Converts a 2D GUI position to screen pixel coordinates.
The bottom-left of the screen or window is at (0, 0). The top-right of the screen or window is at (Screen.width, Screen.height).
See Also: Input.mousePosition and Camera.ScreenPointToRay.
public static Ray GUIPointToWorldRay(Vector2 guiPos, Camera camera)
{
Vector2 screenPixelPos = HandleUtility.GUIPointToScreenPixelCoordinate(guiPos);
return camera.ScreenPointToRay(screenPixelPos);
}