Skip to content

Instantly share code, notes, and snippets.

@nbremer

nbremer/.block

Last active November 3, 2023 18:51
Show Gist options
  • Star 3 You must be signed in to star a gist
  • Fork 2 You must be signed in to fork a gist
  • Save nbremer/326fb6de768e85261bfd47aa1f497863 to your computer and use it in GitHub Desktop.
Save nbremer/326fb6de768e85261bfd47aa1f497863 to your computer and use it in GitHub Desktop.
Download ZIP
Brushable Horizontal Bar Chart - IV
Raw
.block
height: 540
Raw
README.md

Although there visually seems no difference between this brushable horizontal bar chart and versions I, II, and III, this one is actually build on a different principle. And it is much, much better than the previous 3 versions in terms of UX, so just ignore those others :) (and as a bonus, there is way less code needed)

In this version, when you scroll your mouse, the bars in the big chart slide across the screen without any transitions.

As a note, there is no x scale adjustment in this version. Check out version V for x scale adjustment

The idea for this came from a tweet by Robert Monfera and an answer on stackOverflow by AmeliaBR helped me figure out the first part.

You have the option to adjust how many bars you're seeing by adjusting the size of the little box on the right mini chart. You can also move the box and see the bars that you've selected appear in a bigger form on the left. Moving can be done either by grabbing and moving the box or scrolling.

For a bit more background, you can read my mini-blog about it Brushable & interactive bar chart in d3.js

