Drawing elements

In previous versions of HTML, if you wanted a graphic or image, you had to create it in another application and use the img element to pull it into your document. HTML5 has brought some new elements and features to replace the old elements that allow you to draw your own images in the browser.

canvas

The syntax of the canvas element is as follows:

<canvas height width></canvas>

Attributes

The attributes that are used in the canvas element are as follows:

• height: This is an attribute to set the height
• width: This is an attribute to set the width

Description

The canvas element is used for drawing. You can use JavaScript to draw lines, shapes, and images; pull frames from videos; and use WebGL, to name just a few features. The HTML element is just the canvas (aptly named!) that you use to make a drawing. All of the interaction happens in JavaScript.

Here is an example of a small canvas element:

<canvas height="400" width="400">
    Your browser does not support the canvas element.
</canvas>

svg

The svg element is the Scalable Vector Graphics (SVG) element:

<svg height viewbox width ></svg>

Attributes

The attributes that are used in the svg element are as follows:

• height: This is the attribute that sets the height.
• viewbox: This sets the bounds for the element. It takes four numbers that map to min-x, min-y, width, and height.
• width: This is the attribute that sets the width.

Description

SVG is not a true HTML element. It is its own specification with many elements and attributes. There are books written entirely about SVG. This element is here because you can now create inline SVG in an HTML document. This gives you a lot of flexibility with two-dimensional drawings that images do not give you.

Here is an example that demonstrates the difference between height, width, and viewport. The viewport takes up the bounds of the element, and height and width give the element its size:

<svg xmlns="http://www.w3.org/2000/svg" preserveAspectRatio=""
    width="200" height="100" viewBox="0 0 400 200">
    <rect x="0" y="0" width="400" height="200" fill="yellow" stroke="black" stroke-width="3" />
</svg>