fix: 鸭子朝向不再读空路点

鸭子 2 只有 7 个路点，按下标计算朝向前先确认坐标存在。
Co-authored-by: Cursor <cursoragent@cursor.com>

assets/L4R1_game/scene/L4R1_game.ts

@@ -93,19 +93,40 @@ export default class SceneComponent extends MyCocosSceneComponent {
         this.duck2Moving()
 
     }
-    duck1Moving() {
-        this.duck1.position = this.duck1PosList[this._duck1Now];
+    pickNextDuckIndex(list, current) {
+        const count = list ? list.length : 0;
+        if (count <= 1) {
+            return 0;
+        }
+        let next = current;
+        for (let i = 0; i < 8 && next === current; i++) {
+            next = Math.floor(Math.random() * count);
+        }
+        return next;
+    }
 
-        cc.tween(this.duck1).to(10, { x: this.duck1PosList[this._duck1To].x, y: this.duck1PosList[this._duck1To].y }).call(() => {
+    faceDuck(duck, fromPos, toPos) {
+        if (!duck || !fromPos || !toPos) {
+            return;
+        }
+        duck.angle = 30 - 180 / Math.PI * cc.v2(toPos.x - fromPos.x, toPos.y - fromPos.y).angle(cc.v2(0, 1));
+        console.log(duck.angle);
+    }
 
-            this._duck1Now = this._duck1To;
+    duck1Moving() {
+        const nowPos = this.duck1PosList[this._duck1Now];
+        const toPos = this.duck1PosList[this._duck1To];
+        if (!nowPos || !toPos) {
+            return;
+        }
+        this.duck1.position = nowPos;
 
-            this._duck1To = Math.floor(Math.random() * 8);
+        cc.tween(this.duck1).to(10, { x: toPos.x, y: toPos.y }).call(() => {
 
+            this._duck1Now = this._duck1To;
+            this._duck1To = this.pickNextDuckIndex(this.duck1PosList, this._duck1Now);
             if (this._duck1To != this._duck1Now) {
-
-                this.duck1.angle = 30 - 180 / Math.PI * cc.v2(this.duck1PosList[this._duck1To].x - this.duck1PosList[this._duck1Now].x, this.duck1PosList[this._duck1To].y - this.duck1PosList[this._duck1Now].y).angle(cc.v2(0, 1))
-                console.log(this.duck1.angle);
+                this.faceDuck(this.duck1, this.duck1PosList[this._duck1Now], this.duck1PosList[this._duck1To]);
             }
 
             this.duck1Moving();
@@ -115,18 +136,19 @@ export default class SceneComponent extends MyCocosSceneComponent {
 
     }
     duck2Moving() {
-        this.duck2.position = this.duck2PosList[this._duck2Now];
+        const nowPos = this.duck2PosList[this._duck2Now];
+        const toPos = this.duck2PosList[this._duck2To];
+        if (!nowPos || !toPos) {
+            return;
+        }
+        this.duck2.position = nowPos;
 
-        cc.tween(this.duck2).to(10, { x: this.duck2PosList[this._duck2To].x, y: this.duck2PosList[this._duck2To].y }).call(() => {
+        cc.tween(this.duck2).to(10, { x: toPos.x, y: toPos.y }).call(() => {
 
             this._duck2Now = this._duck2To;
-
-            this._duck2To = Math.floor(Math.random() * 8);
-
+            this._duck2To = this.pickNextDuckIndex(this.duck2PosList, this._duck2Now);
             if (this._duck2To != this._duck2Now) {
-
-                this.duck2.angle = 30 - 180 / Math.PI * cc.v2(this.duck2PosList[this._duck2To].x - this.duck2PosList[this._duck2Now].x, this.duck2PosList[this._duck2To].y - this.duck2PosList[this._duck2Now].y).angle(cc.v2(0, 1))
-                console.log(this.duck2.angle);
+                this.faceDuck(this.duck2, this.duck2PosList[this._duck2Now], this.duck2PosList[this._duck2To]);
             }
 
             this.duck2Moving();