Transform Component

The Transform component controls the translation, rotation, and scale information of an entity in the 3D world. When you create an entity in O3DE Editor, the Transform component is automatically added. The translation is the coordinate location (x, y, and z axes) of the entity. The rotation is the degree in which the entity is rotated around its center. The uniform scale is the dimension of the entity in comparison to its original size, applied uniformly in each direction.

World space refers to the entity’s absolute translation, rotation, and scale in the level. If a child is attached to a parent entity, local space refers to the entity’s translation, rotation, and scale relative to its parent entity.

Transform Component Properties

The Transform component has the following properties:

Parent entity The entity assigned as the parent. If a parent entity is specified, the Transform component follows the parent entity.

Values

The Transform component has the following values:

Translate The local position (relative to the parent) in meters.

Rotate The local rotation (relative to the parent) in degrees.

Uniform Scale The local scale, with a single value applied uniformly in each direction. Click on the Add non-uniform scale button to add a Non-uniform Scale component, which allows different scale values to be used on each axis of an entity.

Parent activation Configures transform behavior when the parent entity activates.

Static Entities that can’t be moved at run time. Some systems in O3DE treat static entities differently than movable entities (for example, the renderer can optimize static entities, making them less resource intensive to draw).

EBus Request Bus Interface

TransformBus is the request bus for the Transform component. An entity’s transform is the translation, rotation, and scale information.

For more information about using the event bus (EBus) interface, see Working with the Event Bus (EBus) system .

Use the following request functions with the EBus interface to communicate with other components of your game.

GetLocalTM

Returns the entity’s local transform. Doesn’t include the parent entity’s transform.

Parameters None

Return Entity’s local transform.

SetLocalTM

Sets the entity’s local transform, relative to its parent entity, and notifies all listeners.

Parameters Entity’s local transform.

Return None

GetWorldTM

Returns the entity’s world transform, including the parent entity’s transform.

Parameters None

Return Entity’s world transform.

SetWorldTM

Sets the world transform and notifies all listeners.

Parameters Entity’s world transform.

Return None

GetLocalAndWorld

Retrieves the entity’s local and world transforms.

Parameters Transform [out] - Local transform, relative to parent entity. Transform [out] - World transform.

Return None

SetWorldTranslation

Sets the entity’s world space translation.

Parameters New world space location, in x, y, and z coordinates. Type: Vector3

Return None

SetLocalTranslation

Sets the entity’s local space translation, which is relative to its parent entity.

Parameters New local space location, in x, y, and z coordinates. Type: Vector3

Return None

GetWorldTranslation

Gets the entity’s world space translation.

Parameters None

Return Entity’s world space, in x, y, and z coordinates. Type: Vector3

GetLocalTranslation

Gets the entity’s local space translation, which is relative to its parent entity.

Parameters None

Return Entity’s local space, in x, y, and z coordinates. Type: Vector3

MoveEntity

Moves the entity within world space.

Parameters Offset in world space, in x, y, and z coordinates. Type: Vector3

Return None

SetWorldX

Sets the entity’s translation x-axis coordinate in world space.

Parameters X-axis coordinate in world space. Type: Float

Return None

SetWorldY

Sets the entity’s translation y-axis coordinate in world space.

Parameters Y-axis coordinate in world space. Type: Float

Return None

SetWorldZ

Sets the entity’s translation z-axis coordinate in world space.

Parameters Z-axis coordinate in world space. Type: Float

Return None

GetWorldX

Gets the entity’s translation x-axis coordinate in world space.

Parameters None

Return X-axis coordinate in world space. Type: Float

GetWorldY

Gets the entity’s translation y-axis coordinate in world space.

Parameters None

Return Y-axis coordinate in world space. Type: Float

GetWorldZ

Sets the entity’s translation z-axis coordinate in world space.

Parameters None

Return Z-axis coordinate in world space. Type: Float

SetLocalX

Sets the entity’s translation x-axis coordinate in local space.

Parameters X-axis coordinate in local space. Type: Float

Return None

SetLocalY

Sets the entity’s translation y-axis coordinate in local space.

Parameters Y-axis coordinate in local space. Type: Float

Return None

SetLocalZ

Sets the entity’s translation z-axis coordinate in local space.

Parameters Z-axis coordinate in local space. Type: Float

Return None

GetLocalX

Gets the entity’s translation x-axis coordinate in local space.

Parameters None

Return X-axis coordinate in local space. Type: Float

GetLocalY

Gets the entity’s y-axis coordinate in local space.

