first commit

2023-05-19 00:42:48 +08:00
commit 53de9c6c51
243 changed files with 39485 additions and 0 deletions
@@ -0,0 +1,151 @@
+'use strict';
+
+  function Point(x, y) {
+      this.x = x;
+      this.y = y;
+  }
+
+  /** return a copy of this point with coordinates as int */
+  Point.prototype.floor = function() {
+      return new Point(this.x>>0, this.y>>0);
+  }
+
+  function LatLng(lat, lng) {
+      this.lat = lat;
+      this.lng = lng;
+  }
+
+  LatLng.prototype.clone = function() {
+      return new LatLng(this.lat, this.lng);
+  }
+
+  var TILE_SIZE = 256;
+
+  MercatorProjection.prototype.TILE_SIZE = TILE_SIZE;
+
+  function bound(value, opt_min, opt_max) {
+    if (opt_min != null) value = Math.max(value, opt_min);
+    if (opt_max != null) value = Math.min(value, opt_max);
+    return value;
+  }
+
+  function degreesToRadians(deg) {
+    return deg * (Math.PI / 180);
+  }
+
+  function radiansToDegrees(rad) {
+    return rad / (Math.PI / 180);
+  }
+
+  function MercatorProjection() {
+    this.pixelOrigin_ = new Point(TILE_SIZE / 2,
+        TILE_SIZE / 2);
+    this.pixelsPerLonDegree_ = TILE_SIZE / 360;
+    this.pixelsPerLonRadian_ = TILE_SIZE / (2 * Math.PI);
+  }
+
+  MercatorProjection.prototype.fromLatLngToPixel = function(latLng, zoom) {
+      var p = this.fromLatLngToPoint(latLng);
+      return this.toPixelCoordinate(p, zoom);
+  };
+
+  MercatorProjection.prototype.fromLatLngToPoint = function(latLng,
+      opt_point) {
+    var me = this;
+    var point = opt_point || new Point(0, 0);
+    var origin = me.pixelOrigin_;
+
+    point.x = origin.x + latLng.lng * me.pixelsPerLonDegree_;
+
+    // NOTE(appleton): Truncating to 0.9999 effectively limits latitude to
+    // 89.189.  This is about a third of a tile past the edge of the world
+    // tile.
+    var siny = bound(Math.sin(degreesToRadians(latLng.lat)), -0.9999,
+        0.9999);
+    point.y = origin.y + 0.5 * Math.log((1 + siny) / (1 - siny)) *
+        -me.pixelsPerLonRadian_;
+    return point;
+  };
+
+  MercatorProjection.prototype.fromPointToLatLng = function(point) {
+    var me = this;
+    var origin = me.pixelOrigin_;
+    var lng = (point.x - origin.x) / me.pixelsPerLonDegree_;
+    var latRadians = (point.y - origin.y) / -me.pixelsPerLonRadian_;
+    var lat = radiansToDegrees(2 * Math.atan(Math.exp(latRadians)) -
+        Math.PI / 2);
+    return new LatLng(lat, lng);
+  };
+
+  MercatorProjection.prototype.tileBBox = function(x, y, zoom) {
+    var numTiles = 1 << zoom;
+    var inc = TILE_SIZE/numTiles;
+    var px = x*TILE_SIZE/numTiles;
+    var py = y*TILE_SIZE/numTiles;
+    return [
+        this.fromPointToLatLng(new Point(px, py + inc)),
+        this.fromPointToLatLng(new Point(px + inc, py))
+    ];
+  };
+
+  MercatorProjection.prototype.tilePoint = function(x, y, zoom) {
+        var numTiles = 1 << zoom;
+        var px = x*TILE_SIZE;
+        var py = y*TILE_SIZE;
+        return [px, py];
+  }
+  MercatorProjection.prototype.fromPixelToLatLng = function(pixel, zoom) {
+        var numTiles = 1 << zoom;
+        var p = new Point(
+                pixel.x/numTiles,
+                pixel.y/numTiles);
+        return this.fromPointToLatLng(p);
+
+
+  }
+
+  MercatorProjection.prototype.toPixelCoordinate = function(worldCoordinate, zoom) {
+        var numTiles = 1 << zoom;
+        return new Point(
+                worldCoordinate.x * numTiles,
+                worldCoordinate.y * numTiles);
+  }
+
+  MercatorProjection.prototype.latLngToTilePoint = function(latLng, x, y, zoom) {
+        var numTiles = 1 << zoom;
+        var projection = this;
+        var worldCoordinate = projection.fromLatLngToPoint(latLng);
+        var pixelCoordinate = new Point(
+                worldCoordinate.x * numTiles,
+                worldCoordinate.y * numTiles);
+        var tp = this.tilePoint(x, y, zoom);
+        return new Point(
+                Math.floor(pixelCoordinate.x - tp[0]),
+                Math.floor(pixelCoordinate.y - tp[1]));
+  }
+
+  MercatorProjection.prototype.pixelToTile = function(pixelCoordinate) {
+        return new Point(
+                Math.floor(pixelCoordinate.x / TILE_SIZE),
+                Math.floor(pixelCoordinate.y / TILE_SIZE));
+  };
+
+  MercatorProjection.prototype.pointToTile = function(point, zoom) {
+        var numTiles = 1 << zoom;
+        var pixelCoordinate = new Point(
+                point.x * numTiles,
+                point.y * numTiles);
+        return this.pixelToTile(pixelCoordinate);
+  };
+
+  MercatorProjection.prototype.latLngToTile = function(latLng, zoom) {
+        var numTiles = 1 << zoom;
+        var projection = this;
+        var worldCoordinate = projection.fromLatLngToPoint(latLng);
+        var pixelCoordinate = new Point(
+                worldCoordinate.x * numTiles,
+                worldCoordinate.y * numTiles);
+        return new Point(
+                Math.floor(pixelCoordinate.x / TILE_SIZE),
+                Math.floor(pixelCoordinate.y / TILE_SIZE));
+  }