Breather

Taking a little breather here; the svg circus site below is useful
for seeing how complex animations get coded. The one thing I hadn't used was
the function requestAnimationFrame(). It is a request to theWindow object
that is used for javascript (apparently, easier on the browser), for a refresh
of the animation at every repaint (60 times per second). Instead of setInterva().

A simple example on CodePen:

https://codepen.io/chriscoyier/pen/ltseg



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jquery is rather simple to use. One needs to add a reference to an online source
of the library between script tags in the head of the document; there is no
requirement to call the jQuery scripts in the body of the document, other than CSS rules.
There are two main sources for the library: Google and Microsoft.

                                  

source: W3 Schools