Using d3 to generate canvas png in node.js

README.md

In order to generate a raster image with d3 in node.js, you need a canvas context. This is a bare bones example of using a node-based canvas for said context.

index.js

#!/usr/bin/env node

var fs = require("fs"),
    path = require("path"),
    d3 = require("d3"),
    Canvas = require("canvas");

var width = 1000,
    height = 500;

var canvas = new Canvas(width, height),
    context = canvas.getContext("2d");

context.strokeStyle = "rgba(100,0,0,0.5)";
context.beginPath();
context.moveTo(50, height / 2);
context.lineTo(width - 50, height / 2);
context.stroke();

canvas.createPNGStream().pipe(fs.createWriteStream(path.join(__dirname, "canvas.png")));