Hey Wendy,

Funny you should ask I just finished a little demo using the exact
same trick puyo pop uses:

http://baback.dreamhost.com/sodapop.zip

Its pretty simple actually. Make your tiles the size you want 11x11
or 10x10. Then use the VCOUNT to find out what scan line the GBA is
currently painting, when it gets to an offset of your tile (bubble
size in case of puyo pop) skip the number of blank pixels that are in
the VRAM between that pixel and the next bubble. So if you have 10x10
bubbles at every multiple of 10 scan line you will have to skip 6
pixels to get to the next bubble. (8x8 pixels / tile so the next non-
empty tile is 6 pixels away). Use the REG_BGVOFS for the layer to
skip the lines.

For the horizontal shifts just use two layers and use a shift on the
REG_BGHOFS to make them overlap.

Easiest way to do all this is in an interrupt, but you could put it
in your main loop too if you like.

Hope that helps,
- Baback

--- In gbadev@yahoogroups.com, "Wendy <gadget2032@g...>"
<gadget2032@g...> wrote:
> Looking at puyo puyo, they use 11x11 tiles for their puzzle pieces
> once they have been placed on the game grid. I'm curious how they
do
> this. I was thinking that each piece would actually have to be
16x16,
> but that would leave a 5 pixel transparent area around the graphic
> and the tiles wouldn't be flush next to each other. Anyone have any
> ideas how this is accomplished?