kahuna/
collapse_rule.rs

1use crate::{State, Space};
2
3/// Collapse rules define the relationships between a cell's possible state
4/// based on it's neighbors.
5/// 
6/// While this can be anything, it is recommended that collapse rules are
7/// purely subtractive in nature, either reducing or maintaining the number
8/// possible states that a cell can take on. With addative rules, runtime
9/// can be unbounded, the algorithm may (randomly) never converge on a
10/// solution.
11pub trait CollapseRule<S: State, Sp: 'static + Space<S>> {
12	/// Neighbor directions are specified as a list of coordinate deltas.
13	fn neighbor_offsets(&self) -> Box<[Sp::CoordinateDelta]>;
14	/// The collapse rule, which modifies the possible states of 'cell' based
15	/// on the states of neighboring cells.
16	/// 
17	/// * `cell` - The cell state to modify
18	/// * `neighbors` - The states of neighbors in the order specified by
19	/// `NEIGHBOR_DIRECTIONS`. `Some(<state>)` if the cell exists, and `None`
20	/// otherwise.
21	fn collapse(&self, cell: &mut S, neighbors: &[Option<S>]);
22	/// The observe rule, which forces a cell into a zero-entropy state.
23	/// 
24	/// * `cell` - The cell to observe
25	/// * `neighbors` - The states of neighbor cells as in `collapse()` above.
26	fn observe(&self, cell: &mut S, neighbors: &[Option<S>]);
27}
kahuna/collapse_rule.rs

kahuna/
collapse_rule.rs
