JavaScript

What is Canvas?

Canvas is an HTML element designed for drawing using JavaScript. It acts as a container for drawing. Like other HTML elements, the Canvas has its own tag and is embedded on the page in the following way:

<canvas id="canvas">Canvas is not supported by your browser</canvas> 

All further operations with Canvas are done using JavaScript. First, we need to create a Canvas object:

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

Then define the Context:

const context = canvas.getContext('2d');

Each Canvas can have only one Context. Multiple calls of getContext for the same Canvas will return a reference to the same Context.

Sprite sheets have been used in game development for many years. In web development it allows you to reduce:

• a number of HTTP requests for downloading many separate images,
• webserver load as a result of fewer requests,
• download time as a combined sprite sheet is smaller than the individual files.

I want to share the approach that I used in my games written with canvas and javascript. I think this is a reusable approach for animating different objects on a canvas.

To demonstrate it, I compiled a Sonic sprite sheet from the "Sonic the Hedgehog 3" game.