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Created February 22, 2013 19:17
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<!DOCTYPE html>
<html>
<head>
<script src='modestmaps.js'></script>
<style>
body { margin:0; padding:0; }
#map {
position: absolute;
top: 0;
left: 0;
right: 0;
bottom: 0;
}
</style>
</head>
<body>
<div id='map'></div>
<script>
var map = new MM.Map('map');
map.addLayer(MM.TemplatedLayer('http://a.tiles.mapbox.com/v3/tmcw.map-5hafkxww/{Z}/{X}/{Y}.png'));
map.zoom(11).center({ lat: 38.904, lon: -77.008 });
</script>
</body>
</html>
/*!
* Modest Maps JS v3.3.6
* http://modestmaps.com/
*
* Copyright (c) 2011 Stamen Design, All Rights Reserved.
*
* Open source under the BSD License.
* http://creativecommons.org/licenses/BSD/
*
* Versioned using Semantic Versioning (v.major.minor.patch)
* See CHANGELOG and http://semver.org/ for more details.
*
*/
var previousMM = MM;
// namespacing for backwards-compatibility
if (!com) {
var com = {};
if (!com.modestmaps) com.modestmaps = {};
}
var MM = com.modestmaps = {
noConflict: function() {
MM = previousMM;
return this;
}
};
(function(MM) {
// Make inheritance bearable: clone one level of properties
MM.extend = function(child, parent) {
for (var property in parent.prototype) {
if (typeof child.prototype[property] == "undefined") {
child.prototype[property] = parent.prototype[property];
}
}
return child;
};
MM.getFrame = function () {
// native animation frames
// http://webstuff.nfshost.com/anim-timing/Overview.html
// http://dev.chromium.org/developers/design-documents/requestanimationframe-implementation
// http://paulirish.com/2011/requestanimationframe-for-smart-animating/
// can't apply these directly to MM because Chrome needs window
// to own webkitRequestAnimationFrame (for example)
// perhaps we should namespace an alias onto window instead?
// e.g. window.mmRequestAnimationFrame?
return function(callback) {
(window.requestAnimationFrame ||
window.webkitRequestAnimationFrame ||
window.mozRequestAnimationFrame ||
window.oRequestAnimationFrame ||
window.msRequestAnimationFrame ||
function (callback) {
window.setTimeout(function () {
callback(+new Date());
}, 10);
})(callback);
};
}();
// Inspired by LeafletJS
MM.transformProperty = (function(props) {
if (!this.document) return; // node.js safety
var style = document.documentElement.style;
for (var i = 0; i < props.length; i++) {
if (props[i] in style) {
return props[i];
}
}
return false;
})(['transform', 'WebkitTransform', 'OTransform', 'MozTransform', 'msTransform']);
MM.matrixString = function(point) {
// Make the result of point.scale * point.width a whole number.
if (point.scale * point.width % 1) {
point.scale += (1 - point.scale * point.width % 1) / point.width;
}
var scale = point.scale || 1;
if (MM._browser.webkit3d) {
return 'translate3d(' +
point.x.toFixed(0) + 'px,' + point.y.toFixed(0) + 'px, 0px)' +
'scale3d(' + scale + ',' + scale + ', 1)';
} else {
return 'translate(' +
point.x.toFixed(6) + 'px,' + point.y.toFixed(6) + 'px)' +
'scale(' + scale + ',' + scale + ')';
}
};
MM._browser = (function(window) {
return {
webkit: ('WebKitCSSMatrix' in window),
webkit3d: ('WebKitCSSMatrix' in window) && ('m11' in new WebKitCSSMatrix())
};
})(this); // use this for node.js global
MM.moveElement = function(el, point) {
if (MM.transformProperty) {
// Optimize for identity transforms, where you don't actually
// need to change this element's string. Browsers can optimize for
// the .style.left case but not for this CSS case.
if (!point.scale) point.scale = 1;
if (!point.width) point.width = 0;
if (!point.height) point.height = 0;
var ms = MM.matrixString(point);
if (el[MM.transformProperty] !== ms) {
el.style[MM.transformProperty] =
el[MM.transformProperty] = ms;
}
} else {
el.style.left = point.x + 'px';
el.style.top = point.y + 'px';
// Don't set width unless asked to: this is performance-intensive
// and not always necessary
if (point.width && point.height && point.scale) {
el.style.width = Math.ceil(point.width * point.scale) + 'px';
el.style.height = Math.ceil(point.height * point.scale) + 'px';
}
}
};
// Events
// Cancel an event: prevent it from bubbling
MM.cancelEvent = function(e) {
// there's more than one way to skin this cat
e.cancelBubble = true;
e.cancel = true;
e.returnValue = false;
if (e.stopPropagation) { e.stopPropagation(); }
if (e.preventDefault) { e.preventDefault(); }
return false;
};
MM.coerceLayer = function(layerish) {
if (typeof layerish == 'string') {
// Probably a template string
return new MM.Layer(new MM.TemplatedLayer(layerish));
} else if ('draw' in layerish && typeof layerish.draw == 'function') {
// good enough, though we should probably enforce .parent and .destroy() too
return layerish;
} else {
// probably a MapProvider
return new MM.Layer(layerish);
}
};
// see http://ejohn.org/apps/jselect/event.html for the originals
MM.addEvent = function(obj, type, fn) {
if (obj.addEventListener) {
obj.addEventListener(type, fn, false);
if (type == 'mousewheel') {
obj.addEventListener('DOMMouseScroll', fn, false);
}
} else if (obj.attachEvent) {
obj['e'+type+fn] = fn;
obj[type+fn] = function(){ obj['e'+type+fn](window.event); };
obj.attachEvent('on'+type, obj[type+fn]);
}
};
MM.removeEvent = function( obj, type, fn ) {
if (obj.removeEventListener) {
obj.removeEventListener(type, fn, false);
if (type == 'mousewheel') {
obj.removeEventListener('DOMMouseScroll', fn, false);
}
} else if (obj.detachEvent) {
obj.detachEvent('on'+type, obj[type+fn]);
obj[type+fn] = null;
}
};
// Cross-browser function to get current element style property
MM.getStyle = function(el,styleProp) {
if (el.currentStyle)
return el.currentStyle[styleProp];
else if (window.getComputedStyle)
return document.defaultView.getComputedStyle(el,null).getPropertyValue(styleProp);
};
// Point
MM.Point = function(x, y) {
this.x = parseFloat(x);
this.y = parseFloat(y);
};
MM.Point.prototype = {
x: 0,
y: 0,
toString: function() {
return "(" + this.x.toFixed(3) + ", " + this.y.toFixed(3) + ")";
},
copy: function() {
return new MM.Point(this.x, this.y);
}
};
// Get the euclidean distance between two points
MM.Point.distance = function(p1, p2) {
return Math.sqrt(
Math.pow(p2.x - p1.x, 2) +
Math.pow(p2.y - p1.y, 2));
};
// Get a point between two other points, biased by `t`.
MM.Point.interpolate = function(p1, p2, t) {
return new MM.Point(
p1.x + (p2.x - p1.x) * t,
p1.y + (p2.y - p1.y) * t);
};
// Coordinate
// ----------
// An object representing a tile position, at as specified zoom level.
// This is not necessarily a precise tile - `row`, `column`, and
// `zoom` can be floating-point numbers, and the `container()` function
// can be used to find the actual tile that contains the point.
MM.Coordinate = function(row, column, zoom) {
this.row = row;
this.column = column;
this.zoom = zoom;
};
MM.Coordinate.prototype = {
row: 0,
column: 0,
zoom: 0,
toString: function() {
return "(" + this.row.toFixed(3) +
", " + this.column.toFixed(3) +
" @" + this.zoom.toFixed(3) + ")";
},
// Quickly generate a string representation of this coordinate to
// index it in hashes.
toKey: function() {
// We've tried to use efficient hash functions here before but we took
// them out. Contributions welcome but watch out for collisions when the
// row or column are negative and check thoroughly (exhaustively) before
// committing.
return this.zoom + ',' + this.row + ',' + this.column;
},
// Clone this object.
copy: function() {
return new MM.Coordinate(this.row, this.column, this.zoom);
},
// Get the actual, rounded-number tile that contains this point.
container: function() {
// using floor here (not parseInt, ~~) because we want -0.56 --> -1
return new MM.Coordinate(Math.floor(this.row),
Math.floor(this.column),
Math.floor(this.zoom));
},
// Recalculate this Coordinate at a different zoom level and return the
// new object.
zoomTo: function(destination) {
var power = Math.pow(2, destination - this.zoom);
return new MM.Coordinate(this.row * power,
this.column * power,
destination);
},
// Recalculate this Coordinate at a different relative zoom level and return the
// new object.
