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primitive_object

PrimitiveObject

Bases: StatefulObject

PrimitiveObjects are objects defined by a single geom, e.g: sphere, mesh, cube, etc.

Source code in omnigibson/objects/primitive_object.py
class PrimitiveObject(StatefulObject):
    """
    PrimitiveObjects are objects defined by a single geom, e.g: sphere, mesh, cube, etc.
    """

    def __init__(
        self,
        name,
        primitive_type,
        prim_path=None,
        category="object",
        uuid=None,
        scale=None,
        visible=True,
        fixed_base=False,
        visual_only=False,
        kinematic_only=None,
        self_collisions=False,
        prim_type=PrimType.RIGID,
        load_config=None,
        abilities=None,
        include_default_states=True,
        rgba=(0.5, 0.5, 0.5, 1.0),
        radius=None,
        height=None,
        size=None,
        **kwargs,
    ):
        """
        Args:
            name (str): Name for the object. Names need to be unique per scene
            primitive_type (str): type of primitive object to create. Should be one of:
                {"Cone", "Cube", "Cylinder", "Disk", "Plane", "Sphere", "Torus"}
            prim_path (None or str): global path in the stage to this object. If not specified, will automatically be
                created at /World/<name>
            category (str): Category for the object. Defaults to "object".
            uuid (None or int): Unique unsigned-integer identifier to assign to this object (max 8-numbers).
                If None is specified, then it will be auto-generated
            scale (None or float or 3-array): if specified, sets either the uniform (float) or x,y,z (3-array) scale
                for this object. A single number corresponds to uniform scaling along the x,y,z axes, whereas a
                3-array specifies per-axis scaling.
            visible (bool): whether to render this object or not in the stage
            fixed_base (bool): whether to fix the base of this object or not
            visual_only (bool): Whether this object should be visual only (and not collide with any other objects)
            kinematic_only (None or bool): Whether this object should be kinematic only (and not get affected by any
                collisions). If None, then this value will be set to True if @fixed_base is True and some other criteria
                are satisfied (see object_base.py post_load function), else False.
            self_collisions (bool): Whether to enable self collisions for this object
            prim_type (PrimType): Which type of prim the object is, Valid options are: {PrimType.RIGID, PrimType.CLOTH}
            load_config (None or dict): If specified, should contain keyword-mapped values that are relevant for
                loading this prim at runtime.
            abilities (None or dict): If specified, manually adds specific object states to this object. It should be
                a dict in the form of {ability: {param: value}} containing object abilities and parameters to pass to
                the object state instance constructor.rgba (4-array): (R, G, B, A) values to set for this object
            include_default_states (bool): whether to include the default object states from @get_default_states
            radius (None or float): If specified, sets the radius for this object. This value is scaled by @scale
                Note: Should only be specified if the @primitive_type is one of {"Cone", "Cylinder", "Disk", "Sphere"}
            height (None or float): If specified, sets the height for this object. This value is scaled by @scale
                Note: Should only be specified if the @primitive_type is one of {"Cone", "Cylinder"}
            size (None or float): If specified, sets the size for this object. This value is scaled by @scale
                Note: Should only be specified if the @primitive_type is one of {"Cube", "Torus"}
            kwargs (dict): Additional keyword arguments that are used for other super() calls from subclasses, allowing
                for flexible compositions of various object subclasses (e.g.: Robot is USDObject + ControllableObject).
        """
        # Compose load config and add rgba values
        load_config = dict() if load_config is None else load_config
        load_config["color"] = np.array(rgba[:3])
        load_config["opacity"] = rgba[3]
        load_config["radius"] = radius
        load_config["height"] = height
        load_config["size"] = size

        # Initialize other internal variables
        self._vis_geom = None
        self._col_geom = None
        self._extents = np.ones(3)            # (x,y,z extents)

        # Make sure primitive type is valid
        assert_valid_key(key=primitive_type, valid_keys=PRIMITIVE_MESH_TYPES, name="primitive mesh type")
        self._primitive_type = primitive_type

        super().__init__(
            prim_path=prim_path,
            name=name,
            category=category,
            uuid=uuid,
            scale=scale,
            visible=visible,
            fixed_base=fixed_base,
            visual_only=visual_only,
            kinematic_only=kinematic_only,
            self_collisions=self_collisions,
            prim_type=prim_type,
            include_default_states=include_default_states,
            load_config=load_config,
            abilities=abilities,
            **kwargs,
        )

    def _load(self):
        # Define an Xform at the specified path
        prim = og.sim.stage.DefinePrim(self._prim_path, "Xform")

