leaflet平面无投影坐标系的扩展

songyumeng · songyumeng · commit 5ee67cd8b97f · 2017-02-23T10:15:57.000+08:00
diff --git a/src/Leaflet/NonEarthCRS.js b/src/Leaflet/NonEarthCRS.js
@@ -0,0 +1,72 @@
+L.Projection = {};
+
+NonProjection = L.Class.extend({
+    initialize: function (bounds) {
+        this.b = bounds;
+    },
+    project: function (latlng) {
+        return new L.Point(latlng.lng, latlng.lat);
+    },
+
+    unproject: function (point) {
+        return new L.LatLng(point.y, point.x);
+    },
+
+    bounds: this.b
+});
+L.supermap.NonProjection = function (bounds) {
+    return new NonProjection(bounds)
+}
+module.exports = L.supermap.NonProjection;
+NonEarthCRS = L.Class.extend({
+    includes: L.CRS,
+
+    initialize: function (options) {
+        if (options.origin) {
+            this.transformation =
+                new L.Transformation(1, options.origin.x,
+                    -1, options.origin.y);
+        }
+        this.projection = L.supermap.NonProjection(options.bounds);
+        this.bounds = options.bounds;
+        this.origin = options.origin;
+        this.resolutions = options.resolutions;
+    },
+
+    scale: function (zoom) {
+        if (!this.resolutions || this.resolutions.length === 0) {
+            var width = Math.max(this.bounds.getSize().x, this.bounds.getSize().y);
+            var defaultScale = 1 / (width / 256);
+            return defaultScale * Math.pow(2, zoom);
+        }
+        return 1 / this.resolutions[zoom];
+    },
+
+    zoom: function (scale) {
+        if (!this.resolutions || this.resolutions.length === 0) {
+            var width = Math.max(this.bounds.getSize().x, this.bounds.getSize().y);
+            var defaultScale = 1 / (width / 256);
+            return scale / defaultScale;
+        }
+        for (var i = 0; i < this.resolutions.length; i++) {
+            if (1 / this.resolutions == scale) {
+                return i
+            }
+        }
+        return -1;
+    },
+
+    distance: function (latlng1, latlng2) {
+        var dx = latlng2.lng - latlng1.lng,
+            dy = latlng2.lat - latlng1.lat;
+
+        return Math.sqrt(dx * dx + dy * dy);
+    },
+
+    infinite: true
+});
+L.supermap = L.supermap || {};
+L.supermap.NonEarthCRS = function (options) {
+    return new NonEarthCRS(options)
+}
+module.exports = L.supermap.NonEarthCRS;
diff --git a/src/Leaflet/base.js b/src/Leaflet/base.js
@@ -4,8 +4,8 @@
  * 2、提供必要的转换工具
  */
 require('../Core/format/GeoJSON');
+require('./NonEarthCRS');
 L.supermap = L.supermap || {};
-
 L.Util.toSuperMapGeometry = function (geometry) {
     if (!geometry) {
         return geometry;