zoomBy: function(distance) {
var power = Math.pow(2, distance);
return new MM.Coordinate(this.row * power,
this.column * power,
this.zoom + distance);
},
// Move this coordinate up by `dist` coordinates
up: function(dist) {
if (dist === undefined) dist = 1;
return new MM.Coordinate(this.row - dist, this.column, this.zoom);
},
// Move this coordinate right by `dist` coordinates
right: function(dist) {
if (dist === undefined) dist = 1;
return new MM.Coordinate(this.row, this.column + dist, this.zoom);
},
// Move this coordinate down by `dist` coordinates
down: function(dist) {
if (dist === undefined) dist = 1;
return new MM.Coordinate(this.row + dist, this.column, this.zoom);
},
// Move this coordinate left by `dist` coordinates
left: function(dist) {
if (dist === undefined) dist = 1;
return new MM.Coordinate(this.row, this.column - dist, this.zoom);
}
};
// Location
// --------
MM.Location = function(lat, lon) {
this.lat = parseFloat(lat);
this.lon = parseFloat(lon);
};
MM.Location.prototype = {
lat: 0,
lon: 0,
toString: function() {
return "(" + this.lat.toFixed(3) + ", " + this.lon.toFixed(3) + ")";
},
copy: function() {
return new MM.Location(this.lat, this.lon);
}
};
// returns approximate distance between start and end locations
//
// default unit is meters
//
// you can specify different units by optionally providing the
// earth's radius in the units you desire
//
// Default is 6,378,000 metres, suggested values are:
//
// * 3963.1 statute miles
// * 3443.9 nautical miles
// * 6378 km
//
// see [Formula and code for calculating distance based on two lat/lon locations](http://jan.ucc.nau.edu/~cvm/latlon_formula.html)
MM.Location.distance = function(l1, l2, r) {
if (!r) {
// default to meters
r = 6378000;
}
var deg2rad = Math.PI / 180.0,
a1 = l1.lat * deg2rad,
b1 = l1.lon * deg2rad,
a2 = l2.lat * deg2rad,
b2 = l2.lon * deg2rad,
c = Math.cos(a1) * Math.cos(b1) * Math.cos(a2) * Math.cos(b2),
d = Math.cos(a1) * Math.sin(b1) * Math.cos(a2) * Math.sin(b2),
e = Math.sin(a1) * Math.sin(a2);
return Math.acos(c + d + e) * r;
};
// Interpolates along a great circle, f between 0 and 1
//
// * FIXME: could be heavily optimized (lots of trig calls to cache)
// * FIXME: could be inmproved for calculating a full path
MM.Location.interpolate = function(l1, l2, f) {
if (l1.lat === l2.lat && l1.lon === l2.lon) {
return new MM.Location(l1.lat, l1.lon);
}
var deg2rad = Math.PI / 180.0,
lat1 = l1.lat * deg2rad,
lon1 = l1.lon * deg2rad,
lat2 = l2.lat * deg2rad,
lon2 = l2.lon * deg2rad;
var d = 2 * Math.asin(
Math.sqrt(
Math.pow(Math.sin((lat1 - lat2) / 2), 2) +
Math.cos(lat1) * Math.cos(lat2) *
Math.pow(Math.sin((lon1 - lon2) / 2), 2)));
var A = Math.sin((1-f)*d)/Math.sin(d);
var B = Math.sin(f*d)/Math.sin(d);
var x = A * Math.cos(lat1) * Math.cos(lon1) +
B * Math.cos(lat2) * Math.cos(lon2);
var y = A * Math.cos(lat1) * Math.sin(lon1) +
B * Math.cos(lat2) * Math.sin(lon2);
var z = A * Math.sin(lat1) + B * Math.sin(lat2);
var latN = Math.atan2(z, Math.sqrt(Math.pow(x, 2) + Math.pow(y, 2)));
var lonN = Math.atan2(y,x);
return new MM.Location(latN / deg2rad, lonN / deg2rad);
};
// Returns bearing from one point to another
//
// * FIXME: bearing is not constant along significant great circle arcs.
MM.Location.bearing = function(l1, l2) {
var deg2rad = Math.PI / 180.0,
lat1 = l1.lat * deg2rad,
lon1 = l1.lon * deg2rad,
lat2 = l2.lat * deg2rad,
lon2 = l2.lon * deg2rad;
var result = Math.atan2(
Math.sin(lon1 - lon2) *
Math.cos(lat2),
Math.cos(lat1) *
Math.sin(lat2) -
Math.sin(lat1) *
Math.cos(lat2) *
Math.cos(lon1 - lon2)
) / -(Math.PI / 180);
// map it into 0-360 range
return (result < 0) ? result + 360 : result;
};
// Extent
// ----------
// An object representing a map's rectangular extent, defined by its north,
// south, east and west bounds.
MM.Extent = function(north, west, south, east) {
if (north instanceof MM.Location &&
west instanceof MM.Location) {
var northwest = north,
southeast = west;
north = northwest.lat;
west = northwest.lon;
south = southeast.lat;
east = southeast.lon;
}
if (isNaN(south)) south = north;
if (isNaN(east)) east = west;
this.north = Math.max(north, south);
this.south = Math.min(north, south);
this.east = Math.max(east, west);
this.west = Math.min(east, west);
};
MM.Extent.prototype = {
// boundary attributes
north: 0,
south: 0,
east: 0,
west: 0,
copy: function() {
return new MM.Extent(this.north, this.west, this.south, this.east);
},
toString: function(precision) {
if (isNaN(precision)) precision = 3;
return [
this.north.toFixed(precision),
this.west.toFixed(precision),
this.south.toFixed(precision),
this.east.toFixed(precision)
].join(", ");
},
// getters for the corner locations
northWest: function() {
return new MM.Location(this.north, this.west);
},
southEast: function() {
return new MM.Location(this.south, this.east);
},
northEast: function() {
return new MM.Location(this.north, this.east);
},
southWest: function() {
return new MM.Location(this.south, this.west);
},
// getter for the center location
center: function() {
return new MM.Location(
this.south + (this.north - this.south) / 2,
this.east + (this.west - this.east) / 2
);
},
// extend the bounds to include a location's latitude and longitude
encloseLocation: function(loc) {
if (loc.lat > this.north) this.north = loc.lat;
if (loc.lat < this.south) this.south = loc.lat;
if (loc.lon > this.east) this.east = loc.lon;
if (loc.lon < this.west) this.west = loc.lon;
},
// extend the bounds to include multiple locations
encloseLocations: function(locations) {
var len = locations.length;
for (var i = 0; i < len; i++) {
this.encloseLocation(locations[i]);
}
},
// reset bounds from a list of locations
setFromLocations: function(locations) {
var len = locations.length,
first = locations[0];
this.north = this.south = first.lat;
this.east = this.west = first.lon;
for (var i = 1; i < len; i++) {
this.encloseLocation(locations[i]);
}
},
// extend the bounds to include another extent
encloseExtent: function(extent) {
if (extent.north > this.north) this.north = extent.north;
if (extent.south < this.south) this.south = extent.south;
if (extent.east > this.east) this.east = extent.east;
if (extent.west < this.west) this.west = extent.west;
},
// determine if a location is within this extent
containsLocation: function(loc) {
return loc.lat >= this.south &&
loc.lat <= this.north &&
loc.lon >= this.west &&
loc.lon <= this.east;
},
// turn an extent into an array of locations containing its northwest
// and southeast corners (used in MM.Map.setExtent())
toArray: function() {
return [this.northWest(), this.southEast()];
}
};
MM.Extent.fromString = function(str) {
var parts = str.split(/\s*,\s*/);
if (parts.length != 4) {
throw "Invalid extent string (expecting 4 comma-separated numbers)";
}
return new MM.Extent(
parseFloat(parts[0]),
parseFloat(parts[1]),
parseFloat(parts[2]),
parseFloat(parts[3])
);
};
MM.Extent.fromArray = function(locations) {
var extent = new MM.Extent();
extent.setFromLocations(locations);
return extent;
};
// Transformation
// --------------
MM.Transformation = function(ax, bx, cx, ay, by, cy) {
this.ax = ax;
this.bx = bx;
this.cx = cx;
this.ay = ay;
this.by = by;
this.cy = cy;
};
MM.Transformation.prototype = {
ax: 0,
bx: 0,
cx: 0,
ay: 0,
by: 0,
cy: 0,
transform: function(point) {
return new MM.Point(this.ax * point.x + this.bx * point.y + this.cx,
this.ay * point.x + this.by * point.y + this.cy);
},
untransform: function(point) {
return new MM.Point((point.x * this.by - point.y * this.bx -
this.cx * this.by + this.cy * this.bx) /
(this.ax * this.by - this.ay * this.bx),
(point.x * this.ay - point.y * this.ax -
this.cx * this.ay + this.cy * this.ax) /
(this.bx * this.ay - this.by * this.ax));
}
};
// Generates a transform based on three pairs of points,
// a1 -> a2, b1 -> b2, c1 -> c2.
MM.deriveTransformation = function(a1x, a1y, a2x, a2y,
b1x, b1y, b2x, b2y,
c1x, c1y, c2x, c2y) {
var x = MM.linearSolution(a1x, a1y, a2x,
b1x, b1y, b2x,
c1x, c1y, c2x);
var y = MM.linearSolution(a1x, a1y, a2y,
b1x, b1y, b2y,
c1x, c1y, c2y);
return new MM.Transformation(x[0], x[1], x[2], y[0], y[1], y[2]);
};
// Solves a system of linear equations.
//
// t1 = (a * r1) + (b + s1) + c
// t2 = (a * r2) + (b + s2) + c
// t3 = (a * r3) + (b + s3) + c
//
// r1 - t3 are the known values.
// a, b, c are the unknowns to be solved.
// returns the a, b, c coefficients.
MM.linearSolution = function(r1, s1, t1, r2, s2, t2, r3, s3, t3) {
// make them all floats
r1 = parseFloat(r1);
s1 = parseFloat(s1);
t1 = parseFloat(t1);
r2 = parseFloat(r2);
s2 = parseFloat(s2);
t2 = parseFloat(t2);
r3 = parseFloat(r3);
s3 = parseFloat(s3);
t3 = parseFloat(t3);
var a = (((t2 - t3) * (s1 - s2)) - ((t1 - t2) * (s2 - s3))) /
(((r2 - r3) * (s1 - s2)) - ((r1 - r2) * (s2 - s3)));
var b = (((t2 - t3) * (r1 - r2)) - ((t1 - t2) * (r2 - r3))) /
(((s2 - s3) * (r1 - r2)) - ((s1 - s2) * (r2 - r3)));
var c = t1 - (r1 * a) - (s1 * b);
return [ a, b, c ];
};
// Projection
// ----------
// An abstract class / interface for projections
MM.Projection = function(zoom, transformation) {
if (!transformation) {
transformation = new MM.Transformation(1, 0, 0, 0, 1, 0);
}
this.zoom = zoom;
this.transformation = transformation;
};
MM.Projection.prototype = {
zoom: 0,
transformation: null,
rawProject: function(point) {
throw "Abstract method not implemented by subclass.";
},
rawUnproject: function(point) {
throw "Abstract method not implemented by subclass.";
},
project: function(point) {
point = this.rawProject(point);
if(this.transformation) {
point = this.transformation.transform(point);
}
return point;
},
unproject: function(point) {
if(this.transformation) {
point = this.transformation.untransform(point);
}
point = this.rawUnproject(point);
return point;
},
locationCoordinate: function(location) {
var point = new MM.Point(Math.PI * location.lon / 180.0,
Math.PI * location.lat / 180.0);
point = this.project(point);
return new MM.Coordinate(point.y, point.x, this.zoom);
},
coordinateLocation: function(coordinate) {
coordinate = coordinate.zoomTo(this.zoom);
var point = new MM.Point(coordinate.column, coordinate.row);
point = this.unproject(point);
return new MM.Location(180.0 * point.y / Math.PI,
180.0 * point.x / Math.PI);
}
};
// A projection for equilateral maps, based on longitude and latitude
MM.LinearProjection = function(zoom, transformation) {
MM.Projection.call(this, zoom, transformation);
};
// The Linear projection doesn't reproject points
MM.LinearProjection.prototype = {
rawProject: function(point) {
return new MM.Point(point.x, point.y);
},
rawUnproject: function(point) {
return new MM.Point(point.x, point.y);
}
};
MM.extend(MM.LinearProjection, MM.Projection);
MM.MercatorProjection = function(zoom, transformation) {
// super!
