一.COCOSCREATOR3D 左右抛物线和垂直抛物线

• 缺点
  • 因为是根据2点之间的距离去计算时间的，所有飞行速度都是恒定的，等有空再去改改吧，或者有大佬去帮忙改一下。
  • 第一次用C3D写3D项目，还有许多写的不好的地方，请大家多多包涵。

    /** 重力加速度 */
    private _gAcc:number = -10;
    /** 抛出去的速度，值越大顶点位置越高 */
    private _shotSpeed:number = 15;
    /** 初速度向量 */
    private _speed: Vec3 = null;
    /** 重力向量 */
    private _gravity: Vec3 = null;
    /** 当前角度 */
    private _currAngle: Vec3 = null;
    private _dTime = 0;
    private _vo: WeaponVO = null;
    private _dir: number = 1;
    private _isMoving: boolean = false;
    private _damageTeam: number = -1;

    onLoad() {
        this._speed = new Vec3();
        this._gravity = new Vec3();
        this._currAngle = new Vec3();
    }

    public launchWeapon(vo: WeaponVO, damageTeam: number, startPos: Vec3, endPos: Vec3): void {
        this.startPos = startPos;
        this.endPos = endPos;
        this._vo = vo;
        this._damageTeam = damageTeam;
        this._dTime = 0;
        //设置初始位置
        this.node.setWorldPosition(this.startPos);

        //求2点之间的距离
        Vec3.subtract(_tempVec, this.startPos, this.endPos);
        const time = _tempVec.length() / this._shotSpeed;

        this._dir = this._vo.flyType === WEAPON_FLY_TYPE.LEFT_PARABOL ? -1 : 1;
        let offsetX: number, offsetY: number = 0;
        switch (this._vo.flyType) {
            case WEAPON_FLY_TYPE.LINE:
                offsetY = 0.5 * this._gAcc * time;
                break;
            default:
                offsetX = 0.5 * this._gAcc * time * this._dir;
                break;
        }

        //计算初速度
        this._speed = new Vec3((this.endPos.x - this.startPos.x) / time - offsetX, (this.endPos.y - this.startPos.y) / time - offsetY, (this.endPos.z - this.startPos.z) / time);
        //重力初速度为0
        Vec3.zero(this._gravity);
        this._isMoving = true;
    }


    update(dt: number) {
        if (!this._isMoving) return;

        if (this._vo.flyType === WEAPON_FLY_TYPE.LINE) {   //直线抛物线
            this._gravity.y = this._gAcc * (this._dTime += dt);
        } else {    //左右抛物线
            this._gravity.x = this._gAcc * (this._dTime += dt * this._dir);
        }

        //计算抛物线位置
        let pos: Vec3 = this.node.getWorldPosition();
        Vec3.add(_tempVec, this._speed, this._gravity);
        Vec3.multiplyScalar(_tempVec, _tempVec, dt);
        Vec3.add(pos, pos, _tempVec);

        if (this._vo.flyType === WEAPON_FLY_TYPE.LINE) {   //直线抛物线
            this._currAngle.x = Math.atan((this._speed.y + this._gravity.y) / this._speed.z) * MathUtil.Rad2Deg;
        } else {    //左右抛物线
            this._currAngle.y = Math.atan((this._speed.x + this._gravity.x) / this._speed.z) * MathUtil.Rad2Deg;
        }

        this.node.eulerAngles = this._currAngle;
        this.node.setWorldPosition(pos);

        //判断是否达到目标点
        Vec3.subtract(_tempVec, this.endPos, pos);
        if (_tempVec.length() <= 0.3) {
            this.arriveTarget();
        }
    }

    /**
     * 达到目标
     */
    private arriveTarget() {
        this._isMoving = false;
        PoolUtil.setNode(this.node);
        EventMgr.dispatchEvent(BattleEvent.UPDATE_BLOOD, this._damageTeam, -this._vo.damage);
        this.playBombEffect();
    }