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Mesh triangle reduction using quadrics - for Windows, OSX and Linux (thx Chris Rorden)


Summary Since I couldn't find any code that's fast, memory efficient, free and for high quality, I developed my version of the quadric based edge collapse mesh simplification method. It uses a threshold to determine which triangles to delete, which avoids sorting but might lead to lesser quality. It is about 4x as fast as Meshlab and can simplify 2M -> 30k triangles in 3.5 seconds.

Usage The functionality is contained in Simplify.h. The function to call is simplify_mesh(target_count). The code is kept pretty slim, so the main method has just around 400 lines of code.

Obj File Limitations The Obj file may only have one group or object. Its a very simple reader/writer, so don't try to use multiple objects in one file

Windows, OSX and Linux Command Line Tool added

Thanks to Chris Rorden for creating a command line version and providing binaries for OSX and Linux.

Pascal Version

Chris Rorden further created a pascal version that you can find here

License : MIT

Please don't forget to cite this page if you use the code!

Projects Using this Method


Surf Ice is a tool for surface rendering the cortex with overlays to illustrate tractography, network connections, anatomical atlases and statistical maps. While there are many alternatives, Surf Ice is easy to use and uses advances shaders to generate stunning images. It supports many popular mesh formats [3ds, ac3d, BrainVoyager (srf), ctm, Collada (dae), dfs, dxf, FreeSurfer (Asc, Srf, Curv, gcs, Pial, W), GIfTI (gii), gts, lwo, ms3d, mz3, nv, obj, off, ply, stl, vtk], connectome formats (edge/node) and tractography formats [bfloat, pdb, tck, trk, vtk].

img img

THREE.JS Sample using the Method


Live Web Version by Tiger Yuhao Huang


Unity Mesh Decimator by Mattias Edlund / Whinarn

.NET Mesh Decimator by Mattias Edlund / Whinarn

Javascript Mesh Decimator by Andrew Taber / ataber

Javascript Mesh Decimator by Joshua Koo / zz85

Java Mesh Decimator by Jayfella

Port from C++ to pure C by Chris Rorden. Includes routines for Marching Cubes and Laplacian HC mesh smoothing.


Mesh triangle reduction using quadrics







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