Vfrdtyky

Generally, most objects are placed in the scene view by dragging or something. I want to right click the mouse (without dragging an object) to create an object in the scene view. I know this would require some editor coding but I’m not sure how to go about it.

UPDATE

After giving it some thought I realised that using a MenuItem would be quite appropriate for me. Here is my code below:

SLMenuItems:

public class SLMenuItems : MonoBehaviour {



public bool canClickSceneViewToCreatePath = false;



void Start()

{



}



[MenuItem("Component/Create Custom Object")]

static void CreateObject()  {

   Debug.Log("menu item selected");

    canClickSceneViewToCreatePath = true;

} 

}

SLMenuItemsEditor:

    [CustomEditor(typeof(SLMenuItems))]

public class SLMenuItemsEditor : Editor {

    SLMenuItems slMenuItems;





    void OnEnable()

    {

        slMenuItems = (SLMenuItems)target;



    }





    void OnSceneGUI()

        {

            if (slMenuItems.canClickSceneViewToCreatePath)  {

                Vector3 pointsPos = HandleUtility.GUIPointToWorldRay(Event.current.mousePosition).origin;



                if (Event.current.type == EventType.MouseDown && Event.current.button == 0)

                {



                    // create object here at pointsPos



                    slMenuItems.canClickSceneViewToCreatePath = false;

                }

            }



        }

    }

I keep getting the following error:

Assets/SLMenuItems.cs(23,9): error CS0120: An object reference is required to access non-static member `SLMenuItems.canClickSceneViewToCreatePath'

pointing to the line:

canClickSceneViewToCreatePath = true;

in SLMenuItems.

Your CreateObject method is static but your canClickSceneViewToCreatePath value is not.

It has nothing to do with the editor script but with your class SlMenuItems itself.

A static method is not instanced or with other words it is kind of shared between all instances of that component type while the non-static value might be different for each component.

So how should a static method - which is the same for all instances - "know", which of the instances values it should access?

So either make the method non-static or the variable static. Depending on what your further need is.

Since the MenuItem needs a static method make the variable static as well.

I would suggest you make that class not inherit from MonoBehaviour at all since it doesn't have any behaviour for a GameObject. It only brings some editor features so rather make it a static class that can "live" in the Assets without needing to be instanced.

Than you can use SceneView.onSceneGUIDelegate to register a callback for OnSceneGUI without implementing an editor script for that:

private static GameObject lastCreated;



private static bool isCreating;



public static class SLMenuItems

{   

    [MenuItem("Component/Create Custom Object")]

    private static void CreateObject() 

    {

        Debug.Log("menu item selected");



        isCreating = true;

        lastCreated = null;



        // Add a callback for SceneView update

        SceneView.onSceneGUIDelegate -= UpdateSceneView;

        SceneView.onSceneGUIDelegate += UpdateSceneView;

    }



    private static void UpdateSceneView(SceneView sceneView)

    {

        if(lastCreated)

        {

            // Keep lastCreated focused

            Selection.activeGameObject = lastCreated;

        }



        if(isCreating)

        {  

            if (Event.current.type == EventType.MouseDown && Event.current.button == 0)

            {

                Vector3 pointsPos = HandleUtility.GUIPointToWorldRay(Event.current.mousePosition).origin;



                //Todo create object here at pointsPos

                lastCreated = Instantiate(somePrefab);



                // Avoid the current event being propagated

                // I'm not sure which of both works better here

                Event.current.Use();

                Event.current = null;



                // Keep the created object in focus

                Selection.activeGameObject = lastCreated;



                // exit creation mode

                isCreating = false;

            }

        } 

        else

        {

            // Skip if event is Layout or Repaint

            if(e.type == EventType.Layout || e.type == EventType.Repaint)

            {

                Selection.activeGameObject = lastCreated;

                return;

            }



            // Prevent Propagation

            Event.current.Use();

            Event.current = null;

            Selection.activeGameObject = lastCreated;

            lastCreated = null;



            // Remove the callback

            SceneView.onSceneGUIDelegate -= UpdateSceneView;

        }      

    }

}

But I suggest you change your questions title since this is actually not the solution to the "task" you describe before.