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## Analog D3 Clock
A simple animated clock icon made to delight MailChimp users (and folks like [Adam](https://twitter.com/thedigiguru/status/434316427340697600)). On load and refresh, the clock adjusts to the current time.
<div class="d3clock"></div>
### Thanks to all involved:
- [Thierry’s tweet](https://twitter.com/blancpain/statuses/394931135353851904) started it all
- [Eric](https://twitter.com/muntzen) and [Federico](https://twitter.com/fholgado) got the ball rolling
- [Guan](https://twitter.com/gliao) gave a quick Dojo widget walk-through for use across MailChimp
- [Alvaro](https://twitter.com/alvasavi) noticed that the hour-hand wasn’t right and `scaleBetweenHours` helped solve that
- [Caleb](https://twitter.com/calebbritton) designed the previously static clock icon
@import url('https://fonts.googleapis.com/css?family=Open+Sans');
body { font-family: 'Open Sans'; background-color: #f6f6f6; }
.clock { margin: 10% auto; display: block; }
(function () {
// Clock look-n-feel: customize at will!
var width = 360,
height = 360,
strokeWidth = 6,
clockFillColor = "none",
clockBorderColor = "#B7B7B7",
clockHandColor = "#FEBE12",
clockCenterColor = "#FEBE12",
transitionEnabled = 1,
radius = width / 2,
vis, clock, hourPosition, minutePosition, clockhand, hourPositionOffset;
// Set up time
var now = new Date();
var data = [{
'unit': 'minutes',
'value': now.getMinutes()
}, {
'unit': 'hours',
'value': now.getHours()
}];
// Set up Scales
// Map 60 minutes onto a radial 360 degree range.
var scaleMins = d3.scale.linear()
.domain([0, 59 + 59 / 60])
.range([0, 2 * Math.PI]);
// Map 12 hours onto a radial 360 degree range.
var scaleHours = d3.scale.linear()
.domain([0, 11 + 59 / 60])
.range([0, 2 * Math.PI]);
// Every hour, the minute hand moves 360 degrees and the hour hand moves 30 degrees.
// To get the final, accurate hour hand position, the linear movement of the minute hand
// is mapped to a 30 degree radial angle and the resulting angular offset
// is added to the hour hand position (in scaleHours above).
var scaleBetweenHours = d3.scale.linear()
.domain([0, 59 + 59 / 60])
.range([0, Math.PI / 6]);
// Set up SVG
vis = d3.select("div.d3clock")
.append("svg:svg")
.attr("class", "clock")
.attr("width", width)
.attr("height", height);
clock = vis.append("svg:g")
.attr("transform", "translate(" + radius + "," + radius + ")");
// Clock face
clock.append("svg:circle")
.attr("class", "clockface")
.attr("r", radius - strokeWidth)
.attr("fill", clockFillColor)
.attr("stroke", clockBorderColor)
.attr("stroke-width", strokeWidth * 2);
// When animating, set 12 o’clock as the clockhand animation start position
minutePosition = d3.svg.arc()
.innerRadius(0)
.outerRadius((3 / 4) * radius)
.startAngle(0)
.endAngle(0);
hourPosition = d3.svg.arc()
.innerRadius(0)
.outerRadius((1 / 2) * radius)
.startAngle(0)
.endAngle(0);
// When not animating, set the clockhand positions based on time
minutePositionFinal = d3.svg.arc()
.innerRadius(0)
.outerRadius((2 / 3) * radius)
.startAngle(function (d) {
return scaleMins(+d.value);
})
.endAngle(function (d) {
return scaleMins(+d.value);
});
hourPositionFinal = d3.svg.arc()
.innerRadius(0)
.outerRadius((1 / 2) * radius)
.startAngle(function (d) {
return (scaleHours(+d.value % 12) + scaleBetweenHours(hourPositionOffset));
})
.endAngle(function (d) {
return (scaleHours(+d.value % 12) + scaleBetweenHours(hourPositionOffset));
});
// Add clockhands to the clockface
clockhand = clock.selectAll(".clockhand")
.data(data)
.enter()
.append("svg:path")
.attr("class", "clockhand")
.attr("stroke", clockHandColor)
.attr("stroke-width", strokeWidth + 4)
.attr("stroke-linecap", "round")
.attr("stroke-linejoin", "round")
.attr("fill", "none");
// Animate clockhands!
if (transitionEnabled) {
clockhand.attr("d", function (d) {
if (d.unit === "minutes") {
hourPositionOffset = +d.value;
return minutePosition();
} else if (d.unit === "hours") {
return hourPosition();
}
})
.transition()
.delay(333)
.duration(555)
.ease("elastic", 1, 4)
.attrTween("transform", tween);
} else {
clockhand.attr("d", function (d) {
if (d.unit === "minutes") {
hourPositionOffset = +d.value;
return minutePositionFinal(d);
} else if (d.unit === "hours") {
return hourPositionFinal(d);
}
});
}
function tween(d, i, a) {
if (d.unit === "minutes") {
return d3.interpolate("rotate(0)", "rotate(" + (scaleMins(+d.value) * (180 / Math.PI)) + ")");
} else if (d.unit === "hours") {
return d3.interpolate("rotate(0)", "rotate(" + ((scaleHours(+d.value % 12) + scaleBetweenHours(hourPositionOffset)) * (180 / Math.PI)) + ")");
}
}
// Add center dial
return clock.append("svg:circle")
.attr("class", "centerdot")
.attr("r", strokeWidth + 2)
.attr("fill", "#fff")
.attr("stroke", clockCenterColor)
.attr("stroke-width", strokeWidth + 2);
}());
Also see: Tab Triggers