Old game consoles' graphics subsystems had several sprites, or bitmaps that could be moved independently in front of or behind the tile map plane(s). However, they would only accept a small number of sprites on one scanline of the display, causing visible sprite flicker and (worse yet) dropouts in poorly written games. For example, NES will show only the eight frontmost 8-pixel-wide sprites per scanline; Game Boy can show 10. SNES and Neo-Geo (IIRC) can show sixteen 16-pixel-wide sprites; Sega Genesis can reportedly show 20. (Framebuffer-based systems such as PlayStation, Nintendo 64, and PC are limited only by fill rate.) Several techniques have been suggested for working around the limitation:
- Early NES games used only a few sprites, and they patrolled specific areas on screen.
- Capcom games alternate the order of sprite drawing from 0-63 to 63-0 between frames, making flicker present but constant, so it offends less.
- Konami and Pin Eight games start at a random location in the sprite table and increment the sprite address by 17 (instead of 1) every time a sprite is drawn, making flicker pseudo-random and much less noticeable (you can really only see it when huge crowds of sprites are together).