计算的重复赋值

Question

我有一些不满意的 TS 代码。我正在做同样的事情三倍。这怎么可能更干净？

一个位置对象有一个 x、y 和 z 轴，可以使用 position.x = ... 设置或使用 position.set(x,y,z) 给它所有值。

我可以使用一种映射函数来遍历所有值并根据一些计算分配一个新值。

private moveTowardsCamera(camera: THREE.Camera) {
        this.children.forEach((child: Asteroid) => {
            child.position.set(
                child.position.x += (camera.position.x - child.position.x) * this.speed,
                child.position.y += (camera.position.y - child.position.y) * this.speed,
                child.position.z += (camera.position.z - child.position.z) * this.speed  
            );
            child.rotation.set(
                child.rotation.x += this.rotationIncrement,
                child.rotation.y += this.rotationIncrement,
                child.rotation.z += this.rotationIncrement
            );
        });
    }

Answer 1

您可以遍历 ['x', 'y', 'z'] 的数组，对其进行映射，并将其分散到不同的 .set 调用中：

// make sure to use `as const` here so the type doesn't get widened to Array<string>
const dims = ['x', 'y', 'z'] as const;
private moveTowardsCamera(camera: THREE.Camera) {
    this.children.forEach((child: Asteroid) => {
        child.position.set(
            ...(dims.map(dim => 
                child.position[dim] + (camera.position[dim] - child.position[dim]) * this.speed
            ) as [number, number, number])
        );
        child.rotation.set(
            ...(dims.map(dim => 
                child.rotation[dim] + this.rotationIncrement
            ) as [number, number, number])
        );
    });
}

非常确定您应该使用新的向量值调用.set 方法，而不是在调用.set 的同时重新分配child.position 或child.rotation 值。