differences in AABB in pybullet/blender/trimesh

[shivanimall]

Hello @erwincoumans ,

I loaded an obj mesh A into pybullet, trimesh and bpy(blender) and I received different values for the AABB.
Default blender units are meters.

But how should I interpret these values and convert from one to another (since these don't seem to match)?
Please let me know if I am missing something, thank you!

Here is a way to reproduce this:

>>> a = pb.loadURDF("/Library/Frameworks/Python.framework/Versions/3.9/lib/python3.9/site-packages/pybullet_data/random_urdfs/898/898.urdf")
>>> pb.getBasePositionAndOrientation(a)
((0.0, 0.0, 0.0), (0.0, 0.0, 0.0, 1.0))
>>> import trimesh
>>> b  = trimesh.load("/Library/Frameworks/Python.framework/Versions/3.9/lib/python3.9/site-packages/pybullet_data/random_urdfs/898/898.obj")
>>> b.convex_hull.center_mass
array([-0.00265061, -0.07180371, -0.01703506])
>>> b.bounds
array([[-1.02987575, -4.78705957, -1.09513578],
       [ 1.05835325,  3.41675443,  1.08260422]])
>>> pb.getAABB(a)
((-0.018494009256362916, -0.07152644920349122, -0.019676430702209476), (0.018829424858093267, 0.05753076124191284, 0.018989670753479005))
>>> import bpy
>>> obj_object = bpy.context.selected_objects[0]
>>> obj_object1 = bpy.context.selected_objects[1]
>>> bpy.data.objects['convex_1'].dimensions
Vector((2.088228940963745, 6.205067157745361, 2.1777400970458984))
>>> bpy.data.objects['convex_0'].dimensions
Vector((1.1336179971694946, 1.9987468719482422, 1.0739539861679077))