Web Animation using JavaScript: Develop & Design (Develop and Design)

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Chapter 6. Scalable Vector Graphics Primer


Since an in-depth tutorial on Scalable Vector Graphics (SVG) could easily comprise a
book of its own, this chapter simply serves as an introduction to the topic. The goal is to
equip you with enough knowledge to be comfortable animating SVG elements and to
know where to go next to continue your learning.


Creating images through code


An SVG element is a type of DOM element that borrows the syntax of the HTML
elements you’re already familiar with to define arbitrary shapes. SVG elements differ
from HTML elements in that they have unique tags, attributes, and behaviors that allow
them to define graphic shapes. Put another way, SVGs let you to create images through
code. This is a tremendously powerful concept because it means you can
programmatically style and animate these shapes using JavaScript and CSS. In addition
SVG offers many other benefits:


    SVG compresses  incredibly  well.   Graphics    defined in  SVG have    smaller file    sizes
than their PNG/JPEG equivalents, which can greatly improve site load times.
SVG graphics scale to any resolution without a loss of clarity. Unlike standard image
formats, they look razor sharp across all devices—say good-bye to blurry images on
mobile screens.
Like HTML elements, SVG elements can be assigned event handlers that respond to
a user’s input, which means that the graphics on your page can be made interactive.
If you so desired, all the buttons on your site could be turned into animated graphics.
Many photo-editing apps (including Adobe Photoshop, Sketch, and Inkscape) let
you export your design work into SVG format for quick copying and pasting into
HTML. So, even if you don’t consider yourself an artist, you can leverage third-
party applications to do the designing for you.
In short, SVGs are an amazing graphics solution. Let’s dive in!

SVG markup


SVG elements are defined within a parent container. Specifying the width and
height dimensions of container element defines the canvas that your SVG graphics render
upon:


Click here to view code image
<svg version=“1.1” width=“500” height=“500”
xmlns=“http://www.w3.org/2000/svg”>





Within , you can insert SVG shape elements of varying sorts. The above
example has a circle element followed by a rect (rectangle) element. As with normal
HTML elements, SVG elements accept height and width attributes, which are used
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