Feasibility of a particular graphical effect

[spenoza]

OK, so, I thought of an interesting way to simulate two background layers, but I wonder if it's really feasible. I know you can flicker sprites on and off to get more on a line. Can you flicker background tiles? If you could somehow swap them out quickly enough, and if there was enough VRAM space available, you could create two separate background layers and just rapidly switch between them.

Possible? Impossible? Pointless?

[Tatsujin]

if it is possible, which i don't really know if it is or not, it sure would have the side effect of some nasty constant 30Hz flickering all over the screen. wouldn't it?

[Arkhan Asylum]

It's possible, sure.

Is it practical?  no.

You would have to do alot of very strange setup to where you're almost trying to mimic the Super Grafx through the use of flickering.   

I'd imagine that unless the game ran at a perfect 60fps the whole time, you would see it, and probably get a headache.

[CrackTiger]

Vasteel does this for its scrolling transparency layers.

[OldRover]

Yeah, I was thinking about Vasteel when this was mentioned... it's done in two of the space regions, and one of them even gets the freaky-ass sinewave effect.

[Arkhan Asylum]

lol, That's probably about the only thing you could use it for and have it not look goofy.   

I figured spenoza wanted something for more of a super-layered parallaxy side scroller, as opposed to a repetitively tile'd battle portion of a strategy game that really doesn't have a lot else going on... ;)

[ParanoiaDragon]

Ok, I want 16 fricken layers of parallax, blinkin' like nobody's business, & I want it NOW!  If you ddin't get seizure's, well, now you do!

[spenoza]

Well, I was thinking about the background in that Gameboy shooter, ZAS. It has some 2-layer effects going on in the first level, and it kinda looked like that's what might have been going on. I figure if the Gameboy can pull it off convincingly...

[CrackTiger]

Well, I was thinking about the background in that Gameboy shooter, ZAS. It has some 2-layer effects going on in the first level, and it kinda looked like that's what might have been going on. I figure if the Gameboy can pull it off convincingly...

At least one Gameboy game did do the same effect as Vasteel, even with the only-on-Genesis-TFIII-style swirly wave. My instinct is to say Zelda LA, but it might have been FFLIII.

[Arkhan Asylum]

Well, I was thinking about the background in that Gameboy shooter, ZAS. It has some 2-layer effects going on in the first level, and it kinda looked like that's what might have been going on. I figure if the Gameboy can pull it off convincingly...

So you just want like, a goofy tile update/flicker that gives the sense of layering, but isn't a very exciting layer, basically?


I think the trick would be limited to some pretty basic stuff to the point where it's not really worth doing, given the other things you can do instead to achieve nice visuals.

[Joe Redifer]

Even if it ran at a perfect 60fps, you'd still notice and be annoyed by the flicker. When characters get hit in many games, they flicker at 60fps and you can still notice.

[ccovell]

Well, I was thinking about the background in that Gameboy shooter, ZAS. It has some 2-layer effects going on in the first level, and it kinda looked like that's what might have been going on. I figure if the Gameboy can pull it off convincingly...

Have you seen that level of ZAS on the Super Gameboy?  The effect is totally broken.  Now just imagine that fullscreen on the PCE.  Yuck!

[TurboXray]

Cho Aniki or Ai Cho Aniki does this for one of the levels. But it's more a transparency effect (IIRC it was a water fall BG flickered over something else. Maybe enemies?).