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Progressive hires test demo?

rorirub - Jun 5, 2007

		rorirub		Jun 5, 2007
			Reading through the tech docs, it seems that the Saturn can do progressive hi-res (commercial games like VF2 used interlaced). But, no commercial games ever used progressive hires, possibly because you needed special EDTV cables for it to work right. Does anybody have at least a tech demo which uses any of the hires modes? If not, can somebody code one? It would need some kind of left-right scroll at the very least, so its possible to see if any interlacing is done in it or not.

		Omni		Jun 5, 2007
			The 2006 Saturn Coding Contest (click_here)... has one very intriguing submission that is a demoscene-type program that runs in Saturn hi-res. It only works with RGB/VGA cables for Saturn though, so I can't try it myself...perhaps that's what you're looking for. I am curious as to where to obtain such a cable for the Saturn...I was under the impression that you'd have to roll your own... CORRECTION: Apparently it also runs in interlaced too, so perhaps I will get a chance to view it after all.

		vbt		Jun 6, 2007
			I've lost the picture but when I tried to display the RGB/High res version of the nice rotozoom demo, the picture vas displayed twice on my TV but I used the Scart cable with my TV in RGB mode.

cgfm2

Jun 7, 2007

		rorirub said:
		Reading through the tech docs, it seems that the Saturn can do progressive hi-res (commercial games like VF2 used interlaced). But, no commercial games ever used progressive hires, possibly because you needed special EDTV cables for it to work right. Does anybody have at least a tech demo which uses any of the hires modes? If not, can somebody code one? It would need some kind of left-right scroll at the very least, so its possible to see if any interlacing is done in it or not.

If you don't mind waiting a bit I'll see if I can get one written for you. The C4 demo I wrote only has the normal display mode enabled, after I got some reports of people not being able to view it I took it out IIRC.

There are actually several varities of the progressive mode; you can have 480 scanlines progressive and either 320/640 or 352/704 pixels horizontally. There's a slight clock speed difference between the two so one is HiVision compatible and the other is EDTV. I don't remember the actual numbers but it's like 31 KHz and 32 KHz; some monitors will only sync to the first one as it's basically VGA equivalent.

		rorirub		Jun 9, 2007
			I don't mind waiting, but, can you add all of the different modes? There are a ton of tech demos for say 32x which cycle through all the display modes, we need something like that for the Saturn. A simple horizontal picture scroll with a fixed text on top if it stating the resolution mode used, that's what I'm imagining. I don't think it would be much hard to cycle through all resolution modes.

cgfm2

Jun 10, 2007

		rorirub said:
		I don't mind waiting, but, can you add all of the different modes? There are a ton of tech demos for say 32x which cycle through all the display modes, we need something like that for the Saturn. A simple horizontal picture scroll with a fixed text on top if it stating the resolution mode used, that's what I'm imagining. I don't think it would be much hard to cycle through all resolution modes.

I'm a little frustrated with my Saturn right now, here's a preliminary version of the program with no horizontal scrolling (sorry). For some reason there is random graphics corruption for some of the 352x??? displays, but it happens infrequently in PAL or NTSC mode. Can't figure it out at the moment.

Anyway, it goes through all the horizontal sizes, all the vertical sizes, normal and interlace modes (I didn't include single density interlace as the video signal is 100% identical to double density interlace), and then the EDTV (VGA/Hi-Vision) 480p modes.

Text alignment is slightly off for the 640/704 EDTV modes. I'm doing what the VDP2 manual says and it's still not right, grrr..

Information about the mode displayed is shown so you know what you are getting. I tested all of them on a multisync monitor and everything looks great, with the Saturn in both PAL and NTSC modes.

If somebody wants to make an ISO from the binary, go for it. I don't know how that's done.

I can add the scrolling picture by using the line scroll table, but I need to figure out the background alignment issue for the EDTV modes first. And the corruption before that. What a mess. But nothing on the Saturn is easy.

		rorirub		Jun 10, 2007
			That's very nice but I don't know how to run binaries, only discs. Also, without some kind of movement on the screen, I can't tell if the picture is interlaced or prog.... thats why I asked for the horizontal scroll background.

cgfm2

Jun 10, 2007

		rorirub said:
		That's very nice but I don't know how to run binaries, only discs.

Oh, OK.

	
	
		
		
			Also, without some kind of movement on the screen, I can't tell if the picture is interlaced or prog.... thats why I asked for the horizontal scroll background.

Yeah, though I suppose it's a moot point without an ISO. :\

dibz

Jun 10, 2007

		cgfm2 said:
		Yeah, though I suppose it's a moot point without an ISO. :\

Here ya go. Seems to work fine in the latest SSF if anything. The first archive is the ISO file, the second archive is the tools needed to build the ISO.

*Note: The IP.BIN file was stolen from the Charles Doty sporting clays demo.