Performance boos due to lower resolution??

Xyb0t

It seems that the yellow text of line at emu startup is very small, and i figured that i was due to a hefty resolution setting... i mean, what is the point of running NES in 1920x1080? (if one does not use shaders, of course). Anyways, i like to run it 'raw', using only 'screen_smooth' enabled.

I use the startup-menu to adjust the resolution. And my challenge is, that i don't really understand the difference between "Default video mode" and "Retroarch render res"?!

If i adjust the "Default video mode", my screen gets cut off, so i guess this is the actual resolution?
If i adjust the "Retroarch render res", the screen looks normal :D

So, for PSX games, i enabled the "enhanced resolution", which should give me 1280x960 instead of 640x480. If i then set the "Retroarch render res" to 1280x960 (instead of 1920x1080 which i suspect that it is by default), shouldn't i experience a little performance boost?

Again, for the NES (with a native resolution at 256x240, having set the "Retroarch render res" to something like 640x480 (because there is no 256x240 or 512x480, and hopefully reducing the distortion a bit compared to selecting 320x240).. would this lead to the Pi having to work a lot less? And in turn maybe more responsive controls?

... am i way off? Does the Pi struggle less when rendering a lower resolution despite having it scale up to HD afterwards? Or is there a better way to do this?

dankcushions

@Xyb0t said in Performance boos due to lower resolution??:

It seems that the yellow text of line at emu startup is very small, and i figured that i was due to a hefty resolution setting... i mean, what is the point of running NES in 1920x1080? (if one does not use shaders, of course).

higher resolution means smaller scaling artefacts. ie, 240 (nes horizontal resolution) does not fit into 1080, so every so often a nes pixel is 4 rather than 5 HD pixels high, if you understand. if you have a game that scrolls up and down you can often see these lines. lower resolution means that these difference are less subtle.

Anyways, i like to run it 'raw', using only 'screen_smooth' enabled.

this smoothing will i guess look uglier at lower resolution (it always looks ugly IMO ;))

I use the startup-menu to adjust the resolution. And my challenge is, that i don't really understand the difference between "Default video mode" and "Retroarch render res"?!

video mode is what is sent to your tv. e.g. a 1080p tv can receive a 640x480 signal, and then it will use a (usually crappy) scaler to stretch it over your screen.

render res is the resolution that the software (retroarch) uses. if this is less than your video mode res then the pi will scale it (actually not bad).

So, for PSX games, i enabled the "enhanced resolution", which should give me 1280x960 instead of 640x480.

afaik 'enhanced resolution' doubles the native resolution. most psx games are 320x240 or something like that, so it typically brings it up to 640x480. i think...

If i then set the "Retroarch render res" to 1280x960 (instead of 1920x1080 which i suspect that it is by default), shouldn't i experience a little performance boost?

no. the pi can do simple scaling in its sleep. i'm told it can help the pi1 and pi0 but not sure why as they have the same gpu. i guess it's at a slower speed and maybe that's enough?

it can help if you are using a shader that runs bad at HD res.. but then it probably looks crappy at lower res.

Rion

I wonder if anyone has tried to feed the output resolution to the lowest possible setting then feed it to a FRAMEMEISTER?

Rion

~~Strike that~~ Open Source Scan Converter (OSSC) is probably a more viability and less expensive option. Sadly the current revision only support RGB-Scart, Component & VGA.

Xyb0t

@dankcushions
I'm pretty sure that the PSX runs natively at 640x480. Nevertheless the distortion/artefacts you mention is my only concern.. and yes i'm not a fan of smoothing either, but it does help a little bit :) And you are right that the smoothing s impaired by the lower resolution... that being said, i'd be willing to run without smoothing if it would help FPS, kinda.. in my imagination, it MUST run faster when retroarch renders 640x480 vs 1920x1280 (and this is before the upscaling, which i bet takes a few CPU cycles aswell).

@Rion
I can try to cram the signal through my Framemeister, but i see no real win to this? The resoluton and every other aspect that Framemeister offers are already covered by the settings in the Pi (i really love my Framemeister for connecting my old C64 machines to a modern, big screen TV... razor sharp picture, no 'prisonbars').

....but if i can live with some artefacts due to odd resolutions and maybe even turn off smoothing completely, wouldn't the lower rendering res result in more FPS, despite the output still being upscaled right before it its the screen?

dankcushions

@Xyb0t said in Performance boos due to lower resolution??:

@dankcushions
I'm pretty sure that the PSX runs natively at 640x480.

nope. it's capable of that but most games are in 320x240. the menus and other static screen can be in higher resolution. there are also some games that use higher resolutions in-game. e.g. http://assemblergames.com/l/threads/list-of-ps1-game-resolutions.39221/

in my imagination, it MUST run faster when retroarch renders 640x480 vs 1920x1280 (and this is before the upscaling, which i bet takes a few CPU cycles aswell).

allegedly with a pi1/0 but surely not for a pi2/3. it's pretty easy to test for yourself, though, but i really doubt there's any scenarios where scaling operations are the bottleneck.

Xyb0t

@dankcushions Well, i understand that scaling might not mean a lot, but rendering i guess will take it's toll??

How can i test for myself? Is there some form of on-screen FPS counter that i can switch on?

dankcushions

@Xyb0t said in Performance boos due to lower resolution??:

@dankcushions Well, i understand that scaling might not mean a lot, but rendering i guess will take it's toll??

they're the same thing. you can't 'render' a NES game in a higher resolution than 240x224 (or whatever it is natively). a higher render resolution just means it's scaled to that by the GPU. same with psx, etc.

(with shaders it becomes different)

How can i test for myself? Is there some form of on-screen FPS counter that i can switch on?

select + x to get to the RGUI. settings > video > show fps counter.