Raw
index.html
<!DOCTYPE html>
<head>
<meta charset="utf-8">
<title>Brushable bar chart - Horizontal - IV</title>
<!-- Google fonts -->
<link href='https://fonts.googleapis.com/css?family=Open+Sans:300,400' rel='stylesheet' type='text/css'>
<!-- <script src="d3.v3.js"></script> -->
<script src="//d3js.org/d3.v3.min.js"></script>
<style>
body {
font-size: 10px;
font-family: 'Open Sans', sans-serif;
font-weight: 400;
text-align: center;
}
#title {
font-size: 20px;
padding-bottom: 10px;
padding-top: 20px;
font-weight: 300;
}
#explanation {
font-size: 12px;
max-width: 620px;
margin: 0 auto;
padding-top: 10px;
color: #ababab;
font-weight: 300;
}
.y.axis line {
fill: none;
}
.x.axis line {
fill: none;
stroke: #e0e0e0;
shape-rendering: crispEdges;
}
.axis path {
display: none;
}
.brush .extent {
fill-opacity: .125;
shape-rendering: crispEdges;
}
.resize {
display: inline !important; /* show when empty */
fill: #7A7A7A;
fill-opacity: 1;
stroke: #7A7A7A;
stroke-width: 2px;
}
.bar {
/*shape-rendering: crispEdges;*/
}
</style>
</head>
<body>
<div id="title">Brushable horizontal bar chart - IV</div>
<div id="chart"></div>
<div id="explanation">You can see more or less of the total bar chart on the left by either dragging the box in the mini chart on the right or by scrolling your mouse. You can also click anywhere in the mini chart to center the box on that region. And you can increase and decrease the size of the box by dragging the top or bottom handle up or down.</div>
<script>
var data = [],
svg,
defs,
gBrush,
brush,
main_xScale,
mini_xScale,
main_yScale,
mini_yScale,
main_yZoom,
main_xAxis,
main_yAxis,
mini_width,
textScale;
init();
function init() {
//Create the random data
for (var i = 0; i < 40; i++) {
var my_object = {};
my_object.key = i;
my_object.country = makeWord();
my_object.value = Math.floor(Math.random() * 600);
data.push(my_object);
}//for i
data.sort(function(a,b) { return b.value - a.value; });
/////////////////////////////////////////////////////////////
///////////////// Set-up SVG and wrappers ///////////////////
/////////////////////////////////////////////////////////////
//Added only for the mouse wheel
var zoomer = d3.behavior.zoom()
.on("zoom", null);
var main_margin = {top: 10, right: 10, bottom: 30, left: 100},
main_width = 500 - main_margin.left - main_margin.right,
main_height = 400 - main_margin.top - main_margin.bottom;
var mini_margin = {top: 10, right: 10, bottom: 30, left: 10},
mini_height = 400 - mini_margin.top - mini_margin.bottom;
mini_width = 100 - mini_margin.left - mini_margin.right;
svg = d3.select("#chart").append("svg")
.attr("class", "svgWrapper")
.attr("width", main_width + main_margin.left + main_margin.right + mini_width + mini_margin.left + mini_margin.right)
.attr("height", main_height + main_margin.top + main_margin.bottom)
.call(zoomer)
.on("wheel.zoom", scroll)
//.on("mousewheel.zoom", scroll)
//.on("DOMMouseScroll.zoom", scroll)
//.on("MozMousePixelScroll.zoom", scroll)
//Is this needed?
.on("mousedown.zoom", null)
.on("touchstart.zoom", null)
.on("touchmove.zoom", null)
.on("touchend.zoom", null);
var mainGroup = svg.append("g")
.attr("class","mainGroupWrapper")
.attr("transform","translate(" + main_margin.left + "," + main_margin.top + ")")
.append("g") //another one for the clip path - due to not wanting to clip the labels
.attr("clip-path", "url(#clip)")
.style("clip-path", "url(#clip)")
.attr("class","mainGroup")
var miniGroup = svg.append("g")
.attr("class","miniGroup")
.attr("transform","translate(" + (main_margin.left + main_width + main_margin.right + mini_margin.left) + "," + mini_margin.top + ")");
var brushGroup = svg.append("g")
.attr("class","brushGroup")
.attr("transform","translate(" + (main_margin.left + main_width + main_margin.right + mini_margin.left) + "," + mini_margin.top + ")");
/////////////////////////////////////////////////////////////
////////////////////// Initiate scales //////////////////////
/////////////////////////////////////////////////////////////
main_xScale = d3.scale.linear().range([0, main_width]);
mini_xScale = d3.scale.linear().range([0, mini_width]);
main_yScale = d3.scale.ordinal().rangeBands([0, main_height], 0.4, 0);
mini_yScale = d3.scale.ordinal().rangeBands([0, mini_height], 0.4, 0);
//Based on the idea from: http://stackoverflow.com/questions/21485339/d3-brushing-on-grouped-bar-chart
main_yZoom = d3.scale.linear()
.range([0, main_height])
.domain([0, main_height]);
//Create x axis object
main_xAxis = d3.svg.axis()
.scale(main_xScale)
.orient("bottom")
.ticks(4)
//.tickSize(0)
.outerTickSize(0);
//Add group for the x axis
d3.select(".mainGroupWrapper").append("g")
.attr("class", "x axis")
