Transforms and Hierarchies

Every GameObject owns a Transform with 2D position, rotation, scale, and optional parenting. Local values are relative to the parent; world values include the full hierarchy.

Local and world properties

transform.LocalPosition = new Vector2(40, 20);
transform.LocalRotation = MathF.PI / 2f;
transform.LocalScale = new Vector2(2, 2);

Vector2 worldPosition = transform.Position;
float worldRotation = transform.Rotation;
Vector2 approximateWorldScale = transform.LossyScale;
Matrix3x2 worldMatrix = transform.WorldMatrix;

Rotation values are radians. LocalMatrix applies scale, then rotation, then translation. WorldMatrix composes the local matrix with every parent.

LossyScale is the component-wise accumulated scale. It is convenient for ordinary 2D hierarchies but does not represent skew that can arise from mixed non-uniform scales and rotations.

Translate and rotate

transform.Translate(new Vector2(10, 0));
transform.Rotate(MathF.PI / 8f);

The default Translate amount is interpreted in the parent's coordinate space. Pass localSpace: true to move along the transform's current right and up directions:

transform.Translate(new Vector2(speed * deltaTime, 0), localSpace: true);

Right points along the transform's local positive X direction. Up follows the screen-oriented 2D convention and points along local negative Y at zero rotation.

Look at a target

transform.LookAt(target.Transform.Position);

LookAt rotates local positive X toward a world-space target and compensates for parent rotation.

Parent objects

weapon.Transform.SetParent(player.Transform);

Parenting preserves the child's current world position, rotation, and scale by default. Pass worldPositionStays: false to retain its local values instead:

weapon.Transform.SetParent(player.Transform, worldPositionStays: false);
weapon.Transform.LocalPosition = new Vector2(12, 4);

Assigning the Parent property is equivalent to SetParent(newParent) with world preservation. Cycles are rejected. Children provides a read-only view of direct child transforms.

Destroying a GameObject detaches its transform. Its children keep their world transforms and become root transforms; they are not destroyed automatically.

Convert points

Vector2 muzzleInWorld = weapon.Transform.TransformPoint(new Vector2(16, 0));
Vector2 pointInWeaponSpace = weapon.Transform.InverseTransformPoint(worldPoint);

InverseTransformPoint throws if the world matrix cannot be inverted, such as when a transform has zero scale.