Commodore Amiga A1000, Hardware Reference Manual

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Sprite 0 Sprite 1
Figure 4-12: Placing Sprites Next to Each Other
ATTACHED SPRITES
You can create sprites that have fifteen possible color choices (plus transparent) instead
of three (plus transparent), by "attaching" two sprites. To create attached sprites, you
must:
o Use two channels per sprite, creating two sprites of the same size and located at the
same position.
o Set a bit called ATTACH in the second sprite control word.
The fifteen colors are selected from the full range of color registers available to sprites -
registers 17 through 31. The extra color choices are possible because each pixel contains
four bits instead of only two as in the normal, unattached sprite. Each sprite in the
attached pair contributes two bits to the binary color selector number. For example, if you
are using sprite DMA channels 0 and 1, the high- and low-order color descriptor words for
line 1 in both data structures are combined into line 1 of the attached object.
- Sprite Hardware 117 -