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More than 64 sprites per screen?

More than 64 sprites per screen?
by on (#52806)
Teenage mutant ninja turtles fighter (TMNT 4 perhaps) has got a big sized fighter i.e. Hothead.If both the players select hothead then they will occupy a big sprite area on the screen which I feel shuold use more than 64 sprites. Any ideas how this can be achieved? possibly some type of interlacing done within the sprites??

by on (#52807)
No you can't interlace sprites on the NES, unless you want to disable the PPU for for about 5 scanlines in the middle.

by on (#52809)
Does the sprites ever flicker?

32 8x16 sprites could make for a quite big fighter.

by on (#52810)
Anders_A wrote:
Does the sprites ever flicker?


Yes. When both the players are big ones then there's visible flickering.


Anders_A wrote:
32 8x16 sprites could make for a quite big fighter.


well...I did not think of 8x16 sprites. But yes, they may do the trick!
1)How do we tell NES what size of sprite we are using? In the sprite ram we have only 1 byte for the CHR tile index. 8x16 sprite means 2 8x8 tiles in the CHR rom?

by on (#52811)
There are two bits in PPUCTRL ($2000) that specify how sprites shall be rendered. They have three settings:
  1. All sprites are 8x8 pixel sprites, with tiles taken from $0000-$0FFF
  2. All sprites are 8x8 pixel sprites, with tiles taken from $1000-$1FFF
  3. All sprites are 8x16 pixel sprites made of two adjacent tiles, with tiles taken from both pattern tables depending on the least significant bit of each sprite's tile number

Super Mario Bros. uses setting A; Super Mario Bros. 3 uses setting C.

by on (#52813)
In theory you could flicker all the sprites, and have 128 of them, and 16 per scanline. It would just look extremely annoying.

Atari 2600 had 2 sprites, and many games flickered the sprites to put more on screen. But they had the advantage of older TVs having more phosphor persistance, where the pixel on the screen will continue to glow for a good while after it was drawn.

by on (#52814)
Memblers wrote:
Atari 2600 had 2 sprites

Which could be replicated horizontally by a factor of 2 or 3, with the pattern changed by tightly timed code. (It was easier to pull this off than it might sound to NES veterans; a write to one of the registers would halt the CPU until hblank as a side effect, and there wasn't any pesky fraction-of-a-cycle at the end of a line.) A lot of title screens were 3 pairs of replicated sprites. Video Chess used 2 pairs of replicated sprites to draw 4 chess pieces and then flickered them with odd lines of odd sprites and even lines of even sprites in one field and vice versa in the other. (Incidentally, development versions of Video Chess were larger than the 2600's standard 4 KiB ROM window and thus prompted the invention of mappers.)

Quote:
and many games flickered the sprites to put more on screen. But they had the advantage of older TVs having more phosphor persistance

That and no 5-line delay for rewriting OAM, so the 8x1-pixel sprites could be multiplexed up and down as much as they wanted.

But you're right that black-and-white TV phosphors would generally persist more than those of color TVs. In fact, red persisted so long, even in the Super NES era, that Nintendo made the Super Scope insensitive to red light, instead requiring games to have a slight cyan cast over the entire screen.

by on (#52815)
All I can tell is that the intro of Batman looks TERRIBLE and completely retarded on my TV, so I'm against flicker (unless it's for sprites if there's more than 8 on a line).
Flicker doesn't look nearly as bad on emulators with a recent screen.

by on (#52827)
Bregalad wrote:
All I can tell is that the intro of Batman looks TERRIBLE and completely retarded on my TV, so I'm against flicker (unless it's for sprites if there's more than 8 on a line).


Which part is that? How would it look any worse on your TV? Or do you mean PAL 50hz flicker looks worse than NTSC 60hz flicker?

by on (#52852)
I have no NTSC TV, but the intro of batman flickers between a view of gotham city and text in the hope to make one superposed to the other.

Unfortunately, this looks absolutely horrible on my TV and not cool at all. No idea how it looks on a NTSC TV tough, but it looks less terrible on a modern screen.

by on (#52854)
Running Batman on my NTSC NES makes the intro look like crap as well, even if it may be marginally better than the PAL version. I agree that it's quite a bad design choice.

by on (#53232)
Image

the game programers purposly put a block on having both characters as hot head. because of the flickering