        # Define a nested mesh corresponding to the root link for this prim
        base_link = og.sim.stage.DefinePrim(f"{self._prim_path}/base_link", "Xform")
        self._vis_geom = create_primitive_mesh(prim_path=f"{self._prim_path}/base_link/visuals", primitive_type=self._primitive_type)
        self._col_geom = create_primitive_mesh(prim_path=f"{self._prim_path}/base_link/collisions", primitive_type=self._primitive_type)

        # Add collision API to collision geom
        lazy.pxr.UsdPhysics.CollisionAPI.Apply(self._col_geom.GetPrim())
        lazy.pxr.UsdPhysics.MeshCollisionAPI.Apply(self._col_geom.GetPrim())
        lazy.pxr.PhysxSchema.PhysxCollisionAPI.Apply(self._col_geom.GetPrim())

        # Create a material for this object for the base link
        og.sim.stage.DefinePrim(f"{self._prim_path}/Looks", "Scope")
        mat_path = f"{self._prim_path}/Looks/default"
        mat = create_pbr_material(prim_path=mat_path)
        bind_material(prim_path=self._vis_geom.GetPrim().GetPrimPath().pathString, material_path=mat_path)

        return prim

    def _post_load(self):
        # Possibly set scalings (only if the scale value is not set)
        if self._load_config["scale"] is not None:
            log.warning("Custom scale specified for primitive object, so ignoring radius, height, and size arguments!")
        else:
            if self._load_config["radius"] is not None:
                self.radius = self._load_config["radius"]
            if self._load_config["height"] is not None:
                self.height = self._load_config["height"]
            if self._load_config["size"] is not None:
                self.size = self._load_config["size"]

        # This step might will perform cloth remeshing if self._prim_type == PrimType.CLOTH.
        # Therefore, we need to apply size, radius, and height before this to scale the points properly.
        super()._post_load()

        # Cloth primitive does not have collision meshes
        if self._prim_type != PrimType.CLOTH:
            # Set the collision approximation appropriately
            if self._primitive_type == "Sphere":
                col_approximation = "boundingSphere"
            elif self._primitive_type == "Cube":
                col_approximation = "boundingCube"
            else:
                col_approximation = "convexHull"
            self.root_link.collision_meshes["collisions"].set_collision_approximation(col_approximation)

    def _initialize(self):
        # Run super first
        super()._initialize()

        # Set color and opacity
        if self._prim_type == PrimType.RIGID:
            visual_geom_prim = list(self.root_link.visual_meshes.values())[0]
        elif self._prim_type == PrimType.CLOTH:
            visual_geom_prim = self.root_link
        else:
            raise ValueError("Prim type must either be PrimType.RIGID or PrimType.CLOTH for loading a primitive object")

        visual_geom_prim.color = self._load_config["color"]
        visual_geom_prim.opacity = self._load_config["opacity"]

    @property
    def radius(self):
        """
        Gets this object's radius, if it exists.

        Note: Can only be called if the primitive type is one of {"Cone", "Cylinder", "Disk", "Sphere"}

        Returns:
            float: radius for this object
        """
        assert_valid_key(key=self._primitive_type, valid_keys=VALID_RADIUS_OBJECTS, name="primitive object with radius")
        return self._extents[0] / 2.0

    @radius.setter
    def radius(self, radius):
        """
        Sets this object's radius

        Note: Can only be called if the primitive type is one of {"Cone", "Cylinder", "Disk", "Sphere"}

        Args:
            radius (float): radius to set
        """
        assert_valid_key(key=self._primitive_type, valid_keys=VALID_RADIUS_OBJECTS, name="primitive object with radius")
        # Update the extents variable
        original_extent = np.array(self._extents)
        self._extents = np.ones(3) * radius * 2.0 if self._primitive_type == "Sphere" else \
            np.array([radius * 2.0, radius * 2.0, self._extents[2]])
        attr_pairs = []
        for geom in self._vis_geom, self._col_geom:
            if geom is not None:
                for attr in (geom.GetPointsAttr(), geom.GetNormalsAttr()):
                    vals = np.array(attr.Get()).astype(np.float64)
                    attr_pairs.append([attr, vals])
                geom.GetExtentAttr().Set(lazy.pxr.Vt.Vec3fArray([lazy.pxr.Gf.Vec3f(*(-self._extents / 2.0)), lazy.pxr.Gf.Vec3f(*(self._extents / 2.0))]))