MM.Projection.call(this, zoom, transformation);
};
// Project lon/lat points into meters required for Mercator
MM.MercatorProjection.prototype = {
rawProject: function(point) {
return new MM.Point(point.x,
Math.log(Math.tan(0.25 * Math.PI + 0.5 * point.y)));
},
rawUnproject: function(point) {
return new MM.Point(point.x,
2 * Math.atan(Math.pow(Math.E, point.y)) - 0.5 * Math.PI);
}
};
MM.extend(MM.MercatorProjection, MM.Projection);
// Providers
// ---------
// Providers provide tile URLs and possibly elements for layers.
//
// MapProvider ->
// Template
//
MM.MapProvider = function(getTile) {
if (getTile) {
this.getTile = getTile;
}
};
MM.MapProvider.prototype = {
// these are limits for available *tiles*
// panning limits will be different (since you can wrap around columns)
// but if you put Infinity in here it will screw up sourceCoordinate
tileLimits: [
new MM.Coordinate(0,0,0), // top left outer
new MM.Coordinate(1,1,0).zoomTo(18) // bottom right inner
],
getTileUrl: function(coordinate) {
throw "Abstract method not implemented by subclass.";
},
getTile: function(coordinate) {
throw "Abstract method not implemented by subclass.";
},
// releaseTile is not required
releaseTile: function(element) { },
// use this to tell MapProvider that tiles only exist between certain zoom levels.
// should be set separately on Map to restrict interactive zoom/pan ranges
setZoomRange: function(minZoom, maxZoom) {
this.tileLimits[0] = this.tileLimits[0].zoomTo(minZoom);
this.tileLimits[1] = this.tileLimits[1].zoomTo(maxZoom);
},
// wrap column around the world if necessary
// return null if wrapped coordinate is outside of the tile limits
sourceCoordinate: function(coord) {
var TL = this.tileLimits[0].zoomTo(coord.zoom).container(),
BR = this.tileLimits[1].zoomTo(coord.zoom),
columnSize = Math.pow(2, coord.zoom),
wrappedColumn;
BR = new MM.Coordinate(Math.ceil(BR.row), Math.ceil(BR.column), Math.floor(BR.zoom));
if (coord.column < 0) {
wrappedColumn = ((coord.column % columnSize) + columnSize) % columnSize;
} else {
wrappedColumn = coord.column % columnSize;
}
if (coord.row < TL.row || coord.row >= BR.row) {
return null;
} else if (wrappedColumn < TL.column || wrappedColumn >= BR.column) {
return null;
} else {
return new MM.Coordinate(coord.row, wrappedColumn, coord.zoom);
}
}
};
/**
* FIXME: need a better explanation here! This is a pretty crucial part of
* understanding how to use ModestMaps.
*
* TemplatedMapProvider is a tile provider that generates tile URLs from a
* template string by replacing the following bits for each tile
* coordinate:
*
* {Z}: the tile's zoom level (from 1 to ~20)
* {X}: the tile's X, or column (from 0 to a very large number at higher
* zooms)
* {Y}: the tile's Y, or row (from 0 to a very large number at higher
* zooms)
*
* E.g.:
*
* var osm = new MM.TemplatedMapProvider("http://tile.openstreetmap.org/{Z}/{X}/{Y}.png");
*
* Or:
*
* var placeholder = new MM.TemplatedMapProvider("http://placehold.it/256/f0f/fff.png&text={Z}/{X}/{Y}");
*
*/
MM.Template = function(template, subdomains) {
var isQuadKey = template.match(/{(Q|quadkey)}/);
// replace Microsoft style substitution strings
if (isQuadKey) template = template
.replace('{subdomains}', '{S}')
.replace('{zoom}', '{Z}')
.replace('{quadkey}', '{Q}');
var hasSubdomains = (subdomains &&
subdomains.length && template.indexOf("{S}") >= 0);
function quadKey (row, column, zoom) {
var key = '';
for (var i = 1; i <= zoom; i++) {
key += (((row >> zoom - i) & 1) << 1) | ((column >> zoom - i) & 1);
}
return key || '0';
}
var getTileUrl = function(coordinate) {
var coord = this.sourceCoordinate(coordinate);
if (!coord) {
return null;
}
var base = template;
if (hasSubdomains) {
var index = parseInt(coord.zoom + coord.row + coord.column, 10) %
subdomains.length;
base = base.replace('{S}', subdomains[index]);
}
if (isQuadKey) {
return base
.replace('{Z}', coord.zoom.toFixed(0))
.replace('{Q}', quadKey(coord.row,
coord.column,
coord.zoom));
} else {
return base
.replace('{Z}', coord.zoom.toFixed(0))
.replace('{X}', coord.column.toFixed(0))
.replace('{Y}', coord.row.toFixed(0));
}
};
MM.MapProvider.call(this, getTileUrl);
};
MM.Template.prototype = {
// quadKey generator
getTile: function(coord) {
return this.getTileUrl(coord);
}
};
MM.extend(MM.Template, MM.MapProvider);
MM.TemplatedLayer = function(template, subdomains, name) {
return new MM.Layer(new MM.Template(template, subdomains), null, name);
};
// Event Handlers
// --------------
// A utility function for finding the offset of the
// mouse from the top-left of the page
MM.getMousePoint = function(e, map) {
// start with just the mouse (x, y)
var point = new MM.Point(e.clientX, e.clientY);
// correct for scrolled document
point.x += document.body.scrollLeft + document.documentElement.scrollLeft;
point.y += document.body.scrollTop + document.documentElement.scrollTop;
// correct for nested offsets in DOM
for (var node = map.parent; node; node = node.offsetParent) {
point.x -= node.offsetLeft;
point.y -= node.offsetTop;
}
return point;
};
MM.MouseWheelHandler = function() {
var handler = {},
map,
_zoomDiv,
prevTime,
precise = false;
function mouseWheel(e) {
var delta = 0;
prevTime = prevTime || new Date().getTime();
try {
_zoomDiv.scrollTop = 1000;
_zoomDiv.dispatchEvent(e);
delta = 1000 - _zoomDiv.scrollTop;
} catch (error) {
delta = e.wheelDelta || (-e.detail * 5);
}
// limit mousewheeling to once every 200ms
var timeSince = new Date().getTime() - prevTime;
var point = MM.getMousePoint(e, map);
if (Math.abs(delta) > 0 && (timeSince > 200) && !precise) {
map.zoomByAbout(delta > 0 ? 1 : -1, point);
prevTime = new Date().getTime();
} else if (precise) {
map.zoomByAbout(delta * 0.001, point);
}
// Cancel the event so that the page doesn't scroll
return MM.cancelEvent(e);
}
handler.init = function(x) {
map = x;
_zoomDiv = document.body.appendChild(document.createElement('div'));
_zoomDiv.style.cssText = 'visibility:hidden;top:0;height:0;width:0;overflow-y:scroll';
var innerDiv = _zoomDiv.appendChild(document.createElement('div'));
innerDiv.style.height = '2000px';
MM.addEvent(map.parent, 'mousewheel', mouseWheel);
return handler;
};
handler.precise = function(x) {
if (!arguments.length) return precise;
precise = x;
return handler;
};
handler.remove = function() {
MM.removeEvent(map.parent, 'mousewheel', mouseWheel);
_zoomDiv.parentNode.removeChild(_zoomDiv);
};
return handler;
};
MM.DoubleClickHandler = function() {
var handler = {},
map;
function doubleClick(e) {
// Ensure that this handler is attached once.
// Get the point on the map that was double-clicked
var point = MM.getMousePoint(e, map);
// use shift-double-click to zoom out
map.zoomByAbout(e.shiftKey ? -1 : 1, point);
return MM.cancelEvent(e);
}
handler.init = function(x) {
map = x;
MM.addEvent(map.parent, 'dblclick', doubleClick);
return handler;
};
handler.remove = function() {
MM.removeEvent(map.parent, 'dblclick', doubleClick);
};
return handler;
};
// Handle the use of mouse dragging to pan the map.
