Ensure projectiles dont get embedded in walls or blocking tiles

src/engine/__tests__/throwing.test.ts

@@ -0,0 +1,50 @@
+import { describe, it, expect } from 'vitest';
+import { traceProjectile } from '../gameplay/CombatLogic';
+import { EntityManager } from '../EntityManager';
+import { type World, type Actor, type EntityId } from '../../core/types';
+
+const createTestWorld = (actors: Map<EntityId, Actor>): World => {
+    return {
+        width: 10,
+        height: 10,
+        tiles: new Array(100).fill(0), // 0 = Floor
+        actors,
+        exit: { x: 9, y: 9 }
+    };
+};
+
+describe('Throwing Mechanics', () => {
+    it('should land ON the wall currently (demonstrating the bug)', () => {
+        const actors = new Map<EntityId, Actor>();
+        const world = createTestWorld(actors);
+        const entityManager = new EntityManager(world);
+
+        // Wall at (5, 0)
+        world.tiles[5] = 4; // Wall
+
+        const start = { x: 0, y: 0 };
+        const target = { x: 5, y: 0 }; // Target the wall directly
+
+        const result = traceProjectile(world, start, target, entityManager);
+
+        // NEW BEHAVIOR: blockedPos is the tile BEFORE the wall (4, 0)
+        expect(result.blockedPos).toEqual({ x: 4, y: 0 });
+    });
+
+    it('should land ON the wall when throwing PAST a wall (demonstrating the bug)', () => {
+        const actors = new Map<EntityId, Actor>();
+        const world = createTestWorld(actors);
+        const entityManager = new EntityManager(world);
+
+        // Wall at (3, 0)
+        world.tiles[3] = 4; // Wall
+
+        const start = { x: 0, y: 0 };
+        const target = { x: 5, y: 0 }; // Target past the wall
+
+        const result = traceProjectile(world, start, target, entityManager);
+
+        // NEW BEHAVIOR: Hits the wall at 3,0, stops at 2,0
+        expect(result.blockedPos).toEqual({ x: 2, y: 0 });
+    });
+});

src/engine/gameplay/CombatLogic.ts

@@ -13,9 +13,9 @@ export interface ProjectileResult {
  * Calculates the path and impact of a projectile.
  */
 export function traceProjectile(
-    world: World, 
+    world: World,
-    start: Vec2, 
+    start: Vec2,
-    target: Vec2, 
+    target: Vec2,
     entityManager: EntityManager,
     shooterId?: EntityId
 ): ProjectileResult {
@@ -32,13 +32,13 @@ export function traceProjectile(
             // Check if we hit a combatant
             const actors = entityManager.getActorsAt(p.x, p.y);
             const enemy = actors.find(a => a.category === "combatant" && a.id !== shooterId);
-            
+
             if (enemy) {
                 hitActorId = enemy.id;
                 blockedPos = p;
             } else {
                 // Hit wall or other obstacle
-                blockedPos = p;
+                blockedPos = points[i - 1];
             }
             break;
         }
@@ -63,13 +63,13 @@ export function getClosestVisibleEnemy(
 ): Vec2 | null {
     let closestDistSq = Infinity;
     let closestPos: Vec2 | null = null;
-    
+
     // Helper to check visibility
     const isVisible = (x: number, y: number) => {
         if (Array.isArray(seenTiles) || seenTiles instanceof Uint8Array || seenTiles instanceof Int8Array) {
             // Flat array
             if (!width) return false;
-            return (seenTiles as any)[y * width + x]; 
+            return (seenTiles as any)[y * width + x];
         } else {
             // Set<string>
             return (seenTiles as Set<string>).has(`${x},${y}`);
@@ -78,13 +78,13 @@ export function getClosestVisibleEnemy(
 
     for (const actor of world.actors.values()) {
         if (actor.category !== "combatant" || actor.isPlayer) continue;
-        
+
         // Check visibility
         if (!isVisible(actor.pos.x, actor.pos.y)) continue;
 
         const dx = actor.pos.x - origin.x;
         const dy = actor.pos.y - origin.y;
-        const distSq = dx*dx + dy*dy;
+        const distSq = dx * dx + dy * dy;
 
         if (distSq < closestDistSq) {
             closestDistSq = distSq;