Does Jurassic Park use pseudo high-res mode?

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dougeff
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Re: Does Jurassic Park use pseudo high-res mode?

Post by dougeff »

clearly looks like there's semi-transparent ghosts passing over semi-transparent ghosts
you are correct, but it's not like modern software where there is an alpha channel.

(I'm sorry I don't have the time to play through the game to get screen caps of the layers, so this is just my interpretation)

The layer with the ghost sprites... they are in front of and behind each other...(normal behavior for sprites)... but I believe that the center of each ghost is transparent pixels, which is how they seem to blend with each other.

on further inspection of the video, the ghosts do not blend at all with each other. They don't seem to have transparent pixels inside.
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Re: Does Jurassic Park use pseudo high-res mode?

Post by Pokun »

Did you have official RGB cables for SNES in France? I'm told even French NES came with composite cable in the box, that was definitely not the case in Sweden. We got the exact same grey RF-switch with both the NES and SNES, the composite cable were sold separately and RGB cables were non-existent. The N64 was the first Nintendo console that came with a composite cable (and it doesn't have an internal RF-modulator anyway).

SCART is a French thing isn't it? So it's not surprising that French TV-sets put SCART on them early on in the '70s. I suppose it has something to do with the SECAM thing.


rainwarrior wrote: Mon Jun 27, 2022 9:58 pm
Pokun wrote: Mon Jun 27, 2022 5:49 pmI'm basically asking if you can use colour math effects on more than one BG layer at the same time and without them affecting each other. Kirby 3 may have transparent water on the midground (which is BG 1 or 2 I guess) and also a transparent foreground with falling petals, bushes, rocks and other stuff (which I guess is BG 3) at the same time. I don't know if this is the case, nor have I checked if it actually uses two transparent BG layers at the same time.
If "same time" is on different scanlines, yes you can do it. You can basically rearrange the whole setup on every scanline. However, on the same scanline, you can't. There is only one blend step, so there isn't a way to get a second blend on top of the first one...
......
It's a pretty minor ability, as there's many other ways to accomplish similar things, and we don't have any examples of any game actually doing this, as far as I know, but it's a marginal exception to the rule of only being able to do one blend step, as long as you can accept the pseudo-hires compromise.
By the "same time" I indeed mean the same scanline. I know that you can mix all sorts of PPU modes on the same frame with raster effects as long as you can fit all the changes in the HDMA.
But it sounds like you can't have both semi-transparent water layer and a separate semi-transparent fog/foreground layer overlaying it. Wouldn't that explain why Kirby 3 uses a separate method for semi-transparency?
I don't get how COLDATA would help with semi-transparency though, if all it can do is solid colors and gradients if applied gradually.
Nevermind, I just checked a longplay and it looks like the water is part of the foreground using the same grill-pattern dithering as all other foregrounds, it's just not parallax (or at least not by much). Now I understand why you were confused by my question.

Maybe the dithering is just an aesthetic choice they made. Kirby 3 is using highly refined aesthetics, similar to Yoshi Island, so the imperfect semi-transparency of the dithering might just be deliberate. Just my random thoughts.

Since sprites also can participate in colour math, I guess those ghosts in Prehistoric Man just uses the same blend as the background. I can't tell if they are truly separate or blend together in that video, but Inceptional is right that it looks very good in this case.
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Re: Does Jurassic Park use pseudo high-res mode?

Post by turboxray »

Pokun wrote: Mon Jun 27, 2022 4:05 pm If you do get one, make sure to get PAL SNES controllers as well because NTSC controllers doesn't work (the opposite isn't true though).
Ohh.. thanks! I did not know that.

As far as RGB, I remember EGM and other NA/US magazines talking about RGB and which consoles supported it (and the difference in quality).. during the 16bit era.
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dougeff
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Re: Does Jurassic Park use pseudo high-res mode?

Post by dougeff »

Screenshot_20220628-113816_YouTube.jpg
Here is 2 ghost crossing, the right one is in front of the left one, you can clearly see the right ghost's pixels without any blending with the other ghost.
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rainwarrior
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Re: Does Jurassic Park use pseudo high-res mode?

Post by rainwarrior »

Prehistorik Man has a level select cheat code. It's pretty easy to go there and take a look.

From top to bottom: main screen, sub screen, output.
prehistoric_man_main_sub_blend_(additive).png
The main screen is just BG3 + OBJ. The sub screen is just BG1/BG2 for the background. It's an additive blend that puts these two screens together to make the output.

