ZDoom

I'm closing this because I honestly have no idea what to do here.

The main problem on Windows with an in-game mode change is that it requires a complete teardown of all video resources and rebuilding them afterward. And that's already causing some problems.

[quote="_mental_"]True fullscreen is so crappy that even Apple recommends to avoid it since ~2010.[/quote]

For once I agree with Apple. Thast applies even on Windows.

That's the same on all 3 platforms. I think what Graf is advocating for is a complete removal of the "fullscreen" mode, i.e. not having a mode change, and not having the application change its behaviour at all versus Windowed mode, other than possibly (?) minimizing itself when losing focus.

[quote="Rachael"]When that happens, Mac will be the only platform without it. (Curse Apple for making Mac OS only work on Mac hardware - at least, without a significant amount of work and dedication that I really have no interest in)[/quote]
Is it about borderless window? Mac version has it and this is the only option for fullscreen on this platform. True fullscreen is so crappy that even Apple recommends to avoid it since ~2010.

About the borderless window: I might have a solution for Linux for that, when I have some time. QEMU does it, so I might be able to loot some code from that to perform the same trick on Linux that I do on Windows.

When that happens, Mac will be the only platform without it. (Curse Apple for making Mac OS only work on Mac hardware - at least, without a significant amount of work and dedication that I really have no interest in)

[quote="Cacodemon345"]. Those who use CRT are probably stuck with old hardware, probably running on OpenGL 2.0 or outdated stuff.[/quote]


A gentle reminder: 6% of our users are actually still using OpenGL 2.x, which means that a real mode switch is the only option to reduce the GPU workload.
Judging from my own experiences with a Geforce 8600 and an Intel HD4000 in the past I'd say once these drop below 2%, we can consider borderless fullscreen the only way to go. I'd really be glad if this godforsaken legacy crap could finally be dumped for good. With my current round of refactoring it has become the major roadblock to doing it in a way that would benefit a new Vulkan backend. While GL2 and GL4.5 can be driven by the same logic, Vulkan can not. And the logic that is needed for GL 2.0 is very suboptimal on GL 3+, so I guess once the stuff got sufficiently separated I'm just going to split off the GL2 part entirely and just leave it alone until it can finally be tossed out.

[quote="_mental_"]I guess for the mentioned target audience Doom loaded in DOSBox is not true vanilla.[/quote]
This isn't true for real hardware-based DOS running on modern hardware.
(Yes, I am talking about running Vanilla DOS-based Doom on modern, real hardware with FreeDOS, but without sound and music :mrgreen:)
It's probably irrelevant anyway.
[quote="Graf Zahl"]Only CRT users would have to turn it on then.[/quote]
There's barely any CRT users in this day and time. Those who use CRT are probably stuck with old hardware, probably running on OpenGL 2.0 or outdated stuff.

As Graf already wrote, OpenGL doesn't have an exclusive mode. Fullscreen in GZDoom is a window covering the entire screen with no decorations. Windows has special handling for this situation where it turns off the DWM - that's the primary reason why you can feel any difference: the input latency is lower and the DWM doesn't miss a frame here and there when turned off.

True fullscreen has a performance benefit over a borderless windowed mode as when in fullscreen the Windows desktop doesn't have to be rendered, so it frees up some resources. Borderless windowed mode, however, because it does render the desktop (as it is really just a window) means that Alt-Tabbing is quicker. I've also read that framerate capping doesn't work in borderless windowed modes, but this may be something on a game-by-game basis, I've not tried it myself. Lastly, if you are in a borderless windowed mode then any Windows notifications will pop-up over the display as and when you get them, but this doesn't happen in fullscreen. You can disable the notifications, though.

For me, I only have one monitor, and I'm using true fullscreen for GZDoom.

[quote="Graf Zahl"]Let's not forget that we still have a significant percentage of users on outdated and slow hardware that cannot use render buffers and then upscale the result. For those setting a lower resolution, even if it provides sub-par visual results may be the only option to play at acceptable frame rates.[/quote]
This is really the only argument for keeping it.

Maybe a solution would be to create a vid_modeswitch boolean cvar that CRT and legacy users could switch on. When it isn't on the Fullscreen setting means "Windowed Fullscreen" with a render buffer of the chosen resolution (like we already have on macOS). That would make GZDoom never do a mode switch unless an user explicitly asked for it.

Edit: thinking about it, if render buffers are off then it could force this boolean to be on. That would make the legacy users never notice the change. Only CRT users would have to turn it on then.

Agreed. I'd still be careful with making too many potentially breaking changes all at once.
Let's not forget that we still have a significant percentage of users on outdated and slow hardware that cannot use render buffers and then upscale the result. For those setting a lower resolution, even if it provides sub-par visual results may be the only option to play at acceptable frame rates.

On the other hand, if all that crappy video mode code could be removed from the backends, things would become a LOT cleaner.

In 2018 forcing a resolution change is so old school. Setups with more than one monitor suffer from it badly.
I guess for the mentioned target audience Doom loaded in DOSBox is not true vanilla. And so, GZDoom is out of scope for them anyway.

I generally agree. What worries me is the backwards tendencies among retro-gamers (e.g. 'only CRTs are decent monitors.', 'I want real scan lines', etc., that makes them stick to old hardware for which the feature actually does have some value. On the other hand, I guess that most of these stick to those specialty ports that seem to be quite popular at Doomworld (but nowhere else... :mrgreen:)

IMHO there is no point to keep real fullscreen. It may be required for some very specific cases like multi-monitor surround (AMD Eyefinity) or 3D glasses setups (NVIDIA 3D Vision). At the moment I have no ability to verify this though.

Sometimes I wonder if there actually should be a real mode switch option anymore. That's a relic from the past that really doesn't play well with modern display hardware.

Is there even any technical difference between a borderless fullscreen window and 'real' fullscreen mode when using the desktop resolution? Unlike Direct3D, OpenGL never was able to enter an exclusive fullscreen mode that gets handled by the system, it always required changing the global system resolution, resulting in re-layouting all other windows.