Physics.Raycast against Mesh Collider, hits outside of the object

Unity Engine
1

I’m starting above a level and casting a ray down, then moving over a really tiny bit (.0125 meters) and doing it again, until it hits the mesh collider on the object I’m looking for. And it is finding the object, but at the first place where it first hits the object (I used a Debug.DrawRay to show where it hit) the RaycastHit.point is a bit outside of the object - not touching the object at all.

Can anyone think of a reason this would be? The collider is not marked as Convex, so should be exactly the shape of the mesh.

2

Could this be a precision issue with distances far from the center? I’m currently having this problem at a location with a Z of 1870, where the Raycast is hitting an object next to the one I’m clicking on in the editor. I’m not doing anything weird, this is my exact code:

   SceneView.onSceneGUIDelegate += PathDebugBoundariesGUI;

   ...

    static void PathDebugBoundariesGUI(SceneView sceneView)
    {
        Event cur = Event.current;
        if (cur.type == EventType.MouseDown && cur.button != 2)
        {
            RaycastHit[] allHits;
            Ray clickRay = HandleUtility.GUIPointToWorldRay(cur.mousePosition);

            allHits = Physics.RaycastAll (clickRay);

In this case I’m aiming at an object that is basically a strip of ground, the mesh is just a single layer of polygons above nothing else. But allHits is returning one object collided with, an object a little over 0.2 meters away from where the mouse clicked, even if I have the scene camera in Orthographic straight overhead.

if I add a Debug.DrawLine using clickRay, it shows the line piercing exactly where on the mesh I clicked with the mouse, and no other meshes. And the editor itself recognizes that I’m selecting that mesh and not the one next to it.

Edit: Not a precision issue with distances far from center, I moved the entire world so that the point I was trying to collide with had a Z of under 100, collision still missed. Also, without that the Raycast worked just fine further down the scene. So there’s just something wrong with the Raycast system hitting this part of this mesh.