This routine updates the position, direction and velocity of a jumping character (Berk if entry at 55041 or Drutt if entry via routine at 55023) based upon various conditions (control input, collisions with obstructions and the character's current position, direction and velocity). Register E is loaded (either by this routine, or the called routine at 55196) with a value determined by these conditions. The value in E in turn determines how the character's jump will progress. A given numeric value may result from more than one set of conditions. Possible output values in E are:

Value in E	Description	Routine that generated value
0	Character jumping downwards, no collision	55196
0	Character jumping upwards, no collision	55196
0	Current velocity of character's jump is at least 4 and back, left and right (control input) bits are reset	55196
1	Character landed on floor / platform and back (control input) bit set	55196
2	Unused	N/A
3	Character's jump velocity less than 4, and back not pressed, i.e. terminate jumping	55196
4	Character has bounced off an obstruction to the right while jumping right	55041
4	Character's jump velocity at least 4 and left (control input) bit set	55196
5	Character has bounced off an obstruction to the left while jumping left	55041
5	Character's jump velocity at least 4 and right (control input) bit set	55196
6	Character has banged his head on something above him	55196
7	Character is Berk, and his left edge is to the left of colliding entity's (class=129) left edge	55196
8	Character is Berk, and he is between left and right edges of colliding entity (129)	55196

Excluding the calls to the routine at 55196, this routine deals with the horizontal component of the jump. The vertical component is handled by the routine at 55196.

Used by the routine at 49010.