/**
* @name MarkerManager v3
* @version 1.0
* @copyright (c) 2007 Google Inc.
* @author Doug Ricket, Bjorn Brala (port to v3), others,
*
* @fileoverview Marker manager is an interface between the map and the user,
* designed to manage adding and removing many points when the viewport changes.
* <br /><br />
* <b>How it Works</b>:<br/>
* The MarkerManager places its markers onto a grid, similar to the map tiles.
* When the user moves the viewport, it computes which grid cells have
* entered or left the viewport, and shows or hides all the markers in those
* cells.
* (If the users scrolls the viewport beyond the markers that are loaded,
* no markers will be visible until the <code>EVENT_moveend</code>
* triggers an update.)
* In practical consequences, this allows 10,000 markers to be distributed over
* a large area, and as long as only 100-200 are visible in any given viewport,
* the user will see good performance corresponding to the 100 visible markers,
* rather than poor performance corresponding to the total 10,000 markers.
* Note that some code is optimized for speed over space,
* with the goal of accommodating thousands of markers.
*/
/*
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
/**
* @name MarkerManagerOptions
* @class This class represents optional arguments to the {@link MarkerManager}
* constructor.
* @property {Number} maxZoom Sets the maximum zoom level monitored by a
* marker manager. If not given, the manager assumes the maximum map zoom
* level. This value is also used when markers are added to the manager
* without the optional {@link maxZoom} parameter.
* @property {Number} borderPadding Specifies, in pixels, the extra padding
* outside the map's current viewport monitored by a manager. Markers that
* fall within this padding are added to the map, even if they are not fully
* visible.
* @property {Boolean} trackMarkers=false Indicates whether or not a marker
* manager should track markers' movements. If you wish to move managed
* markers using the {@link setPoint}/{@link setLatLng} methods,
* this option should be set to {@link true}.
*/
/**
* Creates a new MarkerManager that will show/hide markers on a map.
*
* Events:
* @event changed (Parameters: shown bounds, shown markers) Notify listeners when the state of what is displayed changes.
* @event loaded MarkerManager has succesfully been initialized.
*
* @constructor
* @param {Map} map The map to manage.
* @param {Object} opt_opts A container for optional arguments:
* {Number} maxZoom The maximum zoom level for which to create tiles.
* {Number} borderPadding The width in pixels beyond the map border,
* where markers should be display.
* {Boolean} trackMarkers Whether or not this manager should track marker
* movements.
*/
function MarkerManager(map, opt_opts) {
var me = this;
me.map_ = map;
me.mapZoom_ = map.getZoom();
me.projectionHelper_ = new ProjectionHelperOverlay(map);
google.maps.event.addListener(me.projectionHelper_, 'ready', function () {
me.projection_ = this.getProjection();
me.initialize(map, opt_opts);
});
}
MarkerManager.prototype.initialize = function (map, opt_opts) {
var me = this;
opt_opts = opt_opts || {};
me.tileSize_ = MarkerManager.DEFAULT_TILE_SIZE_;
var mapTypes = map.mapTypes;
// Find max zoom level
var mapMaxZoom = 1;
for (var sType in mapTypes ) {
if (typeof map.mapTypes.get(sType) === 'object' && typeof map.mapTypes.get(sType).maxZoom === 'number') {
var mapTypeMaxZoom = map.mapTypes.get(sType).maxZoom;
if (mapTypeMaxZoom > mapMaxZoom) {
mapMaxZoom = mapTypeMaxZoom;
}
}
}
me.maxZoom_ = opt_opts.maxZoom || 19;
me.trackMarkers_ = opt_opts.trackMarkers;
me.show_ = opt_opts.show || true;
var padding;
if (typeof opt_opts.borderPadding === 'number') {
padding = opt_opts.borderPadding;
} else {
padding = MarkerManager.DEFAULT_BORDER_PADDING_;
}
// The padding in pixels beyond the viewport, where we will pre-load markers.
me.swPadding_ = new google.maps.Size(-padding, padding);
me.nePadding_ = new google.maps.Size(padding, -padding);
me.borderPadding_ = padding;
me.gridWidth_ = {};
me.grid_ = {};
me.grid_[me.maxZoom_] = {};
me.numMarkers_ = {};
me.numMarkers_[me.maxZoom_] = 0;
google.maps.event.addListener(map, 'dragend', function () {
me.onMapMoveEnd_();
});
google.maps.event.addListener(map, 'zoom_changed', function () {
me.onMapMoveEnd_();
});
/**
* This closure provide easy access to the map.
* They are used as callbacks, not as methods.
