Function project

external/.d3.js:12405–12408

(x, y)

  var c = 1 + sy0 * (2 * n - sy0), r0 = sqrt$2(c) / n;

  function project(x, y) {
    var r = sqrt$2(c - 2 * n * sin$1(y)) / n;
    return [r * sin$1(x *= n), r0 - r * cos$1(x)];
  }

  project.invert = function(x, y) {
    var r0y = r0 - y,