diff -r efd9c589177a -r c0b4a8b5a012 toolkit/javascript/d3/src/geo/bonne.js --- /dev/null Thu Jan 01 00:00:00 1970 +0000 +++ b/toolkit/javascript/d3/src/geo/bonne.js Thu Apr 10 14:20:23 2014 +0200 @@ -0,0 +1,70 @@ +d3.geo.bonne = function() { + var scale = 200, + translate = [480, 250], + x0, // origin longitude in radians + y0, // origin latitude in radians + y1, // parallel latitude in radians + c1; // cot(y1) + + function bonne(coordinates) { + var x = coordinates[0] * d3_geo_radians - x0, + y = coordinates[1] * d3_geo_radians - y0; + if (y1) { + var p = c1 + y1 - y, E = x * Math.cos(y) / p; + x = p * Math.sin(E); + y = p * Math.cos(E) - c1; + } else { + x *= Math.cos(y); + y *= -1; + } + return [ + scale * x + translate[0], + scale * y + translate[1] + ]; + } + + bonne.invert = function(coordinates) { + var x = (coordinates[0] - translate[0]) / scale, + y = (coordinates[1] - translate[1]) / scale; + if (y1) { + var c = c1 + y, p = Math.sqrt(x * x + c * c); + y = c1 + y1 - p; + x = x0 + p * Math.atan2(x, c) / Math.cos(y); + } else { + y *= -1; + x /= Math.cos(y); + } + return [ + x / d3_geo_radians, + y / d3_geo_radians + ]; + }; + + // 90° for Werner, 0° for Sinusoidal + bonne.parallel = function(x) { + if (!arguments.length) return y1 / d3_geo_radians; + c1 = 1 / Math.tan(y1 = x * d3_geo_radians); + return bonne; + }; + + bonne.origin = function(x) { + if (!arguments.length) return [x0 / d3_geo_radians, y0 / d3_geo_radians]; + x0 = x[0] * d3_geo_radians; + y0 = x[1] * d3_geo_radians; + return bonne; + }; + + bonne.scale = function(x) { + if (!arguments.length) return scale; + scale = +x; + return bonne; + }; + + bonne.translate = function(x) { + if (!arguments.length) return translate; + translate = [+x[0], +x[1]]; + return bonne; + }; + + return bonne.origin([0, 0]).parallel(45); +};