Drag wrote: ↑
Fri Dec 20, 2019 8:40 pm
I did notice some patterns though, like these are all shooters, a genre which benefits from constant-speed scrolling on one axis (you can stream new tile bitmaps in as it scrolls in a predictable way), and from enemy waves which are groups of one enemy type at a time (only need to have graphics for one type of enemy ship loaded in memory per wave). I don't know if this is what's going on, but these are the first ideas that come to mind.
You'd have to look with an SMS debugger. For Pigarus, it looks more like they're trying to maximize colors on screen by focusing those 15 colors of the sprite palette per group. The BG can use both 16 color BG palette and the 15 color sprite palette, but the sprites are limited to just itself. The SMS also has less overall total 8x8 cells, because the tilemap takes up 64 cell space in vram and SAT (OAM) takes up 8 cells. But BG cells can use sprite cells and has full access to all 512 total cells in VRAM (including the tilemap and sat area). Sprite cells behave more like NES; 256 for 8x8 and 512 if 8x16, and there's a bit in the register settings indicating what half of vram the sprite cells originate (for 8x8 mode).
So little less over all cells, but the BG has access to more cells for more detail (and also includes H/V flipping).
But yeah, my guess would be because they're trying to maximize color Pigarus because the enemies are simple and their should be enough sprite cells for more than one type at a time. To what tokumaru was mentioning; the bells in twinbee have up to 5 different colors for the sprites, so that means they need 5 copies of it in vram (pretty sure they're 16x16 pixels). But then again, that homebrew (and the musha one) looks miles ahead of anything on the NES. Too bad the SMS never got a sound upgrade chip (out side japan with the FM module). That sound chip is rough haha.
Sorry to say, I do appreciate the importance and impressiveness of demos like Bad Apple, but I just don't get that excited over it compared to seeing a game demo. Maybe it's the Sega CD effect.
Yeah, same. It's just a nice indication of vram bandwidth check on the system (remember, it has no mapable chr-rom or chr-ram).