Bug? "Cutter" tool doesn't delete parts of grease pencil where it should

Here is my tool setting …


I am new to grease pencil. Thanks. ^.^

It is a limitation of current algorithm.

Sometimes, we are asking Cutter tool to cut an isolated stroke at boundary described by mouse region.
Sometimes, we are asking it to cut until next intersection.

Here, the issue is that there is a drawn triangle in your selection.
You want to suppress what is next intersection for some segment, that its code tells it to preserve.
If you use an eraser to suppress vertices of this triangle, cutter tool can work on remaining isolated strokes.

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What is “a drawn triangle” you mentioned?

  1. If it is the default cube, I will delete the cube. After I did that, the result is still buggy.

  2. Is it one of the triangles internally generated by splitting the shape that I draw using Cutter? It may create numerical error that omits some of grease pencil deletion? I don’t think so, because the bug is very consistent.

By the way, here are the vertices.


That is the problematic triangle I am talking about.

The simple fact to try to eliminate crossing strokes will not work.

Cutter Tool deletes one segment, stops at intersection and keeps the following segments.
If you use eraser tool to remove all intersections, use of Cutter tool will be satisfying after that.

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zeauro, thanks for your detailed explanation. It means a lot for me.

Is it possible to make cutter tool work as if I use such eraser too?

Is there any hidden tool setting?
Should I write a custom script?

No, there is no hidden setting.

I don’t script a lot. I have no idea how a script could find intersections to erase by itself.
There are probably a lot of Grease Pencil addons, I don’t know about.
I don’t recall one about a cutter tool.

Currently, Grease Pencil is rewritten by developers. In 4.3, that will be third version of Grease Pencil as a serious 2.5D animation tool.
In 4.3 alpha, they improved Cutter tool. Complicated intersections may let less segments remain. One or two.
Counterpart is that is no more able to trim isolated GP strokes.
It is planned to create a Trim Stroke tool for Edit mode. That is not available, yet in alpha.