Getting started

Getting started with CanvasPainter.js is simple. After setting up an HTML <canvas> element, you can initialize it with a single method call. From there, you can start adding shapes to the canvas, which will automatically render and update as their properties change or you render shapes manually.

Initialize the canvas

First, ensure that you have a <canvas> element in your HTML with an id:

<canvas id="myCanvas"></canvas>

After you've added the canvas element to your HTML, you can initialize it using the init() method:

import { Canvas } from '@avolutions/canvas-painter';

const canvas = Canvas.init('myCanvas');

Create a shape

Next you create shapes and draw them on the canvas. You can either use the built-in shapes or create your own.

A shape is created by simple create a new object instance of it, e.g. Rectangle:

import { Rectangle } from '@avolutions/canvas-painter';

const rectangle = new Rectangle(50, 50, 25, 75); // x, y, width, height

Draw shape manually

You can manually draw the rectangle to the canvas using Canvas.draw() method. This is useful when you only want to render the canvas once or on-demand.

import { Canvas, Rectangle } from '@avolutions/canvas-painter';

const canvas = Canvas.init('myCanvas');
const rectangle = new Rectangle(50, 50, 25, 75); // x, y, width, height

canvas.draw(rectangle);

Watch shapes

A more advanced way to draw the shape is to let the canvas watch it and (re-)draws it every time the shape changes. This allows you to simply modify the shape object without caring about rerendering of the canvas. To do so, use the Canvas.watch() method.

import { Canvas, Rectangle } from '@avolutions/canvas-painter';

const canvas = Canvas.init('myCanvas');
const rectangle = new Rectangle(50, 50, 25, 75); // x, y, width, height

canvas.watch(rectangle); // this will draw the rectangle

rectangle.width = 100; // this will redraw the rectangle with the new width

Using the JavaScript Canvas API

In addition to using CanvasPainter.js built-in drawing methods, you have full access to the official Canvas 2D API through Canvas.context. This allows you to use any method from the standard Canvas/Context API directly:

import { Canvas } from '@avolutions/canvas-painter';

// Access the 2D rendering context
const canvas = Canvas.init('myCanvas');
const ctx = canvas.context;

// Use standard Canvas API methods
ctx.fillStyle = 'blue';
ctx.fillRect(50, 50, 100, 100);

ctx.strokeStyle = 'red';
ctx.lineWidth = 5;
ctx.strokeRect(150, 150, 100, 100);

// Draw text
ctx.font = '20px Arial';
ctx.fillText('Hello, Canvas!', 200, 200);

You can explore the full Canvas API documentation here.