RiseupDev/index.html

## index.html
<!DOCTYPE html>
<html>
<head>
  <meta charset="utf-8">
  <title>D3 Drawing</title>
  <script src="https://cdn.jsdelivr.net/d3js/3.5.9/d3.min.js"></script>
</head>
<body>
  <h3>Draw a polygon :D</h3>
  <script>
    // global vars
var dragging = false, drawing = false, startPoint;
var svg = d3.select('body').append('svg')
    .attr('height', 1000)
    .attr('width', 1000);

var points = [], g;

// behaviors
var dragger = d3.behavior.drag()
    .on('drag', handleDrag)
    .on('dragend', function(d){
        dragging = false;
    });

svg.on('mouseup', function(){
    if(dragging) return;
    drawing = true;
    startPoint = [d3.mouse(this)[0], d3.mouse(this)[1]];
    if(svg.select('g.drawPoly').empty()) g = svg.append('g').attr('class', 'drawPoly');
    if(d3.event.target.hasAttribute('is-handle')) {
        closePolygon();
        return;
    };

    points.push(d3.mouse(this));
    g.select('polyline').remove();

    var polyline = g.append('polyline').attr('points', points)
                    .style('fill', 'none')
                    .attr('stroke', '#000');

    for(var i = 0; i < points.length; i++) {
        g.append('circle')
        .attr('cx', points[i][0])
        .attr('cy', points[i][1])
        .attr('r', 4)
        .attr('fill', 'yellow')
        .attr('stroke', '#000')
        .attr('is-handle', 'true')
        .style({cursor: 'pointer'});
    }
});

function closePolygon() {
    svg.select('g.drawPoly').remove();
    var g = svg.append('g');
    g.append('polygon')
    .attr('points', points)
    .style('fill', getRandomColor());
    for(var i = 0; i < points.length; i++) {
        var circle = g.selectAll('circles')
        .data([points[i]])
        .enter()
        .append('circle')
        .attr('cx', points[i][0])
        .attr('cy', points[i][1])
        .attr('r', 4)
        .attr('fill', '#FDBC07')
        .attr('stroke', '#000')
        .attr('is-handle', 'true')
        .style({cursor: 'move'})
        .call(dragger);
    }
    points.splice(0);
    drawing = false;
}

svg.on('mousemove', function() {
    if(!drawing) return;
    var g = d3.select('g.drawPoly');
    g.select('line').remove();
    var line = g.append('line')
                .attr('x1', startPoint[0])
                .attr('y1', startPoint[1])
                .attr('x2', d3.mouse(this)[0] + 2)
                .attr('y2', d3.mouse(this)[1])
                .attr('stroke', '#53DBF3')
                .attr('stroke-width', 1);
})

function handleDrag() {
    if(drawing) return;
    var dragCircle = d3.select(this), newPoints = [], circle;
    dragging = true;
    var poly = d3.select(this.parentNode).select('polygon');
    var circles = d3.select(this.parentNode).selectAll('circle');
    dragCircle
    .attr('cx', d3.event.x)
    .attr('cy', d3.event.y);
    for (var i = 0; i < circles[0].length; i++) {
        circle = d3.select(circles[0][i]);
        newPoints.push([circle.attr('cx'), circle.attr('cy')]);
    }
    poly.attr('points', newPoints);
}

function getRandomColor() {
    var letters = '0123456789ABCDEF'.split('');
    var color = '#';
    for (var i = 0; i < 6; i++) {
        color += letters[Math.floor(Math.random() * 16)];
    }
    return color;
}

  </script>
</body>
</html>
	<!DOCTYPE html>
	<html>
	<head>
	<meta charset="utf-8">
	<title>D3 Drawing</title>
	<script src="https://cdn.jsdelivr.net/d3js/3.5.9/d3.min.js"></script>
	</head>
	<body>
	<h3>Draw a polygon :D</h3>
	<script>
	// global vars
	var dragging = false, drawing = false, startPoint;
	var svg = d3.select('body').append('svg')
	.attr('height', 1000)
	.attr('width', 1000);

	var points = [], g;

	// behaviors
	var dragger = d3.behavior.drag()
	.on('drag', handleDrag)
	.on('dragend', function(d){
	dragging = false;
	});

	svg.on('mouseup', function(){
	if(dragging) return;
	drawing = true;
	startPoint = [d3.mouse(this)[0], d3.mouse(this)[1]];
	if(svg.select('g.drawPoly').empty()) g = svg.append('g').attr('class', 'drawPoly');
	if(d3.event.target.hasAttribute('is-handle')) {
	closePolygon();
	return;
	};

	points.push(d3.mouse(this));
	g.select('polyline').remove();

	var polyline = g.append('polyline').attr('points', points)
	.style('fill', 'none')
	.attr('stroke', '#000');

	for(var i = 0; i < points.length; i++) {
	g.append('circle')
	.attr('cx', points[i][0])
	.attr('cy', points[i][1])
	.attr('r', 4)
	.attr('fill', 'yellow')
	.attr('stroke', '#000')
	.attr('is-handle', 'true')
	.style({cursor: 'pointer'});
	}
	});

	function closePolygon() {
	svg.select('g.drawPoly').remove();
	var g = svg.append('g');
	g.append('polygon')
	.attr('points', points)
	.style('fill', getRandomColor());
	for(var i = 0; i < points.length; i++) {
	var circle = g.selectAll('circles')
	.data([points[i]])
	.enter()
	.append('circle')
	.attr('cx', points[i][0])
	.attr('cy', points[i][1])
	.attr('r', 4)
	.attr('fill', '#FDBC07')
	.attr('stroke', '#000')
	.attr('is-handle', 'true')
	.style({cursor: 'move'})
	.call(dragger);
	}
	points.splice(0);
	drawing = false;
	}

	svg.on('mousemove', function() {
	if(!drawing) return;
	var g = d3.select('g.drawPoly');
	g.select('line').remove();
	var line = g.append('line')
	.attr('x1', startPoint[0])
	.attr('y1', startPoint[1])
	.attr('x2', d3.mouse(this)[0] + 2)
	.attr('y2', d3.mouse(this)[1])
	.attr('stroke', '#53DBF3')
	.attr('stroke-width', 1);
	})

	function handleDrag() {
	if(drawing) return;
	var dragCircle = d3.select(this), newPoints = [], circle;
	dragging = true;
	var poly = d3.select(this.parentNode).select('polygon');
	var circles = d3.select(this.parentNode).selectAll('circle');
	dragCircle
	.attr('cx', d3.event.x)
	.attr('cy', d3.event.y);
	for (var i = 0; i < circles[0].length; i++) {
	circle = d3.select(circles[0][i]);
	newPoints.push([circle.attr('cx'), circle.attr('cy')]);
	}
	poly.attr('points', newPoints);
	}

	function getRandomColor() {
	var letters = '0123456789ABCDEF'.split('');
	var color = '#';
	for (var i = 0; i < 6; i++) {
	color += letters[Math.floor(Math.random() * 16)];
	}
	return color;
	}

	</script>
	</body>
	</html>