Callback: Animation control
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These callbacks are called, when an animation trigger happens.
| Callback | Feature | Mask property | Trigger | Variable 10 | Variable 18 |
|---|---|---|---|---|---|
| 1B | Houses | Property 14 bit 2 | Periodic, see property 16 [1] |   2.5 Random bits [2]
|
Reserved for future use |
| 1C | Houses | Property 14 bit 3 | Construction stage changes [3] | 15  Random bits
|
15 First call [4]
|
| 25 | Industry tiles | Property 11 | All triggers, see variable 18 | 2.5 Random bits [5]
|
Trigger and more, see property 11 |
| 140 | Stations, road stops | Station property 18, road stop property 10 | All triggers, see variable 18 | 2.5 Random bits [5]
|
Trigger and more, see station property 18 |
| 148 | Houses | Property 1E | Watched cargo accepted [6] | Reserved for future use | See property 1E |
| 154 | Airport tiles | Property 11 | All triggers, see variable 18 | Random bits [7] | Trigger and more, see property 11 |
| 159 | Objects | Property 13 | All triggers, see variable 18 | Random bits [7] | Trigger and more, see property 13 |
- ↑ For multi-tile houses property 19 bit 2 controls, whether the trigger is synchronised across all house tiles. See details there.
- ↑ Lower 16 bits are random per tile. Upper 16 bits are the same for all tiles, if property 19 bit 2 is set.
- ↑ During normal gameplay called 4 times per tile. During map generation called 1 time.
For the first call to happen, you also have to set property 9 bit 5.
- ↑ Var 18 bit 0 is set, if the callback is called the first time for a new house. In-game the construction stage will be zero, at map generation and in scenario editor, it will be 3.
Other bits of var 18 are reserved, and must be masked. - ↑ 5.0 5.1 Lower 16 bits are random per tile. Upper 16 bits are the same for all tiles, if the trigger applies to multiple tiles.
- ↑ Due to implementation details, up to 250 game ticks can pass between the actual acceptance and triggering this callback.
- ↑ 7.0 7.1
15 
Lower 16 bits are random per tile. Upper 16 bits are the same for all tiles, if the trigger applies to multiple tiles.
The return value has the format SSFF:
- FF: One of the following values:
Value Meaning 00 - FC Jump to this animation frame. FD leave the animation in its current state (do nothing) FE start animation with its current frame FF stop animation in its current frame
- SS: Sound effect: If non-zero, the sound effect number to play at the tile.
Note: Every time the animation frame is changed the map tile will be refreshed, even if the selected graphics stay the same. Therefore using the animation frame as a timer should be avoided, and animation triggers should be preferred instead.
