Commodore Amiga A2000 - Figure 4-10 Typical Data Structure for Sprite Re-Use

SPRITE DISPLAY LIST
------\ _ Data describing
________________________________ | / the 1st vertical
Increasing |________________________________| | / usage of this
RAM |________________________________| |/ sprite.
memory ________________________________ |
addresses |________________________________| |
|________________________________| |
| _________ |
| _________ |
| _________ |
| ________________________________ |
| |________________________________| |
| |________________________________| |
| -----/
|
| -----\ _ Data describing
| ________________________________ | / the 2nd vertical
| |________________________________| | / usage of this
| |________________________________| |/ sprite. Contents
| ________________________________ | of vertical start
| |________________________________| | word must be at
| |________________________________| | least one video
| _________ | line below actual
| _________ | end of preceding
| _________ | usage.
\|/ ________________________________ |
V |________________________________| |
|________________________________| |\
| \
-----/ \_ End-of-data words
ending the usage
of this sprite.
Figure 4-10: (Typical Data Structure for Sprite Re-use)
The only restrictions on the reuse of sprites during a single display field is that the bottom
line of one usage of a sprite must be separated from the top line of the next usage by at
least one horizontal scan line. This restriction is necessary because only two DMA cycles
per horizontal scan line are allotted to each of the eight channels. The sprite channel
needs the time during the blank line to fetch the control word describing the next usage of
the sprite.
- 114 Sprite Hardware -