As you can see, the ghosts do not blend with each other or the fog, they're just opaque sprites on the main screen layer. That whole layer gets blended with the background (additive) on the subscreen.

Also, you can see how the main character sprites on the main screen are exempt, because sprites using palette 0-3 on the main screen will always bypass colour math. (If we swapped the main and sub-screen for this example, the main character would also blend.)

Finally, something I should point out that's not seen in this picture. Unlike 50% blending, additive blend gives you ways to "fade" the blend in and out. The ghost characters have palettes that fade to darker and lighter to make them fade in and out. You can fade something out completely by making its palette black.

Additive blending is how the party blinks and fade out during summons in Final Fantasy VI. (Try using the , and . keys on YouTube to step frame by frame. You can spot the exact moment where the characters switch to additive blending.)
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rainwarrior
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Re: Does Jurassic Park use pseudo high-res mode?

Post by rainwarrior »

Zonomi wrote: Tue Jun 28, 2022 2:19 amWell, everyone in France who owned a SNES could benefit from RGB output. :D
France had access to RGB earlier than many other places due to the proliferation of SCART (and similarly JP21 in Japan). However, SCART is a multi-signal cable, and in recent discussions about this topic, as far as anyone's demonstrated, Nintendo only ever sold composite-over-scart cables for the SNES, and never RGB ones. (Edit: Zonomi clarifies that they indeed did use it for SNES in France below.)

At some later point, RGB-over-scart cables for SNES became easily available through third parties. I'm sure stuff like this was commonly available in France long before retro enthusiasts in North America eventually started using SCART (e.g. we now see it often in OSSC, Retrotink, Framemeister), but I don't believe RGB-over-scart was common at all for SNES anywhere in the world at the time Jurassic Park came out? (Edit: except France??)

If you had a different experience, I'd love to hear about it, but every single official SNES SCART adapter I've seen was composite-over-SCART, either sold separately, or packaged with the console.
Pokun wrote: Tue Jun 28, 2022 8:37 amMaybe the dithering is just an aesthetic choice they made. Kirby 3 is using highly refined aesthetics, similar to Yoshi Island, so the imperfect semi-transparency of the dithering might just be deliberate. Just my random thoughts.
I don't think it was considered to be dithering at all by its developers. I think from their view, the "hires" mode looked like 50% blend. The way it looks dithered is something new we imposed on it retroactively with the migration toward RGB. (...and retroactively I do think the RGB striping looks kinda cute and novel for this game.)
Last edited by rainwarrior on Wed Jun 29, 2022 12:56 pm, edited 2 times in total.
bocchi
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Re: Does Jurassic Park use pseudo high-res mode?

Post by bocchi »

You don't need RGB to see that there is dithering. S-Video will do just fine. There seems to be a myth that S-video is some kind of in-between composite and RGB in sharpness. In fact it's just as sharp as RGB in the luma part and it's very hard to notice the reduced chroma resolution. The only way I can tell the difference between RGB and S-video is that the colors aren't as saturated, in particular the reds.
I think S-video cables were readily available back in the day.
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Re: Does Jurassic Park use pseudo high-res mode?

Post by iNCEPTIONAL »

dougeff wrote: Tue Jun 28, 2022 8:40 am Screenshot_20220628-113816_YouTube.jpg

Here is 2 ghost crossing, the right one is in front of the left one, you can clearly see the right ghost's pixels without any blending with the other ghost.
Well, however it works on a technical level, I like the effect and it works for me on a visual level. So, if this is what people mean when they say SNES can't have semi-transparency over semi-transparency and the like, it's not going to stop me using it to try to have say my ship's semi-transparent shadow on top of the semi-transparent water, however it's done. :D
Last edited by iNCEPTIONAL on Tue Jun 28, 2022 11:34 am, edited 2 times in total.
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Re: Does Jurassic Park use pseudo high-res mode?

Post by Dwedit »

You get one or the other, not both. Use checkerboard dithering for the shadow instead.
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Re: Does Jurassic Park use pseudo high-res mode?

Post by iNCEPTIONAL »

Dwedit wrote: Tue Jun 28, 2022 11:04 am You get one or the other, not both. Use checkerboard dithering for the shadow instead.
Well, again, maybe on some technical level but not always on a visual level based on the example I linked above from Prehistoric Man. So, rather than just accept someone tell me it "doesn't work" and then not even try it (despite literally having an example that tells me the exact opposite, at least in terms of the effect I'm after visually), I think I'll actually try it first and see for myself how it looks with my own eyes. Because how it looks with my own eyes is all the ultimately really matters to me. And if it looks worse than dithering then I'll either use dithering or just not have the shadows at all. But I'll tell you this for free: That effect above looks far better than any attempt at doing the same thing via checkerboard dithering that I've ever seen. If that's the "wrong" way to do it then I'm happy to be wrong and have some cool looking semi-transparency.
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Re: Does Jurassic Park use pseudo high-res mode?

