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Copy pathpolymaps.js
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2136 lines (1887 loc) · 57.2 KB
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if (!org) var org = {};
if (!org.polymaps) org.polymaps = {};
(function(po){
po.version = "2.2.0"; // semver.org
var zero = {x: 0, y: 0};
po.ns = {
svg: "http://www.w3.org/2000/svg",
xlink: "http://www.w3.org/1999/xlink"
};
function ns(name) {
var i = name.indexOf(":");
return i < 0 ? name : {
space: po.ns[name.substring(0, i)],
local: name.substring(i + 1)
};
}
po.id = (function() {
var id = 0;
return function() {
return ++id;
};
})();
po.svg = function(type) {
return document.createElementNS(po.ns.svg, type);
};
po.transform = function(a, b, c, d, e, f) {
var transform = {},
zoomDelta,
zoomFraction,
k;
if (!arguments.length) {
a = 1; c = 0; e = 0;
b = 0; d = 1; f = 0;
}
transform.zoomFraction = function(x) {
if (!arguments.length) return zoomFraction;
zoomFraction = x;
zoomDelta = Math.floor(zoomFraction + Math.log(Math.sqrt(a * a + b * b + c * c + d * d)) / Math.log(2));
k = Math.pow(2, -zoomDelta);
return transform;
};
transform.apply = function(x) {
var k0 = Math.pow(2, -x.zoom),
k1 = Math.pow(2, x.zoom - zoomDelta);
return {
column: (a * x.column * k0 + c * x.row * k0 + e) * k1,
row: (b * x.column * k0 + d * x.row * k0 + f) * k1,
zoom: x.zoom - zoomDelta
};
};
transform.unapply = function(x) {
var k0 = Math.pow(2, -x.zoom),
k1 = Math.pow(2, x.zoom + zoomDelta);
return {
column: (x.column * k0 * d - x.row * k0 * c - e * d + f * c) / (a * d - b * c) * k1,
row: (x.column * k0 * b - x.row * k0 * a - e * b + f * a) / (c * b - d * a) * k1,
zoom: x.zoom + zoomDelta
};
};
transform.toString = function() {
return "matrix(" + [a * k, b * k, c * k, d * k].join(" ") + " 0 0)";
};
return transform.zoomFraction(0);
};
po.cache = function(load, unload) {
var cache = {},
locks = {},
map = {},
head = null,
tail = null,
size = 64,
n = 0;
function remove(tile) {
n--;
if (unload) unload(tile);
delete map[tile.key];
if (tile.next) tile.next.prev = tile.prev;
else if (tail = tile.prev) tail.next = null;
if (tile.prev) tile.prev.next = tile.next;
else if (head = tile.next) head.prev = null;
}
function flush() {
for (var tile = tail; n > size; tile = tile.prev) {
if (!tile) break;
if (tile.lock) continue;
remove(tile);
}
}
cache.peek = function(c) {
return map[[c.zoom, c.column, c.row].join("/")];
};
cache.load = function(c, projection) {
var key = [c.zoom, c.column, c.row].join("/"),
tile = map[key];
if (tile) {
if (tile.prev) {
tile.prev.next = tile.next;
if (tile.next) tile.next.prev = tile.prev;
else tail = tile.prev;
tile.prev = null;
tile.next = head;
head.prev = tile;
head = tile;
}
tile.lock = 1;
locks[key] = tile;
return tile;
}
tile = {
key: key,
column: c.column,
row: c.row,
zoom: c.zoom,
next: head,
prev: null,
lock: 1
};
load.call(null, tile, projection);
locks[key] = map[key] = tile;
if (head) head.prev = tile;
else tail = tile;
head = tile;
n++;
return tile;
};
cache.unload = function(key) {
if (!(key in locks)) return false;
var tile = locks[key];
tile.lock = 0;
delete locks[key];
if (tile.request && tile.request.abort(false)) remove(tile);
return tile;
};
cache.locks = function() {
return locks;
};
cache.size = function(x) {
