Pardner wrote:I have yet to figure out a good way to make tunnel junctions.
Have you tried triangular brushes? Should work well with Sock's method. Make a block & cut it with the clipper tool into a triangle. (Cut again if you need a true pyramid, to alleviate limitations when moving vetices.) Copy & paste to make multiple pieces. Use vertex manipulation to tweak each piece into position as needed. A very poor example can be noticed in the test map over the doorway, but I hope you get the idea.
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Far better examples can be found in Sock's POM map, although the geometry can be a bit overwhelming. Don't worry about caulked faces not touching behind the scenes. It's ok to be sloppy if nobody can see it anyway. At least, that's obviously been my approach so far.