[Attached feature] Crash when handling large images (beta)

[dev-zzo]

Describe the bug
Degate seems to be unable to handle large images in the latest version with the 'attached' project type.

To Reproduce
Steps to reproduce the behavior:

1. Create a JPEG of 53675x24205 pixels
2. Create a new 'attached' project
3. Use that JPEG as one of the layers
4. Zoom in on the image several times (I counted about 21 click on the + button), at some point the program hangs and crashes

I also tested the half-sized image with the same result.

Expected behavior
There should be no crashing.

Desktop (please complete the following information):

• OS: Windows
• Version: 2.1.0-1

[DorianBDev]

Hi! Thanks for this bug report. I think the issue comes from thread count exhaustion since Degate will try to load image chunks around each position, and at each zoom level. With a big image this might lag behind since loading takes time, and thread count might just explode and make Degate hang/crash.

I'll try to address the issue by changing a bit the loading system, but that might take some time. A possible workaround before landing a fix could be to reduce some parameters to lower values in preferences. I'll try to add some status update soon.

[DorianBDev]

@dev-zzo Could you confirm that Degate was initially loading the image (you were able to see it), but after zooming multiple time it freezes and crash?

[dev-zzo]

With the 'attached' project type, that is the observed behaviour indeed.

[DorianBDev]

A small update on the issue: I might have found an algorithm that'll fix the problem. However it might take some time to experiment and find the best variant. I'll also add a visual indicator when a tile is loading, and make sure even under heavy load Degate will not crash/freeze (in worse case loading will just be very slow). I'm really busy for the end of the year, but I hope I'll land a fix (and new beta version) before the new year.

[DorianBDev]

I should have fixed the issue with 77631e1. I'll do more tests and a bit of cleanup before creating & merging a PR. I regret not having had more time before to tackle the issue (which did not take long to resolve).

[DorianBDev]

A fix landed in the new 2.1.0-beta.2 pre-release. Pre-built binaries are available.