if (!arguments.length) return size;
size = x;
flush();
return cache;
};
cache.flush = function() {
flush();
return cache;
};
cache.clear = function() {
for (var key in map) {
var tile = map[key];
if (tile.request) tile.request.abort(false);
if (unload) unload(map[key]);
if (tile.lock) {
tile.lock = 0;
tile.element.parentNode.removeChild(tile.element);
}
}
locks = {};
map = {};
head = tail = null;
n = 0;
return cache;
};
return cache;
};
po.url = function(template) {
var hosts = [];
function format(c) {
var max = c.zoom < 0 ? 1 : 1 << c.zoom,
column = c.column % max;
if (column < 0) column += max;
return template.replace(/{(.)}/g, function(s, v) {
switch (v) {
case "S": return hosts[(Math.abs(c.zoom) + c.row + column) % hosts.length];
case "Z": return c.zoom;
case "X": return column;
case "Y": return c.row;
case "B": {
var nw = po.map.coordinateLocation({row: c.row, column: column, zoom: c.zoom}),
se = po.map.coordinateLocation({row: c.row + 1, column: column + 1, zoom: c.zoom}),
pn = Math.ceil(Math.log(c.zoom) / Math.LN2);
return se.lat.toFixed(pn)
+ "," + nw.lon.toFixed(pn)
+ "," + nw.lat.toFixed(pn)
+ "," + se.lon.toFixed(pn);
}
}
return v;
});
}
format.template = function(x) {
if (!arguments.length) return template;
template = x;
return format;
};
format.hosts = function(x) {
if (!arguments.length) return hosts;
hosts = x;
return format;
};
return format;
};
po.dispatch = function(that) {
var types = {};
that.on = function(type, handler) {
var listeners = types[type] || (types[type] = []);
for (var i = 0; i < listeners.length; i++) {
if (listeners[i].handler == handler) return that; // already registered
}
listeners.push({handler: handler, on: true});
return that;
};
that.off = function(type, handler) {
var listeners = types[type];
if (listeners) for (var i = 0; i < listeners.length; i++) {
var l = listeners[i];
if (l.handler == handler) {
l.on = false;
listeners.splice(i, 1);
break;
}
}
return that;
};
return function(event) {
var listeners = types[event.type];
if (!listeners) return;
listeners = listeners.slice(); // defensive copy
for (var i = 0; i < listeners.length; i++) {
var l = listeners[i];
if (l.on) l.handler.call(that, event);
}
};
};
po.queue = (function() {
var queued = [], active = 0, size = 6;
function process() {
if ((active >= size) || !queued.length) return;
active++;
queued.pop()();
}
function dequeue(send) {
for (var i = 0; i < queued.length; i++) {
if (queued[i] == send) {
queued.splice(i, 1);
return true;
}
}
return false;
}
function request(url, callback, mimeType) {
var req;
function send() {
req = new XMLHttpRequest();
if (mimeType && req.overrideMimeType) {
req.overrideMimeType(mimeType);
}
req.open("GET", url, true);
req.onreadystatechange = function(e) {
if (req.readyState == 4) {
active--;
if (req.status < 300) callback(req);
process();
}
};
req.send(null);
}
function abort(hard) {
if (dequeue(send)) return true;
if (hard && req) { req.abort(); return true; }
return false;
}
queued.push(send);
process();
return {abort: abort};
}
function text(url, callback, mimeType) {
return request(url, function(req) {
if (req.responseText) callback(req.responseText);
}, mimeType);
}
/*
* We the override MIME type here so that you can load local files; some
* browsers don't assign a proper MIME type for local files.
