replicant.md

Replicant

from tdw.add_ons.replicant import Replicant

A Replicant is an able-bodied human-like agent that can interact with the scene with pseudo-physics behavior.

When a Replicant collides with objects, it initiates a physics-driven collision. The Replicant's own movements are driven by non-physics animation.

A Replicant can walk, turn, reach for positions or objects, grasp and drop objects, and turn its head to look around.

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Fields

• initial_position The initial position of the Replicant.

• initial_rotation The initial rotation of the Replicant.

• replicant_id The ID of this replicant.

• action The Replicant's current action. Can be None (no ongoing action).

• image_frequency An ImageFrequency value that sets how often images are captured.

• collision_detection The collision detection rules. This determines whether the Replicant will immediately stop moving or turning when it collides with something.

• static The ReplicantStatic data.

• dynamic The ReplicantDynamic data.

• commands These commands will be appended to the commands of the next communicate() call.

• initialized If True, this module has been initialized.

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Class Variables

Variable	Type	Description	Value
LIBRARY_NAME	str	The Replicants library file. You can override this to use a custom library (e.g. a local library).	"replicants.json"

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Functions

__init__

__init__

Replicant()

Replicant(replicant_id=0, position=None, rotation=None, image_frequency=ImageFrequency.once, name="replicant_0", target_framerate=100)

Parameter	Type	Default	Description
replicant_id	int	0	The ID of the Replicant.
position	POSITION	None	The position of the Replicant as an x, y, z dictionary or numpy array. If None, defaults to {"x": 0, "y": 0, "z": 0}.
rotation	ROTATION	None	The rotation of the Replicant in Euler angles (degrees) as an x, y, z dictionary or numpy array. If None, defaults to {"x": 0, "y": 0, "z": 0}.
image_frequency	ImageFrequency	ImageFrequency.once	An ImageFrequency value that sets how often images are captured.
name	str	"replicant_0"	The name of the Replicant model.
target_framerate	int	100	The target framerate. It's possible to set a higher target framerate, but doing so can lead to a loss of precision in agent movement.

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Movement

These actions move or turn the Replicant.

turn_by

self.turn_by(angle)

Turn the Replicant by an angle.

This is a non-animated action, meaning that the Replicant will immediately snap to the angle.

Parameter	Type	Default	Description
angle	float		The target angle in degrees. Positive value = clockwise turn.

turn_to

self.turn_to(target)

Turn the Replicant to face a target object or position.

This is a non-animated action, meaning that the Replicant will immediately snap to the angle.

Parameter	Type	Default	Description
target	TARGET		The target. If int: An object ID. If dict: A position as an x, y, z dictionary. If numpy array: A position as an [x, y, z] numpy array.

move_by

self.move_by(distance)

self.move_by(distance, reset_arms=True, reset_arms_duration=0.25, scale_reset_arms_duration=True, arrived_at=0.1, animation="walking_2", library="humanoid_animations.json")

Walk a given distance.

The Replicant will continuously play a walk cycle animation until the action ends.

The action can end for several reasons depending on the collision detection rules (see self.collision_detection.

• If the Replicant walks the target distance, the action succeeds.
• If collision_detection.previous_was_same == True, and the previous action was move_by() or move_to(), and it was in the same direction (forwards/backwards), and the previous action ended in failure, this action ends immediately.
• If self.collision_detection.avoid_obstacles == True and the Replicant encounters a wall or object in its path:
• If the object is in self.collision_detection.exclude_objects, the Replicant ignores it.
• Otherwise, the action ends in failure.
• If the Replicant collides with an object or a wall and self.collision_detection.objects == True and/or self.collision_detection.walls == True respectively:
• If the object is in self.collision_detection.exclude_objects, the Replicant ignores it.
• Otherwise, the action ends in failure.

Parameter	Type	Default	Description
distance	float		The target distance. If less than 0, the Replicant will walk backwards.
reset_arms	bool	True	If True, reset the arms to their neutral positions while beginning the walk cycle.
reset_arms_duration	float	0.25	The speed at which the arms are reset in seconds.
scale_reset_arms_duration	bool	True	If True, reset_arms_duration will be multiplied by framerate / 60), ensuring smoother motions at faster-than-life simulation speeds.
arrived_at	float	0.1	If at any point during the action the difference between the target distance and distance traversed is less than this, then the action is successful.
animation	str	"walking_2"	The name of the walk animation.
library	str	"humanoid_animations.json"	The name of the walk animation's library.

move_to

self.move_to(target)

self.move_to(target, reset_arms=True, reset_arms_duration=0.25, scale_reset_arms_duration=True, arrived_at=0.1, bounds_position="center", animation="walking_2", library="humanoid_animations.json")

Turn the Replicant to a target position or object and then walk to it.

While walking, the Replicant will continuously play a walk cycle animation until the action ends.

The action can end for several reasons depending on the collision detection rules (see self.collision_detection.

