Canvas - FalkorDB Docs

FalkorDB Canvas is a standalone web component for visualizing FalkorDB graphs using force-directed layouts. It is published as an npm package at @falkordb/canvas and powers the graph visualization in FalkorDB Browser.

Features

Force-directed graph layout – Automatic positioning using D3 force simulation with smart collision detection
Multiple layout modes – Switch between force, tree, and radial graph views
Interactive – Click, hover, and right-click interactions on nodes, links, and background
Theme support – Light and dark mode with customizable colors
Performance – Optimized rendering with HTML5 Canvas, including viewport culling and low-zoom draw skipping for large graphs
Loading states – Built-in skeleton loading with pulse animation
Customizable – Colors, sizes, behaviors, and custom rendering functions
TypeScript support – Full type definitions included
Web Component – Works with any framework or vanilla JavaScript
Viewport control – Zoom, pan, and auto-fit functionality

Installation

npm install @falkordb/canvas

Quick Start

Vanilla JavaScript

<!DOCTYPE html>
<html>
<head>
  <title>FalkorDB Canvas Example</title>
</head>
<body>
  <falkordb-canvas id="graph" style="width: 100%; height: 600px;"></falkordb-canvas>

  <script type="module">
    import '@falkordb/canvas';

    const canvas = document.getElementById('graph');

    // Set data
    canvas.setData({
      nodes: [
        { id: 1, labels: ['Person'], color: '#FF6B6B', visible: true, data: { name: 'Alice' } },
        { id: 2, labels: ['Person'], color: '#4ECDC4', visible: true, data: { name: 'Bob' } }
      ],
      links: [
        { id: 1, relationship: 'KNOWS', color: '#999', source: 1, target: 2, visible: true, data: {} }
      ]
    });

    // Configure
    canvas.setConfig({
      width: 800,
      height: 600,
      backgroundColor: '#FFFFFF',
      foregroundColor: '#1A1A1A',
      eventHandlers: {
        onNodeClick: (node) => console.log('Clicked:', node),
      },
    });
  </script>
</body>
</html>

React / TypeScript

import { useEffect, useRef } from 'react';
import '@falkordb/canvas';
import type { FalkorDBCanvas, Data, GraphNode } from '@falkordb/canvas';

function GraphVisualization() {
  const canvasRef = useRef<FalkorDBCanvas | null>(null);

  useEffect(() => {
    const canvas = canvasRef.current;
    if (!canvas) return;

    const data: Data = {
      nodes: [
        { id: 1, labels: ['Person'], color: '#FF6B6B', visible: true, data: { name: 'Alice' } },
        { id: 2, labels: ['Person'], color: '#4ECDC4', visible: true, data: { name: 'Bob' } }
      ],
      links: [
        { id: 1, relationship: 'KNOWS', color: '#999', source: 1, target: 2, visible: true, data: {} }
      ]
    };

    canvas.setData(data);
    canvas.setConfig({
      eventHandlers: {
        onNodeClick: (node: GraphNode) => {
          console.log('Clicked node:', node);
        },
      },
    });
  }, []);

  return (
    <falkordb-canvas 
      ref={canvasRef}
      style={{ width: '100%', height: '600px' }}
    />
  );
}

