SNES games without disabled overscan (240 lines)

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rainwarrior
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SNES games without disabled overscan (240 lines)

Post by rainwarrior »

So, SNES games normally have a forced blanking at the top and bottom of the picture, reducing it to 224 lines.

It can also do 240 lines (technically 239?) instead, similar to the NES, though on NTSC this dramatically reduces your vblank DMA bandwidth. It also makes some of the larger sprite sizes more difficult to hide "offscreen".

So, very little reason to use it on NTSC in the past, since there's no expectation the end user would even see the blank area. On PAL it wouldn't be much of a compromise at all, assuming your game was exclusive to PAL, but even among PAL-only games I'm having a real hard time finding any examples!

List:
  • Rendering Ranger (NTSC, does some manual blanking)
  • Super Mario World (PAL second revision)
  • Super Mario All Stars (PAL)
  • Super Tetris 2 + Bombliss (NTSC, Japan)
  • Super Tetris 3 (NTSC, Japan)
  • Super Mario Kart (PAL)
  • Tetris & Dr. Mario (NTSC and PAL releases)
  • Tom & Jerry (NTSC and PAL)
  • Yoshi's Cookie (NTSC and PAL)
Edit: Added a few to the list.
Last edited by rainwarrior on Mon May 16, 2022 3:47 pm, edited 2 times in total.
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dougeff
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Re: SNES games without disabled overscan (240 lines)

Post by dougeff »

240 lines (technically 239?)
239. The SNES never draws scanline zero, at the top.

An important point is that HDMA channels go into effect at the end of that 0th (non visible) scanline. If it was rendered, then HDMA effects would not function for that top line... which is why (in my opinion) they decided to disable rendering the top line.
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rainwarrior
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Re: SNES games without disabled overscan (240 lines)

Post by rainwarrior »

Yeah, that's something to be aware of in 224 mode too, since it means a Y scroll of 0 will place the backgrounds 1 row higher vs. the 224 active lines than might be expected.
dougeff wrote: Sun May 15, 2022 5:29 pm...which is why (in my opinion) they decided to disable rendering the top line.
I think it also eliminates the issue NES had with its top line, i.e. sprites had to be fetched on the previous scanline, so none could appear on the first active line.
Last edited by rainwarrior on Sun May 15, 2022 6:33 pm, edited 1 time in total.
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Nikku4211
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Re: SNES games without disabled overscan (240 lines)

Post by Nikku4211 »

With the knowledge that Nintendo doesn't really care about European (and Oceanian) markets, why did they even give the console 239 or 478 scanline modes at all?

It's not like it's a 288 or 576 scanline mode after all, it's going to have that cinematic look on PAL either way.
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Señor Ventura
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Re: SNES games without disabled overscan (240 lines)

Post by Señor Ventura »

Aerofighters and rendering ranger are 256x239 too.
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Re: SNES games without disabled overscan (240 lines)

Post by creaothceann »

Nikku4211 wrote: Sun May 15, 2022 6:26 pm With the knowledge that Nintendo doesn't really care about European (and Oceanian) markets, why did they even give the console 239 or 478 scanline modes at all?
The person leading the development of the NES/SNES might have cared. And Nintendo didn't know if third-party developers would care.
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MSonage
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Re: SNES games without disabled overscan (240 lines)

Post by MSonage »

Rendering Ranger R2 runs at an unusual 256x230. Is just overscan mode with a f-blank covering some of the lowest lines. Which makes this game more impressive as there are some giant animations.
Tom & Jerry runs at 256x239. This game has no dynamic animation at all (not even for the main character), so it's not surprising.
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rainwarrior
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Re: SNES games without disabled overscan (240 lines)

Post by rainwarrior »

Rendering Ranger is curious... It doesn't seem to be doing anything during its manual blank? At least, not in the first level... Maybe it does stuff there later on?

Aero Fighters I can't verify an example in. Where does it enable overscan?
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Nikku4211
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Re: SNES games without disabled overscan (240 lines)

Post by Nikku4211 »

rainwarrior wrote: Mon May 16, 2022 3:47 pm Rendering Ranger is curious... It doesn't seem to be doing anything during its manual blank? At least, not in the first level... Maybe it does stuff there later on?
Even if it was only released in Japan, Rendering Ranger was developed in Germany. Maybe the developers had the PAL instinct to enable overscan before realising the Japanese aren't playing the game letterboxed?
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Re: SNES games without disabled overscan (240 lines)

Post by Pokun »

Nikku4211 wrote: Sun May 15, 2022 6:26 pm With the knowledge that Nintendo doesn't really care about European (and Oceanian) markets, why did they even give the console 239 or 478 scanline modes at all?
Yeah I also thought it was funny that they added extra lines on the PAL SNES PPU even though they didn't on the PAL NES PPU.
They did care for the PAL market though even if it was smaller than Japan and NA, the Game & Watch and NES were both extremely successful already, especially in Scandinavia.
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Nikku4211
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Re: SNES games without disabled overscan (240 lines)

Post by Nikku4211 »

Pokun wrote: Mon May 16, 2022 4:32 pm Yeah I also thought it was funny that they added extra lines on the PAL SNES PPU even though they didn't on the PAL NES PPU.
The PAL SNES PPU in progressive mode doesn't have any more lines than the PAL NES PPU.
The PAL SNES PPU can output in overscan mode, but so can the NTSC SNES PPU, because the bit works on both regions, though at least with PAL you're guaranteed to have underscan anyway so it has a more important purpose there.

The NES normally outputs 240 lines no matter if you're in PAL or in NTSC, even if most NTSC CRTs back in the 20th century didn't show all 240 when PAL CRTs letterboxed it.

It's basically the same vertical resolution as the SNES' progressive overscan mode, which itself displays 239 scanlines, PAL or NTSC.
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93143
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Re: SNES games without disabled overscan (240 lines)

Post by 93143 »

It's more that they realized the NES was wasting precious VBlank time on scanlines the NTSC users would never see, so for SNES they cut them.
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Re: SNES games without disabled overscan (240 lines)

Post by Pokun »

In that case I have misunderstood something. My notes says that the vertical resolution can be set to either 224 or 239 lines on NTSC SFC/SNES (doubled to 448 and 478 in interlace modes) and 239 or 312 lines on PAL SNES (doubled to 478 and 624 in interlace modes). 312 is more than the 240 lines the NES PPU can do. This is incorrect?
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rainwarrior
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Re: SNES games without disabled overscan (240 lines)

Post by rainwarrior »

Yes, it's incorrect, or possibly just ambiguous.

The PAL system does have a lot more blanking lines, but can't do any more active lines than the NTSC one.

(I also think the picture might be vertically offset so it's more centred, unlike the NES, but I'm not sure?)
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Re: SNES games without disabled overscan (240 lines)

Post by 93143 »

Active Display
NES: 240 lines
NTSC SNES: 224 or 239 lines
PAL SNES: 224 or 239 lines

Whole Frame
NTSC NES: 262 lines
NTSC SNES: 262 lines (263 for interlace field 0)
PAL NES: 312 lines
PAL SNES: 312 lines (313 for interlace field 0)
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