F-Code "-" is the command for Instant Jump Backwards, same as the previous command except that the jump occurs in the reverse direction. Here I've asked for a backwards jump of 27 frames and the picture number display shows that this action has been performed.

An important feature of the instant jump facility is the use of relative addressing - using the command sends the offset number of frames to the player, not the actual picture number to be displayed. This facilitates the design of map-walking or gallery-walking features where each possible direction of travel is assigned an offset from the current frame number and the instant jump is performed by applying that offset when a move is requested.

This is quicker than interrogating the player for the current frame number and then calculating the new frame number and selecting that frame, which would slow things down very considerably.

Click here to return to using F-Codes with CAV