How do I force 16:9 on a 32:9 monitor for retroarch?

All of my overlays are 16:9 and stretch in 32:9, ruining them. I was hopeful when I upgraded to a super ultra widescreen monitor this would not be an issue. Is there a way to force Retroarch to start full screen in a 16:9 resolution for the interface and then when I start a game continue to remain in 16:9 while utilizing custom frame sizing to fit with bezels? I do not want retroarch to stretch nor do I want to play windowed.


p.s. an even cooler solution would be to have 2x or 3x games running simultaneously in separate bezels within the same retroarch window(full screen borderless) but I doubt that is possible.


If you are interested you could try the Mega Bezel, it can slide the image into the wider area:

Here are some examples from @Duimon"s collection with a 16:9 monitor and a 21:9.




Commando looks really good with that shader! Mega Bezel is definitely in the cards, worked great on my 16:9 monitor–love the work being done there.

I do use a rather custom traditional shader for DOSBox though with a custom PC/Amiga overlay that I haven’t been able to replicate yet in Mega Bezel. I figure there must be able to force overall aspect ratio somewhere in the older say 1.7.3 version.

I figured out how to solve this by adding/changing the following lines in retroarch.cfg:

video_fullscreen_x = “2560” video_fullscreen_y = “1440”


video_fullscreen_x = “1920” video_fullscreen_y = “1080”

Depending on what monitor one has or res they would like the window to be in. I now have a happy dosbox again. :slight_smile:

p.s. Fullscreen mode must be selected, too.

I would love if the HSM Megabezel shader collection could somehow import my VGA and RGB monitor shader presets as well as my bezel because the reflections are amazing.

What kind of presets are these?

You could use your graphics as they are now in the Mega Bezel, you just need to change the background image. You would add these lines to your simple preset:

BackgroundImage = “my Image.jpg” BackgroundVertImage = “my Image.jpg”


They are formatted in the older .cg/.cgp style shaders based on solid12345’s Analog Shader Pack 3.0’s VGA shader with some custom presets added to closer match a VGA monitor from the early 90s. I also modified his Nanao Sharp shader to simulate a Tandy 1000 RGB monitor from the mid to late 80s.

I’m not sure how to share the files directly here. I’ve spent considerable time tweaking them though over the last few years to get them just right.


Ah, yeah the analog shader pack won’t be making it into the Mega Bezel. In the other hand Guest’s shader is extremely versatile, so you might be able to achieve what you want with that.

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You can also try my shader preset pack as a starting point and I’m sure with a few tweaks here and there you can get that 90’s VGA Monitor look and even more!

I used to be an Analog Shader Pack user for years until it became unsupported. I then turned to making my own preset pack almost a year ago after coming across @HyperspaceMadness’s amazing Mega Bezel Reflection Shader and the results speak for themselves!