.attr("transform", "translate(" + 0 + "," + (main_height + 5) + ")");
//Create y axis object
main_yAxis = d3.svg.axis()
.scale(main_yScale)
.orient("left")
.tickSize(0)
.outerTickSize(0);
//Add group for the y axis
mainGroup.append("g")
.attr("class", "y axis")
.attr("transform", "translate(-5,0)");
/////////////////////////////////////////////////////////////
/////////////////////// Update scales ///////////////////////
/////////////////////////////////////////////////////////////
//Update the scales
main_xScale.domain([0, d3.max(data, function(d) { return d.value; })]);
mini_xScale.domain([0, d3.max(data, function(d) { return d.value; })]);
main_yScale.domain(data.map(function(d) { return d.country; }));
mini_yScale.domain(data.map(function(d) { return d.country; }));
//Create the visual part of the y axis
d3.select(".mainGroup").select(".y.axis").call(main_yAxis);
d3.select(".mainGroupWrapper").select(".x.axis").call(main_xAxis);
/////////////////////////////////////////////////////////////
///////////////////// Label axis scales /////////////////////
/////////////////////////////////////////////////////////////
textScale = d3.scale.linear()
.domain([15,50])
.range([12,6])
.clamp(true);
/////////////////////////////////////////////////////////////
///////////////////////// Create brush //////////////////////
/////////////////////////////////////////////////////////////
//What should the first extent of the brush become - a bit arbitrary this
var brushExtent = Math.max( 1, Math.min( 20, Math.round(data.length*0.2) ) );
brush = d3.svg.brush()
.y(mini_yScale)
.extent([mini_yScale(data[0].country), mini_yScale(data[brushExtent].country)])
.on("brush", brushmove)
//.on("brushend", brushend);
//Set up the visual part of the brush
gBrush = d3.select(".brushGroup").append("g")
.attr("class", "brush")
.call(brush);
gBrush.selectAll(".resize")
.append("line")
.attr("x2", mini_width);
gBrush.selectAll(".resize")
.append("path")
.attr("d", d3.svg.symbol().type("triangle-up").size(20))
.attr("transform", function(d,i) {
return i ? "translate(" + (mini_width/2) + "," + 4 + ") rotate(180)" : "translate(" + (mini_width/2) + "," + -4 + ") rotate(0)";
});
gBrush.selectAll("rect")
.attr("width", mini_width);
//On a click recenter the brush window
gBrush.select(".background")
.on("mousedown.brush", brushcenter)
.on("touchstart.brush", brushcenter);
///////////////////////////////////////////////////////////////////////////
/////////////////// Create a rainbow gradient - for fun ///////////////////
///////////////////////////////////////////////////////////////////////////
defs = svg.append("defs")
//Create two separate gradients for the main and mini bar - just because it looks fun
createGradient("gradient-rainbow-main", "60%");
createGradient("gradient-rainbow-mini", "13%");
//Add the clip path for the main bar chart
defs.append("clipPath")
.attr("id", "clip")
.append("rect")
.attr("x", -main_margin.left)
.attr("width", main_width + main_margin.left)
.attr("height", main_height);
/////////////////////////////////////////////////////////////
/////////////// Set-up the mini bar chart ///////////////////
/////////////////////////////////////////////////////////////
//The mini brushable bar
//DATA JOIN
var mini_bar = d3.select(".miniGroup").selectAll(".bar")
.data(data, function(d) { return d.key; });
//UDPATE
mini_bar
.attr("width", function(d) { return mini_xScale(d.value); })
.attr("y", function(d,i) { return mini_yScale(d.country); })
.attr("height", mini_yScale.rangeBand());
//ENTER
mini_bar.enter().append("rect")
.attr("class", "bar")
.attr("x", 0)
.attr("width", function(d) { return mini_xScale(d.value); })
.attr("y", function(d,i) { return mini_yScale(d.country); })
.attr("height", mini_yScale.rangeBand())
.style("fill", "url(#gradient-rainbow-mini)");
//EXIT
mini_bar.exit()
.remove();
//Start the brush
gBrush.call(brush.event);
}//init
//Function runs on a brush move - to update the big bar chart
function update() {
/////////////////////////////////////////////////////////////
////////// Update the bars of the main bar chart ////////////
/////////////////////////////////////////////////////////////
//DATA JOIN
var bar = d3.select(".mainGroup").selectAll(".bar")
.data(data, function(d) { return d.key; });
//UPDATE
bar
.attr("x", 0)
.attr("width", function(d) { return main_xScale(d.value); })
.attr("y", function(d,i) { return main_yScale(d.country); })
.attr("height", main_yScale.rangeBand());
//ENTER
bar.enter().append("rect")
.attr("class", "bar")
.style("fill", "url(#gradient-rainbow-main)")
.attr("x", 0)
.attr("width", function(d) { return main_xScale(d.value); })
