Hi jki, re: very slow extrude - over here it's sluggish but still workable, it takes maybe a second or so for each step.

The change in behavior from v2 is because of the switch to the asynchronous calculation method - because the thing you're extruding is an edge that belongs to a larger solid, it's actually the entire solid that gets bundled up and sent to the worker process where the actual geometry creation work is done. It's that whole solid transmission time that is causing the extra sluggishness. If you duplicate that edge as a standalone curve by doing Ctrl+C / Ctrl+V on it, then when you extrude that independent curve you should see it behave much more quickly.

Maybe in the future I can speed this up by making it possible for certain commands to request that sub-objects are sent over as individual pieces rather than the full solid going over. Right now an edge selection transfers the entire solid so that things like fillet that will be working on other pieces of the solid instead of just the edge curve geometry alone will be able to do things properly.

Or I guess probably a better fix overall would be to make the solid just transfer into the worker process one time and keep a hold of it rather than getting transmitted freshly for each individual calculation...

But yeah this case of a kind of big solid where you're extruding a simple piece of it doesn't work very efficiently in the asynchronous way - if you were to make a highly complex set of curves with say 50 curves nested inside of each other and then tried to extrude that, you'd then see the reason why it's changed from v2 behavior, because v2 would just freeze everything on every mouse move since the main thread would be busy doing a bunch of calculations instead of doing things like updating the UI.

- Michael