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Author Topic: PS1 Resolution Hacks  (Read 3146 times)

Vasid

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PS1 Resolution Hacks
« on: November 30, 2017, 08:44:33 pm »
So I'm interested in making a small hack to Silent Hill and Castlevania SotN. Both of these games when played on original hardware through a framemeister are unplayable due to resolution changes when switching to the menus. I want to stop this resolution change (if this causes issues with the displaying of the menus I'll deal with that when I get to it) and keep the games in 240p. I was wondering how I should go about doing this? I have an original copy of Silent Hill, a modded PS1 that can run burned discs and plenty of discs.

I was thinking my best bet would be to pop the game in a hex editor and search around for the hex code for 480? Honestly I have no idea, but I've messed with hex editors and know a bit of coding so I'm willing to figure out and struggle through what I need to do, any advice on where to start would be much appreciated.
« Last Edit: November 30, 2017, 08:53:32 pm by Vasid »

FAST6191

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Re: PS1 Resolution Hacks
« Reply #1 on: December 01, 2017, 05:42:36 am »
Searching for 480 is not likely to get you anywhere fast.

The PS1 is noted for having an odd approach to graphics compared to other 3d systems, though if your goal is just to downscale some menus it is a reasonable hack to want to do and should not pose too many problems. I don't know what will be done here but you may find the handling code shuffles things down so many pixels and halving that (or halving + accounting for interlacing) causes problems with the display. Should still function (outside of lightgun games it is not like it cares what is showing) but may be off the screen.

http://www.raphnet.net/electronique/psx_adaptor/Playstation.txt

Do a page search for "The GPU is the unit responsible" for the video section start and "·Display area in frame buffer" for more on what you want.

Personally if it is was just for two games and I really wanted hardware I would delight one of the charity shops here and relieve them of one of their many CRT screens but this works too. I don't know if there is anything better than the framemeister out there these days -- every time I go looking it seems like more expensive and about as good as the VGA boxes of years past.

When you say menu are you thinking title screen or 13:37 of https://www.youtube.com/watch?v=yLCLA2uooeo ? For the latter it appears you are spared a single background and that looks like it is drawn up from individual elements which is nice.

paul_met

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Re: PS1 Resolution Hacks
« Reply #2 on: December 01, 2017, 12:16:02 pm »
It is possible to decrease the resolution, but it a bad idea. If you do this, the current picture will no longer fit on the screen. You will get a very cropped picture.

DarioEMeloD

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Re: PS1 Resolution Hacks
« Reply #3 on: December 01, 2017, 12:25:35 pm »
This is what he's talking about, some menus use a really weird native resolution that is afterwards stretched to fullscreen. I assume what he means is making it always stretch.



Vasid

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Re: PS1 Resolution Hacks
« Reply #4 on: December 01, 2017, 07:45:54 pm »
Searching for 480 is not likely to get you anywhere fast.

The PS1 is noted for having an odd approach to graphics compared to other 3d systems, though if your goal is just to downscale some menus it is a reasonable hack to want to do and should not pose too many problems. I don't know what will be done here but you may find the handling code shuffles things down so many pixels and halving that (or halving + accounting for interlacing) causes problems with the display. Should still function (outside of lightgun games it is not like it cares what is showing) but may be off the screen.

http://www.raphnet.net/electronique/psx_adaptor/Playstation.txt

Do a page search for "The GPU is the unit responsible" for the video section start and "·Display area in frame buffer" for more on what you want.

Personally if it is was just for two games and I really wanted hardware I would delight one of the charity shops here and relieve them of one of their many CRT screens but this works too. I don't know if there is anything better than the framemeister out there these days -- every time I go looking it seems like more expensive and about as good as the VGA boxes of years past.

When you say menu are you thinking title screen or 13:37 of https://www.youtube.com/watch?v=yLCLA2uooeo ? For the latter it appears you are spared a single background and that looks like it is drawn up from individual elements which is nice.

Thanks for the link, I'll start digging through it immediately. As for what I'm going for: I'm trying to tweak the Item Menu screen for both games which goes to 480i to stay in 240p.

It is possible to decrease the resolution, but it a bad idea. If you do this, the current picture will no longer fit on the screen. You will get a very cropped picture.

Is that cropping on the bottom part of that picture all it does? If so that's not so bad. Just cutting off a few edges could work. So long as it still functions it would be worth losing a bit of visual fidelity. Also I instantly download No$PSX, posting that image alone is helpful, thanks! Edit: My only question is how did you adjust the resolution? I've been mucking about in No$PSX and tried a few things in my hex editor but I don't think I'm properly understanding what N$PSX is telling me.
« Last Edit: December 01, 2017, 10:05:42 pm by Vasid »

Gemini

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Re: PS1 Resolution Hacks
« Reply #5 on: December 01, 2017, 11:51:15 pm »
You can't simply adjust the resolution and expect the menu to readapt. This isn't like PC games where you switch resolution and it works the same, because PSX games are programmed in a completely different manner. Basically you'd have to extensively hack the code in order to use smaller everything. I guess the only thing that would be a quick fix are 3d objects, since those are dependent on scalable matrices (unlike all 2d elements).
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Vasid

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Re: PS1 Resolution Hacks
« Reply #6 on: December 02, 2017, 02:06:42 am »
You can't simply adjust the resolution and expect the menu to readapt. This isn't like PC games where you switch resolution and it works the same, because PSX games are programmed in a completely different manner. Basically you'd have to extensively hack the code in order to use smaller everything. I guess the only thing that would be a quick fix are 3d objects, since those are dependent on scalable matrices (unlike all 2d elements).
I never said I expected the menu to just work, in fact I said in my initial post that I expect it to cause issues that I'd then deal with, still having menus that obscure some things might not be so bad depending on what they're obscuring. Just look at the Silent Hill menu a few posts up, really all you need to see is the center to select items and the command window to use them and a hint of the status screen to check health (at least that's all I'd need as a pretty experienced Silent Hill 1 player). I'm mainly at the moment just interested in removing the resolution changes then, if that can be done, I'll go from there. Appreciate you commenting given your experience hacking SOTN. Honestly I'm sure SOTN will be the harder of the two as it's menu has a lot more important data so maybe that one will prove impossible.
« Last Edit: December 02, 2017, 02:14:44 am by Vasid »