*/
function json(url, callback) {
return request(url, function(req) {
if (req.responseText) callback(JSON.parse(req.responseText));
}, "application/json");
}
function xml(url, callback) {
return request(url, function(req) {
if (req.responseXML) callback(req.responseXML);
}, "application/xml");
}
function image(image, src, callback) {
var img;
function send() {
img = document.createElement("img");
img.onerror = function() {
active--;
process();
};
img.onload = function() {
active--;
callback(img);
process();
};
img.src = src;
image.setAttributeNS(po.ns.xlink, "href", src);
}
function abort(hard) {
if (dequeue(send)) return true;
if (hard && img) { img.src = "about:"; return true; } // cancels request
return false;
}
queued.push(send);
process();
return {abort: abort};
}
return {text: text, xml: xml, json: json, image: image};
})();
po.map = function() {
var map = {},
container,
size,
sizeActual = zero,
sizeRadius = zero, // sizeActual / 2
tileSize = {x: 256, y: 256},
center = {lat: 37.76487, lon: -122.41948},
zoom = 12,
zoomFraction = 0,
zoomFactor = 1, // Math.pow(2, zoomFraction)
zoomRange = [1, 18],
angle = 0,
angleCos = 1, // Math.cos(angle)
angleSin = 0, // Math.sin(angle)
angleCosi = 1, // Math.cos(-angle)
angleSini = 0, // Math.sin(-angle)
ymin = -180, // lat2y(centerRange[0].lat)
ymax = 180; // lat2y(centerRange[1].lat)
var centerRange = [
{lat: y2lat(ymin), lon: -Infinity},
{lat: y2lat(ymax), lon: Infinity}
];
map.locationCoordinate = function(l) {
var c = po.map.locationCoordinate(l),
k = Math.pow(2, zoom);
c.column *= k;
c.row *= k;
c.zoom += zoom;
return c;
};
map.coordinateLocation = po.map.coordinateLocation;
map.coordinatePoint = function(tileCenter, c) {
var kc = Math.pow(2, zoom - c.zoom),
kt = Math.pow(2, zoom - tileCenter.zoom),
dx = (c.column * kc - tileCenter.column * kt) * tileSize.x * zoomFactor,
dy = (c.row * kc - tileCenter.row * kt) * tileSize.y * zoomFactor;
return {
x: sizeRadius.x + angleCos * dx - angleSin * dy,
y: sizeRadius.y + angleSin * dx + angleCos * dy
};
};
map.pointCoordinate = function(tileCenter, p) {
var kt = Math.pow(2, zoom - tileCenter.zoom),
dx = (p.x - sizeRadius.x) / zoomFactor,
dy = (p.y - sizeRadius.y) / zoomFactor;
return {
column: tileCenter.column * kt + (angleCosi * dx - angleSini * dy) / tileSize.x,
row: tileCenter.row * kt + (angleSini * dx + angleCosi * dy) / tileSize.y,
zoom: zoom
};
};
map.locationPoint = function(l) {
var k = Math.pow(2, zoom + zoomFraction - 3) / 45,
dx = (l.lon - center.lon) * k * tileSize.x,
dy = (lat2y(center.lat) - lat2y(l.lat)) * k * tileSize.y;
return {
x: sizeRadius.x + angleCos * dx - angleSin * dy,
y: sizeRadius.y + angleSin * dx + angleCos * dy
};
};
map.pointLocation = function(p) {
var k = 45 / Math.pow(2, zoom + zoomFraction - 3),
dx = (p.x - sizeRadius.x) * k,
dy = (p.y - sizeRadius.y) * k;
return {
lon: center.lon + (angleCosi * dx - angleSini * dy) / tileSize.x,
lat: y2lat(lat2y(center.lat) - (angleSini * dx + angleCosi * dy) / tileSize.y)
};
};
function rezoom() {
if (zoomRange) {
if (zoom < zoomRange[0]) zoom = zoomRange[0];
else if (zoom > zoomRange[1]) zoom = zoomRange[1];
}
zoomFraction = zoom - (zoom = Math.round(zoom));
zoomFactor = Math.pow(2, zoomFraction);
}
function recenter() {
if (!centerRange) return;
var k = 45 / Math.pow(2, zoom + zoomFraction - 3);
// constrain latitude
var y = Math.max(Math.abs(angleSin * sizeRadius.x + angleCos * sizeRadius.y),
