Building Interactive Node Graphs

In this post, I'll share some insights on building interactive node-based graph systems for the web.

Why Node Graphs?

Node graphs are powerful visual programming tools that make complex logic easier to understand and manipulate:

• Visual Clarity: See the flow of data and execution at a glance
• Modularity: Each node is a self-contained unit
• Flexibility: Easy to add new node types and behaviors

The Architecture

The system is built on several key classes:

### NodeBase
The abstract base class that all nodes inherit from. It defines the blueprint interface:

class NodeBase {
    static NodeType = "";
    static BlueprintPure_GetDefaultPins() { }
    BlueprintNativeEvent_OnRender(article, graphNode, renderCtx) { }
    async BlueprintCallable_Execute(ctx) { }
}

### Node Registry
Automatically registers node types and creates instances based on type strings.

### Execution Context
Handles the graph traversal and execution flow when nodes are triggered.

Creating Custom Nodes

To create a new node type:

1. Extend NodeBase
2. Set a unique NodeType
3. Define pins with BlueprintPure_GetDefaultPins()
4. Implement rendering in BlueprintNativeEvent_OnRender()
5. Implement logic in BlueprintCallable_Execute()

That's the blueprint system in a nutshell!