ZBrush Is Now A Grasshopper Plugin

-=NIK'S ZBRUSH COMMANDER=-

Work in progress, but I wrote a little Python script that can command the astoundingly powerful mesh modeler ZBrush to operate on meshes from within Grasshopper. It takes some work to create a ZScript macro for custom routines, but you can record those in ZBrush and then merely need to edit them into my script, inline, as bulk multiple-lines you just paste in, no problem as long as you strip the ZBrush button definition at the beginning.

ZBrush has a very high initial learning curve because of its non-standard interface. However, it has the world's most powerful quad remeshing and now mesh Booleans too. I needed a replacement for slow and especially non-robust marching cubes (Cocoon/Monolith/Dodo/Aether etc. on Grasshopper) that tended to bog down or blow up. IntraLattice was a step in a good direction but it can't merge fattened lines that merely cross each other with no breaks or that physically overlap on purpose to have many curve on in to a hub. But with $800 ZBrush 4R8, the latest version, that I can create English language ZScripts for, I suddenly have, often in the blink of an eye, or at worst a few seconds, right back into Rhino Grasshopper, a perfectly joined, airtight and smoothed mesh blending of upwards of thousands of input mesh pieces that overlap in ways Rhino will never Boolean union.

There is no complicated installation of anything since it's all done in Python.

The ZBrush program itself pops up while it works, and is then automatically backgrounded to bring you back to Grasshopper. It keeps running though, for fast iterations with no program startup time.

This is a general toolkit to expose myriad very advanced features of ZBrush into being just another Grasshopper plug-in like the rest.

It works by accepting a Grasshopper mesh and writing it to disk as an OBJ file, then incorporates ZBrush settings for a given command into a text format ZScript file, also written to disk from Python based on Grasshopper inputs, then ZBrush is told to run the script via Windows command line, and the exported OBJ output is read back from disk back into a Rhino Grasshopper mesh, in about a hundred lines of code.

Despite a change in mesh definition in Rhinocommon from version 5 to 6, I made it work on both versions.

So far this is only one command, the newly improved mesh Boolean union. It gives quad meshes, but they still look healthy when quickly triangulated in Rhino (as seen on top, above).

The ZBrush ZRemesher is utterly astounding in ability to transform any mesh into a direction following, error free quad mesh that can be converted to NURBS actually, via T-Splines smooth mode. That will be the next port to Grasshopper. I hope architects pick up on this more orderly manner of patterning surfaces than the alien slime of random point Voronoi.

Commercial software has the best code, not open source stuff, so far, so this is serious work to bring world class tools into Grasshopper where we can rapidly prototype computational strategies.

Here is a thread with several examples of ZBrush Boolean union remeshing applied to 3D trusses, compared to both IntraLattice and marching cubes:

http://www.grasshopper3d.com/forum/topics/custom-unit-cell-bug-in-i...

The same strategy of generating script files I used to port OpenFlipper, here, for triangle remeshing, which can now be combined with ZBrush Boolean unions of arbitrary assemblies of mesh units:

http://www.grasshopper3d.com/forum/topics/best-uniform-remesher-for...

UPDATE: I revamped the workflow so now components feed raw ZScript into a sequencer. Then only a single ZScript is assembled and sent to ZBrush so Python never gets ahead of ZBrush (!):

It is easy to DIY roll your own now: