Resolution and performance

[timewalker]

Hi, I’m building myself a tiny all-round emulator station to play on a TV.

I’ve noticed that depending which system or port you start, the TV mode changes. The issue here is that the Pi sets to mode 16, which is 1920×1080@60hz, I don’t have any overscan in this mode. If I then choose for example Quake, then it changes to 4, which is 1280×720@60hz. This mode however gives me overscan so some stuff gets cut off.

Now I tried to fix that by forcing to just stay on the original mode, which works fine. But the issue is, if I do this on every emulator and game port, do I get a performance drop? I’m not sure if the game starts to render on a bigger screen and thus go slower or if it just resizes to full screen without losing any performance.
Also, if there is a performance drop, is there any better way how I can fix the variable overscan on different games?

[Roo]

I have all my emulators set to CEA 16 – 1080p resolution (by pressing x as the emulator loads up from ES) and I don’t notice any performance hit.

[gizmo98]

If you use RetroPie >= 2.5.0 you can use hardware upscaling. Open /opt/retropie/configs/all/retroarch.cfg and set:
video_fullscreen_x = 800
video_fullscreen_y = 450

Now you can enable 1920×1080@60hz and your Pi upscales 800×450 to 1920×1080 for free.

There is also a nice side-effect. You can use shaders with 1920×1080@60hz.

[timewalker]

Thank you gizmo98 for the solution! I’m using the 2.5 BETA and this actually made my emulators like SNES even go faster than before so I think there really is a performance drop if you set the mode to 1080p.

A bit less on topic, even though the video_fullscreen solution fixed the lag, I noticed that the xboxdrv makes emulators like the SNES one lag when using the thumb sticks. I’m using the Daemon init.d method and I can’t seem to find the cause of that. I looked if silent mode isn’t used and tried to add them in the script but it didn’t help at all.

[Roo]

[quote=88016]I noticed that the xboxdrv makes emulators like the SNES one lag when using the thumb sticks[/quote]

There’s a performance hit from using xboxdrv. If it’s too much, the only solution I know of is to just use the default settings (xpad) and deal with the flashing ring :)

[Roo]

[removed]

[timewalker]

While I could live with the flashing ring, on xpad I had problems with thumb sticks.

One example: On Quake, the right stick would get ‘stuck’ so that the camera rotates infinitely to the right. When I move the stick to the right again, it stops. This seems to be fixed with xboxdrv. Is there any setting I missed on xpad/Quake?

[supernashwan]

this is interesting

If you use RetroPie >= 2.5.0 you can use hardware upscaling. Open /opt/retropie/configs/all/retroarch.cfg and set:
video_fullscreen_x = 800
video_fullscreen_y = 450
Now you can enable 1920×1080@60hz and your Pi upscales 800×450 to 1920×1080 for free.

is 800×450 the best resolution to run everything? is there a magic resolution that works for all emulators?

[neighbourhoodnerd]

Basically just consider the fact that all these old consoles were designed to output to old TVs. The resolution output doesn’t need to be very high at all. I’d suggest using that setting on the ALL retroarch config. It’s very unlikely to make anything look worse :)

[gizmo98]

You can use “any” resolution. You can also set 320×240 or 640×480. 720p and 1080p are 16:9 resolutions. So try to set a 16:9 resolution like 800×450. Otherwise a 4:3 render resolution will be streched to your 16:9 screen resolution

[petrockblog]

gizmo – not possible to use this and keep aspect ratio ? perhaps that could be changed and we could use this by default then.

[gizmo98]

I have already a modified retroarch videocore context driver in the pipeline. I had no time to test it because of n64 stuff

[Roo]

I won’t be the default will it? Just pointing out that I don’t think everyone would want that. Hardware upscaling screws up shaders and overlays. I’d rather use those than hardware upscaling. Especially when the emulators seem to run fine at full speed at 1080p

[petrockblog]

well, it’s impossible to please everyone – we try to make the most common set up the default. as can be read, not everyone appreciates us switching the screenmode by default, which was done to try and sort out performance issues – many of the shaders do not perform well at high resolution.

default does not mean you can’t change the behaviour. I have spent a lot of time trying to make stuff more easily configurable.

[timewalker]

I just want to say, after my RetroPie corrupted yet again, I’m now using 2.6. I’m staying at xpad now as I noticed that the Quake problem could be of my sticks being a bit loose.

