如何在Unity中将3D对象移动到屏幕的左上角？

Question

我需要将游戏对象的左上角与相机视图的左上角对齐。如何在Unity中将3D对象移动到屏幕的左上角？我无法弄清楚这一点，我找到的帖子都是在 Unity 2D 中。 谢谢您的帮助。

Answer 1

以下脚本将给定的

GameObject

移动到屏幕的左上角到相机的当前距离。如果需要的话可以改变。它根据对象相对于相机的渲染器范围来细化对象的位置：

public class SpawnScreenCorner : MonoBehaviour
{
    [Tooltip("Main cam")]
    private Camera mainCam;

    [Tooltip("Gameobject to be aligned")]
    public GameObject objToBeAligned;

    // Start is called before the first frame update
    void Start()
    {
        // Cache main camera
        mainCam = Camera.main;

        // Align obj to top left corner
        AlignObj();
    }

    // Align object to top left corner of screen
    public void AlignObj()
    {
        // Parent obj to camera temporarily
        Transform prevParent = objToBeAligned.transform.parent;
        objToBeAligned.transform.SetParent(mainCam.transform, false);

        // Get the screen's top-left corner in screen coordinates at current distance (z) of object 
        Vector3 screenTopLeft = new Vector3(0, Screen.height, objToBeAligned.transform.localPosition.z);

        // Convert the screen top-left corner to a world position
        Vector3 worldTopLeft = mainCam.ScreenToWorldPoint(screenTopLeft);

        // Adjust for the GameObject's size to align the top-left corner relative to camera space
        Vector3 adjustedPosition = worldTopLeft + mainCam.transform.InverseTransformVector(new Vector3(objToBeAligned.GetComponent<Renderer>().bounds.extents.x, -objToBeAligned.GetComponent<Renderer>().bounds.extents.y, objToBeAligned.GetComponent<Renderer>().bounds.extents.z));

        // Unparent object again
        objToBeAligned.transform.SetParent(prevParent);

        // Set the GameObject's position
        objToBeAligned.transform.position = adjustedPosition;
    }
}