Parameters None

Return Y-axis coordinate in local space. Type: Float

GetLocalZ

Gets the entity’s z-axis coordinate in local space.

Parameters None

Return Z-axis coordinate in local space. Type: Float

GetWorldRotation

Gets the angles in radians for each principle axis around which the world transform is rotated in the following order: z-axis, y-axis, x-axis.

Parameters None

Return The Euler angles in radians, which indicate the degree of rotation around each principle axis. Type: Vector3

GetWorldRotationQuaternion

Gets the quaternion that represents the world rotation.

Parameters None

Return The quaternion that represents the world rotation. Type: Quaternion

SetLocalRotation

Sets the local rotation around each principle axes in the following order: z-axis, y-axis, x-axis.

Parameters The Vector3 denoting radian angles of the rotations around each principle axis. Type: Vector3

Return None

SetLocalRotationQuaternion

Sets the local rotation matrix using a quaternion.

Parameters The local rotation matrix. Type: Quaternion

Return None

RotateAroundLocalX

Rotates around the local x-axis for a radian angle.

Parameters The radian angle to rotate around the local x-axis. Type: Float

Return None

RotateAroundLocalY

Rotates around the local y-axis for a radian angle.

Parameters The radian angle to rotate around the local y-axis. Type: Float

Return None

RotateAroundLocalZ

Rotates around the local z-axis for a radian angle.

Parameters The radian angle to rotate around the local z-axis. Type: Float

Return None

GetLocalRotation

Gets angles in radian for each principle axis around which the local transform is rotated in the following order: z-axis, y-axis, x-axis.

Parameters None

Return Indicates how much in radian is rotated around each principle axis. Type: Vector3

GetLocalRotationQuaternion

Gets the quaternion representing the local rotation.

Parameters None

Return The quaternion that represents the local rotation. Type: Quaternion

SetLocalUniformScale

Sets local uniform scale of the transform.

Parameters Local uniform scale of the transform, applied equally to each axis. Type: Float

Return None

GetLocalUniformScale

Gets the uniform scale value, applied equally to each axis in local space.

Parameters None

Return Uniform scale value, applied equally to each axis in local space. Type: Float

GetWorldUniformScale

Gets the uniform scale value, applied equally to each axis in world space.

Parameters None

Return Uniform scale value, applied equally to each axis in world space. Type: Float

GetParentId

Returns the parent entity’s ID. If the entity does not have a parent, the entity ID is invalid.

Parameters None

Return EntityID of the parent Type: Int

SetParent

Sets the entity’s parent entity and notifies all listeners. The entity’s local transform is moved into the parent entity’s space to preserve the entity’s world transform.

Parameters EntityId - Parent entity ID Type: Int

Return None

SetParentRelative

Sets the entity’s parent entity, moves the transform relative to the parent entity, and notifies all listeners. This function uses the world transform as a local transform and moves the transform relative to the parent entity.

Parameters EntityId - Parent entity ID Type: Int

Return None

GetChildren

Returns the entity IDs of the entity’s immediate children.

Parameters None

Return Vector of EntityIds

GetAllDescendants

Returns the entity IDs of all descendants of the entity. The descendants are the entity’s children, the children’s children, and so on. The entity IDs are ordered breadth first.

Parameters None

Return Vector of EntityIds

GetEntityAndAllDescendants

Returns the entity ID of the entity and all its descendants. The descendants are the entity’s children, the children’s children, and so on. The entity IDs are ordered breadth first, and this entity’s ID is the first in the list.

Parameters None

Return Vector of EntityIds

IsStaticTransform

Returns whether the transform is static. A static transform doesn’t move and doesn’t respond to requests to move it.

Parameters None

Return Boolean

EBus Notification Bus Interface

TransformNotificationBus is the notification bus for the Transform component. Use the following notification functions with the EBus interface to communicate with other components of your game.

For more information about using the event bus (EBus) interface, see Working with the Event Bus (EBus) system .

OnTransformChanged

Signals that the local or world transform of the entity changed.

Parameters Transform - The new local transform of the entity Transform - The new world transform of the entity

OnParentChanged

Signals that the parent of the entity changed.

Parameters EntityId - The entity ID of the previous parent. The entity ID is invalid if there was no previous parent. EntityId - The entity ID of the new parent. The entity ID is invalid if there is no new parent.

OnChildAdded

Signals that a child was added to the entity.

Parameters EntityId - The entity ID of the added child

OnChildRemoved

Signals that a child was removed from the entity.

Parameters EntityId - The entity ID of the removed child