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Graphics > Tile mode to Bitmap mode conversion

#16237 - DiscoStew - Wed Feb 11, 2004 2:06 am

Is it possible to switch from Tile mode to Bitmap mode, and retain everything that was displayed in Tile mode, or would I have to manually copy everything that is displayed (backgrounds, sprites, effects, etc) into some place in memory, switch to bitmap mode, and copy the information over into video memory?
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#16239 - tepples - Wed Feb 11, 2004 2:16 am

Tile and map data in modes 0, 1, and 2 cover VRAM addresses from 0 KB to 64 KB. In bitmap mode 4 or 5, the two pages cover from 0 KB to 40 KB and from 40 KB to 80 KB. You can go from a tile mode to bitmap mode 4 or 5 and back and preserve tile and map data that lies within 0 KB to 40 KB as long as you write only to the bitmap mode's second page.

No, you can't meaningfully go from a tile mode to mode 3 and back without data loss because mode 3 has one page that covers 0 KB to 80 KB.
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