Camera.ScreenToWorldPoint

Parameters

Returns

Vector3 The worldspace point created by converting the screen space point at the provided distance z from the camera plane.

Description

Transforms a point from screen space into world space, where world space is defined as the coordinate system at the very top of your game's hierarchy.

World space coordinates can still be calculated even when provided as an off-screen coordinate, for example for instantiating an off-screen object near a specific corner of the screen.

Screenspace is defined in pixels. The bottom-left of the screen is (0,0); the right-top is (pixelWidth,pixelHeight). The z position is in world units from the camera.

// Convert the 2D position of the mouse into a
// 3D position.  Display these on the game window.

using UnityEngine;

public class ExampleClass : MonoBehaviour
{
    private Camera cam;

    void Start()
    {
        cam = Camera.main;
    }

    void OnGUI()
    {
        Vector3 point = new Vector3();
        Event   currentEvent = Event.current;
        Vector2 mousePos = new Vector2();

        // Get the mouse position from Event.
        // Note that the y position from Event is inverted.
        mousePos.x = currentEvent.mousePosition.x;
        mousePos.y = cam.pixelHeight - currentEvent.mousePosition.y;

        point = cam.ScreenToWorldPoint(new Vector3(mousePos.x, mousePos.y, cam.nearClipPlane));

        GUILayout.BeginArea(new Rect(20, 20, 250, 120));
        GUILayout.Label("Screen pixels: " + cam.pixelWidth + ":" + cam.pixelHeight);
        GUILayout.Label("Mouse position: " + mousePos);
        GUILayout.Label("World position: " + point.ToString("F3"));
        GUILayout.EndArea();
    }
}