How to enable horizontally world repeat in google maps?

问题

I am using Google maps (via OpenStreetMap) and need to have world repeated horizontally. I thought its by default, but it is not.

var map;

map = new google.maps.Map(element, {
    center : new google.maps.LatLng(mapa_start_X, mapa_start_Y),
    zoom : mapa_start_Z,
    mapTypeId: "OSM",
    mapTypeControl: false,
    streetViewControl: true
});

map.mapTypes.set("OSM", new google.maps.ImageMapType({
    getTileUrl: function(coord, zoom) {
        return "http://tile.openstreetmap.org/" + zoom + "/" + coord.x + "/" + coord.y + ".png";
        //return "/tile.php?z=" + zoom + "&x=" + coord.x + "&y=" + coord.y;
    },
    tileSize: new google.maps.Size(256, 256),
    name: "OpenStreetMap",
    maxZoom: 18
}));

element is object in DOM, mapa_start_X, mapa_start_Y and mapa_start_Z are variables defined in other part of code.

What should I add to the constructor of the map?

DEMO

回答1:

You have to change the getTileUrl function to normalize the coordinates in the x direction like the example in the documentation.

map.mapTypes.set("OSM", new google.maps.ImageMapType({
    getTileUrl: function (coord, zoom) {
        var normalizedCoord = getNormalizedCoord(coord, zoom);
        if (!normalizedCoord) {
            return null;
        }
        return "http://tile.openstreetmap.org/" + zoom + "/" + normalizedCoord.x + "/" + normalizedCoord.y + ".png";
    },
    tileSize: new google.maps.Size(256, 256),
    name: "OpenStreetMap",
    maxZoom: 18,
    minZoom: 1
}));

// Normalizes the coords that tiles repeat across the x axis (horizontally)
// like the standard Google map tiles.
function getNormalizedCoord(coord, zoom) {
  var y = coord.y;
  var x = coord.x;

  // tile range in one direction range is dependent on zoom level
  // 0 = 1 tile, 1 = 2 tiles, 2 = 4 tiles, 3 = 8 tiles, etc
  var tileRange = 1 << zoom;

  // don't repeat across y-axis (vertically)
  if (y < 0 || y >= tileRange) {
    return null;
  }

  // repeat across x-axis
  if (x < 0 || x >= tileRange) {
    x = (x % tileRange + tileRange) % tileRange;
  }

  return {
    x: x,
    y: y
  };
}

working fiddle

来源：https://stackoverflow.com/questions/28947413/how-to-enable-horizontally-world-repeat-in-google-maps

标签

google-maps

openstreetmap