MM.DragHandler = function() {
var handler = {},
prevMouse,
map;
function mouseDown(e) {
if (e.shiftKey || e.button == 2) return;
MM.addEvent(document, 'mouseup', mouseUp);
MM.addEvent(document, 'mousemove', mouseMove);
prevMouse = new MM.Point(e.clientX, e.clientY);
map.parent.style.cursor = 'move';
return MM.cancelEvent(e);
}
function mouseUp(e) {
MM.removeEvent(document, 'mouseup', mouseUp);
MM.removeEvent(document, 'mousemove', mouseMove);
prevMouse = null;
map.parent.style.cursor = '';
return MM.cancelEvent(e);
}
function mouseMove(e) {
if (prevMouse) {
map.panBy(
e.clientX - prevMouse.x,
e.clientY - prevMouse.y);
prevMouse.x = e.clientX;
prevMouse.y = e.clientY;
prevMouse.t = +new Date();
}
return MM.cancelEvent(e);
}
handler.init = function(x) {
map = x;
MM.addEvent(map.parent, 'mousedown', mouseDown);
return handler;
};
handler.remove = function() {
MM.removeEvent(map.parent, 'mousedown', mouseDown);
};
return handler;
};
MM.MouseHandler = function() {
var handler = {},
map,
handlers;
handler.init = function(x) {
map = x;
handlers = [
MM.DragHandler().init(map),
MM.DoubleClickHandler().init(map),
MM.MouseWheelHandler().init(map)
];
return handler;
};
handler.remove = function() {
for (var i = 0; i < handlers.length; i++) {
handlers[i].remove();
}
return handler;
};
return handler;
};
MM.TouchHandler = function() {
var handler = {},
map,
maxTapTime = 250,
maxTapDistance = 30,
maxDoubleTapDelay = 350,
locations = {},
taps = [],
snapToZoom = true,
wasPinching = false,
lastPinchCenter = null;
function isTouchable () {
var el = document.createElement('div');
el.setAttribute('ongesturestart', 'return;');
return (typeof el.ongesturestart === 'function');
}
function updateTouches(e) {
for (var i = 0; i < e.touches.length; i += 1) {
var t = e.touches[i];
if (t.identifier in locations) {
var l = locations[t.identifier];
l.x = t.clientX;
l.y = t.clientY;
l.scale = e.scale;
}
else {
locations[t.identifier] = {
scale: e.scale,
startPos: { x: t.clientX, y: t.clientY },
x: t.clientX,
y: t.clientY,
time: new Date().getTime()
};
}
}
}
// Test whether touches are from the same source -
// whether this is the same touchmove event.
function sameTouch (event, touch) {
return (event && event.touch) &&
(touch.identifier == event.touch.identifier);
}
function touchStart(e) {
updateTouches(e);
}
function touchMove(e) {
switch (e.touches.length) {
case 1:
onPanning(e.touches[0]);
break;
case 2:
onPinching(e);
break;
}
updateTouches(e);
return MM.cancelEvent(e);
}
function touchEnd(e) {
var now = new Date().getTime();
// round zoom if we're done pinching
if (e.touches.length === 0 && wasPinching) {
onPinched(lastPinchCenter);
}
// Look at each changed touch in turn.
for (var i = 0; i < e.changedTouches.length; i += 1) {
var t = e.changedTouches[i],
loc = locations[t.identifier];
// if we didn't see this one (bug?)
// or if it was consumed by pinching already
// just skip to the next one
if (!loc || loc.wasPinch) {
continue;
}
// we now know we have an event object and a
// matching touch that's just ended. Let's see
// what kind of event it is based on how long it
// lasted and how far it moved.
var pos = { x: t.clientX, y: t.clientY },
time = now - loc.time,
travel = MM.Point.distance(pos, loc.startPos);
if (travel > maxTapDistance) {
// we will to assume that the drag has been handled separately
} else if (time > maxTapTime) {
// close in space, but not in time: a hold
pos.end = now;
pos.duration = time;
onHold(pos);
} else {
// close in both time and space: a tap
pos.time = now;
onTap(pos);
}
}
// Weird, sometimes an end event doesn't get thrown
// for a touch that nevertheless has disappeared.
// Still, this will eventually catch those ids:
var validTouchIds = {};
for (var j = 0; j < e.touches.length; j++) {
validTouchIds[e.touches[j].identifier] = true;
}
for (var id in locations) {
if (!(id in validTouchIds)) {
delete validTouchIds[id];
}
}
return MM.cancelEvent(e);
}
function onHold (hold) {
// TODO
}
// Handle a tap event - mainly watch for a doubleTap
function onTap(tap) {
if (taps.length &&
(tap.time - taps[0].time) < maxDoubleTapDelay) {
onDoubleTap(tap);
taps = [];
return;
}
taps = [tap];
}
// Handle a double tap by zooming in a single zoom level to a
// round zoom.
function onDoubleTap(tap) {
var z = map.getZoom(), // current zoom
tz = Math.round(z) + 1, // target zoom
dz = tz - z; // desired delate
// zoom in to a round number
var p = new MM.Point(tap.x, tap.y);
map.zoomByAbout(dz, p);
}
// Re-transform the actual map parent's CSS transformation
function onPanning (touch) {
var pos = { x: touch.clientX, y: touch.clientY },
prev = locations[touch.identifier];
map.panBy(pos.x - prev.x, pos.y - prev.y);
}
function onPinching(e) {
// use the first two touches and their previous positions
var t0 = e.touches[0],
t1 = e.touches[1],
p0 = new MM.Point(t0.clientX, t0.clientY),
p1 = new MM.Point(t1.clientX, t1.clientY),
l0 = locations[t0.identifier],
l1 = locations[t1.identifier];
// mark these touches so they aren't used as taps/holds
l0.wasPinch = true;
l1.wasPinch = true;
// scale about the center of these touches
var center = MM.Point.interpolate(p0, p1, 0.5);
map.zoomByAbout(
Math.log(e.scale) / Math.LN2 -
Math.log(l0.scale) / Math.LN2,
center );
// pan from the previous center of these touches
var prevCenter = MM.Point.interpolate(l0, l1, 0.5);
map.panBy(center.x - prevCenter.x,
center.y - prevCenter.y);
wasPinching = true;
lastPinchCenter = center;
}
// When a pinch event ends, round the zoom of the map.
function onPinched(p) {
// TODO: easing
if (snapToZoom) {
var z = map.getZoom(), // current zoom
tz =Math.round(z); // target zoom
map.zoomByAbout(tz - z, p);
}
wasPinching = false;
}
handler.init = function(x) {
map = x;
// Fail early if this isn't a touch device.
if (!isTouchable()) return handler;
MM.addEvent(map.parent, 'touchstart', touchStart);
MM.addEvent(map.parent, 'touchmove', touchMove);
MM.addEvent(map.parent, 'touchend', touchEnd);
return handler;
};
handler.remove = function() {
// Fail early if this isn't a touch device.
if (!isTouchable()) return handler;
MM.removeEvent(map.parent, 'touchstart', touchStart);
MM.removeEvent(map.parent, 'touchmove', touchMove);
MM.removeEvent(map.parent, 'touchend', touchEnd);
return handler;
};
return handler;
};
// CallbackManager
// ---------------
// A general-purpose event binding manager used by `Map`
// and `RequestManager`
// Construct a new CallbackManager, with an list of
// supported events.
MM.CallbackManager = function(owner, events) {
this.owner = owner;
this.callbacks = {};
for (var i = 0; i < events.length; i++) {
this.callbacks[events[i]] = [];
}
};
// CallbackManager does simple event management for modestmaps
MM.CallbackManager.prototype = {
// The element on which callbacks will be triggered.
owner: null,
// An object of callbacks in the form
//
// { event: function }
callbacks: null,
// Add a callback to this object - where the `event` is a string of
// the event name and `callback` is a function.
addCallback: function(event, callback) {
if (typeof(callback) == 'function' && this.callbacks[event]) {
this.callbacks[event].push(callback);
}
},
// Remove a callback. The given function needs to be equal (`===`) to
// the callback added in `addCallback`, so named functions should be
// used as callbacks.
removeCallback: function(event, callback) {
if (typeof(callback) == 'function' && this.callbacks[event]) {
var cbs = this.callbacks[event],
len = cbs.length;
for (var i = 0; i < len; i++) {
if (cbs[i] === callback) {
cbs.splice(i,1);
break;
}
}
}
},
// Trigger a callback, passing it an object or string from the second
// argument.
dispatchCallback: function(event, message) {
if(this.callbacks[event]) {
for (var i = 0; i < this.callbacks[event].length; i += 1) {
try {
this.callbacks[event][i](this.owner, message);
} catch(e) {
//console.log(e);
// meh
}
}
}
}
};
// RequestManager
// --------------
// an image loading queue
MM.RequestManager = function() {
// The loading bay is a document fragment to optimize appending, since
// the elements within are invisible. See
// [this blog post](http://ejohn.org/blog/dom-documentfragments/).
this.loadingBay = document.createDocumentFragment();
this.requestsById = {};
this.openRequestCount = 0;
this.maxOpenRequests = 4;
this.requestQueue = [];
this.callbackManager = new MM.CallbackManager(this, [
'requestcomplete', 'requesterror']);
};
MM.RequestManager.prototype = {
// DOM element, hidden, for making sure images dispatch complete events
loadingBay: null,
// all known requests, by ID
requestsById: null,
// current pending requests
requestQueue: null,
// current open requests (children of loadingBay)
openRequestCount: null,
// the number of open requests permitted at one time, clamped down
// because of domain-connection limits.
maxOpenRequests: null,
// for dispatching 'requestcomplete'
callbackManager: null,
addCallback: function(event, callback) {
this.callbackManager.addCallback(event,callback);
},
removeCallback: function(event, callback) {
this.callbackManager.removeCallback(event,callback);
},
dispatchCallback: function(event, message) {
this.callbackManager.dispatchCallback(event,message);
},
// Clear everything in the queue by excluding nothing
clear: function() {
this.clearExcept({});
},
clearRequest: function(id) {
if(id in this.requestsById) {
delete this.requestsById[id];
}
for(var i = 0; i < this.requestQueue.length; i++) {
var request = this.requestQueue[i];
if(request && request.id == id) {
this.requestQueue[i] = null;
}
}
},
// Clear everything in the queue except for certain keys, specified
// by an object of the form
//
// { key: throwawayvalue }
clearExcept: function(validIds) {
// clear things from the queue first...
for (var i = 0; i < this.requestQueue.length; i++) {
var request = this.requestQueue[i];
if (request && !(request.id in validIds)) {
this.requestQueue[i] = null;
}
}
// then check the loadingBay...
var openRequests = this.loadingBay.childNodes;
for (var j = openRequests.length-1; j >= 0; j--) {
var img = openRequests[j];
if (!(img.id in validIds)) {
this.loadingBay.removeChild(img);
this.openRequestCount--;
/* console.log(this.openRequestCount + " open requests"); */
img.src = img.coord = img.onload = img.onerror = null;
}
}
// hasOwnProperty protects against prototype additions
// > "The standard describes an augmentable Object.prototype.
