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♻️ Refactor origami map (#109)
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@bal7hazar
bal7hazar authored Oct 8, 2024
1 parent b0777e0 commit 9b881fd
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Showing 11 changed files with 347 additions and 111 deletions.
59 changes: 4 additions & 55 deletions crates/map/src/helpers/astar.cairo → crates/map/src/finders/astar.cairo
View file
Original file line number Diff line number Diff line change
Expand Up @@ -6,6 +6,7 @@ use core::dict::{Felt252Dict, Felt252DictTrait};

// Internal imports

use origami_map::finders::finder::Finder;
use origami_map::helpers::heap::{Heap, HeapTrait};
use origami_map::helpers::bitmap::Bitmap;
use origami_map::helpers::seeder::Seeder;
Expand Down Expand Up @@ -70,7 +71,7 @@ pub impl Astar of AstarTrait {
};

// [Return] The path from the start to the target
Self::path(ref heap, start, target)
Finder::path_with_heap(ref heap, start, target)
}

/// Check if the position can be visited in the specified direction.
Expand Down Expand Up @@ -123,9 +124,9 @@ pub impl Astar of AstarTrait {
fn assess(
width: u8, neighbor_position: u8, current: Node, target: Node, ref heap: Heap<Node>,
) {
let distance = Self::heuristic(current.position, neighbor_position, width);
let distance = Finder::manhattan(current.position, neighbor_position, width);
let neighbor_gcost = current.gcost + distance;
let neighbor_hcost = Self::heuristic(neighbor_position, target.position, width);
let neighbor_hcost = Finder::manhattan(neighbor_position, target.position, width);
let mut neighbor = match heap.get(neighbor_position.into()) {
Option::Some(node) => node,
Option::None => NodeTrait::new(
Expand All @@ -141,58 +142,6 @@ pub impl Astar of AstarTrait {
return heap.update(neighbor);
}
}

/// Compute the heuristic cost between two positions.
/// # Arguments
/// * `position` - The current position
/// * `target` - The target position
/// * `width` - The width of the grid
/// # Returns
/// * The heuristic cost between the two positions
#[inline]
fn heuristic(position: u8, target: u8, width: u8) -> u16 {
let (x1, y1) = (position % width, position / width);
let (x2, y2) = (target % width, target / width);
let dx = if x1 > x2 {
x1 - x2
} else {
x2 - x1
};
let dy = if y1 > y2 {
y1 - y2
} else {
y2 - y1
};
(dx + dy).into()
}

/// Reconstruct the path from the target to the start.
/// # Arguments
/// * `heap` - The heap of nodes
/// * `start` - The starting node
/// * `target` - The target node
/// # Returns
/// * The span of positions from the target to the start
#[inline]
fn path(ref heap: Heap<Node>, start: Node, target: Node) -> Span<u8> {
// [Check] The heap contains the target
let mut path: Array<u8> = array![];
match heap.get(target.position) {
Option::None => { path.span() },
Option::Some(mut current) => {
// [Compute] Reconstruct the path from the target to the start
loop {
if current.position == start.position {
break;
}
path.append(current.position);
current = heap.at(current.source);
};
// [Return] The path from the start to the target
path.span()
},
}
}
}

#[cfg(test)]
Expand Down
47 changes: 15 additions & 32 deletions crates/map/src/helpers/bfs.cairo → crates/map/src/finders/bfs.cairo
View file
Original file line number Diff line number Diff line change
Expand Up @@ -4,17 +4,17 @@
use core::dict::{Felt252Dict, Felt252DictTrait};

// Internal imports
use origami_map::helpers::astar::Astar;
use origami_map::finders::finder::Finder;
use origami_map::helpers::bitmap::Bitmap;
use origami_map::helpers::seeder::Seeder;
use origami_map::types::node::{Node, NodeTrait};
use origami_map::types::direction::{Direction, DirectionTrait};


/// BFS implementation for pathfinding
/// BreadthFirstSearch implementation for pathfinding
#[generate_trait]
pub impl BFS of BFSTrait {
/// Searches for a path from 'from' to 'to' on the given grid using BFS
pub impl BreadthFirstSearch of BreadthFirstSearchTrait {
/// Searches for a path from 'from' to 'to' on the given grid using BreadthFirstSearch
///
/// # Arguments
/// * `grid` - The grid represented as a felt252
Expand Down Expand Up @@ -42,7 +42,7 @@ pub impl BFS of BFSTrait {
let mut parents: Felt252Dict<u8> = Default::default();
visited.insert(start.position.into(), true);

// [Compute] BFS until the target is reached or queue is empty
// [Compute] BreadthFirstSearch until the target is reached or queue is empty
let mut path_found = false;
while let Option::Some(current) = queue.pop_front() {
// [Check] Stop if we reached the target
Expand All @@ -55,7 +55,7 @@ pub impl BFS of BFSTrait {
let mut directions = DirectionTrait::compute_shuffled_directions(seed);
while directions != 0 {
let direction = DirectionTrait::pop_front(ref directions);
if Astar::check(grid, width, height, current.position, direction, ref visited) {
if Finder::check(grid, width, height, current.position, direction, ref visited) {
let neighbor_position = direction.next(current.position, width);
parents.insert(neighbor_position.into(), current.position);
let neighbor = NodeTrait::new(neighbor_position, current.position, 0, 0);
Expand All @@ -69,31 +69,14 @@ pub impl BFS of BFSTrait {
if !path_found {
return array![].span();
};
Self::path(parents, start, target)
}

/// Reconstructs the path from start to target using the parents dictionary
#[inline]
fn path(mut parents: Felt252Dict<u8>, start: Node, target: Node) -> Span<u8> {
let mut path: Array<u8> = array![];
let mut current = target.position;

loop {
if current == start.position {
break;
}
path.append(current);
current = parents.get(current.into());
};

path.span()
Finder::path_with_parents(ref parents, start, target)
}
}

#[cfg(test)]
mod test {
// Local imports
use super::BFS;
use super::BreadthFirstSearch;

#[test]
fn test_bfs_search_small() {
Expand All @@ -105,7 +88,7 @@ mod test {
let height = 3;
let from = 0;
let to = 8;
let path = BFS::search(grid, width, height, from, to);
let path = BreadthFirstSearch::search(grid, width, height, from, to);
assert_eq!(path, array![8, 7, 6, 3].span());
}

Expand All @@ -119,7 +102,7 @@ mod test {
let height = 3;
let from = 0;
let to = 8;
let path = BFS::search(grid, width, height, from, to);
let path = BreadthFirstSearch::search(grid, width, height, from, to);
assert_eq!(path, array![].span());
}

Expand All @@ -134,7 +117,7 @@ mod test {
let height = 4;
let from = 0;
let to = 14;
let path = BFS::search(grid, width, height, from, to);
let path = BreadthFirstSearch::search(grid, width, height, from, to);
assert_eq!(path, array![14, 15, 11, 7, 6, 5, 4].span());
}

Expand All @@ -148,7 +131,7 @@ mod test {
let height = 2;
let from = 0;
let to = 1;
let path = BFS::search(grid, width, height, from, to);
let path = BreadthFirstSearch::search(grid, width, height, from, to);
assert_eq!(path, array![1].span());
}

Expand All @@ -164,7 +147,7 @@ mod test {
let height = 4;
let from = 0;
let to = 19;
let path = BFS::search(grid, width, height, from, to);
let path = BreadthFirstSearch::search(grid, width, height, from, to);
assert_eq!(path, array![19, 18, 13, 12, 11, 6, 1].span());
}

Expand All @@ -177,7 +160,7 @@ mod test {
let height = 1;
let from = 0;
let to = 5;
let path = BFS::search(grid, width, height, from, to);
let path = BreadthFirstSearch::search(grid, width, height, from, to);
assert_eq!(path, array![5, 4, 3, 2, 1].span());
}

Expand All @@ -192,7 +175,7 @@ mod test {
let height = 3;
let from = 0;
let to = 8;
let path = BFS::search(grid, width, height, from, to);
let path = BreadthFirstSearch::search(grid, width, height, from, to);
assert_eq!(path, array![].span());
}
}
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