Graph Definition

Graph is the root API for a graph type. It owns a CustomGraphModelImpl and defines what the graph supports.

public abstract class Graph implements IGraph {
    public final CustomGraphModelImpl graphModel = createGraphModel();

    public abstract List<Class<? extends Node>> getSupportNodes();
}

Node Registry

Use GraphNodeRegistry when your nodes are declared with @NodeAttribute.

public class MyGraph extends Graph {
    public static final GraphNodeRegistry NODE_REGISTRY =
            GraphNodeRegistry.create(MyMod.id("my_graph"), MyGraph.class);

    @Override
    public List<Class<? extends Node>> getSupportNodes() {
        return NODE_REGISTRY.getNodeClasses();
    }
}

GraphNodeRegistry filters annotated nodes by graph type, mod id, and registration environment.

Node Attribute

@NodeAttribute(
        name = "add",
        group = "math",
        graphTypes = {MyGraph.class}
)
public class AddNode extends Node {
}

Field	Description
name	Node id used by the graph toolkit.
group	Item library grouping path.
modID	Optional mod filter.
priority	Sort priority.
environment	Registration environment.
graphTypes	Graph classes this node can be used in.

Supported Types

getSupportTypes() controls type handles available to ports, constants, and variables. See Type Handles for the type API and registration helpers.

@Override
public @Nullable List<TypeHandle> getSupportTypes() {
    return List.of(TypeHandles.FLOAT, TypeHandles.STRING, TypeHandles.BOOL);
}

Return null to let CustomGraphModelImpl.detectSupportedTypes(graphModel) collect port types from supported nodes.

You can also tune UI lists separately:

@Override
public List<TypeHandle> getLibrarySupportTypes() {
    return List.of(TypeHandles.FLOAT);
}

@Override
public List<TypeHandle> getVariableSupportTypes() {
    return List.of(TypeHandles.FLOAT, TypeHandles.BOOL);
}

By default, getVariableSupportTypes() returns getSupportTypes(), and getLibrarySupportTypes() returns null. A null library list keeps only the supported types a literal can be authored of: those for which TypeHandleHelpers.canAuthorLiteral(handle) is true, meaning the handle has a registered default value.

WARNING

Since 2.2.41, the item library no longer offers a constant node for every supported type. Before 2.2.41, the default was the whole getSupportTypes() list.

Types without a default value are now left out. This includes custom types registered without setCustomDefaultValue(...), plain enums, and the built-in TypeHandles.DIRECTION. To bring one back, register a default value:

TypeHandleHelpers.setCustomDefaultValue(TypeHandles.DIRECTION, () -> Direction.NORTH);

Or override getLibrarySupportTypes() and list the types yourself.

Graph Hooks

Use graph hooks when behavior belongs to the graph type instead of one GraphView instance.

@Override
public boolean canExecuteCommand(IGraphCommand command) {
    return true;
}

@Override
public void onCommandExecuted(IGraphCommand command) {
}

@Override
public void onGraphChanged(GraphLogger logger) {
    logger.warning(Component.literal("Missing output"));
}

canExecuteCommand can veto editor changes.

onCommandExecuted runs after a command has changed the graph.

onGraphChanged emits footer diagnostics in the graph view. Messages are runtime UI state and are not serialized.

Subgraph Support

Same-type local subgraphs are supported by default. Cross-type subgraphs require opt-in:

@Override
public boolean acceptsSubgraphGraph(Graph other) {
    return other instanceof MaterialGraph;
}

Use getSupportedSubgraphVariableKinds() to control which exposed variable kinds become ports when this graph is used as a subgraph.