// Ignore standards at your own peril."
// -- http://www.yuiblog.com/blog/2006/09/26/for-in-intrigue/
for (var id in this.requestsById) {
if (!(id in validIds)) {
if (this.requestsById.hasOwnProperty(id)) {
var requestToRemove = this.requestsById[id];
// whether we've done the request or not...
delete this.requestsById[id];
if (requestToRemove !== null) {
requestToRemove =
requestToRemove.id =
requestToRemove.coord =
requestToRemove.url = null;
}
}
}
}
},
// Given a tile id, check whether the RequestManager is currently
// requesting it and waiting for the result.
hasRequest: function(id) {
return (id in this.requestsById);
},
// * TODO: remove dependency on coord (it's for sorting, maybe call it data?)
// * TODO: rename to requestImage once it's not tile specific
requestTile: function(id, coord, url) {
if (!(id in this.requestsById)) {
var request = { id: id, coord: coord.copy(), url: url };
// if there's no url just make sure we don't request this image again
this.requestsById[id] = request;
if (url) {
this.requestQueue.push(request);
/* console.log(this.requestQueue.length + ' pending requests'); */
}
}
},
getProcessQueue: function() {
// let's only create this closure once...
if (!this._processQueue) {
var theManager = this;
this._processQueue = function() {
theManager.processQueue();
};
}
return this._processQueue;
},
// Select images from the `requestQueue` and create image elements for
// them, attaching their load events to the function returned by
// `this.getLoadComplete()` so that they can be added to the map.
processQueue: function(sortFunc) {
// When the request queue fills up beyond 8, start sorting the
// requests so that spiral-loading or another pattern can be used.
if (sortFunc && this.requestQueue.length > 8) {
this.requestQueue.sort(sortFunc);
}
while (this.openRequestCount < this.maxOpenRequests && this.requestQueue.length > 0) {
var request = this.requestQueue.pop();
if (request) {
this.openRequestCount++;
/* console.log(this.openRequestCount + ' open requests'); */
// JSLitmus benchmark shows createElement is a little faster than
// new Image() in Firefox and roughly the same in Safari:
// http://tinyurl.com/y9wz2jj http://tinyurl.com/yes6rrt
var img = document.createElement('img');
// FIXME: id is technically not unique in document if there
// are two Maps but toKey is supposed to be fast so we're trying
// to avoid a prefix ... hence we can't use any calls to
// `document.getElementById()` to retrieve images
img.id = request.id;
img.style.position = 'absolute';
// * FIXME: store this elsewhere to avoid scary memory leaks?
// * FIXME: call this 'data' not 'coord' so that RequestManager is less Tile-centric?
img.coord = request.coord;
// add it to the DOM in a hidden layer, this is a bit of a hack, but it's
// so that the event we get in image.onload has srcElement assigned in IE6
this.loadingBay.appendChild(img);
// set these before img.src to avoid missing an img that's already cached
img.onload = img.onerror = this.getLoadComplete();
img.src = request.url;
// keep things tidy
request = request.id = request.coord = request.url = null;
}
}
},
_loadComplete: null,
// Get the singleton `_loadComplete` function that is called on image
// load events, either removing them from the queue and dispatching an
// event to add them to the map, or deleting them if the image failed
// to load.
getLoadComplete: function() {
// let's only create this closure once...
if (!this._loadComplete) {
var theManager = this;
this._loadComplete = function(e) {
// this is needed because we don't use MM.addEvent for images
e = e || window.event;
// srcElement for IE, target for FF, Safari etc.
var img = e.srcElement || e.target;
// unset these straight away so we don't call this twice
img.onload = img.onerror = null;
// pull it back out of the (hidden) DOM
// so that draw will add it correctly later
theManager.loadingBay.removeChild(img);
theManager.openRequestCount--;
delete theManager.requestsById[img.id];
/* console.log(theManager.openRequestCount + ' open requests'); */
// NB:- complete is also true onerror if we got a 404
if (e.type === 'load' && (img.complete ||
(img.readyState && img.readyState == 'complete'))) {
theManager.dispatchCallback('requestcomplete', img);
} else {
// if it didn't finish clear its src to make sure it
// really stops loading
// FIXME: we'll never retry because this id is still
// in requestsById - is that right?
theManager.dispatchCallback('requesterror', {
element: img,
url: ('' + img.src)
});
img.src = null;
}
// keep going in the same order
// use `setTimeout()` to avoid the IE recursion limit, see
// http://cappuccino.org/discuss/2010/03/01/internet-explorer-global-variables-and-stack-overflows/
// and https://github.com/stamen/modestmaps-js/issues/12
setTimeout(theManager.getProcessQueue(), 0);
};
}
return this._loadComplete;
}
};
// Layer
MM.Layer = function(provider, parent, name) {
this.parent = parent || document.createElement('div');
this.parent.style.cssText = 'position: absolute; top: 0px; left: 0px; width: 100%; height: 100%; margin: 0; padding: 0; z-index: 0';
this.name = name;
this.levels = {};
this.requestManager = new MM.RequestManager();
this.requestManager.addCallback('requestcomplete', this.getTileComplete());
this.requestManager.addCallback('requesterror', this.getTileError());
if (provider) this.setProvider(provider);
};
MM.Layer.prototype = {
map: null, // TODO: remove
parent: null,
name: null,
enabled: true,
tiles: null,
levels: null,
requestManager: null,
provider: null,
_tileComplete: null,
getTileComplete: function() {
if (!this._tileComplete) {
var theLayer = this;
this._tileComplete = function(manager, tile) {
theLayer.tiles[tile.id] = tile;
theLayer.positionTile(tile);
// Support style transition if available.
tile.style.visibility = 'inherit';
tile.className = 'map-tile-loaded';
};
}
return this._tileComplete;
},
getTileError: function() {
if (!this._tileError) {
var theLayer = this;
this._tileError = function(manager, tile) {
tile.onload = tile.onerror = null;
theLayer.tiles[tile.element.id] = tile.element;
theLayer.positionTile(tile.element);
tile.element.style.visibility = 'hidden';
};
}
return this._tileError;
},
draw: function() {
if (!this.enabled || !this.map) return;
// compares manhattan distance from center of
// requested tiles to current map center
// NB:- requested tiles are *popped* from queue, so we do a descending sort
var theCoord = this.map.coordinate.zoomTo(Math.round(this.map.coordinate.zoom));
function centerDistanceCompare(r1, r2) {
if (r1 && r2) {
var c1 = r1.coord;
var c2 = r2.coord;
if (c1.zoom == c2.zoom) {
var ds1 = Math.abs(theCoord.row - c1.row - 0.5) +
Math.abs(theCoord.column - c1.column - 0.5);
var ds2 = Math.abs(theCoord.row - c2.row - 0.5) +
Math.abs(theCoord.column - c2.column - 0.5);
return ds1 < ds2 ? 1 : ds1 > ds2 ? -1 : 0;
} else {
return c1.zoom < c2.zoom ? 1 : c1.zoom > c2.zoom ? -1 : 0;
}
}
return r1 ? 1 : r2 ? -1 : 0;
}
// if we're in between zoom levels, we need to choose the nearest:
var baseZoom = Math.round(this.map.coordinate.zoom);
// these are the top left and bottom right tile coordinates
// we'll be loading everything in between:
var startCoord = this.map.pointCoordinate(new MM.Point(0,0))
.zoomTo(baseZoom).container();
var endCoord = this.map.pointCoordinate(this.map.dimensions)
.zoomTo(baseZoom).container().right().down();
// tiles with invalid keys will be removed from visible levels
// requests for tiles with invalid keys will be canceled
// (this object maps from a tile key to a boolean)
var validTileKeys = { };
// make sure we have a container for tiles in the current level
var levelElement = this.createOrGetLevel(startCoord.zoom);
// use this coordinate for generating keys, parents and children:
var tileCoord = startCoord.copy();
for (tileCoord.column = startCoord.column;
tileCoord.column <= endCoord.column; tileCoord.column++) {
for (tileCoord.row = startCoord.row;
tileCoord.row <= endCoord.row; tileCoord.row++) {
var validKeys = this.inventoryVisibleTile(levelElement, tileCoord);
while (validKeys.length) {
validTileKeys[validKeys.pop()] = true;
}
}
}
// i from i to zoom-5 are levels that would be scaled too big,
// i from zoom + 2 to levels. length are levels that would be
// scaled too small (and tiles would be too numerous)
for (var name in this.levels) {
if (this.levels.hasOwnProperty(name)) {
var zoom = parseInt(name,10);
if (zoom >= startCoord.zoom - 5 && zoom < startCoord.zoom + 2) {
continue;
}
var level = this.levels[name];
level.style.display = 'none';
var visibleTiles = this.tileElementsInLevel(level);
while (visibleTiles.length) {
this.provider.releaseTile(visibleTiles[0].coord);
this.requestManager.clearRequest(visibleTiles[0].coord.toKey());
level.removeChild(visibleTiles[0]);
visibleTiles.shift();
}
}
}
// levels we want to see, if they have tiles in validTileKeys
var minLevel = startCoord.zoom - 5;
var maxLevel = startCoord.zoom + 2;
for (var z = minLevel; z < maxLevel; z++) {
this.adjustVisibleLevel(this.levels[z], z, validTileKeys);
}
// cancel requests that aren't visible:
this.requestManager.clearExcept(validTileKeys);
// get newly requested tiles, sort according to current view:
this.requestManager.processQueue(centerDistanceCompare);
},
// For a given tile coordinate in a given level element, ensure that it's
// correctly represented in the DOM including potentially-overlapping
// parent and child tiles for pyramid loading.