Anyway, I’m not sure if 1080p gives full performance. I have my Pi overclocked at Turbo and having it on 1080p makes SNES lag at some games. For example, Tetris Attack SNES doesn’t run in full speed when playing – especially on VS. Mode.

Well I can see the reason of changing the TV mode, it doesn’t seem to work perfectly fine. On 1080p, I have no overscan whatsoever but as soon as I change to a different screen, the screen gets cut off. The full screen 800×450 setting seems to do the trick with performance issues however you can see at specific games that there are stretched pixels. My goal isn’t to use any shaders and have everything pixel perfect without the CRT TV designed choices (like green/pink pixels, scanlines, etc).

[Roo]

[quote=88115]well, it’s impossible to please everyone – we try to make the most common set up the default. as can be read, not everyone appreciates us switching the screenmode by default, which was done to try and sort out performance issues – many of the shaders do not perform well at high resolution.

default does not mean you can’t change the behaviour. I have spent a lot of time trying to make stuff more easily configurable.
[/quote]

Sure, processor intensive shaders are never going to work well, but I’ve had a lot of success with Pi2 and the basic shaders, even at 1080p. I never had success finding a decent scanline shader that would work with Pi 1.

You’re right – I don’t really have any opinion over what y’all choose as the default setup. I can always undo any changes that don’t work for me.

[Roo]

[quote=88120]Anyway, I’m not sure if 1080p gives full performance. I have my Pi overclocked at Turbo and having it on 1080p makes SNES lag at some games. For example, Tetris Attack SNES doesn’t run in full speed when playing – especially on VS. Mode.[/quote]

Pi 2 model B? I can’t test Vs mode (I only have one controller) but I run the game at 1080p with a shader and overlay and see no issues at all.

[gizmo98]

@Roo
PI1 benefits from lower resolutions. There is a performance drop if you use resolutions > 720p. You can tune the upscaling behaviour. Raspberry pis linux kernel has eight scaling kernels. There is at least one without blur:
https://github.com/raspberrypi/firmware/issues/104#issuecomment-9585095

[Roo]

@gizmo98
I get that, but I don’t see this project supporting the Pi1 long term. It was just a little too underpowered for what most people seem to want from their retro-gaming machine.

[timewalker]

Right now I’m still using Pi 1 Model B (yes, that old) so that’s why I’m very limited.
I used it for other stuff which got replaced by a Pi 2. Now I’m using the old model for emulation and media center while I’m waiting for another Pi 2 to arrive because I was unhappy with my old media center/emulator station OUYA and want to replace it with that.

[Roo]

I believe you’ll see all your problems go away once you get the Pi2

[Anonymous]

[quote=88121]

Sure, processor intensive shaders are never going to work well, but I’ve had a lot of success with Pi2 and the basic shaders, even at 1080p. I never had success finding a decent scanline shader that would work with Pi 1.

[/quote]
Hi Roo, what shaders are you using with Pi2?
Is crt cgwg shader working or is it still laggy?
Thanks.

[Roo]

Currently I am using NTSC_scalines (or something close to that name, not in front of my Pi right now). It is supposed to be one pass of the multipass NTSC shader, but it works well on its own and gives me the effect I am looking for with good performance.

[dk999]

To jump into the topic:
I’ve set my pi to HDMI group 1 and mode to 4 (720p). I want all my Emulators to stretch the image to 16:9 and have set the configfiles Tod:
Custom_vieport_width = 480
Custom_viewport_height = 640
Aspect Ratio to 1.33 and screen to 16:9 but only some like pocketsnes work and Emulators like picodrive give me fullscreen with master system games but a cropped and smaller image with borders in mega CD games. Where’s the problem? -_-

[gizmo98]

Set video_fullscreen_x and video_fullscreen_y instead of custom_viewport. Comment all other settings. vc context driver does not respect any of these settings.
video_fullscreen_x = 640
video_fullscreen_y = 480

[Roo]

Did you set each emulator as you launch the game by pressing “x” or “m”?

[Anonymous]

[quote=88309]Currently I am using NTSC_scalines (or something close to that name, not in front of my Pi right now). It is supposed to be one pass of the multipass NTSC shader, but it works well on its own and gives me the effect I am looking for with good performance.[/quote]
Thanks, i’ll try it when i get my pi2 ;)

[Author]

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