how to exclude detection between some colliding bodies in DynamicAABBTreeCollisionManager

[Azure-Qiu]

Hi, I'm trying to apply FCL in a robotic arm, and when using fcl.DynamicAABBTreeCollisionManager I would like to exclude detection between some colliding bodies. I noticed that I can customize a callback function in manager.collide(cdata, my_callback), but I noticed that the collision objects o1,o2 in the callback function don't match the registered addresses, how do I correspond the collision objects for filtering?

import fcl
import numpy as np

def my_Callback(o1, o2, cdata):
    request = cdata.request
    result = cdata.result

    print(o1, type(o1))
    print(o2, type(o2))

    if cdata.done:
        return True

    fcl.collide(o1, o2, request, result)

    if (not request.enable_cost and result.is_collision and len(result.contacts) > request.num_max_contacts):
        cdata.done = True

    return cdata.done


# Create collision geometry and objects
geom1 = fcl.Cylinder(1.0, 1.0)
obj1 = fcl.CollisionObject(geom1)

geom2 = fcl.Cylinder(1.0, 1.0)
obj2 = fcl.CollisionObject(geom2, fcl.Transform(np.array([0.0, 0.0, 0.3])))

geom3 = fcl.Cylinder(1.0, 1.0)
obj3 = fcl.CollisionObject(geom3, fcl.Transform(np.array([0.0, 0.0, 3.0])))

geoms = [geom1, geom2, geom3]
objs = [obj1, obj2, obj3]
names = ['obj1', 'obj2', 'obj3']


# Create map from geometry IDs to objects
geom_id_to_obj = { id(geom) : obj for geom, obj in zip(geoms, objs) }

# Create map from geometry IDs to string names
geom_id_to_name = { id(geom) : name for geom, name in zip(geoms, names) }

# Create manager
manager = fcl.DynamicAABBTreeCollisionManager()
manager.registerObjects(objs)
manager.setup()

print(objs)
print(manager.getObjects())

# Create collision request structure
crequest = fcl.CollisionRequest(num_max_contacts=100, enable_contact=True)
cdata = fcl.CollisionData()

# Run collision request
manager.collide(cdata, my_Callback)

# Extract collision data from contacts and use that to infer set of
# objects that are in collision
objs_in_collision = set()

for contact in cdata.result.contacts:
    # Extract collision geometries that are in contact
    coll_geom_0 = contact.o1
    coll_geom_1 = contact.o2

    # Get their names
    coll_names = [geom_id_to_name[id(coll_geom_0)], geom_id_to_name[id(coll_geom_1)]]
    coll_names = tuple(sorted(coll_names))
    objs_in_collision.add(coll_names)

for coll_pair in objs_in_collision:
    print('Object {} in collision with object {}!'.format(coll_pair[0], coll_pair[1]))

[<fcl.fcl.CollisionObject object at 0x000002DDBFF6BE10>, <fcl.fcl.CollisionObject object at 0x000002DDD0594D20>, <fcl.fcl.CollisionObject object at 0x000002DDD0594C60>]
[<fcl.fcl.CollisionObject object at 0x000002DDBFF6BE10>, <fcl.fcl.CollisionObject object at 0x000002DDD0594D20>, <fcl.fcl.CollisionObject object at 0x000002DDD0594C60>]
<fcl.fcl.CollisionObject object at 0x000002DDD0594C00> <class 'fcl.fcl.CollisionObject'> 3151706541056
<fcl.fcl.CollisionObject object at 0x000002DDD0594CC0> <class 'fcl.fcl.CollisionObject'> 3151706541248
Object obj1 in collision with object obj2!

Thanks!