.attr("y", function(d,i) { return main_yScale(d.country); })
.attr("height", main_yScale.rangeBand());
//EXIT
bar.exit()
.remove();
}//update
/////////////////////////////////////////////////////////////
////////////////////// Brush functions //////////////////////
/////////////////////////////////////////////////////////////
//First function that runs on a brush move
function brushmove() {
var extent = brush.extent();
//Reset the part that is visible on the big chart
var originalRange = main_yZoom.range();
main_yZoom.domain( extent );
/////////////////////////////////////////////////////////////
///////////////////// Update the axis ///////////////////////
/////////////////////////////////////////////////////////////
//Update the domain of the x & y scale of the big bar chart
main_yScale.domain(data.map(function(d) { return d.country; }));
main_yScale.rangeBands( [ main_yZoom(originalRange[0]), main_yZoom(originalRange[1]) ], 0.4, 0);
//Update the y axis of the big chart
d3.select(".mainGroup")
.select(".y.axis")
.call(main_yAxis);
/////////////////////////////////////////////////////////////
/////////////// Update the mini bar fills ///////////////////
/////////////////////////////////////////////////////////////
//Update the colors within the mini bar chart
var selected = mini_yScale.domain()
.filter(function(d) { return (extent[0] - mini_yScale.rangeBand() + 1e-2 <= mini_yScale(d)) && (mini_yScale(d) <= extent[1] - 1e-2); });
//Update the colors of the mini chart - Make everything outside the brush grey
d3.select(".miniGroup").selectAll(".bar")
.style("fill", function(d, i) { return selected.indexOf(d.country) > -1 ? "url(#gradient-rainbow-mini)" : "#e0e0e0"; });
//Update the label size
d3.selectAll(".y.axis text")
.style("font-size", textScale(selected.length));
//Update the big bar chart
update();
}//brushmove
/////////////////////////////////////////////////////////////
////////////////////// Click functions //////////////////////
/////////////////////////////////////////////////////////////
//Based on http://bl.ocks.org/mbostock/6498000
//What to do when the user clicks on another location along the brushable bar chart
function brushcenter() {
var target = d3.event.target,
extent = brush.extent(),
size = extent[1] - extent[0],
range = mini_yScale.range(),
y0 = d3.min(range) + size / 2,
y1 = d3.max(range) + mini_yScale.rangeBand() - size / 2,
center = Math.max( y0, Math.min( y1, d3.mouse(target)[1] ) );
d3.event.stopPropagation();
gBrush
.call(brush.extent([center - size / 2, center + size / 2]))
.call(brush.event);
}//brushcenter
/////////////////////////////////////////////////////////////
///////////////////// Scroll functions //////////////////////
/////////////////////////////////////////////////////////////
function scroll() {
//Mouse scroll on the mini chart
var extent = brush.extent(),
size = extent[1] - extent[0],
range = mini_yScale.range(),
y0 = d3.min(range),
y1 = d3.max(range) + mini_yScale.rangeBand(),
dy = d3.event.deltaY,
topSection;
if ( extent[0] - dy < y0 ) { topSection = y0; }
else if ( extent[1] - dy > y1 ) { topSection = y1 - size; }
else { topSection = extent[0] - dy; }
//Make sure the page doesn't scroll as well
d3.event.stopPropagation();
d3.event.preventDefault();
gBrush
.call(brush.extent([ topSection, topSection + size ]))
.call(brush.event);
}//scroll
/////////////////////////////////////////////////////////////
///////////////////// Helper functions //////////////////////
/////////////////////////////////////////////////////////////
//Create a gradient
function createGradient(idName, endPerc) {
var coloursRainbow = ["#EFB605", "#E9A501", "#E48405", "#E34914", "#DE0D2B", "#CF003E", "#B90050", "#A30F65", "#8E297E", "#724097", "#4F54A8", "#296DA4", "#0C8B8C", "#0DA471", "#39B15E", "#7EB852"];
defs.append("linearGradient")
.attr("id", idName)
.attr("gradientUnits", "userSpaceOnUse")
.attr("x1", "0%").attr("y1", "0%")
.attr("x2", endPerc).attr("y2", "0%")
.selectAll("stop")
.data(coloursRainbow)
.enter().append("stop")
.attr("offset", function(d,i) { return i/(coloursRainbow.length-1); })
.attr("stop-color", function(d) { return d; });
}//createGradient
//Function to generate random strings of 5 letters - for the demo only
function makeWord() {
var possible_UC = "ABCDEFGHIJKLMNOPQRSTUVWXYZ";
var text = possible_UC.charAt(Math.floor(Math.random() * possible_UC.length));
var possible_LC = "abcdefghijklmnopqrstuvwxyz";
for( var i=0; i < 5; i++ )
text += possible_LC.charAt(Math.floor(Math.random() * possible_LC.length));
return text;
}//makeWord
</script>
</body>
</html>
Sign up for free to join this conversation on GitHub. Already have an account? Sign in to comment