Math.abs(angleSini * sizeRadius.x + angleCosi * sizeRadius.y)),
lat0 = y2lat(ymin - y * k / tileSize.y),
lat1 = y2lat(ymax + y * k / tileSize.y);
center.lat = Math.max(lat0, Math.min(lat1, center.lat));
// constrain longitude
var x = Math.max(Math.abs(angleSin * sizeRadius.y + angleCos * sizeRadius.x),
Math.abs(angleSini * sizeRadius.y + angleCosi * sizeRadius.x)),
lon0 = centerRange[0].lon - x * k / tileSize.x,
lon1 = centerRange[1].lon + x * k / tileSize.x;
center.lon = Math.max(lon0, Math.min(lon1, center.lon));
}
// a place to capture mouse events if no tiles exist
var rect = po.svg("rect");
rect.setAttribute("visibility", "hidden");
rect.setAttribute("pointer-events", "all");
map.container = function(x) {
if (!arguments.length) return container;
container = x;
container.setAttribute("class", "map");
container.appendChild(rect);
return map.resize(); // infer size
};
map.focusableParent = function() {
for (var p = container; p; p = p.parentNode) {
if (p.tabIndex >= 0) return p;
}
return window;
};
map.mouse = function(e) {
var point = (container.ownerSVGElement || container).createSVGPoint();
if ((bug44083 < 0) && (window.scrollX || window.scrollY)) {
var svg = document.body.appendChild(po.svg("svg"));
svg.style.position = "absolute";
svg.style.top = svg.style.left = "0px";
var ctm = svg.getScreenCTM();
bug44083 = !(ctm.f || ctm.e);
document.body.removeChild(svg);
}
if (bug44083) {
point.x = e.pageX;
point.y = e.pageY;
} else {
point.x = e.clientX;
point.y = e.clientY;
}
return point.matrixTransform(container.getScreenCTM().inverse());
};
map.size = function(x) {
if (!arguments.length) return sizeActual;
size = x;
return map.resize(); // size tiles
};
map.resize = function() {
if (!size) {
/*
* Firefox does not correctly report the dimensions of SVG elements.
* However, it does correctly report the size of the child rect!
*/
var e = container.ownerSVGElement || container;
if (e.offsetWidth == null) {
rect.setAttribute("width", "100%");
rect.setAttribute("height", "100%");
e = rect;
}
b = e.getClientRects()[0];
sizeActual = {x: b.width, y: b.height};
resizer.add(map);
} else {
sizeActual = size;
resizer.remove(map);
}
rect.setAttribute("width", sizeActual.x);
rect.setAttribute("height", sizeActual.y);
sizeRadius = {x: sizeActual.x / 2, y: sizeActual.y / 2};
recenter();
map.dispatch({type: "resize"});
return map;
};
map.tileSize = function(x) {
if (!arguments.length) return tileSize;
tileSize = x;
map.dispatch({type: "move"});
return map;
};
map.center = function(x) {
if (!arguments.length) return center;
center = x;
recenter();
map.dispatch({type: "move"});
return map;
};
map.panBy = function(x) {
var k = 45 / Math.pow(2, zoom + zoomFraction - 3),
dx = x.x * k,
dy = x.y * k;
return map.center({
lon: center.lon + (angleSini * dy - angleCosi * dx) / tileSize.x,
lat: y2lat(lat2y(center.lat) + (angleSini * dx + angleCosi * dy) / tileSize.y)
});
};
map.centerRange = function(x) {
if (!arguments.length) return centerRange;
centerRange = x;
if (centerRange) {
ymin = centerRange[0].lat > -90 ? lat2y(centerRange[0].lat) : -Infinity;
ymax = centerRange[0].lat < 90 ? lat2y(centerRange[1].lat) : Infinity;
} else {
ymin = -Infinity;
ymax = Infinity;
}
recenter();
map.dispatch({type: "move"});
return map;
};
map.zoom = function(x) {
if (!arguments.length) return zoom + zoomFraction;
zoom = x;
rezoom();