//
// Return a list of valid (i.e. loadable?) tile keys.
inventoryVisibleTile: function(layer_element, tile_coord) {
var tile_key = tile_coord.toKey(),
valid_tile_keys = [tile_key];
// Check that the needed tile already exists someplace - add it to the DOM if it does.
if (tile_key in this.tiles) {
var tile = this.tiles[tile_key];
// ensure it's in the DOM:
if (tile.parentNode != layer_element) {
layer_element.appendChild(tile);
// if the provider implements reAddTile(), call it
if ("reAddTile" in this.provider) {
this.provider.reAddTile(tile_key, tile_coord, tile);
}
}
return valid_tile_keys;
}
// Check that the needed tile has even been requested at all.
if (!this.requestManager.hasRequest(tile_key)) {
var tileToRequest = this.provider.getTile(tile_coord);
if (typeof tileToRequest == 'string') {
this.addTileImage(tile_key, tile_coord, tileToRequest);
// tile must be truish
} else if (tileToRequest) {
this.addTileElement(tile_key, tile_coord, tileToRequest);
}
}
// look for a parent tile in our image cache
var tileCovered = false;
var maxStepsOut = tile_coord.zoom;
for (var pz = 1; pz <= maxStepsOut; pz++) {
var parent_coord = tile_coord.zoomBy(-pz).container();
var parent_key = parent_coord.toKey();
// only mark it valid if we have it already
if (parent_key in this.tiles) {
valid_tile_keys.push(parent_key);
tileCovered = true;
break;
}
}
// if we didn't find a parent, look at the children:
if (!tileCovered) {
var child_coord = tile_coord.zoomBy(1);
// mark everything valid whether or not we have it:
valid_tile_keys.push(child_coord.toKey());
child_coord.column += 1;
valid_tile_keys.push(child_coord.toKey());
child_coord.row += 1;
valid_tile_keys.push(child_coord.toKey());
child_coord.column -= 1;
valid_tile_keys.push(child_coord.toKey());
}
return valid_tile_keys;
},
tileElementsInLevel: function(level) {
// this is somewhat future proof, we're looking for DOM elements
// not necessarily <img> elements
var tiles = [];
for (var tile = level.firstChild; tile; tile = tile.nextSibling) {
if (tile.nodeType == 1) {
tiles.push(tile);
}
}
return tiles;
},
/**
* For a given level, adjust visibility as a whole and discard individual
* tiles based on values in valid_tile_keys from inventoryVisibleTile().
*/
adjustVisibleLevel: function(level, zoom, valid_tile_keys) {
// no tiles for this level yet
if (!level) return;
var scale = 1;
var theCoord = this.map.coordinate.copy();
if (level.childNodes.length > 0) {
level.style.display = 'block';
scale = Math.pow(2, this.map.coordinate.zoom - zoom);
theCoord = theCoord.zoomTo(zoom);
} else {
level.style.display = 'none';
return false;
}
var tileWidth = this.map.tileSize.x * scale;
var tileHeight = this.map.tileSize.y * scale;
var center = new MM.Point(this.map.dimensions.x/2, this.map.dimensions.y/2);
var tiles = this.tileElementsInLevel(level);
while (tiles.length) {
var tile = tiles.pop();
if (!valid_tile_keys[tile.id]) {
this.provider.releaseTile(tile.coord);
this.requestManager.clearRequest(tile.coord.toKey());
level.removeChild(tile);
} else {
// position tiles
MM.moveElement(tile, {
x: Math.round(center.x +
(tile.coord.column - theCoord.column) * tileWidth),
y: Math.round(center.y +
(tile.coord.row - theCoord.row) * tileHeight),
scale: scale,
// TODO: pass only scale or only w/h
width: this.map.tileSize.x,
height: this.map.tileSize.y
});
}
}
},
createOrGetLevel: function(zoom) {
if (zoom in this.levels) {
return this.levels[zoom];
}
var level = document.createElement('div');
level.id = this.parent.id + '-zoom-' + zoom;
level.style.cssText = 'position: absolute; top: 0px; left: 0px; width: 100%; height: 100%; margin: 0; padding: 0;';
level.style.zIndex = zoom;
this.parent.appendChild(level);
this.levels[zoom] = level;
return level;
},
addTileImage: function(key, coord, url) {
this.requestManager.requestTile(key, coord, url);
},
addTileElement: function(key, coordinate, element) {
// Expected in draw()
element.id = key;
element.coord = coordinate.copy();
this.positionTile(element);
},
positionTile: function(tile) {
// position this tile (avoids a full draw() call):
var theCoord = this.map.coordinate.zoomTo(tile.coord.zoom);
// Start tile positioning and prevent drag for modern browsers
tile.style.cssText = 'position:absolute;-webkit-user-select:none;' +
'-webkit-user-drag:none;-moz-user-drag:none;-webkit-transform-origin:0 0;' +
'-moz-transform-origin:0 0;-o-transform-origin:0 0;-ms-transform-origin:0 0;' +
'width:' + this.map.tileSize.x + 'px; height: ' + this.map.tileSize.y + 'px;';
// Prevent drag for IE
tile.ondragstart = function() { return false; };
var scale = Math.pow(2, this.map.coordinate.zoom - tile.coord.zoom);
MM.moveElement(tile, {
x: Math.round((this.map.dimensions.x/2) +
(tile.coord.column - theCoord.column) * this.map.tileSize.x),
y: Math.round((this.map.dimensions.y/2) +
(tile.coord.row - theCoord.row) * this.map.tileSize.y),
scale: scale,
// TODO: pass only scale or only w/h
width: this.map.tileSize.x,
height: this.map.tileSize.y
});
// add tile to its level
var theLevel = this.levels[tile.coord.zoom];
theLevel.appendChild(tile);
// ensure the level is visible if it's still the current level
if (Math.round(this.map.coordinate.zoom) == tile.coord.zoom) {
theLevel.style.display = 'block';
}
// request a lazy redraw of all levels
// this will remove tiles that were only visible
// to cover this tile while it loaded:
this.requestRedraw();
},
_redrawTimer: undefined,
requestRedraw: function() {
// we'll always draw within 1 second of this request,
// sometimes faster if there's already a pending redraw
// this is used when a new tile arrives so that we clear
// any parent/child tiles that were only being displayed
// until the tile loads at the right zoom level
if (!this._redrawTimer) {
this._redrawTimer = setTimeout(this.getRedraw(), 1000);
}
},
_redraw: null,
getRedraw: function() {
// let's only create this closure once...
if (!this._redraw) {
var theLayer = this;
this._redraw = function() {
theLayer.draw();
theLayer._redrawTimer = 0;
};
}
return this._redraw;
},
setProvider: function(newProvider) {
var firstProvider = (this.provider === null);
// if we already have a provider the we'll need to
// clear the DOM, cancel requests and redraw
if (!firstProvider) {
this.requestManager.clear();
for (var name in this.levels) {
if (this.levels.hasOwnProperty(name)) {
var level = this.levels[name];
while (level.firstChild) {
this.provider.releaseTile(level.firstChild.coord);
level.removeChild(level.firstChild);
}
}
}
}
// first provider or not we'll init/reset some values...
this.tiles = {};
// for later: check geometry of old provider and set a new coordinate center
// if needed (now? or when?)
this.provider = newProvider;
if (!firstProvider) {
this.draw();
}
},
// Enable a layer and show its dom element
enable: function() {
this.enabled = true;
this.parent.style.display = '';
this.draw();
return this;
},
// Disable a layer, don't display in DOM, clear all requests
disable: function() {
this.enabled = false;
this.requestManager.clear();
this.parent.style.display = 'none';
return this;
},
// Remove this layer from the DOM, cancel all of its requests
// and unbind any callbacks that are bound to it.
destroy: function() {
this.requestManager.clear();
this.requestManager.removeCallback('requestcomplete', this.getTileComplete());
this.requestManager.removeCallback('requesterror', this.getTileError());
// TODO: does requestManager need a destroy function too?
this.provider = null;
// If this layer was ever attached to the DOM, detach it.
if (this.parent.parentNode) {
this.parent.parentNode.removeChild(this.parent);
}
this.map = null;
}
};
// Map
// Instance of a map intended for drawing to a div.
//
// * `parent` (required DOM element)
// Can also be an ID of a DOM element
// * `layerOrLayers` (required MM.Layer or Array of MM.Layers)
// each one must implement draw(), destroy(), have a .parent DOM element and a .map property
// (an array of URL templates or MM.MapProviders is also acceptable)
// * `dimensions` (optional Point)
// Size of map to create
// * `eventHandlers` (optional Array)
// If empty or null MouseHandler will be used
// Otherwise, each handler will be called with init(map)
MM.Map = function(parent, layerOrLayers, dimensions, eventHandlers) {
if (typeof parent == 'string') {
parent = document.getElementById(parent);
if (!parent) {
throw 'The ID provided to modest maps could not be found.';
}
}
this.parent = parent;
// we're no longer adding width and height to parent.style but we still
// need to enforce padding, overflow and position otherwise everything screws up
// TODO: maybe console.warn if the current values are bad?
