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Recently we had a client commission a project from our company that was to be manufactured out of Corian countertop sheet goods and they wanted perfectly mitered corners on all of the parts with no visible seams. Oh and they sent a concept model that had exactly zero right angles between faces. As I sit there mentally tallying all of the potential hours spent manually placing splitting planes or attempting to draw extrusions edge on I gave the sales team my overestimate for a go-away price to avoid the headache. Then the client paid it. So suddenly I was motivated to develop an alternative tool to avoid ever having to sketch a mitered joint ever again. Introducing Miter Warlock.

So imagine you were handed an object like this from a design team and asked to make it out of sheet goods. How would you panelize it? Does your approach scale to an object with hundreds of unique N-gon panels with random angles between every adjacent face?

Well if it does you should probably have told me about it before I wrote this script.

Miter Warlock takes a face or faces as a user input, finds the closest parallel(ish) face on the same part that lies behind that face, and draws a loft between the face pairs to split the parts into perfectly mitered panels. The input geometry can be drafted using whatever tools you desire, the only requirement is that you have some kind of shell-like geometry as a starting point whether that was made using shell, sweeps, 3 extrudes in a trench coat, whatever. There isn't even a requirement that each face in the part be a consistent thickness with the others on the same part. You just can't use b-spline faces for reasons I'll explain in a moment.

Since the resultant bodies are split, Ids are preserved for downstream operations. Don't put hole features in before this tool gets used though, I'm not checking for internal loops yet. Probably the highlight of the tool though is how it handles corner cases. Literal ones. This topological nightmare.

This is where the tool gets its name: loft features in onshape cannot cleanly resolve cases where the number of edges mismatch between loft profiles, and will draw spline faces in places where I need nice clean planar miters. Instead of studying how this problem ought to be solved methodically like a good wizard I started borrowing any available public features that do faceting things to facet my errant spline faces. I settled on Konstantin's Convex Polyhedron script as a faceting function for my script. I think that makes him my patron and my publishing this means I'm contractually bound to owe him a favor. At least I never need to draw a sketch for a miter again.

@MichaelPascoe You should see some of the cursed sheet metal forms I was able to birth into existence when I was testing the waters with the bounds of the scaling operation. If I'm reading the docs correctly these are affine transformations under the hood which is a much larger matrix of possible operations. If they ever expose the other values for me to play with you're gonna see some weird shit out of me.

Assembly mirror is coming — it's surprisingly complicated to do it well, but we think we have a good solution.