D3 Spin Art

This is a sort of interactive version of Rotating Shape Transitions.

You can adjust the rotational speed on the left, select form the color palette on the right, and chose between drawing a line or multiple small circles.

Interesting things start to happen at certain speeds, both with how the lines get drawn and how they appear.

<!DOCTYPE html>
<meta charset="utf-8">
<head>
	<style>
		body {
			background-color:#343633;
		}
		div {
			position: absolute;
			color:#ecf0f1;
		    font-size: 1.17em;
		    font-weight: bold;
		    right: 30px;
		}
		#sliderVal {
			left: 30px;
		}
		input[type=range][orient=vertical] {
			position: absolute;
			writing-mode: bt-lr; /* IE */
			-webkit-appearance: slider-vertical; /* WebKit */
			width: 5px;
			height: 450px;
			left: 30px;
			top: 50px;
		}	
		.palette {
			position: absolute;
			width: 50px;
			height: 450px;
			right: 30px;
			top: 50px;
		}
		.selected {
			stroke: #ecf0f1;
			stroke-width: 5px;
		}
		polyline {
			fill: none;
			stroke: black;
			stroke-width:2px;
		}
</style>
	<script src="//d3js.org/d3.v4.min.js"></script>
</head>
<body>
	<div id="sliderVal">
		Revolutions per minute: 120
	</div>
	<div>
		<form>Draw Style: 
			<input type="radio" name="drawStyle" value="line" checked="checked"> Line 
			<input type="radio" name="drawStyle" value="circle"> Circle
		</form>
	</div>
	<input type="range" id="slider" max=1300 value=120 orient="vertical">
</body>
<script>

var width = Math.max(960, innerWidth),
    	height = Math.max(500, innerHeight);

d3.select("#slider")
		.on("input", function() {
			d3.select("#sliderVal").html("Revolutions per minute: " + this.value)
			rotate(this.value)
		})
	
	var svg = d3.select("body").append("svg")
	    .attr("width", width)
	    .attr("height", height)
	    .append("g")
	    	.attr("transform", "translate(" + width/2 + ", " + height/2 + ")rotate(0)")

var colors = [["#F7DB51"],["#E43D1D"],["#217FBE"],["#3F9F44"],["#7C5289"]]
	var drawColor = colors[0];

var palette = d3.select("body").append("svg")
		.attr("class", "palette");

palette.selectAll("rect")
		.data(colors)
	  .enter().append("rect")
		.attr("width", 40)
		.attr("height", 40)
		.style("fill", function(d) {return d;})
		.attr("transform", function(d, i) {return "translate(5, " + ((i)*50 + 5) + ")"})
		.on("click", function(d) {
			d3.select(".selected").classed("selected", false)
			d3.select(this).classed("selected", true)
			drawColor = d;
		})

palette.select("rect").classed("selected", true)

var platter = svg.append("circle")
	    .attr("r", width)
	    .attr("cx", 0)
	    .attr("cy", 0)
	    .style("fill-opacity", 0)
		.on("mousedown", function() {
			var drawStyle = d3.select('input:checked').attr("value");
			if (drawStyle == "line") {
				var newShape = svg.append("polyline")
					.attr("class", "drawn")
					.style("stroke", drawColor)
					.attr("points", d3.mouse(this) + " ")
		    	
		    	svg.call(d3.drag()
		        	.on("drag", function() {
						newShape.attr("points", newShape.attr("points") + " " + d3.mouse(this) + " ")
		        	}));
			} else if (drawStyle == "circle") {
	    		svg.append("circle")
					.attr("class", "drawn")
					.attr("r", 2)
					.attr("cx", d3.mouse(this)[0])
					.attr("cy", d3.mouse(this)[1])
					.style("fill", drawColor)

svg.call(d3.drag()
		        	.on("drag", function() {
			    		svg.append("circle")
							.attr("class", "drawn")
							.attr("r", 2)
							.attr("cx", d3.mouse(this)[0])
							.attr("cy", d3.mouse(this)[1])
							.style("fill", drawColor)
		        	}));	
			}
		})

var centerDot = svg.append("circle")
		.attr("r", 5)
		.attr("cx", 0)
		.attr("cy", 0)
		.style("fill", "#ecf0f1")

var centerTriangle = svg.append("polygon")
		.attr("points", [[-5,0],[0,10],[5,0]])
		.style("fill", "#ecf0f1")

rotate(120);

function rotate(rpm) {
		if (rpm == 0) {
			svg.interrupt()
		} else {
			var newAngle = svg._groups[0][0].transform.animVal[1].angle + 120;

svg.transition().duration(20000/rpm).ease(d3.easeLinear)
				.attr("transform", "translate(" + width/2 + ", " + height/2 + ")rotate(" + newAngle + ")")
				.on("end", function() {rotate(rpm)})
		}
	}
</script>

https://d3js.org/d3.v4.min.js