return map.center(center);
};
map.zoomBy = function(z, x0, l) {
if (arguments.length < 2) return map.zoom(zoom + zoomFraction + z);
// compute the location of x0
if (arguments.length < 3) l = map.pointLocation(x0);
// update the zoom level
zoom = zoom + zoomFraction + z;
rezoom();
// compute the new point of the location
var x1 = map.locationPoint(l);
return map.panBy({x: x0.x - x1.x, y: x0.y - x1.y});
};
map.zoomRange = function(x) {
if (!arguments.length) return zoomRange;
zoomRange = x;
return map.zoom(zoom + zoomFraction);
};
map.extent = function(x) {
if (!arguments.length) return [
map.pointLocation({x: 0, y: sizeActual.y}),
map.pointLocation({x: sizeActual.x, y: 0})
];
// compute the extent in points, scale factor, and center
var bl = map.locationPoint(x[0]),
tr = map.locationPoint(x[1]),
k = Math.max((tr.x - bl.x) / sizeActual.x, (bl.y - tr.y) / sizeActual.y),
l = map.pointLocation({x: (bl.x + tr.x) / 2, y: (bl.y + tr.y) / 2});
// update the zoom level
zoom = zoom + zoomFraction - Math.log(k) / Math.log(2);
rezoom();
// set the new center
return map.center(l);
};
map.angle = function(x) {
if (!arguments.length) return angle;
angle = x;
angleCos = Math.cos(angle);
angleSin = Math.sin(angle);
angleCosi = Math.cos(-angle);
angleSini = Math.sin(-angle);
recenter();
map.dispatch({type: "move"});
return map;
};
map.add = function(x) {
x.map(map);
return map;
};
map.remove = function(x) {
x.map(null);
return map;
};
map.dispatch = po.dispatch(map);
return map;
};
function resizer(e) {
for (var i = 0; i < resizer.maps.length; i++) {
resizer.maps[i].resize();
}
}
resizer.maps = [];
resizer.add = function(map) {
for (var i = 0; i < resizer.maps.length; i++) {
if (resizer.maps[i] == map) return;
}
resizer.maps.push(map);
};
resizer.remove = function(map) {
for (var i = 0; i < resizer.maps.length; i++) {
if (resizer.maps[i] == map) {
resizer.maps.splice(i, 1);
return;
}
}
};
// Note: assumes single window (no frames, iframes, etc.)!
window.addEventListener("resize", resizer, false);
// See http://wiki.openstreetmap.org/wiki/Mercator
function y2lat(y) {
return 360 / Math.PI * Math.atan(Math.exp(y * Math.PI / 180)) - 90;
}
function lat2y(lat) {
return 180 / Math.PI * Math.log(Math.tan(Math.PI / 4 + lat * Math.PI / 360));
}
po.map.locationCoordinate = function(l) {
var k = 1 / 360;
return {
column: (l.lon + 180) * k,
row: (180 - lat2y(l.lat)) * k,
zoom: 0
};
};
po.map.coordinateLocation = function(c) {
var k = 45 / Math.pow(2, c.zoom - 3);
return {
lon: k * c.column - 180,
lat: y2lat(180 - k * c.row)
};
};
// https://bugs.webkit.org/show_bug.cgi?id=44083
var bug44083 = /WebKit/.test(navigator.userAgent) ? -1 : 0;
po.layer = function(load, unload) {
var layer = {},
cache = layer.cache = po.cache(load, unload).size(512),
tile = true,
visible = true,
zoom,
id,
map,
container = po.svg("g"),
transform,
levelZoom,
levels = {};
container.setAttribute("class", "layer");
for (var i = -4; i <= -1; i++) levels[i] = container.appendChild(po.svg("g"));
for (var i = 2; i >= 1; i--) levels[i] = container.appendChild(po.svg("g"));
levels[0] = container.appendChild(po.svg("g"));
function zoomIn(z) {
var end = levels[0].nextSibling;
for (; levelZoom < z; levelZoom++) {
// -4, -3, -2, -1, +2, +1, =0 // current order
// -3, -2, -1, +2, +1, =0, -4 // insertBefore(-4, end)
// -3, -2, -1, +1, =0, -4, +2 // insertBefore(+2, end)
