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DS development > 2x ext. rot 256/16 on both main and sub screen?

#126438 - bjoerngiesler - Mon Apr 23, 2007 6:41 am

Hi,

I want to have 2 16bb extended rotation backgrounds that cover the whole screen on both main and sub screens. From DSWiki, I get the impression that's not possible (as there is only one 128K block, VRAM_C, that can be used as sub bg). Is that true, or am I overlooking something?

Thanks a lot!
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#126441 - Lick - Mon Apr 23, 2007 6:52 am

You need two of thse:
Quote:
128 KiB

BG_BMP16_256x256

one for each screen. So it fits?
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#126470 - tepples - Mon Apr 23, 2007 1:38 pm

Unless someone wants to use two layers or use hardware scrolling. I'm not entirely sure what is meant by "2 16bb extended rotation backgrounds that cover the whole screen".
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#126471 - Lick - Mon Apr 23, 2007 2:16 pm

I missed the "2" from the original post. Bjo?rn: I think you can use VRAM_A and VRAM_B for the Main screen, and VRAM_C and VRAM_D for the Sub screen. Although you have to make a special case for VRAM_D, you have to set it to Sprites mode.

Search the forum for the 3D on both screens project. It contains the code to set up eight pieces of 64x64 sprites to emulate a Ext Rot background.
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#126483 - bjoerngiesler - Mon Apr 23, 2007 5:57 pm

Lick wrote:
I missed the "2" from the original post. Bjo?rn: I think you can use VRAM_A and VRAM_B for the Main screen, and VRAM_C and VRAM_D for the Sub screen. Although you have to make a special case for VRAM_D, you have to set it to Sprites mode.

Search the forum for the 3D on both screens project. It contains the code to set up eight pieces of 64x64 sprites to emulate a Ext Rot background.


That was precisely what I meant, thanks. Although I'm not sure I understand the code I found there, but I'll keep trying :-)

EDIT: No, I think that's not what I want -- am I right in assuming that sprites are continuous in sprite memory? I.e. in a 4x3 map of 16bpp 64x64 sprites, the second line from the top would start at VRAM_BASE+2*64, while in a 256x192 extended rot. background it would start at VRAM_BASE+2*256? Hmm, that limits the interchangeability somewhat.
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