|
Routines |
| Prev: E929 | Up: Map | Next: E987 |
|
|
||||
 
This routine calculates the horizontal direction and speed of the servant/spell cursor icon, and adds/subtracts it from the sprite's horizontal pixel position.
|
||||
| E958 | LD A,($EB01) | Get sprite horizontal movement speed | ||
| E95B | LD C,A | |||
| E95C | LD A,($EAFD) | Get left/right sprite control value (determine whether the sprite is moving and in which direction) | ||
| E95F | CALL $DFBC | Calculate the new sprite speed/position offset based on direction/speed (returned in H register) | ||
| E962 | LD A,H | Retrieve calculated offset from H register... | ||
| E963 | LD ($EB01),A | ...and store | ||
| E966 | LD A,($EB00) | Get the sprite's current horizontal screen position | ||
| E969 | ADD A,H | Add (or subtract) the offset calculated earlier | ||
| E96A | LD C,A | Temporary store in C register | ||
| E96B | SUB $0C | The left and right play area limits are 12 and 228 respectively. This check forces a NC continue to the following routine (after the JR C) if the movement takes the servant/cursor position beyond the left hand side of the play area (< 12) or past the right hand side (> 228). | ||
| E96D | CP $D8 | |||
| E96F | JR C,$E983 | If the servant/cursor is still within screen limits, skip the next few instructions. | ||
|
Servant/cursor position is at the left or right border or the screen.
|
||||
| E971 | LD A,$00 | Set movement speed to zero to stop dead | ||
| E973 | LD ($EB01),A | |||
| E976 | LD A,($EB00) | Get horizontal pixel position | ||
| E979 | CP $80 | Check which half of the screen it is | ||
| E97B | JR C,$E981 | |||
| E97D | LD C,$E4 | If right hand side, set horizontal pixel position to 228 | ||
| E97F | JR $E983 | |||
| E981 | LD C,$0C | If left hand side, set horizontal pixel position to 12 | ||
|
Store adjusted horizontal pixel position:
|
||||
| E983 | LD A,C | Get calculated horizontal pixel position | ||
| E984 | LD ($EB00),A | ...and store | ||
| Prev: E929 | Up: Map | Next: E987 |