN - attempt to Balance F and E, but always enforcing C

- more topological operators:

h - half (symbol clashes with the 'hollow' operator; could change the symbol for hollow to i as in skeletonize?) (caution: requires even-sided faces, and can produce digons)

c - chamfer

w - whirl

- Simple boolean operations on like-numbered faces: "cut and glue" - proper touch event handling for mobile - auto-rotation of the polyhedron (checkbox? play/pause button?) - compounding a series - does it work? - some documentation on what the palette colors map to. Currently, by "signature", which means what exactly? - add a UI control to change to this - the other choice is just by vertex count? - add a few examples to the index page (or a manual page). E.g.

• pC - propellerized cube
• tI - truncated icosahedron (soccer ball)
• eptI - exploded propellerized truncated icosahedron
• C300eC200pC200tI - ditto, canonicalized
• AeA3ptI - ditto, with convex spherical adjustment
• scccC - snub triple-chamfered cube
• k(4,1.8)k(3,1.8)C200eO
To do: give examples using kN or tN, and with a space-delimited series if that's supported.

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Text CC-BY, Code MIT License 2011 Anselm Levskaya