feat: Transform origin and direction to account for level transformat…

…ion (#404)

examples/levelraycast.js

@@ -0,0 +1,45 @@
+kaplay({
+    background: [31, 16, 42],
+});
+
+loadSprite("grass", "/sprites/grass.png");
+
+const level = addLevel([
+    "===",
+    "= =",
+    "===",
+], {
+    tileWidth: 64,
+    tileHeight: 64,
+    pos: vec2(256, 128),
+    tiles: {
+        "=": () => [
+            sprite("grass"),
+            area(),
+        ],
+    },
+});
+level.use(rotate(45))
+
+onLoad(() => {
+    level.spawn([
+        pos(
+            level.tileWidth() * 1.5,
+            level.tileHeight() * 1.5
+        ),
+        circle(6),
+        color('#ea6262'),
+        {
+            add() {
+                const rayHit = level.raycast(
+                    this.pos,
+                    Vec2.fromAngle(0).scale(100)
+                );
+
+                debug.log(`${rayHit != null} ${rayHit && rayHit.object ? rayHit.object.id : -1}`);
+            },
+        },
+    ])
+})
+
+debug.inspect = true

src/game/level.ts

@@ -7,6 +7,7 @@ import {
     vec2,
     type Vec2Args,
 } from "../math/math";
+import { calcTransform } from "../math/various";
 import type { CompList, GameObj, LevelComp, PathFindOpt } from "../types";
 import { BinaryHeap } from "../utils";
 
@@ -351,6 +352,8 @@ export function addLevel(
             }
 
             obj.tilePos = p;
+            // Stale, so recalculate
+            obj.transform = calcTransform(obj);
 
             if (spatialMap) {
                 insertIntoSpatialMap(obj);
@@ -412,7 +415,9 @@ export function addLevel(
             return spatialMap![hash] || [];
         },
 
-        raycast(origin: Vec2, direction: Vec2) {
+        raycast(this: GameObj<LevelComp | PosComp>, origin: Vec2, direction: Vec2) {
+            const worldOrigin = this.toWorld(origin);
+            const worldDirection = this.toWorld(origin.add(direction)).sub(worldOrigin);
             const levelOrigin = origin.scale(
                 1 / this.tileWidth(),
                 1 / this.tileHeight(),
@@ -427,8 +432,8 @@ export function addLevel(
                     if (tile.is("area")) {
                         const shape = tile.worldArea();
                         const hit = shape.raycast(
-                            origin,
-                            direction,
+                            worldOrigin,
+                            worldDirection,
                         ) as RaycastResult;
                         if (hit) {
                             if (minHit) {