(2023-02-20, 19:51)Thomas Dickerson Wrote: Has anyone tried using the Cloth Physics brush in Blender to form sails? I'm thinking it would be easy enough to export an .obj and then convert the triangles back with a little script. I'm working on a ship with similar mast structure to the Pirates of Barracuda Bay version of the BSB and noticed none of these sails are even unofficially in the parts library yet, nevermind formed.
Okay, so follow-up info on anyone interested in doing this after me:
Blender Cloth Physics modifier in conjunction with animated armatures (to pull the cloth) and collision (to form around the mast itself) works pretty well.
The most important trick is using the linear bending model, instead of the angular bending model.
If you accidentally use the angular bending model, you will find your sails uncontrollably wrinkly no matter how stiff you try to make them.
Linear bending seems to behave more like a nice sheet of paper, which is also similar to the sail fabric Lego uses.
Another useful tip is to use the circle selection tool to set up pretty large vertex groups around the holes (the vertices should be in both your armature group and your pinning group for the cloth simulation), which will hold the corners taut and prevent weird folds as you're placing the sail. Once you have the sail in place, you can animate a Vertex Weight Modifier in conjunction with a mask group to release all of the vertices except the ones directly surrounding the hole, to allow it to take on a natural shape once placed (basically simulating releasing your fingers from the corners).
My final tip is to only model the sail as a single layer of polygons and use the Solidify modifier stacked after the Cloth modifier to actually create the 3D extruded structure *after* the simulation runs.
Here's my WIP on the afore-mentioned rigging: