Pathfinding and walking the path

js/grid.js

@@ -5,16 +5,18 @@ export class Grid {
         this.layers = new Map();
         this.masks = new Map();
         this.prnt = prnt;
+        this.width = width;
+        this.height = height;
         this.prnt.style.display = 'grid';
-        this.prnt.style.gridTemplateColumns = `repeat(${width}, 1fr)`;
-        this.prnt.style.gridTemplateRows = `repeat(${height}, 1fr)`;
+        this.prnt.style.gridTemplateColumns = `repeat(${this.width}, 1fr)`;
+        this.prnt.style.gridTemplateRows = `repeat(${this.height}, 1fr)`;
         this.prnt.style.backgroundImage = `url("images/${tileset}/land.svg")`;
         for (let i = 0; i <= layers.length; i++) {
             const name = layers[i];
-            this.layers.set(name, new Layer(i * height, tileset));
+            this.layers.set(name, new Layer(i * this.height, tileset));
         }
         for (const name of masks) {
-            this.masks.set(name, new Mask(width, height));
+            this.masks.set(name, new Mask(this.width, this.height));
         }
     }
     add_tile(tile_factory, x, y) {
@@ -28,5 +30,54 @@ export class Grid {
         }
         return tile;
     }
+    add_debug_tile(x, y, color) {
+        const div = document.createElement('div');
+        this.prnt.appendChild(div);
+        div.style.gridColumnStart = `${x + 1}`;
+        div.style.gridRowStart = `${y + 1}`;
+        div.style.gridColumnEnd = 'span 1';
+        div.style.gridRowEnd = 'span 1';
+        div.style.backgroundColor = color;
+        div.style.opacity = '0.3';
+        div.style.zIndex = '1000000';
+    }
+    get_path(mask_name, src, dst) {
+        const mask = this.masks.get(mask_name);
+        const next = [];
+        for (let x = 0; x < this.width; x++) {
+            next.push(Array(this.height).fill(undefined));
+        }
+        // BFS
+        const queue = [dst];
+        while (queue.length) {
+            const point = queue.shift();
+            // Horizontal / vertical has to come before diagonal
+            for (const [dx, dy] of [[-1, 0], [1, 0], [0, -1], [0, 1], [-1, -1], [-1, 1], [1, -1], [1, 1]]) {
+                const check = [point[0] + dx, point[1] + dy];
+                if (next[check[0]][check[1]]) {
+                    // Already visited
+                    continue;
+                }
+                if (!mask.mask[check[0]][check[1]]) {
+                    // Not allowed
+                    continue;
+                }
+                next[check[0]][check[1]] = point;
+                if (check[0] == src[0] && check[1] == src[1]) {
+                    const path = [];
+                    let cur = src;
+                    while (cur[0] != dst[0] || cur[1] != dst[1]) {
+                        path.push(cur);
+                        cur = next[cur[0]][cur[1]];
+                    }
+                    path.push(dst);
+                    return path;
+                }
+                queue.push(check);
+            }
+        }
+        // No valid path
+        return [];
+    }
 }
 //# sourceMappingURL=grid.js.map