Modal Dialogs in UE4 Linux unresponsive

Branch: Source
Build version: 4.8.1-0

Description:
Basically, anytime a modal dialog pops up, it’s unresponsive to clicks. The window control buttons (min/max/close) as well as any buttons in the dialog’s message area do not respond to any mouse events (click or mouse-over). I can close the window by right-clicking the window button in my task bar and selecting “Close”, but, of course, that simply aborts the action.

OS: Linux Mint 17.1
Video: Nvidia GTX 550TI (v346.72)
CPU: I7

Hey Joel-

Could you give me an example of of which dialog boxes you’re seeing this behavior with? Do you also see the same behavior with other environment distributions such as Ubuntu?

Cheers

I’ve only got Linux Mint to test with, so I can’t confirm any other distro’s performance (though Mint is built on Ubuntu…)

At the moment, I don’t really have a clear example. I haven’t used the Editor enough under Linux to have consistent cases. It’s usually the more simple, Hey-you’re-about-to-do-something-stupid warning messages boxes that have the problem. The next time I encounter a situation, I will be sure to note the steps leading to it and post back to this thread.

In the meantime, I can tell you that some windows don’t trigger it. For example, the message log-type windows (windows with a textbox / tree content view) don’t seem to have the issue - e.g., import / build error log windows, the unsaved changes window…

Anyway, sorry I can’t think of a clear example at the moment. I’ll let you know next time it happens.

49581-ue4_model_dialog.jpg

Here’s an example.

Basically, I had to reboot the system beforeUE4 shut down. So, it gave me the popup window that let me select the meshes / materials that hadn’t been saved for recovery. The window worked fine. However, some of the data couldn’t be recovered, so the dialog in the screen shot popped up.

I shut it down by right-clicking the dialog button in the task bar, at which point, UE4Editor resumed loading…

49583-ue4_model_dialog_2.jpg

Here’s another. Same situation as before. Seemed to be sensitive to mouse-over (I saw the border highlight as I moved into it, anyway), but all of it’s controls are completely unresponsive. I could hide / show it from the screen, but that started to lock up on me a bit eventually and it seemed to block me from switching even to other applications.

Hey Joel-

Was the second case related to source control as well? We will investigate the issue however it will help to know if it only affects windows that are related to using source control or if it is happening in other places as well.

I think you are using Gnome WM. Easy to reproduce. Add matinee and open it. Press play to start PIE. UE4 will ask it has to close the matine window. On Gnome WM it will not respond. Actually it does but the mouse pointer seems to be offset. Move the pointer a bit around the dialog and you will see that the buttons of the dialog will highlight because it thinks it hovers even though it is somewhere else. So that looks like it does not respond.
The pointer position Slate is using in Gnome WM for Modal window is wrong. In Xfce I can’t see that effect neither in KDE

Cengiz (yaakuro)

It happens elsewhere, not just with source control. For example, if I edit a static mesh and change an LOD setting, I can’t close the editor because a popup wants me to confirm the changes. If that happens, I have to kill the UE4Editor process entirely…

I’ll play around with that and see if I can reproduce what you’re saying. That makes sense. I’m using Cinnamon (which is a Gnome fork, if I recall). If I must, I can try switching WM’s, though I’d rather not.

Will post an update when I can get a chance…

Just tested it in the static mesh editor. Checked “Recompute Normals” option and tried to close to bring up the warning dialog. Moving / clicking the mouse randomly over the dialog had no effect, so I don’t know that the offset issue is at play, here.

However, now that Yaakuro has mentioned it, I have seen this offset effect occur. I’ve also noticed that when UE4Editor is in the foreground, switching between applications becomes problematic. That is, I may click on an application in my task bar, but it doesn’t come to the front, though it is the active window…

While I haven’t tried another WM, I’m inclined to think this is an issue related to Cinnamon.

It is a WM issue, I have the same problems in Gnome 3.10 but if I switch to Unity it is fine. Pain in the but as I don’t like unity. But while playing around with UE4 I just switch ti unity, then back to Gnome after.

Ok. So I’m officially answering my own question.

It’s absolutely related to Gnome-based WM’s. I tried KDE and it ran perfectly - better than under Cinnamon.

Guess I’m going to switch my WM…

i have the same issue under Mint 17.2 (cinnamon) with most of the small popup windows like the “Converting or open a copy” dialog if you want to load a old project.