FGU hangs after OccluderAdd

[sstarsslayer]

As I've been drawing LOS lines on a single map, FGU has hung a dozen times causing me to force quit each time. It never recovers, if I wait instead of killing the process. It's not about patience. It loses a little bit of my work each time and says something about database restore when I restart but I didn't try to recover the work. I do not get a crash log so this is different than what I've experienced with older versions. I never had frequent crashes or hangs before but maybe it's because this map has more points than usual.
Since I can duplicate this 100% of the time, I decided I'd at least report it.

To reproduce I:
Made a new empty campaign with no extensions or modules
Created a new image, left LOS disabled, and did not put any tokens on the map. (wanted no excuse for it to calculate much of anything)
Add Lots of LOS walls. It starts out very responsive but gets slower and slower and slower.
Now that it is slow, you can click on a spot then move the pointer quickly and it will accidently start and stop a line as if you had clicked twice.
In this laggy state, one can get it to hang almost on demand. Just draw a couple lines by moving the pointer too soon after clicking.
I thought the problem almost always seemed to happen right after I do some undos. However, I have now reproduced several times with just the click followed by rapid pointer move.

MacOS 10.15.4
8-core i9
64GB RAM
Radeon 5500M (w\ 8GB RAM)

eg it crashed drawing a line across the top here:
FGU hangs while drawing occlusion points.png
Attaching logs.

[LordEntrails]

I think this has been reported by others, i.e. that large numbers of occluders cause problems. I suspect it would help the devs if you attached a sample campaign with a map you have done this with. that way they can test as they do development.

[sstarsslayer]

OK, well then just in case they are useful, I'm attaching the file from the moduledb directory with the occlusions I was working on during the last couple of dozen hangs. I'm editing the image named 000_Level2_PC_50px_43W_55H

and I'll also attach a zip of a separate exaggerated test campaign I made which does hang almost immediately when trying to add to the LOS of the only image in the campaign. It's got some restore files in there too from some of the hangs.

[sstarsslayer]

I forgot to mention, each time this hang happens, the FGU CPU & GPU usage drops immediately from high to near 0%, even though the process doesn't close.