Unable to get Combine Paths to do what I want

Venefyxatu

I'm going through the Tome of Ultimate Mapping and am having some issues with the Complex Rooms part that deals with combining paths and then converting them to a polygon. It seems like I'm not the first one to run into this, but I'm not sure how to get the proposed solution in https://forum.profantasy.com/discussion/comment/93603 to work.

I've managed to simplify the issue down to a set of reproducible steps:

1. Draw a path from left to right, another equally long path below that also from left to right (like the horizontal lines from a square - a snap grid is super helpful here)
2. With the Combine Paths tool, select the top one, then the bottom one and do the necessary flipping to connect them on the right
3. Select the bottom one again - the left side automatically connects nicely.
4. With the LIST tool, you can already see that something's wrong: you have something that looks like a square but there are 8 nodes, overlapping 2 by 2
5. To make it even more visible: use the Node Edit tool to move a node on each corner somewhat out of the "square" - you'll get an interesting squiggle but not a square.

LIST before moving the nodes:

If you follow this exact same procedure again you'll get a different kind of squiggle but that isn't necessarily a clue as to what's going wrong. Here's three attempts:

In the linked thread there is a suggestion to use the Break command followed by DELDUPS but I can't quite find how to do the breaking part properly. I'd also (and probably even more so!) be interested in knowing what I'm doing wrong with Combine Paths, because this seems like a problem that would only get worse as the shapes get more complex.

The end result of this is that, when using Path to Poly you get a polygon with no surface, as the surface lies between the overlapping outline - according to LIST it is now a 2D Polygon with a Solid fill style and still 8 nodes - 2 on each corner of the "square."

An older thread about what looks like the same issue had the original poster resolve the issue by updating CC3+, but since that thread is several years old and I've recently updated to CC3+ 3.97 I don't think I'll find my solution in that direction.

Monsen

Your step 3 is the problem here. You shouldn't be selecting the same line again, it is already part of the combined path. By doing that, you are basically telling the line to combine with itself.

Once you have done 1 & 2, you are ready to use Path to Poly.

Venefyxatu

Oh dear, my stupid appears to be loose. Now that I look at it again, the Tome even specifically mentions that a missing line will be filled in by Path to Poly. And in hindsight it is perfectly obvious that once a line is part of the combined path it doesn't need to be added again.

Thank you for pointing it out!