Talk:MMC2: Difference between revisions

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(Created page with "I read carefully the operation of the PPU rendering and sprite evaluation, and it seems to me that you could use the sprites to adjust the CHR latch per scanlines (for example...")
 
(MMC2 sprite-triggered)
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== Sprite Splits ==
I read carefully the operation of the PPU rendering and sprite evaluation, and it seems to me that you could use the sprites to adjust the CHR latch per scanlines (for example, make a sprite $FE and one line down $FD (if after the first one in the OAM) might make a single scanline to use the other bank). Is this correct? --[[User:Zzo38|Zzo38]] ([[User talk:Zzo38|talk]]) 11:07, 16 June 2013 (MDT)
I read carefully the operation of the PPU rendering and sprite evaluation, and it seems to me that you could use the sprites to adjust the CHR latch per scanlines (for example, make a sprite $FE and one line down $FD (if after the first one in the OAM) might make a single scanline to use the other bank). Is this correct? --[[User:Zzo38|Zzo38]] ([[User talk:Zzo38|talk]]) 11:07, 16 June 2013 (MDT)
: Yes, this could work. As you suggest, if you're willing to use sprites from the same pattern table as the background tiles you can do no-CPU-time raster effects. But that's also a big downside. I'm a little skeptical that the inclusion of two switchable banks is particularly useful, given how few pixels all the sprites can cover (using 8x16 sprites, only 14% of the screen). Maybe if you want to clip more than two sprites vertically on the same line, since currently the only solution is overlaying a sprite with another transparent sprite. —[[User:Lidnariq|Lidnariq]] ([[User talk:Lidnariq|talk]]) 11:37, 16 June 2013 (MDT)

Revision as of 17:37, 16 June 2013

Sprite Splits

I read carefully the operation of the PPU rendering and sprite evaluation, and it seems to me that you could use the sprites to adjust the CHR latch per scanlines (for example, make a sprite $FE and one line down $FD (if after the first one in the OAM) might make a single scanline to use the other bank). Is this correct? --Zzo38 (talk) 11:07, 16 June 2013 (MDT)

Yes, this could work. As you suggest, if you're willing to use sprites from the same pattern table as the background tiles you can do no-CPU-time raster effects. But that's also a big downside. I'm a little skeptical that the inclusion of two switchable banks is particularly useful, given how few pixels all the sprites can cover (using 8x16 sprites, only 14% of the screen). Maybe if you want to clip more than two sprites vertically on the same line, since currently the only solution is overlaying a sprite with another transparent sprite. —Lidnariq (talk) 11:37, 16 June 2013 (MDT)