function streamgraph($selector, $slider) {
/* Constants */
var VMARGIN = 3,
YEARSHEIGHT = 20,
STARTTIME = new Date(2007,6,1),
ENDTIME = new Date(),
CURVE = .3,
COLORS = [ "#943a23", "#fbee97", "#cfbb95", "#da9761", "#ba5036" ],
SELECTEDCOLOR = "#c51810";
/* Generating random data */
var data = [],
clustercount = 12,
slicecount = 20,
maxdata = 10,
randpart = 4,
dampfactor = .333;
for (var i = 0; i < clustercount; i++) {
var line = [],
peaktime = Math.floor(Math.random() * slicecount);
for (var j = 0; j < slicecount; j++) {
var point = Math.min(maxdata, Math.max(0, (Math.random() - .5) * randpart + Math.max(0, maxdata * (1 - dampfactor * Math.abs(j - peaktime)))));
line.push(point);
}
data.push(line);
}
/* Calculating scales and positions */
var width = $selector.width(),
height = $selector.height(),
transp = _.zip.apply( _, data ),
cumulative = _(transp).map(function(column) {
var total = 0;
return _(column).map(function(point) {
return total += point;
});
}),
sums = _(cumulative).map(function(column) {
return _(column).last();
})
maxcol = _(sums).max(),
streamheight = height - YEARSHEIGHT,
yscale = (streamheight - 2 * VMARGIN) / maxcol,
centery = streamheight / 2,
xscale = width / (transp.length - 1),
txscale = width / (ENDTIME - STARTTIME),
coords = _(data).map(function(line, lineindex) {
return _(line).map(function(point, colindex) {
var lowercumul = lineindex ? cumulative[colindex][lineindex - 1] : 0,
uppercumul = cumulative[colindex][lineindex];
return {
data: point,
x: xscale * colindex,
lowery: centery + yscale * ( ( sums[colindex] / 2 ) - lowercumul ),
uppery: centery + yscale * ( ( sums[colindex] / 2 ) - uppercumul ),
}
});
}),
paths = _(coords).map(function(line) {
var lowerline = _(line).reduce(function(path, point, colindex) {
var res = path;
if (colindex) {
res += "," + (point.x - CURVE * xscale) + "," + point.lowery + "," + point.x + "," + point.lowery;
} else {
res += "M" + point.x + "," + point.lowery;
}
if (colindex < line.length - 1) {
res += "C" + (point.x + CURVE * xscale) + "," + point.lowery;
}
return res;
}, "");
var upperline = _(line).reduceRight(function(path, point, colindex) {
var res = path;
if (colindex < line.length - 1) {
res += "," + (point.x + CURVE * xscale) + "," + point.uppery + "," + point.x + "," + point.uppery;
} else {
res += "L" + point.x + "," + point.uppery;
}
if (colindex) {
res += "C" + (point.x - CURVE * xscale) + "," + point.uppery;
}
return res;
}, "");
return lowerline + upperline;
});
/* Drawing streamgraph*/
var paper = new Raphael($selector[0]);
_(paths).each(function(path, index) {
var color = COLORS[index % COLORS.length],
path = paper.path(path);
path.attr({
stroke: "none",
fill: color
}).mouseover(function() {
path.attr({
fill: SELECTEDCOLOR
});
}).mouseout(function() {
path.attr({
fill: color
})
});
});
/* Drawing years */
paper.path("M0," + (height - YEARSHEIGHT) + "," + width + "," + (height - YEARSHEIGHT))
var lastyear = ENDTIME.getFullYear();
for (var i = STARTTIME.getFullYear(); i <= lastyear; i++) {
var x = txscale * (new Date(i,0,1) - STARTTIME);
paper.path("M" + x + ",0," + x + "," + height);
var x = txscale * (new Date(i,6,1) - STARTTIME);
paper.text(x, height - .5 * YEARSHEIGHT, i)
.attr({
"text-anchor": "middle",
"font-family": "Times New Roman, serif",
"font-size": "14px"
});
}
}
$(function() {
streamgraph($(".streamgraph"), $("#slider-range"));
})