Factories

Factories are convenience builders that create consistent worlds and their semantic annotations (views) for you. They are ideal for quickly setting up structured environments such as drawers, containers, and handles without having to wire all bodies, connections, and views manually.

Used Concepts:

• World Structure Manipulation

• Entity Query Language

• Semantic Annotations (Views)

Create a drawer with a handle

from entity_query_language import entity, an, let, symbolic_mode

from semantic_world.datastructures.prefixed_name import PrefixedName
from semantic_world.spatial_types.spatial_types import TransformationMatrix
from semantic_world.views.factories import (
    DrawerFactory,
    ContainerFactory,
    HandleFactory,
    Direction,
    SemanticPositionDescription,
    HorizontalSemanticDirection,
    VerticalSemanticDirection,
)
from semantic_world.views.views import Drawer, Handle
from semantic_world.spatial_computations.raytracer import RayTracer
from semantic_world.world_description.geometry import Scale


# Build a simple drawer with a centered handle
world = DrawerFactory(
    name=PrefixedName("drawer"),
    container_factory=ContainerFactory(name=PrefixedName("container"), direction=Direction.Z, scale=Scale(0.2, 0.4, 0.2),),
    handle_factory=HandleFactory(name=PrefixedName("handle"), scale=Scale(0.05, 0.1, 0.02)),
    semantic_position=SemanticPositionDescription(
        horizontal_direction_chain=[
            HorizontalSemanticDirection.FULLY_CENTER,
        ],
        vertical_direction_chain=[VerticalSemanticDirection.FULLY_CENTER],
    ),
).create()

print(*world.views, sep="\n")
rt = RayTracer(world)
rt.update_scene()
rt.scene.show("jupyter")

Container(name=PrefixedName(name='container', prefix=None), body=Body(name=PrefixedName(name='container', prefix=None), index=0, collision_config=CollisionCheckingConfig(buffer_zone_distance=None, violated_distance=0.0, disabled=None, max_avoided_bodies=1), temp_collision_config=None))
Handle(name=PrefixedName(name='handle', prefix=None), body=Body(name=PrefixedName(name='handle', prefix=None), index=1, collision_config=CollisionCheckingConfig(buffer_zone_distance=None, violated_distance=0.0, disabled=None, max_avoided_bodies=1), temp_collision_config=None))
Drawer(name=PrefixedName(name='drawer', prefix=None), container=Container(name=PrefixedName(name='container', prefix=None), body=Body(name=PrefixedName(name='container', prefix=None), index=0, collision_config=CollisionCheckingConfig(buffer_zone_distance=None, violated_distance=0.0, disabled=None, max_avoided_bodies=1), temp_collision_config=None)), handle=Handle(name=PrefixedName(name='handle', prefix=None), body=Body(name=PrefixedName(name='handle', prefix=None), index=1, collision_config=CollisionCheckingConfig(buffer_zone_distance=None, violated_distance=0.0, disabled=None, max_avoided_bodies=1), temp_collision_config=None)))

/opt/ros/semantic_world-venv/lib/python3.12/site-packages/probabilistic_model/distributions/uniform.py:56: RuntimeWarning: divide by zero encountered in log
  return -np.log(self.upper - self.lower)

You can query for components of the created furniture using EQL. For example, get all handles:

with symbolic_mode():
    handles = an(entity(let(Handle, world.views)))
print(*handles.evaluate(), sep="\n")

Handle(name=PrefixedName(name='handle', prefix=None), body=Body(name=PrefixedName(name='handle', prefix=None), index=1, collision_config=CollisionCheckingConfig(buffer_zone_distance=None, violated_distance=0.0, disabled=None, max_avoided_bodies=1), temp_collision_config=None))

Add another handle and filter by context

# Create an extra handle world and merge it into the existing world at a different pose
useless_handle_world = HandleFactory(name=PrefixedName("useless_handle")).create()
print(useless_handle_world.views)

with world.modify_world():
    world.merge_world_at_pose(
        useless_handle_world,
        TransformationMatrix.from_xyz_rpy(x=1.0, y=1.0),
    )

rt = RayTracer(world)
rt.update_scene()
rt.scene.show("jupyter")

[Handle(name=PrefixedName(name='useless_handle', prefix=None), body=Body(name=PrefixedName(name='useless_handle', prefix=None), index=0, collision_config=CollisionCheckingConfig(buffer_zone_distance=None, violated_distance=0.0, disabled=None, max_avoided_bodies=1), temp_collision_config=None))]

With two handles in the world, the simple handle query yields multiple results:

with symbolic_mode():
    handles = an(entity(let(Handle, world.views)))
print(*handles.evaluate(), sep="\n")

Handle(name=PrefixedName(name='handle', prefix=None), body=Body(name=PrefixedName(name='handle', prefix=None), index=1, collision_config=CollisionCheckingConfig(buffer_zone_distance=None, violated_distance=0.0, disabled=None, max_avoided_bodies=1), temp_collision_config=None))
Handle(name=PrefixedName(name='useless_handle', prefix=None), body=Body(name=PrefixedName(name='useless_handle', prefix=None), index=2, collision_config=CollisionCheckingConfig(buffer_zone_distance=None, violated_distance=0.0, disabled=None, max_avoided_bodies=1), temp_collision_config=None))

We can refine the query to get only the handle that belongs to a drawer:

with symbolic_mode():
    drawer = let(Drawer, world.views)
    handle = let(Handle, world.views)
    result = an(entity(handle, drawer.handle == handle))
print(*result.evaluate(), sep="\n")

Handle(name=PrefixedName(name='handle', prefix=None), body=Body(name=PrefixedName(name='handle', prefix=None), index=1, collision_config=CollisionCheckingConfig(buffer_zone_distance=None, violated_distance=0.0, disabled=None, max_avoided_bodies=1), temp_collision_config=None))