EditorWindow, do not detect a keyboard input

Input
,
1

I am working on a tool for unity and I am trying to reproduce the painting tool used in Unity Terrain.

I succed to display a circle above my mouse to show where it is going to happen thanks to those lines:

void OnSceneGUI(SceneView sceneView)
{
    Event evt = Event.current;

    if (evt.keyCode == KeyCode.LeftAlt) return;

    Ray ray = HandleUtility.GUIPointToWorldRay(evt.mousePosition);
    RaycastHit hit;

    if (Physics.Raycast(ray, out hit, Mathf.Infinity))
    {
        if (evt.IsMouseButtonDown(0))
            OnMouseButtonDown(hit);

        if (evt.IsMouseButtonDrag(0))
            OnMouseDrag(hit);

        // I am repainting the scene on every mouse movement or else, the DrawWireDisc do not follow the mouse position smoothly, I do not know if there is an other way of doing that
        Handles.DrawWireDisc(hit.point + cursorOffset.value, Vector3.up, cursorRadius.value, 2f);
        sceneView.Repaint();
    }

    if (evt.IsMouseButtonUp(0))
        OnMouseButtonUp(hit);
}

As you can see on the first lines, I added an if statement if I press the LeftAlt input to prevent the code to continue BUT it doesn’t not work and I don’t understand why.

if (evt.keyCode == KeyCode.LeftAlt) return;

I added a Debug.Log after this statement to see if the code running if I press the key and yes, it is still running.

Debug.Log(evt.keyCode == KeyCode.LeftAlt);

What is very strange is when I move my mouse, it debugs False. If I press LeftAlt it debugs True but if I do both, moving my mouse in the scene and pressing the LeftAlt, I have 2 debugs printing True and False instead of one.

Do you have any idea why it is doing that?

2

I finally find the answer to my question, to detect if an input is made on the keyboard, use:

Event.current.modifiers == EventModifiers.Alt

or for short

Event.current.alt