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<!--
music clip from "The Knife": "rock classics"
https://www.youtube.com/watch?v=mwDxtM4Au94
-->
<audio id='music' controls='controls'>
<source src='http://sheriffderek.consulting/audio/mp3/short.mp3' type='audio/mp3' />
</audio>
<div class='item one'>1</div>
<div class='item two'>2</div>
html, body
background: $color
body
padding: 1rem
block()
display: block
width: 40px
height: 40px
border-radius: .3rem
margin: .3rem
padding: .5rem
background: $highlight
.item
block()
&.one
background: alpha(black, .5)
&.two
background: alpha(white, .5)
var thisTrack = document.getElementById('music');
// set audio to loop (optional)
thisTrack.loop = true;
// references to svg objects
var itemOne = document.querySelector('.item.one');
var itemTwo = document.querySelector('.item.two');
var body = document.body;
var $color = '#6cf';
var $highlight = '#f66';
// timeline set up, note that paused is set to true as the playback
// will be controlled by the audio to keep in sync
var timeline1 = new TimelineMax({
paused: true
});
var time = undefined;
// thisTrack.onloadedmetadata = function() {
// time = thisTrack.duration;
// console.log( time );
// }; // I'm not sure why this part isn't getting the duration propertly...
time = 13.81875;
timeline1
.to(itemOne, (time/3), {
x: 150,
color: '#fff'
})
.to(itemOne, (time/3), {
x: 400,
color: $color
})
.to(itemOne, (time/3), {
x: 0,
color: '#fff'
})
;
var timeline2 = new TimelineMax({
paused: true
});
timeline2
.to(itemTwo, (time/3), {
x: 400
})
.to(itemTwo, (time/3), {
x: 150
})
.to(itemTwo, (time/3), {
x: 0
})
;
var timeline3 = new TimelineMax({
paused: true
});
timeline3
.fromTo(body, time, {
backgroundColor: $color
}, {
backgroundColor: $highlight
})
;
// when the music is played, play the animation
thisTrack.onplay = function() {
timeline1.play();
timeline2.play();
timeline3.play();
};
// when the music is paused, pause the animation
thisTrack.onpause = function() {
timeline1.pause();
timeline2.pause();
timeline3.pause();
};
// when the progress bar on the audio element is jumped to a different
// point manually (or automatically), adjust the timeline to match
thisTrack.onseeked = function() {
timeline1.time(thisTrack.currentTime);
timeline2.time(thisTrack.currentTime);
timeline3.time(thisTrack.currentTime);
}
// while the audio is being played, make sure the timelines are in sync
// with the audio (it otherwise appears to go out of sync if, for
// example, the tab is not in focus)
thisTrack.ontimeupdate = function() {
timeline1.time(thisTrack.currentTime);
timeline2.time(thisTrack.currentTime);
timeline3.time(thisTrack.currentTime);
};
Also see: Tab Triggers