Post by rainwarrior »

bocchi wrote: Tue Jun 28, 2022 10:39 amI think S-video cables were readily available back in the day.
I don't believe Nintendo ever sold an s-video cable for SNES either, though. For SNES, all I've been able to find evidence of is RF switch, composite, and composite-SCART.

It is quite easy to get third party ones now. Back in the day of Jurassic Park? I really don't think it was.

Back only 20 years ago, though, I think maybe yes. S-Video probably peaked around 2000-2005, and around that time I do believe Nintendo was offering S-video AV-multi cables for separate purchase. I think the Gamecube's manual is the first of their consoles to acknowledge S-video. Though even as late as the Wii they still only shipped with composite and composite-over-SCART.

Throughout the whole lifespan of the SNES, the capability was there, for anyone who had the knowledge to wire up their own cable for RGB or S-Video. People always could, but I really don't think many at all did. I suspect it was maybe another decade before there was a relevant popular mass-market connector, and even by then I think the audience largely did not care about the difference and stuck to the "default" of composite. S-VHS was a flop because it just wasn't a compelling difference to the average consumer. It became a lot more important when HD TVs eventually took over.

I'm open to the idea that there was some market where something better than composite really caught on for SNES during its lifetime, if you wanna present a case for it, but with the topic question being "why did Jurassic Park do this" I feel the state of the market at that specific time is very relevant.


Kirby 3? I dunno, maybe that's just late enough that its developers might have thought about RGB or S-Video a little bit. To me it's more likely they just didn't. It's was absolutely necessary for them to consider how it looked on composite, because the vast, vast, majority would be using that. Did they think about the RGB (or S-Video) version looking more stripey instead? They could have, but they didn't have to.
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Re: Does Jurassic Park use pseudo high-res mode?

Post by iNCEPTIONAL »

rainwarrior wrote: Tue Jun 28, 2022 9:48 am Prehistorik Man has a level select cheat code. It's pretty easy to go there and take a look.

From top to bottom: main screen, sub screen, output.
prehistoric_man_main_sub_blend_(additive).png

The main screen is just BG3 + OBJ. The sub screen is just BG1/BG2 for the background. It's an additive blend that puts these two screens together to make the output.

As you can see, the ghosts do not blend with each other or the fog, they're just opaque sprites on the main screen layer. That whole layer gets blended with the background (additive) on the subscreen.

Also, you can see how the main character sprites on the main screen are exempt, because sprites using palette 0-3 on the main screen will always bypass colour math. (If we swapped the main and sub-screen for this example, the main character would also blend.)

Finally, something I should point out that's not seen in this picture. Unlike 50% blending, additive blend gives you ways to "fade" the blend in and out. The ghost characters have palettes that fade to darker and lighter to make them fade in and out. You can fade something out completely by making its palette black.

Additive blending is how the party blinks and fade out during summons in Final Fantasy VI. (Try using the , and . keys on YouTube to step frame by frame. You can spot the exact moment where the characters switch to additive blending.)
Well I've just learned something new about controlling moving through a video on YouTube. :-o

Also, dang it, someone somewhere told me you can't fade out to transparent on SNES, but that's clearly not the full truth at all. I blimmin' knew it! One more thing the SNES can do that I would have just deleted from the possibility list if I hadn't now learned otherwise. Much like I probably would never have tried to have two semi-transparent objects and/or layers cross over each other at all if I simply believed most of the documentation online verbatim and didn't see the great example in Prehistoric Man that says you can do exactly that, at least on a visual level (enough to fool the vast majority of people) if not on a purely technical level.

It's lucky I've played hundreds of SNES games and watched about a bazillion SNES videos at this point to check for all these different things myself, or else I might assume the SNES was actually as crappy and limited as most Genesis fanboys would have us all believe it is. :-o

Cheers for that little YouTube tip, by the way.
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Re: Does Jurassic Park use pseudo high-res mode?

Post by Pokun »

I definitely remember the Swedish Nintendo magazine talking about using composite cables with both the NES and the SNES back then, but it wasn't something bundled with the system. Of course on the NES it's just a male-to-male RCA cable.
The N64 came with the composite cable as the only choice packed in, I later started using it with my SNES as well. Maru-chang seems to confirm that a PAL SNES composite cable (SNSP-008) does indeed exist.

