Only 64 sprites! - NESdev BBS

Only 64 sprites!
by pulper on 2004-11-12 (#131)

Wait a second here, if the NES only supports 64 sprites, why does its sprite pattern table have room for 256? Are you supposed to reload new patterns for the same sprite variable if you are not going to use the old pattern anymore?

Re: Only 64 sprites!
by Quietust on 2004-11-12 (#132)

pulper wrote:

Wait a second here, if the NES only supports 64 sprites, why does its sprite pattern table have room for 256? Are you supposed to reload new patterns for the same sprite variable if you are not going to use the old pattern anymore?

The sprite pattern table has 256 entries because it's the same size as the background pattern table (where you can use all 256 entries at once). Also, being limited to the same 64 tiles at once would SUCK if you didn't have bankswitching or CHR RAM, so it makes perfect sense that there would be more to choose from. Besides, if you are using 8x16 sprites, that's a total of 128 tiles across BOTH pattern tables.

Short answer - there are 256 tiles because you can CHOOSE which tiles you want to use.

by Memblers on 2004-11-12 (#133)

If you do a mid-frame sprite DMA, there can be more than 64 sprites. But the screen has to be turned off for maybe 5 scanlines or so, there'd be limitations with sorting and positioning, etc. It could be possible though, to use all the sprite tiles in one frame, heheh.