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    Litegraph.js

    A graph node engine and editor written in Javascript similar to PD or UDK Blueprints, comes with its own editor in HTML5 Canvas2D. The engine can run client side or server side using Node. It allows to export graphs as JSONs to be included in applications independently.
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    litegraph.js

    A library in Javascript to create graphs in the browser similar to Unreal Blueprints. Nodes can be programmed easily and it includes an editor to construct the graphs.

    It can be integrated easily in any existing web applications and graphs can be run without the need of the editor.

    Try it in the demo site.

    Node Graph

    Features

    • Renders on Canvas2D (zoom in, zoom out, panning, can be used inside a WebGLTexture)
    • Easy to use editor (searchbox, keyboard shortcuts, multiple selection, context menu, ...)
    • Optimized to support hundreds of nodes per graph (on editor but also on execution)
    • Customizable theme (colors, shapes, background)
    • Callbacks to personalize every action/drawing/event of nodes
    • Subgraphs (nodes that contain graphs themselves)
    • Live mode system (hides the graph but calls nodes to render whatever they want, useful to create UIs)
    • Graphs can be executed in NodeJS
    • Highly customizable nodes (color, shape, slots vertical or horizontal, widgets, custom rendering)
    • Easy to integrate in any JS application

    Nodes provided

    Although it is easy to create new node types, LiteGraph comes with some default nodes that could be useful for many cases:

    • Interface (Widgets)
    • Math (trigonometry, math operations)
    • Audio (AudioAPI and MIDI)
    • 3D Graphics (Postprocessing in WebGL)
    • Input (read Gamepad)

    Installation

    You can install it using npm

    npm install litegraph.js
    

    Or downloading the build/litegraph.js version from this repository.

    First project

    <html>
    <head>
        <link rel="stylesheet" type="text/css" href="litegraph.css">
        <script type="text/javascript" src="litegraph.js"></script>
    </head>
    <body style='width:100%; height:100%'>
    <canvas id='mycanvas' width='1024' height='720' style='border: 1px solid'></canvas>
    <script>
    var graph = new LGraph();
    
    var canvas = new LGraphCanvas("#mycanvas", graph);
    
    var node_const = LiteGraph.createNode("basic/const");
    node_const.pos = [200,200];
    graph.add(node_const);
    node_const.setValue(4.5);
    
    var node_watch = LiteGraph.createNode("basic/watch");
    node_watch.pos = [700,200];
    graph.add(node_watch);
    
    node_const.connect(0, node_watch, 0 );
    
    graph.start()
    </script>
    </body>
    </html>
    

    How to code a new Node type

    Here is an example of how to build a node that sums two inputs:

    //node constructor class
    function MyAddNode()
    {
      this.addInput("A","number");
      this.addInput("B","number");
      this.addOutput("A+B","number");
      this.properties = { precision: 1 };
    }
    
    //name to show
    MyAddNode.title = "Sum";
    
    //function to call when the node is executed
    MyAddNode.prototype.onExecute = function()
    {
      var A = this.getInputData(0);
      if( A === undefined )
        A = 0;
      var B = this.getInputData(1);
      if( B === undefined )
        B = 0;
      this.setOutputData( 0, A + B );
    }
    
    //register in the system
    LiteGraph.registerNodeType("basic/sum", MyAddNode );
    

    or you can wrap an existing function:

    function sum(a,b)
    {
       return a+b;
    }
    
    LiteGraph.wrapFunctionAsNode("math/sum",sum, ["Number","Number"],"Number");
    

    Server side

    It also works server-side using NodeJS although some nodes do not work in server (audio, graphics, input, etc).

    var LiteGraph = require("./litegraph.js").LiteGraph;
    
    var graph = new LiteGraph.LGraph();
    
    var node_time = LiteGraph.createNode("basic/time");
    graph.add(node_time);
    
    var node_console = LiteGraph.createNode("basic/console");
    node_console.mode = LiteGraph.ALWAYS;
    graph.add(node_console);
    
    node_time.connect( 0, node_console, 1 );
    
    graph.start()
    

    Projects using it

    webglstudio.org

    WebGLStudio

    MOI Elephant

    MOI Elephant

    Mynodes

    MyNodes

    Utils


    It includes several commands in the utils folder to generate doc, check errors and build minifyed version.

    Demo


    The demo includes some examples of graphs. In order to try them you can visit demo site or install it on your local computer, to do so you need git, node and npm. Given those dependencies are installed, run the following commands to try it out:

    $ git clone git@github.com:jagenjo/litegraph.js.git
    $ cd litegraph.js
    $ npm install
    $ node utils/server.js
    Example app listening on port 80!
    

    Open your browser and point it to http://localhost. You can select demo from the dropdown at the top of the page.

    Feedback


    You can write any feedback to javi.agenjo@gmail.com

    Contributors

    • kriffe
    • rappestad
    • InventivetalentDev
    • NateScarlet
    Show All