API

Methods

Method	Description
`setData(data)`	Set the graph data (nodes and links). Automatically triggers layout simulation and loading states.
`getData()`	Get the current graph data in the simplified format.
`setGraphData(data)`	Set graph data in the internal format (with computed properties). Use for better performance when you already have `GraphData` format.
`getGraphData()`	Get the current graph data in the internal format with all computed properties.
`setConfig(config)`	Configure the graph visualization and behavior. Accepts a `ForceGraphConfig` object.
`setWidth(width)`	Set canvas width in pixels.
`setHeight(height)`	Set canvas height in pixels.
`setBackgroundColor(color)`	Set background color (hex or CSS color).
`setForegroundColor(color)`	Set foreground color for text and borders.
`setAnimation(enabled)`	Enable or disable force simulation animation. When disabled, pins all nodes in place.
`setPinOnDragEnd(pin)`	Enable or disable pinning nodes after dragging.
`setLayout(layoutMode)`	Switch layout mode: `'force'`, `'tree'`, or `'radial'`.
`setLayoutOptions(options)`	Update per-layout options (tree, radial, force). Triggers re-layout.
`setDebug(enabled)`	Enable or disable debug logging to console.
`refresh()`	Trigger a repaint after in-place property mutations (visibility, color, size).
`getViewport()`	Get current zoom and center position as `ViewportState`.
`setViewport(viewport)`	Restore a previously saved viewport state.
`getZoom()`	Get current zoom level.
`zoom(zoomLevel)`	Set zoom level.
`zoomToFit(paddingMultiplier, filter)`	Auto-fit all visible nodes in view. Optional padding multiplier and node filter function.
`getGraph()`	Get the underlying force-graph instance for advanced control.
`getCullingStats()`	Get viewport culling statistics (bounds, visible vs total node/link counts).

Configuration Options

Configuration is passed to setConfig() as a ForceGraphConfig object.

Top-Level Options

Option	Default	Description
`width`	window width	Canvas width in pixels
`height`	window height	Canvas height in pixels
`backgroundColor`	`'#FFFFFF'`	Background color
`foregroundColor`	`'#1A1A1A'`	Foreground color for borders and text
`layoutMode`	`'force'`	Layout algorithm: `'force'`, `'tree'`, or `'radial'`
`layoutOptions`	`{}`	Per-layout options (see Layout Modes)
`animation`		Enable or disable layout animation
`captionsKeys`	`[]`	Node property keys to display as labels
`showPropertyKeyPrefix`	`false`	Show property key prefix in node labels
`pinOnDragEnd`	`false`	Pin nodes after dragging
`isNodeSelected`		Function: `(node: GraphNode) => boolean`
`isLinkSelected`		Function: `(link: GraphLink) => boolean`
`linkLineDash`		Function: `(link: GraphLink) => number[]`
`node`		Custom node rendering (see Custom Rendering)
`link`		Custom link rendering (see Custom Rendering)
`largeGraph`		Large-graph optimizations (see Large-Graph Optimizations)

Event Handlers

Option	Description
`onNodeClick`	`(node: GraphNode, event: MouseEvent) => void`
`onNodeRightClick`	`(node: GraphNode, event: MouseEvent) => void`
`onLinkClick`	`(link: GraphLink, event: MouseEvent) => void`
`onLinkRightClick`	`(link: GraphLink, event: MouseEvent) => void`
`onNodeHover`	`(node: GraphNode \| null) => void`
`onNodeDragEnd`	`(node: GraphNode) => void`
`onPinChange`	`(pinned: boolean) => void`
`onLinkHover`	`(link: GraphLink \| null) => void`
`onBackgroundClick`	`(event: MouseEvent) => void`
`onBackgroundRightClick`	`(event: MouseEvent) => void`
`onZoom`	`(transform: Transform) => void`
`onEngineStop`	`() => void`
`onLayoutChange`	`(layout: LayoutMode) => void`

Layout Modes

Use layoutMode in setConfig to choose the graph view style:

Force (default)

The default physics-based layout using D3 force simulation with configurable physics parameters.

Tree

canvas.setConfig({
  layoutMode: 'tree',
  layoutOptions: {
    tree: {
      direction: 'lr',      // 'lr' | 'rl' | 'td' | 'bu'
      levelDistance: 180,
      nodeSpacing: 110
    }
  }
});

Radial

canvas.setConfig({
  layoutMode: 'radial',
  layoutOptions: {
    radial: {
      direction: 'out',   // 'out' | 'in'
      levelDistance: 130
    }
  }
});

Data Types

Node

Property	Default	Description
`id`	required	Unique identifier for the node
`labels`	required	Array of label names for the node
`color`	required	Node color (hex or CSS color)
`visible`	required	Whether the node is visible
`size`	`9`	Node radius (world units)
`caption`	`'id'`	Property key to use from the data for display text
`data`	required	Node properties as key-value pairs

