Animation in the game is handled by a timeout handler function that is called once per timeout interval. In theory, sprite animation becomes faster and smoother as the timeout interval decreases. In practice, this is true only to a point, because the timeout handler function takes a certain amount of time to execute, and when its execution time becomes large relative to the timeout interval, performance suffers. Naturally, a faster CPU can handle a smaller timeout interval. The frame rate is equal to the inverse of the timeout period, the timeout period being the actual length of time from the start of one invocation of the timeout handler function to the next.
Note that, owing to the CPU performance issues described above, the time delay that you set for bomb explosions (see Bomb entry in the Rules section) will actually be slightly more than the nominal value. The deviation from nominal becomes greater as the timeout interval becomes smaller.
By default, the timeout interval is 10 milliseconds, which corresponds to a theoretical maximum frame rate of 100 frames/second. The interval can be set to any integer from 1 to 100 (1000 f/s to 10 f/s).
A player standing in the middle of a square must move a certain number of steps in order to be considered to have entered an adjacent square. The number of steps that a player can move from the middle and still remain in the original square is called the steps per square.
By default, there are 2 steps per square.
It may be set to any integer from
0 to N, such that (2N + 1) is less than or equal to L, where L is
the width in pixels of the tile floor.png, or its height,
whichever is smaller (see
Theme Creation).
For the default tileset, N is 20.
Note that the GUI will allow you to enter any value up to 60, but when you
apply it, the actual value used by the game will be limited to the range of
0 to N.
From the instant that a command is given for a player to move, there is a slight pause before the player's sprite actually starts moving. The duration of this pause is equal to the player movement delay multiplied by the timeout interval (see above). Whenever a player picks up an Extra Speed powerup, the movement delay for that player is decreased by 1, to a minimum of 1.
All players start off a game with the same initial player movement delay, which is 3 by default. The minimum value allowed is 1.