• If the Replicant walks the target distance, the action succeeds.
• If collision_detection.previous_was_same == True, and the previous action was move_by() or move_to(), and it was in the same direction (forwards/backwards), and the previous action ended in failure, this action ends immediately.
• If self.collision_detection.avoid_obstacles == True and the Replicant encounters a wall or object in its path:
• If the object is in self.collision_detection.exclude_objects, the Replicant ignores it.
• Otherwise, the action ends in failure.
• If the Replicant collides with an object or a wall and self.collision_detection.objects == True and/or self.collision_detection.walls == True respectively:
• If the object is in self.collision_detection.exclude_objects, the Replicant ignores it.
• Otherwise, the action ends in failure.

Parameter	Type	Default	Description
target	TARGET		The target. If int: An object ID. If dict: A position as an x, y, z dictionary. If numpy array: A position as an [x, y, z] numpy array.
reset_arms	bool	True	If True, reset the arms to their neutral positions while beginning the walk cycle.
reset_arms_duration	float	0.25	The speed at which the arms are reset in seconds.
scale_reset_arms_duration	bool	True	If True, reset_arms_duration will be multiplied by framerate / 60), ensuring smoother motions at faster-than-life simulation speeds.
arrived_at	float	0.1	If at any point during the action the difference between the target distance and distance traversed is less than this, then the action is successful.
bounds_position	str	"center"	If target is an integer object ID, move towards this bounds point of the object. Options: "center", "top", "bottom", "left", "right", "front", "back".
animation	str	"walking_2"	The name of the walk animation.
library	str	"humanoid_animations.json"	The name of the walk animation's library.

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Arm Articulation

These actions move and bend the joints of the Replicant's arms.

reach_for

self.reach_for(target, arm)

self.reach_for(target, arm, absolute=True, offhand_follows=False, arrived_at=0.09, max_distance=1.5, duration=0.25, scale_duration=True, from_held=False, held_point="bottom", plan=None)

Reach for a target object or position. One or both hands can reach for the same or separate targets.

If target is an object, the target position is a point on the object. If the object has affordance points, the target position is the affordance point closest to the hand. Otherwise, the target position is the bounds position closest to the hand.

The Replicant's arm(s) will continuously over multiple communicate() calls move until either the motion is complete or the arm collides with something (see self.collision_detection).

• If the hand is near the target at the end of the action, the action succeeds.
• If the target is too far away at the start of the action, the action fails.
• The collision detection will respond normally to walls, objects, obstacle avoidance, etc.
• If self.collision_detection.previous_was_same == True, and if the previous action was a subclass of ArmMotion, and it ended in a collision, this action ends immediately.

Parameter	Type	Default	Description
target	Union[TARGET, List[TARGET]		The target(s). This can be a list (one target per hand) or a single value (the hand's target). If int: An object ID. If dict: A position as an x, y, z dictionary. If numpy array: A position as an [x, y, z] numpy array.
arm	Union[Arm, List[Arm]		The Arm value(s) that will reach for each target as a single value or a list. Example: Arm.left or [Arm.left, Arm.right].
absolute	bool	True	If True, the target position is in world space coordinates. If False, the target position is relative to the Replicant. Ignored if target is an int.
offhand_follows	bool	False	If True, the offhand will follow the primary hand, meaning that it will maintain the same relative position. Ignored if arm is a list or target is an int.
arrived_at	float	0.09	If at the end of the action the hand(s) is this distance or less from the target position, the action succeeds.
max_distance	float	1.5	The maximum distance from the hand to the target position.
duration	float	0.25	The duration of the motion in seconds.
scale_duration	bool	True	If True, duration will be multiplied by framerate / 60), ensuring smoother motions at faster-than-life simulation speeds.
from_held	bool	False	If False, the Replicant will try to move its hand to the target. If True, the Replicant will try to move its held object to the target. This is ignored if the hand isn't holding an object.
held_point	str	"bottom"	The bounds point of the held object from which the offset will be calculated. Can be "bottom", "top", etc. For example, if this is "bottom", the Replicant will move the bottom point of its held object to the target. This is ignored if from_held == False or ths hand isn't holding an object.
plan	IkPlanType	None	An optional IkPlanType that splits this action into multiple sub-actions. If None, there is a single ReachFor action. If arm is a list, only the first element is used. offhand_follows is ignored. duration is divided by the number of sub-actions.

reset_arm

self.reset_arm(arm)

self.reset_arm(arm, duration=0.25, scale_duration=True)

Move arm(s) back to rest position(s). One or both arms can be reset at the same time.

The Replicant's arm(s) will continuously over multiple communicate() calls move until either the motion is complete or the arm collides with something (see self.collision_detection).

• The collision detection will respond normally to walls, objects, obstacle avoidance, etc.
• If self.collision_detection.previous_was_same == True, and if the previous action was an arm motion, and it ended in a collision, this action ends immediately.

Parameter	Type	Default	Description
arm	Union[Arm, List[Arm]		The Arm value(s) that will reach for the target as a single value or a list. Example: Arm.left or [Arm.left, Arm.right].
duration	float	0.25	The duration of the motion in seconds.
scale_duration	bool	True	If True, duration will be multiplied by framerate / 60), ensuring smoother motions at faster-than-life simulation speeds.

