Sticky bit
The "sticky bit" is one of the per-sprite attributes stored in the Sprite Control Bank 3 (bit 6).
Bit | 15 | 14 | 13 | 12 | 11 | 10 | 9 | 8 | 7 | 6 | 5 | 4 | 3 | 2 | 1 | 0 |
Def | Y position | Sticky bit | ? | Sprite size |
Setting it to 1 makes the corresponding sprite "stick" to the precedent one.
The video hardware will automatically place it 16 to the left of the precedent sprite, use the same Y position, size and vertical shrinking coefficient. Only the horizontal shrinking coefficient is left independant.
Sticky sprites can also be called "driven sprites".