        # Calculate how much to scale extents by and then modify the points / normals accordingly
        scaling_factor = 2.0 * radius / original_extent[0]
        for attr, vals in attr_pairs:
            # If this is a sphere, modify all 3 axes
            if self._primitive_type == "Sphere":
                vals = vals * scaling_factor
            # Otherwise, just modify the first two dimensions
            else:
                vals[:, :2] = vals[:, :2] * scaling_factor
            # Set the value
            attr.Set(lazy.pxr.Vt.Vec3fArray([lazy.pxr.Gf.Vec3f(*v) for v in vals]))

    @property
    def height(self):
        """
        Gets this object's height, if it exists.

        Note: Can only be called if the primitive type is one of {"Cone", "Cylinder"}

        Returns:
            float: height for this object
        """
        assert_valid_key(key=self._primitive_type, valid_keys=VALID_HEIGHT_OBJECTS, name="primitive object with height")
        return self._extents[2]

    @height.setter
    def height(self, height):
        """
        Sets this object's height

        Note: Can only be called if the primitive type is one of {"Cone", "Cylinder"}

        Args:
            height (float): height to set
        """
        assert_valid_key(key=self._primitive_type, valid_keys=VALID_HEIGHT_OBJECTS, name="primitive object with height")
        # Update the extents variable
        original_extent = np.array(self._extents)
        self._extents[2] = height

        # Calculate the correct scaling factor and scale the points and normals appropriately
        scaling_factor = height / original_extent[2]
        for geom in self._vis_geom, self._col_geom:
            if geom is not None:
                for attr in (geom.GetPointsAttr(), geom.GetNormalsAttr()):
                    vals = np.array(attr.Get()).astype(np.float64)
                    # Scale the z axis by the scaling factor
                    vals[:, 2] = vals[:, 2] * scaling_factor
                    attr.Set(lazy.pxr.Vt.Vec3fArray([lazy.pxr.Gf.Vec3f(*v) for v in vals]))
                geom.GetExtentAttr().Set(lazy.pxr.Vt.Vec3fArray([lazy.pxr.Gf.Vec3f(*(-self._extents / 2.0)), lazy.pxr.Gf.Vec3f(*(self._extents / 2.0))]))

    @property
    def size(self):
        """
        Gets this object's size, if it exists.

        Note: Can only be called if the primitive type is one of {"Cube", "Torus"}

        Returns:
            float: size for this object
        """
        assert_valid_key(key=self._primitive_type, valid_keys=VALID_SIZE_OBJECTS, name="primitive object with size")
        return self._extents[0]

    @size.setter
    def size(self, size):
        """
        Sets this object's size

        Note: Can only be called if the primitive type is one of {"Cube", "Torus"}

        Args:
            size (float): size to set
        """
        assert_valid_key(key=self._primitive_type, valid_keys=VALID_SIZE_OBJECTS, name="primitive object with size")

        # Update the extents variable
        original_extent = np.array(self._extents)
        self._extents = np.ones(3) * size

        # Calculate the correct scaling factor and scale the points and normals appropriately
        scaling_factor = size / original_extent[0]
        for geom in self._vis_geom, self._col_geom:
            if geom is not None:
                for attr in (geom.GetPointsAttr(), geom.GetNormalsAttr()):
                    # Scale all three axes by the scaling factor
                    vals = np.array(attr.Get()).astype(np.float64) * scaling_factor
                    attr.Set(lazy.pxr.Vt.Vec3fArray([lazy.pxr.Gf.Vec3f(*v) for v in vals]))
                geom.GetExtentAttr().Set(lazy.pxr.Vt.Vec3fArray([lazy.pxr.Gf.Vec3f(*(-self._extents / 2.0)), lazy.pxr.Gf.Vec3f(*(self._extents / 2.0))]))

    def _create_prim_with_same_kwargs(self, prim_path, name, load_config):
        # Add additional kwargs (bounding_box is already captured in load_config)
        return self.__class__(
            prim_path=prim_path,
            primitive_type=self._primitive_type,
            name=name,
            category=self.category,
            scale=self.scale,
            visible=self.visible,
            fixed_base=self.fixed_base,
            prim_type=self._prim_type,
            load_config=load_config,
            abilities=self._abilities,
            visual_only=self._visual_only,
        )