// -3, -2, -1, =0, -4, +2, +1 // insertBefore(+1, end)
// -4, -3, -2, -1, +2, +1, =0 // relabel
container.insertBefore(levels[-4], end);
container.insertBefore(levels[2], end);
container.insertBefore(levels[1], end);
var t = levels[-4];
for (var dz = -4; dz < 2;) levels[dz] = levels[++dz];
levels[dz] = t;
}
}
function zoomOut(z) {
var end = levels[0].nextSibling;
for (; levelZoom > z; levelZoom--) {
// -4, -3, -2, -1, +2, +1, =0 // current order
// -4, -3, -2, +2, +1, =0, -1 // insertBefore(-1, end)
// +2, -4, -3, -2, +1, =0, -1 // insertBefore(+2, -4)
// -4, -3, -2, -1, +2, +1, =0 // relabel
container.insertBefore(levels[-1], end);
container.insertBefore(levels[2], levels[-4]);
var t = levels[2];
for (var dz = 2; dz > -4;) levels[dz] = levels[--dz];
levels[dz] = t;
}
}
function move() {
var map = layer.map(), // in case the layer is removed
mapZoom = map.zoom(),
mapZoomFraction = mapZoom - (mapZoom = Math.round(mapZoom)),
mapSize = map.size(),
mapAngle = map.angle(),
tileSize = map.tileSize(),
tileCenter = map.locationCoordinate(map.center());
// set the layer zoom levels
if (levelZoom != mapZoom) {
if (levelZoom < mapZoom) zoomIn(mapZoom);
else if (levelZoom > mapZoom) zoomOut(mapZoom);
else levelZoom = mapZoom;
for (var z = -4; z <= 2; z++) {
var l = levels[z];
l.setAttribute("class", "zoom" + (z < 0 ? "" : "+") + z + " zoom" + (mapZoom + z));
l.setAttribute("transform", "scale(" + Math.pow(2, -z) + ")");
}
}
// set the layer transform
container.setAttribute("transform",
"translate(" + (mapSize.x / 2) + "," + (mapSize.y / 2) + ")"
+ (mapAngle ? "rotate(" + mapAngle / Math.PI * 180 + ")" : "")
+ (mapZoomFraction ? "scale(" + Math.pow(2, mapZoomFraction) + ")" : "")
+ (transform ? transform.zoomFraction(mapZoomFraction) : ""));
// get the coordinates of the four corners
var c0 = map.pointCoordinate(tileCenter, zero),
c1 = map.pointCoordinate(tileCenter, {x: mapSize.x, y: 0}),
c2 = map.pointCoordinate(tileCenter, mapSize),
c3 = map.pointCoordinate(tileCenter, {x: 0, y: mapSize.y});
// round to pixel boundary to avoid anti-aliasing artifacts
if (!mapZoomFraction && !mapAngle && !transform) {
tileCenter.column = (Math.round(tileSize.x * tileCenter.column) + (mapSize.x & 1) / 2) / tileSize.x;
tileCenter.row = (Math.round(tileSize.y * tileCenter.row) + (mapSize.y & 1) / 2) / tileSize.y;
}
// layer-specific coordinate transform
if (transform) {
c0 = transform.unapply(c0);
c1 = transform.unapply(c1);
c2 = transform.unapply(c2);
c3 = transform.unapply(c3);
tileCenter = transform.unapply(tileCenter);
}
// layer-specific zoom transform
var tileLevel = zoom ? zoom(c0.zoom) - c0.zoom : 0;
if (tileLevel) {
var k = Math.pow(2, tileLevel);
c0.column *= k; c0.row *= k;
c1.column *= k; c1.row *= k;
c2.column *= k; c2.row *= k;
c3.column *= k; c3.row *= k;
c0.zoom = c1.zoom = c2.zoom = c3.zoom += tileLevel;
}
// tile-specific projection
function projection(c) {
var zoom = c.zoom,
max = zoom < 0 ? 1 : 1 << zoom,
column = c.column % max,
row = c.row;
if (column < 0) column += max;
return {
locationPoint: function(l) {
var c = po.map.locationCoordinate(l),
k = Math.pow(2, zoom - c.zoom);
return {
x: tileSize.x * (k * c.column - column),
y: tileSize.y * (k * c.row - row)
};
}
};
}
// record which tiles are visible
var oldLocks = cache.locks(), newLocks = {};
// reset the proxy counts
for (var key in oldLocks) {
oldLocks[key].proxyCount = 0;
}
// load the tiles!