this.parent.style.padding = '0';
this.parent.style.overflow = 'hidden';
var position = MM.getStyle(this.parent, 'position');
if (position != 'relative' && position != 'absolute') {
this.parent.style.position = 'relative';
}
this.layers = [];
if (!layerOrLayers) {
layerOrLayers = [];
}
if (!(layerOrLayers instanceof Array)) {
layerOrLayers = [ layerOrLayers ];
}
for (var i = 0; i < layerOrLayers.length; i++) {
this.addLayer(layerOrLayers[i]);
}
// default to Google-y Mercator style maps
this.projection = new MM.MercatorProjection(0,
MM.deriveTransformation(-Math.PI, Math.PI, 0, 0,
Math.PI, Math.PI, 1, 0,
-Math.PI, -Math.PI, 0, 1));
this.tileSize = new MM.Point(256, 256);
// default 0-18 zoom level
// with infinite horizontal pan and clamped vertical pan
this.coordLimits = [
new MM.Coordinate(0,-Infinity,0), // top left outer
new MM.Coordinate(1,Infinity,0).zoomTo(18) // bottom right inner
];
// eyes towards null island
this.coordinate = new MM.Coordinate(0.5, 0.5, 0);
// if you don't specify dimensions we assume you want to fill the parent
// unless the parent has no w/h, in which case we'll still use a default
if (!dimensions) {
dimensions = new MM.Point(this.parent.offsetWidth,
this.parent.offsetHeight);
this.autoSize = true;
// use destroy to get rid of this handler from the DOM
MM.addEvent(window, 'resize', this.windowResize());
} else {
this.autoSize = false;
// don't call setSize here because it calls draw()
this.parent.style.width = Math.round(dimensions.x) + 'px';
this.parent.style.height = Math.round(dimensions.y) + 'px';
}
this.dimensions = dimensions;
this.callbackManager = new MM.CallbackManager(this, [
'zoomed',
'panned',
'centered',
'extentset',
'resized',
'drawn'
]);
// set up handlers last so that all required attributes/functions are in place if needed
if (eventHandlers === undefined) {
this.eventHandlers = [
MM.MouseHandler().init(this),
MM.TouchHandler().init(this)
];
} else {
this.eventHandlers = eventHandlers;
if (eventHandlers instanceof Array) {
for (var j = 0; j < eventHandlers.length; j++) {
eventHandlers[j].init(this);
}
}
}
};
MM.Map.prototype = {
parent: null, // DOM Element
dimensions: null, // MM.Point with x/y size of parent element
projection: null, // MM.Projection of first known layer
coordinate: null, // Center of map MM.Coordinate with row/column/zoom
tileSize: null, // MM.Point with x/y size of tiles
coordLimits: null, // Array of [ topLeftOuter, bottomLeftInner ] MM.Coordinates
layers: null, // Array of MM.Layer (interface = .draw(), .destroy(), .parent and .map)
callbackManager: null, // MM.CallbackManager, handles map events
eventHandlers: null, // Array of interaction handlers, just a MM.MouseHandler by default
autoSize: null, // Boolean, true if we have a window resize listener
toString: function() {
return 'Map(#' + this.parent.id + ')';
},
// callbacks...
addCallback: function(event, callback) {
this.callbackManager.addCallback(event, callback);
return this;
},
removeCallback: function(event, callback) {
this.callbackManager.removeCallback(event, callback);
return this;
},
dispatchCallback: function(event, message) {
this.callbackManager.dispatchCallback(event, message);
return this;
},
windowResize: function() {
if (!this._windowResize) {
var theMap = this;
this._windowResize = function(event) {
// don't call setSize here because it sets parent.style.width/height
// and setting the height breaks percentages and default styles
theMap.dimensions = new MM.Point(theMap.parent.offsetWidth, theMap.parent.offsetHeight);
theMap.draw();
theMap.dispatchCallback('resized', [theMap.dimensions]);
};
}
return this._windowResize;
},
// A convenience function to restrict interactive zoom ranges.
// (you should also adjust map provider to restrict which tiles get loaded,
// or modify map.coordLimits and provider.tileLimits for finer control)
setZoomRange: function(minZoom, maxZoom) {
this.coordLimits[0] = this.coordLimits[0].zoomTo(minZoom);
this.coordLimits[1] = this.coordLimits[1].zoomTo(maxZoom);
return this;
},
// zooming
zoomBy: function(zoomOffset) {
this.coordinate = this.enforceLimits(this.coordinate.zoomBy(zoomOffset));
MM.getFrame(this.getRedraw());
this.dispatchCallback('zoomed', zoomOffset);
return this;
},
zoomIn: function() { return this.zoomBy(1); },
zoomOut: function() { return this.zoomBy(-1); },
setZoom: function(z) { return this.zoomBy(z - this.coordinate.zoom); },
zoomByAbout: function(zoomOffset, point) {
var location = this.pointLocation(point);
this.coordinate = this.enforceLimits(this.coordinate.zoomBy(zoomOffset));
var newPoint = this.locationPoint(location);
this.dispatchCallback('zoomed', zoomOffset);
return this.panBy(point.x - newPoint.x, point.y - newPoint.y);
},
// panning
panBy: function(dx, dy) {
this.coordinate.column -= dx / this.tileSize.x;
this.coordinate.row -= dy / this.tileSize.y;
this.coordinate = this.enforceLimits(this.coordinate);
// Defer until the browser is ready to draw.
MM.getFrame(this.getRedraw());
this.dispatchCallback('panned', [dx, dy]);
return this;
},
panLeft: function() { return this.panBy(100, 0); },
panRight: function() { return this.panBy(-100, 0); },
panDown: function() { return this.panBy(0, -100); },
panUp: function() { return this.panBy(0, 100); },
// positioning
setCenter: function(location) {
return this.setCenterZoom(location, this.coordinate.zoom);
},
setCenterZoom: function(location, zoom) {
this.coordinate = this.projection.locationCoordinate(location).zoomTo(parseFloat(zoom) || 0);
this.coordinate = this.enforceLimits(this.coordinate);
MM.getFrame(this.getRedraw());
this.dispatchCallback('centered', [location, zoom]);
return this;
},
extentCoordinate: function(locations, precise) {
// coerce locations to an array if it's a Extent instance
if (locations instanceof MM.Extent) {
locations = locations.toArray();
}
var TL, BR;
for (var i = 0; i < locations.length; i++) {
var coordinate = this.projection.locationCoordinate(locations[i]);
if (TL) {
TL.row = Math.min(TL.row, coordinate.row);
TL.column = Math.min(TL.column, coordinate.column);
TL.zoom = Math.min(TL.zoom, coordinate.zoom);
BR.row = Math.max(BR.row, coordinate.row);
BR.column = Math.max(BR.column, coordinate.column);
BR.zoom = Math.max(BR.zoom, coordinate.zoom);
}
else {
TL = coordinate.copy();
BR = coordinate.copy();
}
}
var width = this.dimensions.x + 1;
var height = this.dimensions.y + 1;
// multiplication factor between horizontal span and map width
var hFactor = (BR.column - TL.column) / (width / this.tileSize.x);
// multiplication factor expressed as base-2 logarithm, for zoom difference
var hZoomDiff = Math.log(hFactor) / Math.log(2);
// possible horizontal zoom to fit geographical extent in map width
var hPossibleZoom = TL.zoom - (precise ? hZoomDiff : Math.ceil(hZoomDiff));
// multiplication factor between vertical span and map height
var vFactor = (BR.row - TL.row) / (height / this.tileSize.y);
// multiplication factor expressed as base-2 logarithm, for zoom difference
var vZoomDiff = Math.log(vFactor) / Math.log(2);
// possible vertical zoom to fit geographical extent in map height
var vPossibleZoom = TL.zoom - (precise ? vZoomDiff : Math.ceil(vZoomDiff));
// initial zoom to fit extent vertically and horizontally
var initZoom = Math.min(hPossibleZoom, vPossibleZoom);
// additionally, make sure it's not outside the boundaries set by map limits
initZoom = Math.min(initZoom, this.coordLimits[1].zoom);
initZoom = Math.max(initZoom, this.coordLimits[0].zoom);
// coordinate of extent center
var centerRow = (TL.row + BR.row) / 2;
var centerColumn = (TL.column + BR.column) / 2;
var centerZoom = TL.zoom;
return new MM.Coordinate(centerRow, centerColumn, centerZoom).zoomTo(initZoom);
},
setExtent: function(locations, precise) {
this.coordinate = this.extentCoordinate(locations, precise);
this.coordinate = this.enforceLimits(this.coordinate);
MM.getFrame(this.getRedraw());
this.dispatchCallback('extentset', locations);
return this;
},
// Resize the map's container `<div>`, redrawing the map and triggering
// `resized` to make sure that the map's presentation is still correct.
setSize: function(dimensions) {
// Ensure that, whether a raw object or a Point object is passed,
// this.dimensions will be a Point.
this.dimensions = new MM.Point(dimensions.x, dimensions.y);
this.parent.style.width = Math.round(this.dimensions.x) + 'px';
this.parent.style.height = Math.round(this.dimensions.y) + 'px';
if (this.autoSize) {
MM.removeEvent(window, 'resize', this.windowResize());
this.autoSize = false;
}
this.draw(); // draw calls enforceLimits
// (if you switch to getFrame, call enforceLimits first)
this.dispatchCallback('resized', this.dimensions);
return this;
},
// projecting points on and off screen
coordinatePoint: function(coord) {
// Return an x, y point on the map image for a given coordinate.
if (coord.zoom != this.coordinate.zoom) {
coord = coord.zoomTo(this.coordinate.zoom);
}
// distance from the center of the map
var point = new MM.Point(this.dimensions.x / 2, this.dimensions.y / 2);
point.x += this.tileSize.x * (coord.column - this.coordinate.column);
point.y += this.tileSize.y * (coord.row - this.coordinate.row);
return point;
},
// Get a `MM.Coordinate` from an `MM.Point` - returns a new tile-like object
// from a screen point.
pointCoordinate: function(point) {
// new point coordinate reflecting distance from map center, in tile widths
var coord = this.coordinate.copy();
coord.column += (point.x - this.dimensions.x / 2) / this.tileSize.x;
coord.row += (point.y - this.dimensions.y / 2) / this.tileSize.y;
return coord;
},
// Return an MM.Coordinate (row,col,zoom) for an MM.Location (lat,lon).
locationCoordinate: function(location) {
return this.projection.locationCoordinate(location);
},
// Return an MM.Location (lat,lon) for an MM.Coordinate (row,col,zoom).
coordinateLocation: function(coordinate) {
return this.projection.coordinateLocation(coordinate);
},
// Return an x, y point on the map image for a given geographical location.
locationPoint: function(location) {
return this.coordinatePoint(this.locationCoordinate(location));
},
// Return a geographical location on the map image for a given x, y point.
