Draw a 2D Path in Unity for your character to follow

There seem to be plenty of examples about how to draw a path that your character can follow in Unity 3D (emphasis on 3D), but I’m working in a 2D game, and couldn’t find what I needed. Here’s how you can draw a path in Unity 2D by using the Line Renderer. Some key points:

• I wrapped the Line Renderer in a custom class to track the actual path (hard to do with just the Line Renderer itself).
• I used prefabs although you don’t need to.
• To detect the mouse location accurately, given I had no other objects on the canvas, I needed to use a plane to cast rays and find the world coordinates.

Here is the relevant source code (full source on GitHub):

Plane plane = new Plane(Camera.main.transform.forward * -1, position);
Ray ray = Camera.main.ScreenPointToRay(Input.mousePosition);
if (plane.Raycast(ray, out float distance))
{
    if (pathGameObject == null)
    {
        // Starting a new line. Instantiate our "Path Object"
        pathGameObject =
            UnityEngine.Object.Instantiate(LinePrefab).GetComponent<PathGameObject>();
    }
    else
    {
        // TODO: Check distance between points. This just adds all of them, even
        // if you hold the mouse still.
        Vector3 hitpoint = ray.GetPoint(distance);
        pathGameObject.AddPosition(hitpoint);
    }
}

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Finally, if you’re interested in the 3D example, check out this YouTube preso.