Inkscape crashes when dragging 3D Box tool perspective handle too far

[Tristan Bailey]

This one is a doozy. Easily reproducible bug.

Steps to reproduce:
1. Open a new document in Inkscape.
2. Create a 3D box by clicking on the 3D Box tool, and then clicking and dragging onto the document.
3. Click down and drag the 3D Box perspective point (X-looking handle) in a direction of your choosing.

Note: The direction in which the handle is dragged usually doesn't matter. Whether or not the crash behaviour occurs when dragging in a particular direction, depends upon how the box was created in the first place. If a 3D box was created with three faces, the problem is less likely to occur than a box created with just two faces.

What happens?
Inkscape produces an error message:
"Inscape encountered an internal error and will now close. Automatic backups of unsaved documents were done to the following locations:"

What should happen?
Inkscape should draw a third face when the perspective needs it, and not crash when a face needs to be hidden/removed.

Inkscape version:
Inkscape 0.92.3 (2405546, 2018-03-11)

Operating System:
Windows 8.1 (64-bit)

[mray (mrayyyy)]

Closing because 3D boxes can be created and moved in any direction using the "perspective point".
Can't reproduce this on Inkscape 1.0alpha on Ubuntu.

Closed by: https://gitlab.com/mray

[Tristan Bailey (tristanlbailey)]

Tested and confirmed working in Inkscape 0.92.4. It may well have been fixed without comment.

[Mark B (markeroon)]

I am having this issue with 0.92.4 as well on Linux -- the perspective point has to be "locked" onto a second perspective point for me to trigger the crash.