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Object Interaction

These actions involve interaction with other objects, e.g. grasping or dropping.

grasp

self.grasp(target, arm)

self.grasp(target, arm, angle=90, axis="pitch", relative_to_hand=True, offset=0)

Grasp a target object.

The action fails if the hand is already holding an object. Otherwise, the action succeeds.

When an object is grasped, it is made kinematic. Any objects contained by the object are parented to it and also made kinematic. For more information regarding containment in TDW, read this.

Parameter	Type	Default	Description
target	int		The target object ID.
arm	Arm		The Arm value for the hand that will grasp the target object.
angle	Optional[float]	90	Continuously (per communicate() call, including after this action ends), rotate the the grasped object by this many degrees relative to the hand. If None, the grasped object will maintain its initial rotation.
axis	Optional[str]	"pitch"	Continuously (per communicate() call, including after this action ends) rotate the grasped object around this axis relative to the hand. Options: "pitch", "yaw", "roll". If None, the grasped object will maintain its initial rotation.
relative_to_hand	bool	True	If True, the object rotates relative to the hand holding it. If False, the object rotates relative to the Replicant. Ignored if angle or axis is None.
offset	float	0	Offset the object's position from the Replicant's hand by this distance.

drop

self.drop(arm, offset)

self.drop(arm, max_num_frames=100, offset)

Drop a held target object.

The action ends when the object stops moving or the number of consecutive communicate() calls since dropping the object exceeds self.max_num_frames.

When an object is dropped, it is made non-kinematic. Any objects contained by the object are parented to it and also made non-kinematic. For more information regarding containment in TDW, read this.

Parameter	Type	Default	Description
arm	Arm		The Arm holding the object.
max_num_frames	int	100	Wait this number of communicate() calls maximum for the object to stop moving before ending the action.
offset	Union[float, np.ndarray, Dict[str, float]		Prior to being dropped, set the object's positional offset. This can be a float (a distance along the object's forward directional vector). Or it can be a dictionary or numpy array (a world space position).

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Head

These actions rotate the Replicant's head.

look_at

self.look_at()

self.look_at(target=target, duration=0.1, scale_duration=True)

Look at a target object or position.

The head will continuously move over multiple communicate() calls until it is looking at the target.

Parameter	Type	Default	Description
target	TARGET	target	The target. If int: An object ID. If dict: A position as an x, y, z dictionary. If numpy array: A position as an [x, y, z] numpy array.
duration	float	0.1	The duration of the motion in seconds.
scale_duration	bool	True	If True, duration will be multiplied by framerate / 60), ensuring smoother motions at faster-than-life simulation speeds.

rotate_head

self.rotate_head()

self.rotate_head(axis=axis, angle=angle, duration=0.1, scale_duration=True)

Rotate the head by an angle around an axis.

The head will continuously move over multiple communicate() calls until it is looking at the target.

Parameter	Type	Default	Description
axis	str	axis	The axis of rotation. Options: "pitch", "yaw", "roll".
angle	float	angle	The target angle in degrees.
duration	float	0.1	The duration of the motion in seconds.
scale_duration	bool	True	If True, duration will be multiplied by framerate / 60), ensuring smoother motions at faster-than-life simulation speeds.

reset_head

self.reset_head()

self.reset_head(duration=0.1, scale_duration=True)

Reset the head to its neutral rotation.

The head will continuously move over multiple communicate() calls until it is at its neutral rotation.

Parameter	Type	Default	Description
duration	float	0.1	The duration of the motion in seconds.
scale_duration	bool	True	If True, duration will be multiplied by framerate / 60), ensuring smoother motions at faster-than-life simulation speeds.

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Animation

These actions play arbitrary humanoid animations.

animate

self.animate(animation)

self.animate(animation, library="humanoid_animations.json", loop=None)

Play an animation.

The animation will end either when the animation clip is finished or if the Replicant collides with something (see self.collision_detection).

• The collision detection will respond normally to walls, objects, obstacle avoidance, etc.
• If self.collision_detection.previous_was_same == True, and it was the same animation, and it ended in a collision, this action ends immediately.

Parameter	Type	Default	Description
animation	str		The name of the animation.
library	str	"humanoid_animations.json"	The animation library.
loop	bool	None	If None, the animation will loop if this is a looping animation (see HumanoidAnimationRecord.loop); this is almost always what you want the animation to do. If True, the animation will continuously loop and the action will continue until interrupted. If False, the action ends when the animation ends.

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Misc.

Misc. non-action functions.

get_initialization_commands

self.get_initialization_commands()

This function gets called exactly once per add-on. To re-initialize, set self.initialized = False.

Returns: A list of commands that will initialize this add-on.

on_send

self.on_send(resp)

This is called within Controller.communicate(commands) after commands are sent to the build and a response is received.

Use this function to send commands to the build on the next Controller.communicate(commands) call, given the resp response. Any commands in the self.commands list will be sent on the next Controller.communicate(commands) call.

Parameter	Type	Default	Description
resp	List[bytes]		The response from the build.

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