SPRITE TO SPRITE COLLISIONS

Sprite to sprite collisions are recognized by the computer, or flagged, in the sprite to sprite collision register at location 53278 ($D01E in HEX) in the VIC-II chip control register. Each sprite has a bit in this register. If that bit is a 1, then that sprite is involved in a collision. The bits in this register will remain set until read (PEEKed). Once read, the register is automatically cleared, so it is a good idea to save the value in a variable until you are finished with it.

NOTE: Collisions can take place even when the sprites are off screen.

SPRITE TO DATA COLLISIONS

Sprite to data collisions are detected in the sprite to data collision register at location 53279 ($D01F in HEX) of the VIC-II chip control register.

Each sprite has a bit in this register. If that bit is a 1, then that sprite is involved in a collision. The bits in this register remain set until read (PEEKed). Once read, the register is automatically cleared, so it is a good idea to save the value in a variable until you are finished with it.

NOTE: MULTI-COLOR data 01 is considered transparent for collisions, even though it shows up on the screen. When setting up a background screen, it is a good idea to make everything that should not cause a collision 01 in multi-color mode.