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Beginners > GBA: 256 Colours / 256 Unique Tiles ???

#54571 - Tyler Carlissian - Tue Sep 20, 2005 2:43 pm

So, Rotation Backgrounds are limited to 256 Unique Tiles?

Why, instead of 256 8*8 tiles don't we use 256 colours?

The tileset we use is going to be 256 colours anyway, why not create a map pixel by pixel refering to the colour of the pixel rather than referring to a unique tile?

Anyone got any ideas?

I am new to this so my understanding might not be correct about what the GBA does and I realise the answer may simply come back in the form - "that's just the way it works" but i've been wondering about this so was wondering if anyone could shed some light?
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#54584 - poslundc - Tue Sep 20, 2005 5:31 pm

256 8x8 tiles = 16,384 unique pixels, which is greater than 256.

You cannot create a map pixel-by-pixel; you create it tile-by-tile. The tiles can contain whatever pixels you want (8x8 pixels per tile), but you must specify which tiles to use on an 8x8 grid, not a 1x1 grid.

Dan.

#54587 - FluBBa - Tue Sep 20, 2005 5:55 pm

Rotational/scaling backgrounds are supposed to be used like that <-

You use it for "mode7" effects, if you use a tilemaped mode instead of a bitmaped mode you can have a map that is 1024x124 pixels big, in bitmaped mode it would eat up 1MByte of VRAM which you don't have on a GBA.
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