    def _dump_state(self):
        state = super()._dump_state()
        # state["extents"] = self._extents
        state["radius"] = self.radius if self._primitive_type in VALID_RADIUS_OBJECTS else -1
        state["height"] = self.height if self._primitive_type in VALID_HEIGHT_OBJECTS else -1
        state["size"] = self.size if self._primitive_type in VALID_SIZE_OBJECTS else -1
        return state

    def _load_state(self, state):
        super()._load_state(state=state)
        # self._extents = np.array(state["extents"])
        if self._primitive_type in VALID_RADIUS_OBJECTS:
            self.radius = state["radius"]
        if self._primitive_type in VALID_HEIGHT_OBJECTS:
            self.height = state["height"]
        if self._primitive_type in VALID_SIZE_OBJECTS:
            self.size = state["size"]

    def _deserialize(self, state):
        state_dict, idx = super()._deserialize(state=state)
        # state_dict["extents"] = state[idx: idx + 3]
        state_dict["radius"] = state[idx]
        state_dict["height"] = state[idx + 1]
        state_dict["size"] = state[idx + 2]
        return state_dict, idx + 3

    def _serialize(self, state):
        # Run super first
        state_flat = super()._serialize(state=state)

        return np.concatenate([
            state_flat,
            np.array([state["radius"], state["height"], state["size"]]),
        ]).astype(float)

height property writable

Gets this object's height, if it exists.

Note: Can only be called if the primitive type is one of {"Cone", "Cylinder"}

Returns:

Name Type Description
float

height for this object

radius property writable

Gets this object's radius, if it exists.

Note: Can only be called if the primitive type is one of {"Cone", "Cylinder", "Disk", "Sphere"}

Returns:

Name Type Description
float

radius for this object

size property writable

Gets this object's size, if it exists.

Note: Can only be called if the primitive type is one of {"Cube", "Torus"}

Returns:

Name Type Description
float

size for this object

__init__(name, primitive_type, prim_path=None, category='object', uuid=None, scale=None, visible=True, fixed_base=False, visual_only=False, kinematic_only=None, self_collisions=False, prim_type=PrimType.RIGID, load_config=None, abilities=None, include_default_states=True, rgba=(0.5, 0.5, 0.5, 1.0), radius=None, height=None, size=None, **kwargs)

Parameters:

Name Type Description Default
name str

Name for the object. Names need to be unique per scene

required
primitive_type str

type of primitive object to create. Should be one of:

required
prim_path None or str

global path in the stage to this object. If not specified, will automatically be created at /World/

None
category str

Category for the object. Defaults to "object".

'object'
uuid None or int

Unique unsigned-integer identifier to assign to this object (max 8-numbers). If None is specified, then it will be auto-generated

None
scale None or float or 3 - array

if specified, sets either the uniform (float) or x,y,z (3-array) scale for this object. A single number corresponds to uniform scaling along the x,y,z axes, whereas a 3-array specifies per-axis scaling.

None
visible bool

whether to render this object or not in the stage

True
fixed_base bool

whether to fix the base of this object or not

False
visual_only bool

Whether this object should be visual only (and not collide with any other objects)

False
kinematic_only None or bool

Whether this object should be kinematic only (and not get affected by any collisions). If None, then this value will be set to True if @fixed_base is True and some other criteria are satisfied (see object_base.py post_load function), else False.

None
self_collisions bool

Whether to enable self collisions for this object

False
prim_type PrimType

Which type of prim the object is, Valid options are: {PrimType.RIGID, PrimType.CLOTH}

RIGID
load_config None or dict

If specified, should contain keyword-mapped values that are relevant for loading this prim at runtime.

None
abilities None or dict

If specified, manually adds specific object states to this object. It should be a dict in the form of {ability: {param: value}} containing object abilities and parameters to pass to the object state instance constructor.rgba (4-array): (R, G, B, A) values to set for this object

None
include_default_states bool

whether to include the default object states from @get_default_states

True
radius None or float

If specified, sets the radius for this object. This value is scaled by @scale Note: Should only be specified if the @primitive_type is one of {"Cone", "Cylinder", "Disk", "Sphere"}

None
height None or float

If specified, sets the height for this object. This value is scaled by @scale Note: Should only be specified if the @primitive_type is one of {"Cone", "Cylinder"}

None
size None or float

If specified, sets the size for this object. This value is scaled by @scale Note: Should only be specified if the @primitive_type is one of {"Cube", "Torus"}

None
kwargs dict

Additional keyword arguments that are used for other super() calls from subclasses, allowing for flexible compositions of various object subclasses (e.g.: Robot is USDObject + ControllableObject).

