Here is an example of a fairly typical vector graphic mess where a shape overlaps itself numerous times. This can be very tedious to clean up. The biggest obstacle seems to be that LB will not “snap” to the intersection. It’s not as easy as just inserting a node there and breaking the shape. It seems like it should be just that easy.
Apparently, the best way, currently, is to break apart the shape and tinker from there. Is this ultimately the best solution?
Usually you can grab a node and drag it around to ‘unwind’ the crossing… you also have the curve handles to change curve direction.
Not sure what the expected results need to be…
Yes, that is one option; but it tends to modify the geometry more than desired.
The expected results would be a complete fill of the shapes instead of having voids where they overlap themselves.
I think I just accidently stumbled on a solution though:
If I select the offending shape, duplicate it, select both, and hit “Weld” it very nearly cleans up the whole mess. It might leave a few small artifacts; no biggie.
Does ‘Trim’ in the node editor address your workflow needs or is there a subtlety that I don’t yet see here?
If there’s room for improvement with this process here please let me know.
That’s interesting, it should select the outermost line and remove the inside loops. Clever!
I’ve found ‘Trim’ to be woefully inadequate in this situation. The problem is that there is no node at the intersection and to get things to break cleanly at the intersection you have to select and insert twice. But it won’t ‘snap’ to the intersection.
I found a pseudo-solution, mentioned above, by accident. I will also look at ‘Split Selected Vectors’, but if that requires two shapes to work then it’s a non-starter.
“Trim” inserts a node at the intersection - this is set up almost exactly as your example above:
If it doesn’t work for you, it’d be great if you could submit that file so we could figure out why it’s failing and fix it.
In the meantime, use the Offset tool, and offset by 0. That’s basically all Weld does under the hood, and it eliminates self overlaps.
I’m also curious which version of LightBurn you’re running? It does snap to intersections, but that was added quite recently. Edit: Oooh - It doesn’t snap to self intersections. I’ll have to see if I can add that.
Snapping to self intersections is done for the next update.
I’m running ver. 1.3.00
I’ll play with trim some more when I got a minute.
I had a chance to try this with Trim a few more times and it does work. I did have one instance where it left a gap resulting in an open shape that auto-join could not fix. I had to go looking for it. Keep in mind that I’m new to this and relatively clueless…
If you’re able to reproduce that case we could take the file and investigate.
I noticed today that a self-overlap didn’t automatically join. I suspect the logic assumes you’re trimming shapes that weren’t connected to begin with, but we could extend that easily to join them again if the two “sides” of the trim came from the same shape and the trim point is a self intersection.
A lot of the times it is a shape overlapping itself. I’ll see if I can recreate that.
Here is a snippet of the file I was editing, testing out Trim to get rid of self-overlapping shapes. I’ve circled in red the offending segment.
The other day one of the staff responded to a thread stating that the ability to highlight only the end nodes of an open shape had been implemented. I can’t find that thread… I didn’t see that feature in ver. 1.3.00.
I can’t figure out how to quote a post in these threads. Clue me in?
node-edit-trim-test.lbrn2 (27.6 KB)
Oz, how do you make that kind of GIF explaining images?
We use a tool called ‘SnagIt’ for capturing screen shots and videos, and it has the option to export as a a GIF.
Select the text you want to quote and the option pops up.
That was me. It’s in the ‘Start Points’ tool:
If the shape is non-complex, you get a start arrow and an end point (in red), and that’s it. If the shape is a ‘compound’ shape or discontinuous (malformed), the end points will be much more pronounced, so you can tell at a glance if it’s ‘broken’ or not.
This is working as expected for me:
It doesn’t re-connect the trimmed section (I had to grab / drag / snap them back together), but the trim works.
That’s what I saw, too. I thought the point was to connect them at the intersection; in most cases it seems to. We can live with this, though.
I’ll look at making it automatic if the ‘snip’ happens on a self-intersecting shape.
