Battletoads/Crisisforce vertical parallax. How?

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CrashTest
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Battletoads/Crisisforce vertical parallax. How?

Post by CrashTest »

Any idea how the second level of battle toads or crisis force does its vertical parallax where different columns move at different speeds?

It is as simple as switching character banks each of which has a different scroll amount?

I can see MegaMan 2 uses a clever sprite trick to fake it in its intro sequence.
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Bregalad
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Post by Bregalad »

It is as simple as switching character banks each of which has a different scroll amount?
That, or make an ultra fast routine that upload the tiles in CHRROM (that's what Battletoads does).
I can see MegaMan 2 uses a clever sprite trick to fake it in its intro sequence.
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Post by tomaitheous »

Usually referred to as dynamic tiles.

You either switch out a small section of the name table memory - either by writing to CHR-RAM or using a mapper for CHR-ROM (with something smaller than 8k switchable). For Battletoads, I'm willing to bet the small strips on the side are dynamic tiles and the main section is a normal BG layout/scroll. There are quite a few other games that use the dynamic tile method.
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Post by tepples »

I seem to remember reading that a lot of PC Engine/TurboGrafx-16 games used dynamic tiles so that its graphics could keep up with what the Megadrive/Genesis was putting out. (PCE had one layer; MD had two.)
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Post by tomaitheous »

I wouldn't say a lot of them do, but there are a number of them. The PCE can do single scanline hsync interrupts (on all 262 actually) and update X/Y regs without restraint. So hsync scrolls are easy to do without dynamic tiles, but some situations call for them - for complex overlapping parts, etc. Otherwise most games used sprites in combination with hsync interrupts for more complex multiscrolls. You'd figure since you can unlimitedly read/write to VRAM during active display on the PCE, there would be more instances of dynamic tiles.
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Post by strat »

So the columns on the side are actually frames of animation that fake scrolling? Maybe that's how Harmony of Dissonance on GBA had five scrolling planes in one room.
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Post by BMF54123 »

strat wrote:So the columns on the side are actually frames of animation that fake scrolling? Maybe that's how Harmony of Dissonance on GBA had five scrolling planes in one room.
It's more likely that they used sprites in that case, since the GBA can support so many. Which area are you talking about, exactly?
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Post by strat »

Oh, I see what they did. It's the corridor above the final boss. BG0 is the status bar and BG3 is split into three with either an hblank or scanline irq. So three active backgrounds looks like five.
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MottZilla
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Re: Battletoads/Crisisforce vertical parallax. How?

Post by MottZilla »

CrashTest wrote:Any idea how the second level of battle toads or crisis force does its vertical parallax where different columns move at different speeds?

It is as simple as switching character banks each of which has a different scroll amount?

I can see MegaMan 2 uses a clever sprite trick to fake it in its intro sequence.
Yes in Crisis Force the trend in level 1 "appears" to scroll vertically being switching a CHR-ROM bank in sequence. It works out looking very cool, but it's a simple trick really. As others have said alot of older games used this trick. I first noticed this trick on Battletoads level 2.
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Re: Battletoads/Crisisforce vertical parallax. How?

Post by jargon »

MottZilla wrote:
CrashTest wrote:Any idea how the second level of battle toads or crisis force does its vertical parallax where different columns move at different speeds?

It is as simple as switching character banks each of which has a different scroll amount?

I can see MegaMan 2 uses a clever sprite trick to fake it in its intro sequence.
Yes in Crisis Force the trend in level 1 "appears" to scroll vertically being switching a CHR-ROM bank in sequence. It works out looking very cool, but it's a simple trick really. As others have said alot of older games used this trick. I first noticed this trick on Battletoads level 2.
MottZilla were you around for me to show you the "Mosaic" demo i made back in 2000 or so?

...where it used faux mode7 to render 3d walls?

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MottZilla
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Post by MottZilla »

No, I never saw that before. And I'm not sure how this relates to the NES or the parallax effect.
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Re: Battletoads/Crisisforce vertical parallax. How?

Post by Dwedit »

jargon wrote: MottZilla were you around for me to show you the "Mosaic" demo i made back in 2000 or so?

...where it used faux mode7 to render 3d walls?

(exponential projection)
That looks like it would be headache inducing!
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d4s
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Post by d4s »

Slightly unrelated, but I just love the way they squeezed out all these effects out of the NES.
Does anybody know who was in charge of programming Battletoads at Rare?
I did a quick search on google, but came up with nothing. The ROM doesn't contain any hints, either.
CartCollector
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Post by CartCollector »

I think Battletoads was made by two British brothers with the last name of Stamper (Chris and Tim, I think?). One was the artist and the other was the programmer. I think they also worked on the Donkey Kong Country series and even developed the pre-rendering method used.
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Post by jargon »

CartCollector wrote:I think Battletoads was made by two British brothers with the last name of Stamper (Chris and Tim, I think?). One was the artist and the other was the programmer. I think they also worked on the Donkey Kong Country series and even developed the pre-rendering method used.
According to the NP comics, there were 3 developers of Battle Toads, whom are named in the comics, and claimed to have turned into the toads when during development of the NES game something goes seriously wrong. :)

i'll get back to you on that once i find the correct issues of Nntendo Power in my collection to confirm if my memories match up with the actual comic series.

if memory serves me Pimple and Rash are the two brothers and Zits is the 3rd developer.

either that or Pimple and Zits are the two brothers and Rash is the 3rd developer.
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