pointLocation: function(point) {
return this.coordinateLocation(this.pointCoordinate(point));
},
// inspecting
getExtent: function() {
return new MM.Extent(
this.pointLocation(new MM.Point(0, 0)),
this.pointLocation(this.dimensions)
);
},
extent: function(locations, precise) {
if (locations) {
return this.setExtent(locations, precise);
} else {
return this.getExtent();
}
},
// Get the current centerpoint of the map, returning a `Location`
getCenter: function() {
return this.projection.coordinateLocation(this.coordinate);
},
center: function(location) {
if (location) {
return this.setCenter(location);
} else {
return this.getCenter();
}
},
// Get the current zoom level of the map, returning a number
getZoom: function() {
return this.coordinate.zoom;
},
zoom: function(zoom) {
if (zoom !== undefined) {
return this.setZoom(zoom);
} else {
return this.getZoom();
}
},
// return a copy of the layers array
getLayers: function() {
return this.layers.slice();
},
// return the first layer with given name
getLayer: function(name) {
for (var i = 0; i < this.layers.length; i++) {
if (name == this.layers[i].name)
return this.layers[i];
}
},
// return the layer at the given index
getLayerAt: function(index) {
return this.layers[index];
},
// put the given layer on top of all the others
// Since this is called for the first layer, which is by definition
// added before the map has a valid `coordinate`, we request
// a redraw only if the map has a center coordinate.
addLayer: function(layer) {
this.layers.push(layer);
this.parent.appendChild(layer.parent);
layer.map = this; // TODO: remove map property from MM.Layer?
if (this.coordinate) {
MM.getFrame(this.getRedraw());
}
return this;
},
// find the given layer and remove it
removeLayer: function(layer) {
for (var i = 0; i < this.layers.length; i++) {
if (layer == this.layers[i] || layer == this.layers[i].name) {
this.removeLayerAt(i);
break;
}
}
return this;
},
// replace the current layer at the given index with the given layer
setLayerAt: function(index, layer) {
if (index < 0 || index >= this.layers.length) {
throw new Error('invalid index in setLayerAt(): ' + index);
}
if (this.layers[index] != layer) {
// clear existing layer at this index
if (index < this.layers.length) {
var other = this.layers[index];
this.parent.insertBefore(layer.parent, other.parent);
other.destroy();
} else {
// Or if this will be the last layer, it can be simply appended
this.parent.appendChild(layer.parent);
}
this.layers[index] = layer;
layer.map = this; // TODO: remove map property from MM.Layer
MM.getFrame(this.getRedraw());
}
return this;
},
// put the given layer at the given index, moving others if necessary
insertLayerAt: function(index, layer) {
if (index < 0 || index > this.layers.length) {
throw new Error('invalid index in insertLayerAt(): ' + index);
}
if (index == this.layers.length) {
// it just gets tacked on to the end
this.layers.push(layer);
this.parent.appendChild(layer.parent);
} else {
// it needs to get slipped in amongst the others
var other = this.layers[index];
this.parent.insertBefore(layer.parent, other.parent);
this.layers.splice(index, 0, layer);
}
layer.map = this; // TODO: remove map property from MM.Layer
MM.getFrame(this.getRedraw());
return this;
},
// remove the layer at the given index, call .destroy() on the layer
removeLayerAt: function(index) {
if (index < 0 || index >= this.layers.length) {
throw new Error('invalid index in removeLayer(): ' + index);
}
// gone baby gone.
var old = this.layers[index];
this.layers.splice(index, 1);
old.destroy();
return this;
},
// switch the stacking order of two layers, by index
swapLayersAt: function(i, j) {
if (i < 0 || i >= this.layers.length || j < 0 || j >= this.layers.length) {
throw new Error('invalid index in swapLayersAt(): ' + index);
}
var layer1 = this.layers[i],
layer2 = this.layers[j],
dummy = document.createElement('div');
// kick layer2 out, replace it with the dummy.
this.parent.replaceChild(dummy, layer2.parent);
// put layer2 back in and kick layer1 out
this.parent.replaceChild(layer2.parent, layer1.parent);
// put layer1 back in and ditch the dummy
this.parent.replaceChild(layer1.parent, dummy);
// now do it to the layers array
this.layers[i] = layer2;
this.layers[j] = layer1;
return this;
},
// Enable and disable layers.
// Disabled layers are not displayed, are not drawn, and do not request
// tiles. They do maintain their layer index on the map.
enableLayer: function(name) {
var l = this.getLayer(name);
if (l) l.enable();
return this;
},
enableLayerAt: function(index) {
var l = this.getLayerAt(index);
if (l) l.enable();
return this;
},
disableLayer: function(name) {
var l = this.getLayer(name);
if (l) l.disable();
return this;
},
disableLayerAt: function(index) {
var l = this.getLayerAt(index);
if (l) l.disable();
return this;
},
// limits
enforceZoomLimits: function(coord) {
var limits = this.coordLimits;
if (limits) {
// clamp zoom level:
var minZoom = limits[0].zoom;
var maxZoom = limits[1].zoom;
if (coord.zoom < minZoom) {
coord = coord.zoomTo(minZoom);
}
else if (coord.zoom > maxZoom) {
coord = coord.zoomTo(maxZoom);
}
}
return coord;
},
enforcePanLimits: function(coord) {
if (this.coordLimits) {
coord = coord.copy();
// clamp pan:
var topLeftLimit = this.coordLimits[0].zoomTo(coord.zoom);
var bottomRightLimit = this.coordLimits[1].zoomTo(coord.zoom);
var currentTopLeft = this.pointCoordinate(new MM.Point(0, 0))
.zoomTo(coord.zoom);
var currentBottomRight = this.pointCoordinate(this.dimensions)
.zoomTo(coord.zoom);
// this handles infinite limits:
// (Infinity - Infinity) is Nan
// NaN is never less than anything
if (bottomRightLimit.row - topLeftLimit.row <
currentBottomRight.row - currentTopLeft.row) {
// if the limit is smaller than the current view center it
coord.row = (bottomRightLimit.row + topLeftLimit.row) / 2;
} else {
if (currentTopLeft.row < topLeftLimit.row) {
coord.row += topLeftLimit.row - currentTopLeft.row;
} else if (currentBottomRight.row > bottomRightLimit.row) {
coord.row -= currentBottomRight.row - bottomRightLimit.row;
}
}
if (bottomRightLimit.column - topLeftLimit.column <
currentBottomRight.column - currentTopLeft.column) {
// if the limit is smaller than the current view, center it
coord.column = (bottomRightLimit.column + topLeftLimit.column) / 2;
} else {
if (currentTopLeft.column < topLeftLimit.column) {
coord.column += topLeftLimit.column - currentTopLeft.column;
} else if (currentBottomRight.column > bottomRightLimit.column) {
coord.column -= currentBottomRight.column - bottomRightLimit.column;
}
}
}
return coord;
},
// Prevent accidentally navigating outside the `coordLimits` of the map.
enforceLimits: function(coord) {
return this.enforcePanLimits(this.enforceZoomLimits(coord));
},
// rendering
// Redraw the tiles on the map, reusing existing tiles.
draw: function() {
// make sure we're not too far in or out:
this.coordinate = this.enforceLimits(this.coordinate);
// if we don't have dimensions, check the parent size
if (this.dimensions.x <= 0 || this.dimensions.y <= 0) {
if (this.autoSize) {
// maybe the parent size has changed?
var w = this.parent.offsetWidth,
h = this.parent.offsetHeight;
this.dimensions = new MM.Point(w,h);
if (w <= 0 || h <= 0) {
return;
}
} else {
// the issue can only be corrected with setSize
return;
}
}
// draw layers one by one
for(var i = 0; i < this.layers.length; i++) {
this.layers[i].draw();
}
this.dispatchCallback('drawn');
},
_redrawTimer: undefined,
requestRedraw: function() {
// we'll always draw within 1 second of this request,
// sometimes faster if there's already a pending redraw
// this is used when a new tile arrives so that we clear
// any parent/child tiles that were only being displayed
// until the tile loads at the right zoom level
if (!this._redrawTimer) {
this._redrawTimer = setTimeout(this.getRedraw(), 1000);
}
},
_redraw: null,
getRedraw: function() {
// let's only create this closure once...
if (!this._redraw) {
var theMap = this;
this._redraw = function() {
theMap.draw();
theMap._redrawTimer = 0;
};
}
return this._redraw;
},
// Attempts to destroy all attachment a map has to a page
// and clear its memory usage.
destroy: function() {
for (var j = 0; j < this.layers.length; j++) {
this.layers[j].destroy();
}
this.layers = [];
this.projection = null;
for (var i = 0; i < this.eventHandlers.length; i++) {
this.eventHandlers[i].remove();
}
if (this.autoSize) {
MM.removeEvent(window, 'resize', this.windowResize());
}
}
};
// Instance of a map intended for drawing to a div.
//
// * `parent` (required DOM element)
// Can also be an ID of a DOM element
// * `provider` (required MM.MapProvider or URL template)
// * `location` (required MM.Location)
// Location for map to show
// * `zoom` (required number)
MM.mapByCenterZoom = function(parent, layerish, location, zoom) {
var layer = MM.coerceLayer(layerish),
map = new MM.Map(parent, layer, false);
map.setCenterZoom(location, zoom).draw();
return map;
};
// Instance of a map intended for drawing to a div.
//
// * `parent` (required DOM element)
// Can also be an ID of a DOM element
// * `provider` (required MM.MapProvider or URL template)
// * `locationA` (required MM.Location)
// Location of one map corner
// * `locationB` (required MM.Location)
// Location of other map corner
MM.mapByExtent = function(parent, layerish, locationA, locationB) {
var layer = MM.coerceLayer(layerish),
map = new MM.Map(parent, layer, false);
map.setExtent([locationA, locationB]).draw();
return map;
};
if (typeof module !== 'undefined' && module.exports) {
module.exports = {
Point: MM.Point,
Projection: MM.Projection,
MercatorProjection: MM.MercatorProjection,
LinearProjection: MM.LinearProjection,
Transformation: MM.Transformation,
Location: MM.Location,
MapProvider: MM.MapProvider,
Template: MM.Template,
Coordinate: MM.Coordinate,
deriveTransformation: MM.deriveTransformation
};
}
})(MM);
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