NodeSystemInterface Manual

Table of Contents

• About
• Access
• Use

About

maxon::nodes::NodeSystemInterface is a node system. This is the fundamental data structure which is being edited by a user through the maxon::GraphModelInterface from the graph.framework. A node system stores a hierarchy of objects (nodes and ports) and connections.

Note

Node systems support COW behaviour.

To traverse a node system, the classes maxon::nodes::Node, maxon::nodes::PortList and maxon::nodes::Port exist. See Nodes Manual.

Access

The node system is obtained with:

• maxon::nodes::NodesGraphModelInterface::GetNodeSystem(): Returns the node system.
• maxon::nodes::NodesGraphModelInterface::GetMutableNodeSystem(): Returns the mutable node system.

See NodesGraphModelInterface Manual and NodeMaterial Manual.

  // This example obtains the NodeSystem from the given NodeMaterial.
 
  const maxon::nodes::NodesGraphModelRef& graph  = nodeMaterial->GetGraph(nodeSpaceID) iferr_return;
  const maxon::nodes::NodeSystem&         system = graph.GetNodeSystem();

Use

The node system gives access to its nodes via the root node:

• maxon::nodes::NodeSystemInterface::GetRoot(): Returns the root maxon::nodes::Node.

See Nodes Manual.

  // This example accesses the node systems root node and loops over all its children.
 
  // get root node
  maxon::nodes::Node node = system.GetRoot();
 
  // check children
  for (auto c : node.GetChildren())
  {
    maxon::nodes::Node child = c iferr_return;
    DiagnosticOutput("Child: @", child);
  }

A modification to a node system is handled with:

• maxon::nodes::NodeSystemInterface::BeginModification(): Indicates the beginning of a sequence of modifications and returns the root node of this node system as a MutableRoot.
• maxon::nodes::NodeSystemInterface::BeginInstantiationModification():
• maxon::nodes::NodeSystemInterface::BeginSubstitutionModification():
• maxon::nodes::NodeSystemInterface::IsFinalized(): Returns true if this node system is in finalized state. A node system is in finalized state after maxon::nodes::MutableRoot::EndModification() has been called

Note

Typically a node system is edited as a graph model, see GraphModelInterface Manual.

Modifications are obtained with:

• maxon::nodes::NodeSystemInterface::GetModificationStamp(): Returns the maxon::TimeStamp.
• maxon::nodes::NodeSystemInterface::GetModificationsSince(): Reports all modifications which have been made since the given stamp.

The values of node attributes are edited with:

• maxon::nodes::NodeSystemInterface::SetValue(): Sets the value of the given attribute.

The node system can be serialized with:

• maxon::nodes::NodeSystemInterface::GetNodeSystemData(): Returns the maxon::nodes::NodeSystemData (see maxon::nodes::NodeSystemDataInterface).
• maxon::nodes::NodeSystemInterface::WriteGml(): Writes the node system to a GML file. See maxon::nodes::NodeSystemInterface::GML_OPTIONS.

Node Template:

• maxon::nodes::NodeSystemInterface::GetTemplate(): Returns the node template which instantiated this node system.
• maxon::nodes::NodeSystemInterface::GetArguments(): Returns the template arguments which have been used for this instantiation of a node template.

Further functions are:

• maxon::nodes::NodeSystemInterface::GetNodeSystemClass(): Returns the node system class, see NodeSystemClassInterface Implementation.
• maxon::nodes::NodeSystemInterface::GetDerivationHandler(): Returns the derivation handler of this node system.
• maxon::nodes::NodeSystemInterface::GetBase(): Returns the base node system of which this node system is an instance.
• maxon::nodes::NodeSystemInterface::CreateInstance(): Creates an instance of this node system.
• maxon::nodes::NodeSystemInterface::CreateCopyOfSelection(): Returns a new node system which is a copy of the given subgraph.
• maxon::nodes::NodeSystemInterface::GetTopologicalOrder(): Returns a maxon::Int value which corresponds to the index of the given port in the topological ordering.
• maxon::nodes::NodeSystemInterface::GetTopLevelPorts(): Yields all top-level ports to the receiver in topological order.