Map in a cube

index.js

@@ -63,6 +63,7 @@ export {default as geoPolyconic, polyconicRaw as geoPolyconicRaw} from "./src/po
 export {default as geoPolyhedral} from "./src/polyhedral/index.js";
 export {default as geoPolyhedralButterfly} from "./src/polyhedral/butterfly.js";
 export {default as geoPolyhedralCollignon} from "./src/polyhedral/collignon.js";
+export {default as geoPolyhedralReichard} from "./src/polyhedral/reichard.js";
 export {default as geoPolyhedralWaterman} from "./src/polyhedral/waterman.js";
 export {default as geoProject} from "./src/project/index";
 export {default as geoGringortenQuincuncial} from "./src/quincuncial/gringorten.js";

src/polyhedral/reichard.js

@@ -0,0 +1,33 @@
+import {geoCentroid as centroid, geoGnomonic as gnomonic} from "d3-geo";
+import {pi, atan, sqrt1_2, degrees} from "../math";
+import polyhedral from "./index";
+import cube from "./cube";
+
+var phi1 = atan(sqrt1_2);
+
+export default function (faceProjection) {
+  faceProjection = faceProjection || function (face) {
+    var c = centroid({type: 'MultiPoint', coordinates: face});
+    return gnomonic().scale(1).translate([0, 0]).rotate([-c[0], -c[1]]);
+  };
+
+  var faces = cube.map(function (face) {
+    return {face: face, project: faceProjection(face)};
+  });
+
+  [-1, 4, 5, 2, 0, 1].forEach(function (d, i) {
+    var node = faces[d];
+    node && (node.children || (node.children = [])).push(faces[i]);
+  });
+
+  return polyhedral(faces[0], function (lambda, phi) {
+    return faces[
+      phi >= phi1 ? 0 : phi <= -phi1 ? 5 :
+      lambda <= -pi / 2 ? 3 :
+      lambda <=       0 ? 4 :
+      lambda <=  pi / 2 ? 1 : 2
+    ];
+  })
+    .scale(63.4368)
+    .center([45, -45]);
+}

test/render-world

@@ -50,6 +50,7 @@ switch (projectionName) {
   case "modifiedStereographicGs50":
   case "modifiedStereographicMiller":
   case "polyhedralButterfly":
+  case "polyhedralReichard":
   case "polyhedralWaterman":
   case "polyhedralCollignon": {
     context.beginPath();