if (visible && tileLevel > -5 && tileLevel < 3) {
var ymax = c0.zoom < 0 ? 1 : 1 << c0.zoom;
if (tile) {
scanTriangle(c0, c1, c2, 0, ymax, scanLine);
scanTriangle(c2, c3, c0, 0, ymax, scanLine);
} else {
var x = Math.floor((c0.column + c2.column) / 2),
y = Math.max(0, Math.min(ymax - 1, Math.floor((c1.row + c3.row) / 2))),
z = Math.min(4, c0.zoom);
x = x >> z << z;
y = y >> z << z;
scanLine(x, x + 1, y);
}
}
// scan-line conversion
function scanLine(x0, x1, y) {
var z = c0.zoom,
z0 = 2 - tileLevel,
z1 = 4 + tileLevel;
for (var x = x0; x < x1; x++) {
var t = cache.load({column: x, row: y, zoom: z}, projection);
if (!t.ready && !(t.key in newLocks)) {
t.proxyRefs = {};
var c, full, proxy;
// downsample high-resolution tiles
for (var dz = 1; dz <= z0; dz++) {
full = true;
for (var dy = 0, k = 1 << dz; dy <= k; dy++) {
for (var dx = 0; dx <= k; dx++) {
proxy = cache.peek(c = {
column: (x << dz) + dx,
row: (y << dz) + dy,
zoom: z + dz
});
if (proxy && proxy.ready) {
newLocks[proxy.key] = cache.load(c);
proxy.proxyCount++;
t.proxyRefs[proxy.key] = proxy;
} else {
full = false;
}
}
}
if (full) break;
}
// upsample low-resolution tiles
if (!full) {
for (var dz = 1; dz <= z1; dz++) {
proxy = cache.peek(c = {
column: x >> dz,
row: y >> dz,
zoom: z - dz
});
if (proxy && proxy.ready) {
newLocks[proxy.key] = cache.load(c);
proxy.proxyCount++;
t.proxyRefs[proxy.key] = proxy;
break;
}
}
}
}
newLocks[t.key] = t;
}
}
// position tiles
for (var key in newLocks) {
var t = newLocks[key],
k = Math.pow(2, t.level = t.zoom - tileCenter.zoom),
x = tileSize.x * (t.column - tileCenter.column * k),
y = tileSize.y * (t.row - tileCenter.row * k);
t.element.setAttribute("transform", "translate(" + x + "," + y + ")");
}
// remove tiles that are no longer visible
for (var key in oldLocks) {
if (!(key in newLocks)) {
var t = cache.unload(key);
t.element.parentNode.removeChild(t.element);
delete t.proxyRefs;
}
}
// append tiles that are now visible
for (var key in newLocks) {
var t = newLocks[key];
if (t.element.parentNode != levels[t.level]) {
levels[t.level].appendChild(t.element);
if (layer.show) layer.show(t);
}
}
// flush the cache, clearing no-longer-needed tiles
cache.flush();
}
// remove proxy tiles when tiles load
function cleanup(e) {
if (e.tile.proxyRefs) {
for (var proxyKey in e.tile.proxyRefs) {
var proxyTile = e.tile.proxyRefs[proxyKey];
if ((--proxyTile.proxyCount <= 0) && cache.unload(proxyKey)) {
proxyTile.element.parentNode.removeChild(proxyTile.element);
}
}
delete e.tile.proxyRefs;
}
}
layer.map = function(x) {
if (!arguments.length) return map;
if (map) {
if (map == x) {
container.parentNode.appendChild(container); // move to end
return layer;
}
map.off("move", move).off("resize", move);
container.parentNode.removeChild(container);
}
map = x;
if (map) {
map.container().appendChild(container);
if (layer.init) layer.init(container);
map.on("move", move).on("resize", move);
move();
}
return layer;
};
layer.container = function() {
return container;
};
layer.id = function(x) {
if (!arguments.length) return id;
id = x;
container.setAttribute("id", x);
return layer;
};
layer.visible = function(x) {
if (!arguments.length) return visible;
if (visible = x) container.removeAttribute("visibility")
else container.setAttribute("visibility", "hidden");
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