DRD Team

To preface, this may be a function of the OpenGL renderer vs. Software because ZDoom seems to handle all the below behaviors extremely smoothly. Still, it seems incorrect and hopefully it can be fixed. Also note I do not recall experiencing any of these problems on Windows, but it has been a while since I played there and I may not remember.

First, any mode change causes the display to "grab" the underlying/previous graphics and hold them in the window for a moment before updating. Some screenshots in spoiler below, click for fullsize.[spoiler]Scaling DOWN a windowed mode


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Scaling UP a windowed mode
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Now, that's annoying but not too big a deal, but the next problem is worse. Running in fullscreen in less than native resolution does not scale to fit the display. Screenshot in spoiler. [spoiler][/spoiler]I've tested both ZDoom, Chocolate Doom, and Amnesia: The Dark Descent in non-native resolutions and all work 100% properly (supplementary screenshot). Additionally, switching to/from fullscreen also displays the same behavior noted above.[spoiler]Switching out of fullscreen
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Honestly this isn't the end of the world, but it's certainly annoying and makes me enjoy GZDoom on Linux slightly less. Hope it's maybe possible to fix somehow.

As for the first problem, idk, but I'd suspect some kind of conflict with your desktop's composition manager.

The second/third are obviously the problem I've tried to discuss here and continued on ZDoom forum (that's - IIRC - still the latest version of my patch; it should still work, though it needs minor context corrections with the latest 21:9 additions (the content doesn't change, just the context)).

My solution was made to fit my taste, so YMMV.
TBH, an even better solution would be one that changed fov depending on the ratio, instead of forcing 4:3, but I currently lack sufficient understanding of the code to implement such change.

This is outside my capabilities due to lack of hardware to test on so I'm dependent onsomeone with sufficient knowledge to address it.

I kinda figured that would be the answer, unfortunately. I hope you don't mind, but I'm gonna cross-post to the ZDoom forums then; more eyes means more possible Linux users.