Node

Base class for all scene graph objects.

Node represents a transformable object that can be placed within a scene graph hierarchy. Nodes support local and world transforms, parent-child relationships, and can respond to events and updates. All renderable, light-emitting, and camera entities in the engine inherit from this class.

Nodes can be organized in a tree structure, and transformations will propagate through the hierarchy. When attached to a scene, nodes gain access to the shared context and may perform initialization in OnAttached.

To define behavior, override virtual methods such as OnUpdate, OnKeyboardEvent, or OnMouseEvent.

Construction

Constructors

Node()

Constructs an Node instance.

Node::Node();

Factories preferred

Node::Create() auto

Creates a shared pointer to a Node object.

static auto Node::Create();

Types

Node::Type enum

Enumerates all node types.

Each node subclass identifies its type through Node::GetNodeType, allowing runtime checks and scene traversal logic to distinguish between different kinds of nodes. The engine uses these identifiers internally for tasks such as culling, rendering, and event dispatch.

Value	Description
Camera	Perspective or orthographic camera.
Default	Generic node without special behavior.
InstancedMesh	Node containing instanced geometry.
Light	Light source (directional, point, or spot).
Mesh	Single mesh with an associated material.
Renderable	Any node that can be rendered to the screen.
Scene	Root of a scene hierarchy.
Sprite	Billboarded sprite.

Properties

frustum_culled bool

If true, the node is subject to frustum culling during rendering.

bool frustum_culled {true};

transform Transform3

Local transformation.

Transform3 transform {};

transform_auto_update bool

If true, the local transform is automatically updated before rendering.

bool transform_auto_update {true};

up Vector3

Local up direction (defaults to +Y).

Vector3 up {Vector3::Up()};

Functions

LookAt() void virtual

Rotates the node to face a given target position in world space.

virtual void Node::LookAt(const Vector3& target);

Parameter	Description
target	Target world-space position to look at.

TranslateX() auto

Translates the node along the X axis in local space.

auto Node::TranslateX(float value);

Parameter	Description
value	Translation distance.

TranslateY() auto

Translates the node along the Y axis in local space.

auto Node::TranslateY(float value);

Parameter	Description
value	Translation distance.

TranslateZ() auto

Translates the node along the Z axis in local space.

auto Node::TranslateZ(float value);

Parameter	Description
value	Translation distance.

RotateX() auto

Rotates the node along the X axis in local space.

auto Node::RotateX(float angle);

Parameter	Description
angle	Rotation angle in radians.

RotateY() auto

Rotates the node along the Y axis in local space.

auto Node::RotateY(float angle);

Parameter	Description
angle	Rotation angle in radians.

RotateZ() auto

Rotates the node along the Z axis in local space.

auto Node::RotateZ(float angle);

Parameter	Description
angle	Rotation angle in radians.

SetScale() auto

Scales the node non-uniformly in local space.

auto Node::SetScale(const Vector3& value);

Parameter	Description
value	Scale vector applied to the X, Y, and Z axes.

OnUpdate() void virtual

Called every frame.

Override this method to implement per-frame logic or animation.

virtual void Node::OnUpdate(float delta);

Parameter	Description
delta	Time in seconds since the last frame.

OnAttached() void virtual

Called when the node becomes part of an attached scene.

This method is invoked when the node is added to a scene that is currently attached to the application context. The shared context is guaranteed to be initialized and available. Use this hook to perform resource loading or event registration that depends on application state.

virtual void Node::OnAttached(SharedContextPointer context);

Parameter	Description
context	Pointer to the shared context.

OnKeyboardEvent() void virtual

Called when a keyboard event is dispatched to this node.

Override to handle key presses or releases.

virtual void Node::OnKeyboardEvent(KeyboardEvent* event);

Parameter	Description
event	Pointer to the dispatched keyboard event.

OnMouseEvent() void virtual

Called when a mouse event is dispatched to this node.

Override to handle mouse movement, clicks, or scrolling.

virtual void Node::OnMouseEvent(MouseEvent* event);

Parameter	Description
event	Pointer to the dispatched mouse event.

Add() void

Adds a child node to this node.

void Node::Add(const std::shared_ptr<Node> & node);

Parameter	Description
node	Child node to add.

Children() const std::vector<std::shared_ptr<Node> > &

Returns the list of child nodes.

const std::vector<std::shared_ptr< Node> > & Node::Children() const;

GetNodeType() Node::Type virtual

Returns node type.

virtual Type vglx::Node::GetNodeType() const;

GetWorldPosition() Vector3

Returns the world-space position of this node.

Vector3 Node::GetWorldPosition();

GetWorldTransform() Matrix4

Returns the world transformation matrix of this node.

Matrix4 Node::GetWorldTransform();

IsChild() bool

Checks whether the given node is a direct child of this node.

bool Node::IsChild(const Node* node) const;

Parameter	Description
node	Pointer to the node to check.

IsRenderable() bool virtual

Returns true if the node is renderable.

virtual bool Node::IsRenderable() const;

Parent() constNode*

Returns the parent node.

const Node* Node::Parent() const;

Remove() void

Removes a child node from this node.

void Node::Remove(const std::shared_ptr<Node> & node);

Parameter	Description
node	Child node to remove.

RemoveAllChildren() void

Removes all children from this node.

void Node::RemoveAllChildren();

ShouldUpdateWorldTransform() bool

Determines whether the world transform should be recalculated.

bool Node::ShouldUpdateWorldTransform() const;

UpdateTransformHierarchy() void

Recursively updates this node and all child world transforms.

This updates the transformation matrix of the current node first, then propagates the update recursively through all children.

void Node::UpdateTransformHierarchy();

UpdateWorldTransform() void

Updates this node’s world transform, ensuring parent transforms are current.

This ensures that the world transform of all ancestors is updated before updating the current node. Required for correct world positioning.

void Node::UpdateWorldTransform();