How would I go about allowing the user to cut a mesh?

I want the user/player to be able to freely cut an object, into two arbitrary pieces, but I’ve read that it’s not possible to add/remove vertices at runtime? Are there any techniques to accomplish this?

Well since you aren’t able to really allow freely cutting you must make it seem as if you did. :slight_smile: How hard it will be to make depends on how complex shapes you want to support.

Usually if you have couple “hard-coded” ways to split something simple and you have a good algorithm analyzing which one is closest to player input the player is impressed.

You can use the Fruit Ninja technique, make each object out of 2 pieces and then just split then once the user hits them.
There are more advanced techniques but I think it would be really hard if not impossible to implement them in the Blender Game Engine.

Use Python if you want to actually cut the mesh wherever the user hits/decides

An alternate option would be to pre-cut them and bind them together. when the user “hits” the object, then the 2 parts just release the parent-child binding

I recall trying out a unity web demo for cutting objects that gives the exact same result as blender’s bisect tool.
I don’t think that it’s possible in the bge as it relies on creating meshes in real-time, unless someone comes up with some libload-type hacks.

interesting mesh cutting system. it looks like “adding vertices at runtime” to me. cant figure out a concept to fake it and still have the exact same effect in the video. maybe you can find some techniques on how that was achieved, by the developers. or get a glimpse.

i played the game, and you can really cut anything to 2 pieces, or even 80 pieces if you wish. like that one and only feature made a full hit game.