c# - 如何将 Graphic Raycaster 与 WorldSpace UI 结合使用？

Question

我试图弄清楚 Graphic.Raycaster 是如何工作的，但文档没有帮助。我想用它从某个位置以某个角度转换光线并点击 UI。另一件事是我不知道如何让它与 UI 交互(拖动、单击等)。我知道这是一个广泛的主题，但我找不到任何关于如何使用它的好的解释，所以我将不胜感激任何解释。

Answer 1

来自 Unity 文档:

The Graphic Raycaster is used to raycast against a Canvas. The Raycaster looks at all Graphics on the canvas and determines if any of them have been hit.

您可以使用EventSystem.RaycastAll针对图形(UI)元素进行光线转换。

这是您的案例的一个简短示例:

void Update() {


// Example: get controller's current orientation:
  Quaternion ori = GvrController.Orientation;

  // If you want a vector that points in the direction of the controller
  // you can just multiply this quat by Vector3.forward:
  Vector3 vector = ori * Vector3.forward;

  // ...or you can just change the rotation of some entity on your scene
  // (e.g. the player's arm) to match the controller's orientation
  playerArmObject.transform.localRotation = ori;

  // Example: check if touchpad was just touched
  if (GvrController.TouchDown) {
    // Do something.
    // TouchDown is true for 1 frame after touchpad is touched.

    PointerEventData pointerData = new PointerEventData(EventSystem.current);

    pointerData.position = Input.mousePosition; // use the position from controller as start of raycast instead of mousePosition.

    List<RaycastResult> results = new List<RaycastResult>();
    EventSystem.current.RaycastAll(pointerData, results);

    if (results.Count > 0) {
         //WorldUI is my layer name
         if (results[0].gameObject.layer == LayerMask.NameToLayer("WorldUI")){ 
         string dbg = "Root Element: {0} \n GrandChild Element: {1}";
         Debug.Log(string.Format(dbg, results[results.Count-1].gameObject.name,results[0].gameObject.name));
         //Debug.Log("Root Element: "+results[results.Count-1].gameObject.name);
         //Debug.Log("GrandChild Element: "+results[0].gameObject.name);
          results.Clear();
     }
   }
}

以上脚本未经本人测试。所以可能会有一些错误。

以下是一些其他引用资料，可帮助您了解更多信息:

1. Graphics Raycaster of Unity; How does it work?
2. Raycast against UI in world space
3. How to raycast against uGUI objects from an arbitrary screen/canvas position
4. How do you perform a Graphic Raycast?
5. GraphicRaycaster

希望有帮助。