Ghost Hit - ray_cast() returns a hit, but not on the (only) object in my drawing

Question

My Blender file has only one object, a sort of quanset hut looking mesh sitting on and above the XY plane, with its local origin at the world origin, (0,0,0). It is centered over the Y axis and extends into positive and negative Y territory.

I'm trying to use ray_cast to measure the distance of points on my mesh from the Y axis, so I have written this test to start at (0,0,0), and shoot a ray up at a 45 degree angle (1,0,1), which should intersect with my mesh.

When I ran this program, I got a hit, but it was way too close to the origin to be my mesh, which has a diameter of about 2". The hit was at (0.0182, 0.0000, 0.0182), which is the right direction all right, but way too close. When I scaled my mesh, the hit distance did not change, which meant that it was not "hitting" my mesh.

So what IS it hitting? There is no other object.

I tried moving up the Y axis to (0,1,0), no hit. Then I tried some other starting positions:

origin at (0,0,0) produced a hit at (0.0182, 0.0000, 0.0182) origin at (0,.1,0) produced a hit at (0.0171, 0.1000, 0.0171) origin at (0,.2,0) produced a hit at (0.0161, 0.2000, 0.0161) origin at (0,.21,0) produced a hit at (0.0160, 0.2100, 0.0160) origin at (0,.22,0) produced a hit at (0.0159, 0.2200, 0.0159) origin at (0,.23,0) produced no hit

Could I be hitting the 3D cursor or something? That would be weird

Here's the code:

import bpy
from mathutils import Vector

ob = bpy.data.objects['Brep.010']
origin = Vector((0,.23,0))
direction = Vector((1,0,1))
hit, loc, norm, face = ob.ray_cast(origin, direction)

if hit:
    print("Hit at ", loc, " (local)")
else:
    print("No HIT")

Answer 1

Working correctly.... No Ghosts, an Empty Proof

Object raycast is in local space. Unapplied object transforms do not effect local coordinates. The location of the object origin (aka the orange dot) is the local coordinate (0, 0, 0). The result obtained will be in blender units. If you are using imperial units there will be a conversion between native value and converted result in UI. (Much the same as native unit of rotation is radians, default display is degrees)

Scene units changed to None, showing dimensions in blender units, and empty placed at hit result.

Hit at  <Vector (0.0182, 0.0000, 0.0182)>  (local)

And again in imperial (yuck) units. 1 BU is one meter, or just over 3 feet. The result is in blender units, the UI is showing feet.

Blender Python convert units to imperial

Test script with empty parented to object at local hit location, to get a visual on result.

import bpy
from mathutils import Vector
context = bpy.context

ob = bpy.data.objects['Brep.010']
origin = Vector((0, 0, 0))
direction = Vector((1, 0, 1))
hit, loc, norm, face = ob.ray_cast(origin, direction)

if hit:
    print("Hit at ", loc, " (local)")
    bpy.ops.object.empty_add(location=loc)
    context.object.parent = ob
else:
    print("No HIT")