Sweet Home 3d design package does not display properly

(EDIT: this isn’t a whinge about Qubes. Its for anyone who tries to do the same and has trouble in future).

I installed sweethome3d in a debian qube, via apt. Gave it lots of memory (8000 max).

Sweet Home 3D runs, but has strange black-outs of panels at random moments. For example: draw a wall on the grid panel, and the other 3 panels go black, plus the menu blacks out.

Sometimes these missing elements can be recovered by clicking on the black bit where they should be, or mousing over the toolbar.

However, not always the case. For example, trying to set preferences (e.g imperial to metric), the menu dialog box flashes to black and refuses to come back, so you can’t use it.

The effect is the program is largely unusable.

I wonder if it has something to do graphics processing in Qubes? In contrast, I have used FreeCAD before (in a very basic fashion) and it worked.

There are apparently ways to get it running in Fedora, but they are too complex for me.

This machine is an lenovo x230 with 32G memory. EDIT: Qubes 4.1

EDIT: just installed on a backup machine I have (also x230, but less memory) running Lubuntu 22.4.04 and it seems to work just fine there.

You can try to increase the number of vCPU assigned to your qube. Since there is no GPU hardware acceleration and rendering is done using CPU then maybe the default 2 vCPUs is not enough.

That makes sense.

Is there a way of knowing how many vCPUs there are - what’s the upper limit, in other words?

What are the risks of assigning 4 or 8 vCPUs?

There is no upper limit, you can assign more vCPUs than the number of pCPUs available in your system but it’s not recommended:

Ah - there’s the problem for me.

In dom0:

$ nproc --all

So already at the safe limit.

Thanks for your help.