Link

Property	Default	Description
`id`	required	Unique identifier for the link
`relationship`	required	Label displayed on the link
`color`	required	Link color (hex or CSS color)
`source`	required	Source node ID
`target`	required	Target node ID
`visible`	required	Whether the link is visible
`data`	required	Link properties as key-value pairs

Custom Rendering

You can provide custom rendering functions for nodes and links:

canvas.setConfig({
  node: {
    nodeCanvasObject: (node: GraphNode, ctx: CanvasRenderingContext2D) => {
      // Custom node drawing logic
      ctx.fillStyle = node.color;
      ctx.fillRect(node.x! - 5, node.y! - 5, 10, 10);
    },
    nodePointerAreaPaint: (node: GraphNode, color: string, ctx: CanvasRenderingContext2D) => {
      // Define clickable area
      ctx.fillStyle = color;
      ctx.fillRect(node.x! - 5, node.y! - 5, 10, 10);
    }
  },
  link: {
    linkCanvasObject: (link: GraphLink, ctx: CanvasRenderingContext2D) => {
      // Custom link drawing logic
    },
    linkPointerAreaPaint: (link: GraphLink, color: string, ctx: CanvasRenderingContext2D) => {
      // Define clickable area for link
    }
  }
});

The node-mode and link-mode HTML attributes control how custom rendering combines with default rendering:

<falkordb-canvas 
  node-mode="replace"
  link-mode="after">
</falkordb-canvas>

replace (default for nodes) – Uses custom rendering exclusively
before – Renders custom content before default rendering
after (default for links) – Renders custom content after default rendering

Large-Graph Optimizations

For graphs with thousands of nodes and links, configure viewport culling and low-zoom draw skipping:

canvas.setConfig({
  largeGraph: {
    viewportPadding: 100,
    lowZoomThreshold: 0.4,
    skipLabelsAtLowZoom: true,
    skipArrowsAtLowZoom: true,
    skipLinkLabelsAtLowZoom: true,
  }
});

Option	Default	Description
`enabled`	`true`	Master switch for large-graph optimizations
`viewportPadding`	`0`	World-unit padding around the visible viewport
`lowZoomThreshold`	`1`	Zoom level below which expensive details are skipped
`skipLabelsAtLowZoom`	`true`	Skip node labels at low zoom
`skipArrowsAtLowZoom`	`true`	Skip link arrowheads at low zoom
`skipLinkLabelsAtLowZoom`	`true`	Skip link relationship labels at low zoom

Utility Functions

The package exports utility functions for data manipulation:

import {
  dataToGraphData,
  graphDataToData,
  getNodeDisplayText,
  getNodeDisplayKey,
  wrapTextForCircularNode
} from '@falkordb/canvas';

// Convert between formats
const graphData = dataToGraphData(data);
const simpleData = graphDataToData(graphData);

// Get display text for a node
const text = getNodeDisplayText(node);

// Wrap text for circular nodes
const [line1, line2] = wrapTextForCircularNode(ctx, text, radius);

Performance Tips

Large graphs – Disable animation (setAnimation(false)) once the layout stabilizes
Static graphs – Use a deterministic layout (setLayout('tree')) to avoid simulation overhead
Custom rendering – Optimize your custom nodeCanvasObject and linkCanvasObject functions
Viewport – Use getViewport() and setViewport() to preserve the user’s view when updating data
Very large graphs – Enable viewport culling via the largeGraph option

Browser Support

Chrome / Edge (latest)
Firefox (latest)
Safari (latest)

Requires support for Web Components (Custom Elements), ES Modules, Shadow DOM, and HTML5 Canvas.

​Features

​Installation

​Quick Start

​Vanilla JavaScript

​React / TypeScript

​API

​Methods

​Configuration Options

​Top-Level Options

​Event Handlers

​Layout Modes

​Force (default)

​Tree

​Radial

​Data Types

​Node

​Link

​Custom Rendering

​Large-Graph Optimizations

​Utility Functions

​Performance Tips

​Browser Support

​Links