{}
Source code in omnigibson/objects/primitive_object.py
def __init__(
    self,
    name,
    primitive_type,
    prim_path=None,
    category="object",
    uuid=None,
    scale=None,
    visible=True,
    fixed_base=False,
    visual_only=False,
    kinematic_only=None,
    self_collisions=False,
    prim_type=PrimType.RIGID,
    load_config=None,
    abilities=None,
    include_default_states=True,
    rgba=(0.5, 0.5, 0.5, 1.0),
    radius=None,
    height=None,
    size=None,
    **kwargs,
):
    """
    Args:
        name (str): Name for the object. Names need to be unique per scene
        primitive_type (str): type of primitive object to create. Should be one of:
            {"Cone", "Cube", "Cylinder", "Disk", "Plane", "Sphere", "Torus"}
        prim_path (None or str): global path in the stage to this object. If not specified, will automatically be
            created at /World/<name>
        category (str): Category for the object. Defaults to "object".
        uuid (None or int): Unique unsigned-integer identifier to assign to this object (max 8-numbers).
            If None is specified, then it will be auto-generated
        scale (None or float or 3-array): if specified, sets either the uniform (float) or x,y,z (3-array) scale
            for this object. A single number corresponds to uniform scaling along the x,y,z axes, whereas a
            3-array specifies per-axis scaling.
        visible (bool): whether to render this object or not in the stage
        fixed_base (bool): whether to fix the base of this object or not
        visual_only (bool): Whether this object should be visual only (and not collide with any other objects)
        kinematic_only (None or bool): Whether this object should be kinematic only (and not get affected by any
            collisions). If None, then this value will be set to True if @fixed_base is True and some other criteria
            are satisfied (see object_base.py post_load function), else False.
        self_collisions (bool): Whether to enable self collisions for this object
        prim_type (PrimType): Which type of prim the object is, Valid options are: {PrimType.RIGID, PrimType.CLOTH}
        load_config (None or dict): If specified, should contain keyword-mapped values that are relevant for
            loading this prim at runtime.
        abilities (None or dict): If specified, manually adds specific object states to this object. It should be
            a dict in the form of {ability: {param: value}} containing object abilities and parameters to pass to
            the object state instance constructor.rgba (4-array): (R, G, B, A) values to set for this object
        include_default_states (bool): whether to include the default object states from @get_default_states
        radius (None or float): If specified, sets the radius for this object. This value is scaled by @scale
            Note: Should only be specified if the @primitive_type is one of {"Cone", "Cylinder", "Disk", "Sphere"}
        height (None or float): If specified, sets the height for this object. This value is scaled by @scale
            Note: Should only be specified if the @primitive_type is one of {"Cone", "Cylinder"}
        size (None or float): If specified, sets the size for this object. This value is scaled by @scale
            Note: Should only be specified if the @primitive_type is one of {"Cube", "Torus"}
        kwargs (dict): Additional keyword arguments that are used for other super() calls from subclasses, allowing
            for flexible compositions of various object subclasses (e.g.: Robot is USDObject + ControllableObject).
    """
    # Compose load config and add rgba values
    load_config = dict() if load_config is None else load_config
    load_config["color"] = np.array(rgba[:3])
    load_config["opacity"] = rgba[3]
    load_config["radius"] = radius
    load_config["height"] = height
    load_config["size"] = size

    # Initialize other internal variables
    self._vis_geom = None
    self._col_geom = None
    self._extents = np.ones(3)            # (x,y,z extents)

    # Make sure primitive type is valid
    assert_valid_key(key=primitive_type, valid_keys=PRIMITIVE_MESH_TYPES, name="primitive mesh type")
    self._primitive_type = primitive_type

    super().__init__(
        prim_path=prim_path,
        name=name,
        category=category,
        uuid=uuid,
        scale=scale,
        visible=visible,
        fixed_base=fixed_base,
        visual_only=visual_only,
        kinematic_only=kinematic_only,
        self_collisions=self_collisions,
        prim_type=prim_type,
        include_default_states=include_default_states,
        load_config=load_config,
        abilities=abilities,
        **kwargs,
    )