Free Plugins for SketchUp

Sierpinski Tetrahedron

Download SketchUp Plugin

Background

Level 1 Sierpinski Tetrahedron Level 2 Sierpinski Tetrahedron Level 5 Sierpinski Tetrahedron

The Sierpinski Tetrahedron is a 3D fractal in the Mathematical world. It is defined recursively, where each level is constructed from components of the previous level. Like its cousin the Menger Sponge, by applying a few simple rules over and over one can create a complex and bizarre looking structure.

Actually, you don't need a plugin to do this. You can create any level of the Sierpinski Tetrahedron just using the SketchUp GUI. This plugin was basically an exercise in using the SketchUp Ruby API to build complex components from subcomponents. I left the source code unscrambled, if anyone wants view it.

In the first iteration, you start with a simple tetrahedron, scale it down to one half the size, make four copies, and arrange them in the tetrahedron-like shape pictured below. This is the first level tetrahedron.

The second iteration is the same procedure, only you apply it to the first level tetrahedron. The result is the second level tetrahedron.

For each iteration, apply the same process to four copies of the previous level tetrahedron. There is an image at the right showing how the fifth level tetrahedron looks. This plugin will construct the Sierpinski Tetrahedron up to the seventh level.

Usage

Sierpinski Tetrahedron Dialog Box

This plugin is accessed from the Draw menu (Draw > Sierpinski Tetrahedron). This will open a dialog box to enter the parameter values.

The outside color was left undefined, and shows up as white by default. You can easily change the outside color by clicking anywhere on the component with the paint bucket.

You can change the color of the inside faces almost as easily. Open the component by double-clicking on it with the select tool. The faces are grouped by material. So, if you click on any inside face with the paint bucket, all the faces that are the same color will be painted.

When you click OK, the Sierpinski Tetrahedron is created as a component, and the component placement tool is activated to position the spiral in the model.

The dialog box remembers the values between SketchUp sessions.

Installation and Removal

Installation Questions? Please see this SketchUp Help Article. To remove the plugin, just delete the file from the SketchUp Plugins folder.