Questions about pseudo high-res and interlace in Modes 0-4

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psycopathicteen
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Re: Questions about pseudo high-res and interlace in Modes 0-4

Post by psycopathicteen »

The only thing I can think of is to make a 12-bit color images with color math.
iNCEPTIONAL

Re: Questions about pseudo high-res and interlace in Modes 0-4

Post by iNCEPTIONAL »

iNCEPTIONAL wrote: Fri May 20, 2022 5:44 pm Here's another good example of pseudo high-res mode being used for semi-transparency on the HUD in Jurassic Park: https://youtu.be/MTKwNEN8FXw?t=74

Although, again, I can't figure out why they didn't just use colour math on the HUD layer to do proper semi-transparency, as in what's the benefit of using the pseudo high-res mode here for that effect instead of the way most other games did it on SNES?

Is there some elusive-obvious reason I'm missing here as to why that HUD couldn't have been done using the normal transparency via colour math?
Anyone got any insight regarding this post?
iNCEPTIONAL

Re: Questions about pseudo high-res and interlace in Modes 0-4

Post by iNCEPTIONAL »

psycopathicteen wrote: Fri May 20, 2022 7:39 pm The only thing I can think of is to make a 12-bit color images with color math.
And would that be more colours than the normal 256 palettized mode? I genuinely dont know what 12-bit colour is in this context.
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rainwarrior
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Re: Questions about pseudo high-res and interlace in Modes 0-4

Post by rainwarrior »

iNCEPTIONAL wrote: Fri May 20, 2022 5:44 pmthe HUD in Jurassic Park...

Is there some elusive-obvious reason I'm missing here as to why that HUD couldn't have been done using the normal transparency via colour math?
As far as I can tell, both Jurassic Park and Kirby 3 could have used colour math 50% blend to do their "pseudo-hires" thing instead.

I don't think you'll find a technical reason for doing it that way instead of the blend feature. It was something they tried, and it worked. On televisions of the time it looked pretty much the same as 50% blend.
psycopathicteen
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Re: Questions about pseudo high-res and interlace in Modes 0-4

Post by psycopathicteen »

8bpp BG1 + 4bpp BG2 = 12bpp = 4096 colors
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rainwarrior
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Re: Questions about pseudo high-res and interlace in Modes 0-4

Post by rainwarrior »

This ROM which we discussed earlier demonstrated the 12-bit colour blend: Elasticity demo
iNCEPTIONAL

Re: Questions about pseudo high-res and interlace in Modes 0-4

Post by iNCEPTIONAL »

psycopathicteen wrote: Fri May 20, 2022 8:07 pm 8bpp BG1 + 4bpp BG2 = 12bpp = 4096 colors
Ah, coolio.

That sounds like it could certainly have potential to me.

Edit: And could the 128 sprite colours also be added to that too, or are they included in that number in the same way I think they are when using all the available colours in normal 256-colour palettized mode?
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