Incorrect behavior of Eraser Tool in Vector Level.

[beeheemooth]

Issue Summary

There are times when the Eraser Tool behaves strangely: it erases the lines not where it's needed, but elsewhere. Usually this happens when the fill disappears in a mysterious way.

Screenshot or Video Reference

Steps to Reproduce

To reproduce this problem, you should be "lucky". Usually, the fill disappears at the places where the vectors forming the closed region intersect, but are several different lines. Most often, the fill disappears when editing vectors. Disappearance of the fill is a common problem, but it is only the tip of the iceberg. The algorithm that calculates the Gap Check lines often produces the following result:

The Gap Check line will change if you add points.

If you try to erase the line in this case, the erasure will occur in another place, where the Gap Check line leads.

System Information

• OpenToonz Version: all
• Operating System: Windows 8.1

[RodneyBaker]

Two year anniversary of this report.
It's not entirely clear how to proceed here other than to suggest users try not to be 'lucky'. :)

[beeheemooth]

Well, let's sing "happy birthday" for now

[RodneyBaker]

Conducting review of open requests/issues...
Recommend the observations of this report be included in a review of the Eraser Tool in v1.8 development cycle with a goal to document any incorrect behavior observed; and as relates to this report, especially during use of vector levels.