<![CDATA[how to create a multicolor polyhedron ?]]>Hello, to unfold my volumes I usually use a graphical editor (Wings 3d) and split it into pieces by painting each piece faces of the same color. I am wondering if there is a way to code that. Basically I have two splitting techniques, first one is to choose a number of pieces (N) then split the model into pieces having each (model faces count / N) faces. And second one is to make as many faces path as needed, it is hard to explain in few words. I am aware that is not something that JSCAD is made for but it is something that I'm willing to try for some time.
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]]>https://openjscad.nodebb.com/topic/353/how-to-create-a-multicolor-polyhedronRSS for NodeTue, 10 Mar 2026 15:42:50 GMTSat, 26 Mar 2022 11:02:24 GMT60<![CDATA[Reply to how to create a multicolor polyhedron ? on Sun, 27 Mar 2022 20:27:56 GMT]]>I changed my obj importer code to make it work with obj without groups. Now I can start to colorize my models by code. And there's one nice thing about that : I can use that faces coloring to store a volume's unfold pattern.
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]]>https://openjscad.nodebb.com/post/1152https://openjscad.nodebb.com/post/1152Sun, 27 Mar 2022 20:27:56 GMT<![CDATA[Reply to how to create a multicolor polyhedron ? on Sat, 26 Mar 2022 14:55:47 GMT]]>@z3dev I have an app that uses .obj so this format is my preffered one. For the moment when I export a polyhedron where I changed polygons.color values, I first need to import/export with Wings 3d for my app to be able to use it correctly, JSCAD doesn't create groups but add usemtl, I will look at my code to make it work without "g" lines.
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]]>https://openjscad.nodebb.com/post/1151https://openjscad.nodebb.com/post/1151Sat, 26 Mar 2022 14:55:47 GMT<![CDATA[Reply to how to create a multicolor polyhedron ? on Sat, 26 Mar 2022 14:06:14 GMT]]>As @hrgdavor mentioned, colors can be set per polygon. This will allow you to control the rendering. Are you exporting to a specific format?

]]>https://openjscad.nodebb.com/post/1150https://openjscad.nodebb.com/post/1150Sat, 26 Mar 2022 14:06:14 GMT<![CDATA[Reply to how to create a multicolor polyhedron ? on Sat, 26 Mar 2022 12:02:01 GMT]]>looking at jscad sourcecode you can set color on each polygon,
cd8a6544-f051-4e44-8f65-eec31b05461d-image.png

const jscad = require('@jscad/modeling')
const { cube } = jscad.primitives

function main(){
  const c = cube({size:10})
  c.polygons[0].color = [1,0,0]
  c.polygons[2].color = [0,1,0]
  console.log(c)
  return c
}

module.exports = {main}
]]>https://openjscad.nodebb.com/post/1149https://openjscad.nodebb.com/post/1149Sat, 26 Mar 2022 12:02:01 GMT