- Opcode: 0xC2
- Short name: LADER
- Long name: Ladder
Memory layout
| 0xC2 | B1 / B2 | B3 / B4 | X | Y | Z | I | K | A | D | S | |——|———–|———–|—–|—–|—–|—–|—–|—–|—–|—–|
Arguments
- const Bit[4] B1: Bank to retrieve X-coordinate, or zero if X is specified as a literal value.
- const Bit[4] B2: Bank to retrieve Y-coordinate, or zero if Y is specified as a literal value.
- const Bit[4] B3: Bank to retrieve Z-coordinate, or zero if Z is specified as a literal value.
- const Bit[4] B4: Bank to retrieve ID, or zero if I is specified as a literal value.
- const Short X: X-coordinate of the end of the ladder, or address to find X-coordinate if B1 is non-zero.
- const Short Y: Y-coordinate of the end of the ladder, or address to find Y-coordinate if B2 is non-zero.
- const Short Z: Z-coordinate of the end of the ladder, or address to find Z-coordinate if B3 is non-zero.
- const UShort I: ID of the walkmesh triangle found at the end of the ladder, or address to find ID if B4 is non-zero.
- const UByte K: The keys used to move the character on the ladder.
- const UByte A: Animation ID for the field object’s movement animation.
- const UByte D: Direction the character faces when climbing the ladder.
- const UByte S: Speed of the animation whilst climbing the ladder.
Description
Causes the character to climb a ladder; that is, switching from standard walkmesh movement, to climbing along a line connecting two points on the walkmesh.
If B1, B2, B3 or B4 is non-zero, then the value for that particular component is taken from memory using the corresponding bank and address specified, rather than as a literal value. Both retrieved values and literals can be used for different components. If using X, Y, Z or I as addresses, the lower byte should hold the address whilst the higher byte should be zero.
The coordinates specify the end-point of the ladder; the current position of the character is used as the start point. The ID of the walkmesh triangle must be specified; this is the triangle the character will step onto after reaching the end point of the ladder. The K value specifies the keys used to move the character across the ladder; keys outside the range found in the table will cause unpredictable behaviour. The animation ID specifies an offset into the field object’s animation list; this animation is played at the speed specified by S whilst the character climbs. Finally, the D argument is a direction value in the game’s standard direction format, which orients the character on the ladder.
Notes
This opcode is used as part of the character’s entity, rather than in a seperate entity, as with a LINE. A LINE is used to set the start point of the ladder on the walkmesh. When this LINE is crossed by the player, a script in the LINE then uses a PREQ, calling the script in the party leader that defines the LADER, causing the character to switch to ‘climbing mode’.
To set up a two-way ladder, two LINEs are used at either end, with different values for the LADER arguments, such as differing end points.
If this opcode is used as part of a non-playable character entity, the NPC object will automatically climb from the start to the end point without need for player interaction.
Key IDs
| ID | Key: Towards the end point | Key: Towards the start point |
|---|---|---|
| 0 | Down | Up |
| 1 | Up | Down |
| 2 | Right | Left |
| 3 | Left | Right |