ios - 当我向左或向右移动操纵杆时，如何更改节点的纹理？

Question

我有一个由操纵杆控制的节点，当我将操纵杆向左移动时，我想更改节点的图像，当我将操纵杆向右移动时，我想更改相同的内容。我该怎么做？这是我的代码:

    override func touchesMoved(touches: Set<UITouch>, withEvent event: UIEvent?) {
    for touch in touches {
        let location = touch.locationInNode(self)

        if stickActive == true {

             //EDIT Code to change texture when moving joystick to left or right.

             if joyStick.position.x < base.position.x {

                plane.texture = SKTexture(imageNamed: "planeleft")

            } else {

                plane.texture = SKTexture(imageNamed: "planeright")

            }



        plane.removeActionForKey("stopaction")
        plane.physicsBody?.affectedByGravity = false


        xJoystickDelta = location.x - base.position.x
        yJoystickDelta = location.y - base.position.y


        let v = CGVector(dx: location.x - base.position.x, dy: location.y - base.position.x)
        let angle = atan2(v.dy, v.dx)
        let length: CGFloat = base.frame.size.height / 2
        let xDist: CGFloat = sin(angle - 1.57079633) * length
        let yDist: CGFloat = cos(angle - 1.57079633) * length


        if (CGRectContainsPoint(base.frame, location)) {
            joyStick.position = location
        }else {

            base.alpha = 0.5 //sets the opacity to 0.5 when the joystick is touched
            joyStick.position = CGPointMake(base.position.x - xDist, base.position.y + yDist)

        }
      }
    }
  }

override func update(currentTime: CFTimeInterval) {

    let xScale = 0.08 
    let yScale = 0.08

    let xAdd = self.xJoystickDelta * CGFloat(xScale)
    let yAdd = self.yJoystickDelta * CGFloat(yScale)

    self.plane.position.x += xAdd
    self.plane.position.y += yAdd
}

Answer 1

我对此不熟悉，但我知道您应该为此使用的逻辑。

复杂:

要检测操纵杆是否在左侧，您应该使用操纵杆在中间时可以到达操纵杆中心的最左边的范围。右侧将从中心到它可以到达的最右边。

简单:

对于左侧，如果摇杆小于默认中心位置，则在X值时设置。右边是比中间大的 X 位置。

这些将是更新函数内的 if 语句，因此它会不断检查这一点。在声明中将是这样的:

plane.texture = SKTexture(imageNamed: "TextureName")

注意:这一切都假设操纵杆处于固定位置并具有设定的中心

希望这对您有所帮助!