2560x1440p Resolution Possible on MiSTer?

[SegaSnatcher]

Mike Chi recently has been playing around with a 2560x1440p resolution mode in some experimental firmware builds for the Retrotink 5x Pro and he was thinking that the MiSTer might be able to do it using pixel repetition on the HDMI chip to hit that resolution. This resolution would work great for the GBA core with its 3:2 aspect ratio resolution of 240x160p. A perfect 9x scale across both axis giving you 2160x1440p.

[Neocaron]

Don't we have 1440p already ? Mode 13 is 1536p which is actually higher at a 4/3 ratio.
Edit: oh wait I get what you mean, the 1440p that we have is only 1920 by 1440p.

I guess more choices the better!

[SegaSnatcher]

Don't we have 1440p already ? Mode 13 is 1536p which is actually higher at a 4/3 ratio.
Edit: oh wait I get what you mean, the 1440p that we have is only 1920 by 1440p.

I guess more choices the better!

Exactly, unfortunately if you try to scale GBA to hit a full 1440p in the 1920x1440p mode there is not enough horizontal resolution for its 3:2 aspect ratio, so you are forced into using a smaller integer scale with borders around the image in that mode.

[Sigismond0]

2560 is off the table according to Sorg. 1920x1440 is already too high of a pixel clock or something like that.

[SegaSnatcher]

2560 is off the table according to Sorg. 1920x1440 is already too high of a pixel clock or something like that.

Update: I recently talked to Grabulosaure and he is going to look into the pixel repetition method on the HDMI chip. He said if he can get it to work and resources are low it might be worth adding.

[FoxbatStargazer]

You could actually try 2160x1440 (with reduced blanking) as a resolution, the pixel clock would be similar to the currently supported 2048x1536 mode. Although, you might be up against the default resolution limit here, but there is an ultrawide 2p GBA fork that greatly expands that.

Pixel doubling also isn't ideal because you are looking at a 9x scale for GBA, meaning it becomes an uneven 4.5 scale on the horizontal axis.

[SegaSnatcher]

You could actually try 2160x1440 (with reduced blanking) as a resolution, the pixel clock would be similar to the currently supported 2048x1536 mode. Although, you might be up against the default resolution limit here, but there is an ultrawide 2p GBA fork that greatly expands that.

Pixel doubling also isn't ideal because you are looking at a 9x scale for GBA, meaning it becomes an uneven 4.5 scale on the horizontal axis.

You would at least be able to get GBA working in 1440p without the need for vertical bars and get proper aspect ratio compared to 1920x1440p mode.

Also, should offer a noticeably sharper image when displayed on a 1440p or 4K display than using 1920x1080p fill mode, since you can turn off vertical interpolation and have more pixels to work with.

WonderSwan core would also benefit with its 224x144p resolution.

[justaguy]

You could actually try 2160x1440 (with reduced blanking) as a resolution, the pixel clock would be similar to the currently supported 2048x1536 mode. Although, you might be up against the default resolution limit here, but there is an ultrawide 2p GBA fork that greatly expands that.

For what it's worth, I've actually done this before--I had to increase the MiSTer framework's horizontal resolution limit from 2048 to 4096 and recompile the GBA core, but other than that it was pretty smooth sailing. Looked pretty nice on my 1440p monitor.

[Insert Disk Two]

It looks like the DE-10 Nano which seems to be an HDMI 1.2a, supports theoretical max of 4.95Gbps.

2560x1440@60hz requires 5.31Gbps....

[SegaSnatcher]

It looks like the DE-10 Nano which seems to be an HDMI 1.2a, supports theoretical max of 4.95Gbps.

2560x1440@60hz requires 5.31Gbps....

Even with the pixel repetition method?

[Insert Disk Two]

It looks like the DE-10 Nano which seems to be an HDMI 1.2a, supports theoretical max of 4.95Gbps.

2560x1440@60hz requires 5.31Gbps....

Even with the pixel repetition method?

No idea - I am quoting something someone said in the FB group basically.

[SegaSnatcher]

Looks like WickerWaka has found some success getting this to work. Obviously more testing needs to be done. Glad to see someone looking into this.

PixelRepitition.JPG (14.04 KiB) Viewed 6530 times

[AmanoJacu]

Looks like WickerWaka has found some success getting this to work. Obviously more testing needs to be done. Glad to see someone looking into this.

PixelRepitition.JPG

I wish this is possible any time soon, a 2560x1440 monitor I use my mister on doesn't like the 1920x1440 resolution.

[SegaSnatcher]

Looks like WickerWaka has found some success getting this to work. Obviously more testing needs to be done. Glad to see someone looking into this.

PixelRepitition.JPG

I wish this is possible any time soon, a 2560x1440 monitor I use my mister on doesn't like the 1920x1440 resolution.

I hope it does too, but there will be work getting filters updated and aspect ratios worked out for this new mode, so we just have to be patient. It might also help some LG C2 users who are having lag issues with the 1920x1440p mode.

[FoxbatStargazer]

Is this "pixel doubling" method more like 2560x720p and they just repeat every line a second time as they go? Sort of like a scandoubler applied after scaling.

[SegaSnatcher]

Is this "pixel doubling" method more like 2560x720p and they just repeat every line a second time as they go? Sort of like a scandoubler applied after scaling.

It's actually 1280x1440p and then you pixel repeat to achieve 2560x1440p.

[GeoNeo]

https://discord.com/channels/6479093974 ... 1828913183

Test build with 2560x1440p HDMI pixel repetition.

[marquisor]

For me I tried a various of modelines for 2560x1440 and also 1920x1440. NP for my monitor it's ultrasharp, as it's his native vertical resolution,m horizontally I can set it to correct aspect, so it's also Integer.

But I only get a maximum of about 47 or rather 47.5 Hz of vertical refresh rate out of the MiSTer?? Or 47.5 FPS? Not exactly sure, was some weeks ago.