D3.js is a JavaScript library for producing dynamic, interactive data visualizations in web browsers. It makes use of Scalable Vector Graphics, HTML5, and Cascading Style Sheets standards.
The geoGringorten() function in d3.js is used to draw the Gringorten square equal-area projection, rearranged to give each hemisphere an entire square.
Syntax:
d3.geoGringorten()
Parameters: This method does not accept any parameters.
Return Value: This method creates  Gringorten square equal-area projection. from given json data.
Example 1: The following example makes  Gringorten  projection of world with center at (0, 0) and no rotation.
<!DOCTYPE html> < html lang = "en" >   < head >     < meta charset = "UTF-8" />     < meta name = "viewport" content =         "width=device-width, initial-scale=1.0" />     < script src =     </ script > </ head >   < body >     < div style = "width:700px; height:500px;" >         < center >             < h3 style = "color:black" ></ h3 >         </ center >         < svg width = "600" height = "450" ></ svg >     </ div >       < script >         var svg = d3.select("svg"),             width = +svg.attr("width"),             height = +svg.attr("height");           // Gringorten projection         // Center(0, 0) with 0 rotation         var gfg = d3.geoGringorten()             .scale(width / 1.5 / Math.PI)             .rotate([0, 0])             .center([0, 0])             .translate([width / 2, height / 2])           // Loading the json data         // Used json file stored at:         // https://raw.githubusercontent.com/janasayantan         // /datageojson/master/world.json         var myURL = "https://raw.githubusercontent.com/"             + "janasayantan/datageojson/master/world.json"           d3.json(myURL, function (data) {               // Draw the map             svg.append("g")                 .selectAll("path")                 .data(data.features)                 .enter().append("path")                 .attr("fill", "SlateBlue")                 .attr("d", d3.geoPath()                     .projection(gfg)                 )                 .style("stroke", "#ffff")         })     </ script > </ body >   </ html > |
Output:
Gringorten projection with no rotation and centered at (0, 0)
Example 2: The following example makes Gringorten projection of world after customizing the center and rotation.
<!DOCTYPE html> < html lang = "en" >   < head >     < meta charset = "UTF-8" />     < meta name = "viewport" content =         "width=device-width, initial-scale=1.0" />     < script src =     </ script > </ head >   < body >     < div style = "width:700px; height:600px;" >         < center >             < h3 style = "color:black" ></ h3 >         </ center >         < svg width = "700" height = "400" > </ svg >     </ div >       < script >         var svg = d3.select("svg"),             width = +svg.attr("width"),             height = +svg.attr("height");           // Gringorten projection         // Center(-20, 20) and 90 degree         // rotation w.r.t Y axis         var gfg = d3.geoGringorten()             .scale(width / 1.5 / Math.PI)             .rotate([90, 0])             .center([-20, 20])             .translate([width / 2, height / 2])           // Loading the json data         // Used json file stored at:         // https://raw.githubusercontent.com/janasayantan         // /datageojson/master/world.json         var myURL = "https://raw.githubusercontent.com/"             + "janasayantan/datageojson/master/world.json"           d3.json(myURL, function (data) {               // Draw the map             svg.append("g")                 .selectAll("path")                 .data(data.features)                 .enter().append("path")                 .attr("fill", "SlateGrey")                 .attr("d", d3.geoPath()                     .projection(gfg)                 )                 .style("stroke", "#ffff")         })     </ script > </ body >   </ html > |
Output:
Gringorten projection with 90 degree rotation w.r.t  Y axis  and centered at (-20, 20)