Nintendo also did release both S-video (SHVC-009) and RGB cables (SHVC-010) for the SFC but only in Japan as far as we know. The RGB cable is RGB21 which wasn't used as widely as SCART was in Europe (SCART was mandatory on every new TV made after some point in the '80s I think), but did exist on some Japanese TV-sets. Many Japanese computers did use it, so I think it might have been more common on RGB monitors with computer users in mind (since RGB is basically required for 80-collumn modes to be readable).
Japan also got a mono-audio version (SHVC-007) of the composite cable which made sense at the time as most TV-sets didn't have stereo speakers.

rainwarrior wrote: Tue Jun 28, 2022 10:03 am
Pokun wrote: Tue Jun 28, 2022 8:37 amMaybe the dithering is just an aesthetic choice they made. Kirby 3 is using highly refined aesthetics, similar to Yoshi Island, so the imperfect semi-transparency of the dithering might just be deliberate. Just my random thoughts.
I don't think it was considered to be dithering at all by its developers. I think from their view, the "hires" mode looked like 50% blend. The way it looks dithered is something new we imposed on it retroactively with the migration toward RGB. (...and retroactively I do think the RGB striping looks kinda cute and novel for this game.)
The dithering was almost visible in my test with composite. The PVM CRT I used in the test is from the early '90s and the composite cable also did exist back then so it's not technically new things imposed retroactively, but definitely not the main target setup for the developers. Not sure if 1-CHIP came before or after Kirby 3 though.
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Re: Does Jurassic Park use pseudo high-res mode?

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iNCEPTIONAL wrote: Tue Jun 28, 2022 12:08 pm Also, dang it, someone somewhere told me you can't fade out to transparent on SNES, but that's clearly not the full truth at all. I blimmin' knew it! One more thing the SNES can do that I would have just deleted from the possibility list if I hadn't now learned otherwise. Much like I probably would never have tried to have two semi-transparent objects and/or layers cross over each other at all if I simply believed most of the documentation online verbatim and didn't see the great example in Prehistoric Man that says you can do exactly that, at least on a visual level (enough to fool the vast majority of people) if not on a purely technical level.
These fades are Addition / Subtraction based, not alpha based. So while you can reduce the amount of fade by making the palette closer to Black, you will get artifacts compared with real alpha blending.

When doing addition, you can't make anything darker, so no black outlines.
When doing subtraction, you need to take from something that's already bright.

Subtraction will allow you to do transparent water that can fade in and out. Your water is darker than the ground, so you can subtract red and green, leaving behind the blue. But only works on top of brighter objects that have brightness you can take away.

Still can't subtract twice and get a shadow and water at the same time using color math.

Some photo editing tools will let you pick different blend modes, like Add or Subtract modes, so you can see what they look like.
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Re: Does Jurassic Park use pseudo high-res mode?

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Pokun wrote: Tue Jun 28, 2022 1:05 pmNintendo also did release both S-video (SHVC-009) and RGB cables (SHVC-010) for the SFC but only in Japan as far as we know. The RGB cable is RGB21 which wasn't used as widely as SCART was in Europe (SCART was mandatory on every new TV made after some point in the '80s I think), but did exist on some Japanese TV-sets. Many Japanese computers did use it, so I think it might have been more common on RGB monitors with computer users in mind (since RGB is basically required for 80-collumn modes to be readable).
Ah! That's interesting! So they did indeed at least test market RGB and S-Video on the AV-multi in Japan for the SFC. It was always kind of amazing to me that the AV-multi was able to stay the same for so long across so many systems.

Yeah, JP21 for monitors was definitely around. My Sony MSX2 had come with a JP21 cable. (FWIW, I think 80-column is not great but still usable on composite though, at least for black and white... with colour maybe not so much.)
Pokun wrote: Tue Jun 28, 2022 1:05 pmThe dithering was almost visible in my test with composite.
Yeah, it can definitely have an effect that makes it through, though I think a lot of cases it's not discernible at all. Did the developers think the vertical dither was a desirable effect? My feeling is no, but there is room to debate in the absence of authority.

Personally, with Kirby 3 via RGB/emulator I think it looks nice on some scenes where it's occasional foreground, but not so much on the water where it covers a big flat area of the screen. With JP, I think it's only detrimental, but it's not something I would fault them for not considering (or even intentionally disregarding).
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