Homebrew PS1/2 Homebrew game PS1 DVD Logo Demo

[alexfree]

PS1 DVD Logo Demo​

By Alex Free

PS1 DVD Logo Demo is a small demo for the PlayStation 1 console. It essentially demonstrates the following features/functionality:

• Bounces a large 128x74 DVD logo sprite around a screen (of 320x240p resolution) at 60 FPS.
• The DVD logo sprite can randomly change to 1 of 7 different colors each time the logo bounces off of the screen and changes direction.
• When an exact symmetrical corner hit occurs, an ‘exact corner hit counter’ will appear at the top of the screen after a very brief screen flash of white, as well as a message explaining the controls to dismiss said message. Press DPAD-UP on a controller to dismiss it until the next exact symmetrical corner hit occurs, or press DPAD-DOWN to dismiss it forever. The message explaining the controls will automatically disappear in about 30 seconds after first being displayed if you do nothing. If you do press up or down on your controller, the message explaining the controls will disappear along with the ‘exact corner hit counter’.

PS1 DVD Player uses 7 different CLUTs (ColorLookUpTables) to change the appearance of the single DVD logo sprite, using barely any VRAM. This demo also does not use the libgs library, making it “more to the metal” and tiny in size. The HBlank root counter is used to seed the random function for selecting each CLUT/color on screen.

All Japanese and American PS1/PS2 consoles are supported as they have the NTSC video mode. Everything is currently hard-coded to NTSC 320x240 resolution, and the demo will currently not work on PAL consoles in PAL video mode. PAL consoles with an NTSC video mod would also work.

External Links​

• PS1 DVD Logo Demo Homepage
• PS1 DVD Logo Demo GitHub
• Tonyhax International - A recommended boot method to start the demo on any stock console without required a mod chip to be installed.
• Stealth ROM - A recommended boot method to start the demo on SCPH-1000-SCPH-7502 stock consoles without require a mod chip to be installed.

 

[SylverReZ]

Nice job.

 

[KleinesSinchen]

Okay. Next please a software video decoder for MPEG-2 DVD video on CD-R

Just kidding. Nice homebrew!

What will happen if I run it on my PAL consoles?
Works normally → see below

 

[SylverReZ]

Okay. Next please a software video decoder for MPEG-2 DVD video on CD-R

That was already made possible: https://www.psxdev.net/forum/viewtopic.php?t=1317

Post automatically merged: Nov 25, 2022

What will happen if I run it on my PAL consoles?

Haven't tried it out yet, but it should run fine?

 

[KleinesSinchen]

That was already made possible: https://www.psxdev.net/forum/viewtopic.php?t=1317

That VCD MPEG-1 decoder was what I had in mind when jokingly saying MPEG-2 decoder.

It was a nonsense comment I should be ashamed of!
Even if it was somehow magically possible to process DVD-Video style files with the PS1 in software, the drive is limited to 300KB/s which makes this completely impossible. Full quality DVD-video from CD requires at the very least an 8x CD drive.

 

[SylverReZ]

Full quality DVD-video from CD requires at the very least an 8x CD drive.

I don't recommend writing CDs at 8x speed, personally I'd go with 4x for better compatibility.

 

[alexfree]

Okay. Next please a software video decoder for MPEG-2 DVD video on CD-R

Just kidding. Nice homebrew!

What will happen if I run it on my PAL consoles?

Not sure, probably won't work if it is outputting PAL video mode as everything is written for NTSC (game logic and all).

Funny that you say this. When I sent an earlier build to my friend MottZilla (with no context) he said 'I don't think it's working, the DVD never starts playing'.

Thanks for the feedback I hope to get into a game now that I've learned quite a bit doing this demo.

Post automatically merged: Nov 25, 2022

That was already made possible: https://www.psxdev.net/forum/viewtopic.php?t=1317

Post automatically merged: Nov 25, 2022

Haven't tried it out yet, but it should run fine?

That's the wrong MPEG standard.

 

[SylverReZ]

Not sure, probably won't work if it is outputting PAL video mode as everything is written for NTSC (game logic and all).

Funny that you say this. When I sent an earlier build to my friend MottZilla he said 'I don't think it's working, the DVD never starts playing.

Thanks for the feedback I hope to get into a game now that I've learned quite a bit doing this demo.

It would be best if you placed a dummy file onto the disc next time, it would make the PlayStation with a weak laser read the disc better. Anyways, I'll test it with my PAL PS1 and I'll come back with the results.

 

[alexfree]

It would be best if you placed a dummy file onto the disc next time, it would make the PlayStation with a weak laser read the disc better. Anyways, I'll test it with my PAL PS1 and I'll come back with the results.

There are dummy sectors on the end of the image generated by mkpsxiso. I specified that in the mkpsxiso xml file. There isn't an actual file though. They accomplish the same thing.

 

[KleinesSinchen]

Why do I ask stupid questions instead of trying?

The program runs perfectly fine on modchip'ed (PsNee) PAL SCPH-9002.

i do have to mention that my CRT accepts PAL-50, PAL-60 and NTSC signals, so it might depend on the TV (sometimes RGB-Scart works better than simple composite).

 

[SylverReZ]

Can confirm that it 100% works for me.

Post automatically merged: Nov 25, 2022

That's the wrong MPEG standard.

I know that.