first commit

assets/scripts/TrajectoryPreview.ts

@@ -0,0 +1,63 @@
+import { _decorator, Component, Node, Prefab, instantiate, Vec3 } from "cc";
+const { ccclass, property } = _decorator;
+
+@ccclass("TrajectoryPreview")
+export class TrajectoryPreview extends Component {
+  @property(Prefab)
+  pointPrefab: Prefab = null!;
+
+  @property
+  maxPoints: number = 20;
+
+  @property
+  timeStep: number = 0.1;
+
+  @property
+  gravity: Vec3 = new Vec3(0, -9.8, 0);
+
+  private points: Node[] = [];
+
+  onLoad() {
+    for (let i = 0; i < this.maxPoints; i++) {
+      const p = instantiate(this.pointPrefab);
+      p.active = false;
+      this.node.addChild(p); // 确保挂在场景下的空节点
+      this.points.push(p);
+    }
+  }
+
+  showTrajectory(
+    startPos: Vec3,
+    forward: Vec3,
+    power: number,
+    sideForce: number
+  ) {
+    const velocity = forward.multiplyScalar(power);
+    velocity.x += sideForce;
+
+    const ballRadius = 0.01; // ⚽ 球半径
+    const groundY = 0; // 🟩 地面高度
+
+    for (let i = 0; i < this.maxPoints; i++) {
+      const t = i * this.timeStep;
+
+      const pos = new Vec3(
+        startPos.x + velocity.x * t,
+        startPos.y + velocity.y * t + 0.5 * this.gravity.y * t * t,
+        startPos.z + velocity.z * t
+      );
+
+      // ⭐ 限制最低不低于地面
+      if (pos.y < groundY + ballRadius * 0.5) {
+        pos.y = groundY + ballRadius * 0.5;
+      }
+
+      this.points[i].setWorldPosition(pos);
+      this.points[i].active = true;
+    }
+  }
+
+  hideTrajectory() {
+    this.points.forEach((p) => (p.active = false));
+  }
+}