add support for UTM and Traverse Mercator projection (#2108)

* add support for UTM and Traverse Mercator projection

* fix specs

* fix specs

* fix specs

src/geo/projection/Projection.EPSG4326.js

@@ -21,6 +21,7 @@ export default extend({}, Common, /** @lends projection.EPSG4326 */ {
      * @constant
      */
     code: 'EPSG:4326',
+    aliases: ['EPSG:4490'],
     project: function (p, out) {
         if (out) {
             out.x = p.x;

src/geo/projection/Projection.EPSG9807.js

@@ -0,0 +1,89 @@
+import { isNil, extend } from '../../core/util';
+import Common from './Projection';
+import Coordinate from '../Coordinate';
+import { WGS84Sphere } from '../measurer';
+import etmerc from './etmerc.js';
+
+// from proj_api.h
+const RAD_TO_DEG = 57.295779513082321,
+    DEG_TO_RAD = 0.017453292519943296;
+
+// from pj_transform.c
+const SRS_WGS84_SEMIMAJOR = 6378137;
+const SRS_WGS84_ESQUARED = 0.0066943799901413165;
+
+/**
+ * Traverse Mercator Projection
+ *
+ * @class
+ * @category geo
+ * @protected
+ * @memberOf projection
+ * @name EPSG9807
+ * @mixes projection.Common
+ * @mixes measurer.WGS84Sphere
+ */
+export default {
+    code: 'EPSG:9807',
+    aliases: ['Traverse_Mercator'],
+    create(params) {
+        const P = {
+            a: SRS_WGS84_SEMIMAJOR,
+            es: SRS_WGS84_ESQUARED,
+            x0: isNil(params.falseEasting) ? 500000 : params.falseEasting,
+            y0: isNil(params.falseNorthing) ? 0 : params.falseNorthing,
+            k0: params.scaleFactor || 0.9996,
+            lam0: (params.centralMeridian || 0) * DEG_TO_RAD,
+            phi0: (params.latitudeOfOrigin || 0) * DEG_TO_RAD,
+            originLam0: params.startLongtitude || 0,
+            originPhi0: params.startLatitude || 0
+        };
+        etmerc(P);
+        const lp = { lam: 0, phi: 0 };
+        const xy = {};
+        let originX = 0;
+        let originY = 0;
+        if (P.originLam0 || P.originPhi0) {
+            lp.lam = P.originLam0 * DEG_TO_RAD - P.lam0;
+            lp.phi = P.originPhi0 * DEG_TO_RAD;
+            P.fwd(lp, xy);
+            originX = P.a * xy.x + P.x0;
+            originY = P.a * xy.y + P.y0;
+        }
+
+        return extend({}, Common, {
+            /**
+             * "EPSG:9807", Code of the projection
+             * @type {String}
+             * @constant
+             */
+            code: 'EPSG:9807',
+            project: function (p, out) {
+                lp.lam = p.x * DEG_TO_RAD - P.lam0;
+                lp.phi = p.y * DEG_TO_RAD;
+                P.fwd(lp, xy);
+                const x = P.a * xy.x + P.x0 - originX;
+                const y = P.a * xy.y + P.y0 - originY;
+                if (out) {
+                    out.x = x;
+                    out.y = y;
+                    return out;
+                }
+                return new Coordinate(x, y);
+            },
+            unproject: function (p, out) {
+                xy.x = (p.x - P.x0 + originX) / P.a;
+                xy.y = (p.y - P.y0 + originY) / P.a;
+                P.inv(xy, lp);
+                const x = (lp.lam + P.lam0) * RAD_TO_DEG;
+                const y = lp.phi * RAD_TO_DEG;
+                if (out) {
+                    out.x = x;
+                    out.y = y;
+                    return out;
+                }
+                return new Coordinate(x, y);
+            }
+        }, WGS84Sphere);
+    }
+};

src/geo/projection/Projection.UTM.js

@@ -0,0 +1,37 @@
+import { extend } from '../../core/util';
+import PROJ9807 from './Projection.EPSG9807';
+
+/**
+ * Universal Traverse Mercator projection
+ *
+ * @class
+ * @category geo
+ * @protected
+ * @memberOf projection
+ * @name EPSG4490
+ * @mixes projection.EPSG4326
+ * @mixes measurer.WGS84Sphere
+ */
+export default extend({}, PROJ9807, /** @lends projection.EPSG4490 */ {
+    /**
+     * "EPSG:4490", Code of the projection
+     * @type {String}
+     * @constant
+     */
+    code: 'utm',
+    aliases: [],
+    create(params) {
+        const P = {};
+        let zone = parseInt(params.zone);
+        P.falseNorthing = params.south ? 10000000 : 0;
+        P.falseEasting = 500000;
+        if (zone > 0 && zone <= 60) {
+            zone--;
+        } else {
+            throw new Error('zone must be > 0 and <= 60.');
+        }
+        P.centralMeridian = (zone + 0.5) * 6 - 180;
+        P.scaleFactor = 0.9996;
+        return PROJ9807.create(P);
+    }
+});