* @param GMarker marker Marker to be removed from the map
* @private
*/
me.removeOverlay_ = function (marker) {
marker.setMap(null);
me.shownMarkers_--;
};
/**
* This closure provide easy access to the map.
* They are used as callbacks, not as methods.
* @param GMarker marker Marker to be added to the map
* @private
*/
me.addOverlay_ = function (marker) {
if (me.show_) {
marker.setMap(me.map_);
me.shownMarkers_++;
}
};
me.resetManager_();
me.shownMarkers_ = 0;
me.shownBounds_ = me.getMapGridBounds_();
google.maps.event.trigger(me, 'loaded');
};
/**
* Default tile size used for deviding the map into a grid.
*/
MarkerManager.DEFAULT_TILE_SIZE_ = 1024;
/*
* How much extra space to show around the map border so
* dragging doesn't result in an empty place.
*/
MarkerManager.DEFAULT_BORDER_PADDING_ = 100;
/**
* Default tilesize of single tile world.
*/
MarkerManager.MERCATOR_ZOOM_LEVEL_ZERO_RANGE = 256;
/**
* Initializes MarkerManager arrays for all zoom levels
* Called by constructor and by clearAllMarkers
*/
MarkerManager.prototype.resetManager_ = function () {
var mapWidth = MarkerManager.MERCATOR_ZOOM_LEVEL_ZERO_RANGE;
for (var zoom = 0; zoom <= this.maxZoom_; ++zoom) {
this.grid_[zoom] = {};
this.numMarkers_[zoom] = 0;
this.gridWidth_[zoom] = Math.ceil(mapWidth / this.tileSize_);
mapWidth <<= 1;
}
};
/**
* Removes all markers in the manager, and
* removes any visible markers from the map.
*/
MarkerManager.prototype.clearMarkers = function () {
this.processAll_(this.shownBounds_, this.removeOverlay_);
this.resetManager_();
};
/**
* Gets the tile coordinate for a given latlng point.
*
* @param {LatLng} latlng The geographical point.
* @param {Number} zoom The zoom level.
* @param {google.maps.Size} padding The padding used to shift the pixel coordinate.
* Used for expanding a bounds to include an extra padding
* of pixels surrounding the bounds.
* @return {GPoint} The point in tile coordinates.
*
*/
MarkerManager.prototype.getTilePoint_ = function (latlng, zoom, padding) {
var pixelPoint = this.projectionHelper_.LatLngToPixel(latlng, zoom);
var point = new google.maps.Point(
Math.floor((pixelPoint.x + padding.width) / this.tileSize_),
Math.floor((pixelPoint.y + padding.height) / this.tileSize_)
);
return point;
};
/**
* Finds the appropriate place to add the marker to the grid.
* Optimized for speed; does not actually add the marker to the map.
* Designed for batch-processing thousands of markers.
*
* @param {Marker} marker The marker to add.
* @param {Number} minZoom The minimum zoom for displaying the marker.
* @param {Number} maxZoom The maximum zoom for displaying the marker.
*/
MarkerManager.prototype.addMarkerBatch_ = function (marker, minZoom, maxZoom) {
var me = this;
var mPoint = marker.getPosition();
marker.MarkerManager_minZoom = minZoom;
// Tracking markers is expensive, so we do this only if the
// user explicitly requested it when creating marker manager.
if (this.trackMarkers_) {
google.maps.event.addListener(marker, 'changed', function (a, b, c) {
me.onMarkerMoved_(a, b, c);
});
}
var gridPoint = this.getTilePoint_(mPoint, maxZoom, new google.maps.Size(0, 0, 0, 0));
for (var zoom = maxZoom; zoom >= minZoom; zoom--) {
var cell = this.getGridCellCreate_(gridPoint.x, gridPoint.y, zoom);
cell.push(marker);
gridPoint.x = gridPoint.x >> 1;
gridPoint.y = gridPoint.y >> 1;
}
};
/**
* Returns whether or not the given point is visible in the shown bounds. This
* is a helper method that takes care of the corner case, when shownBounds have
* negative minX value.
*
* @param {Point} point a point on a grid.
* @return {Boolean} Whether or not the given point is visible in the currently
* shown bounds.
*/
MarkerManager.prototype.isGridPointVisible_ = function (point) {
var vertical = this.shownBounds_.minY <= point.y &&
point.y <= this.shownBounds_.maxY;
var minX = this.shownBounds_.minX;
var horizontal = minX <= point.x && point.x <= this.shownBounds_.maxX;
if (!horizontal && minX < 0) {
// Shifts the negative part of the rectangle. As point.x is always less
// than grid width, only test shifted minX .. 0 part of the shown bounds.
var width = this.gridWidth_[this.shownBounds_.z];
horizontal = minX + width <= point.x && point.x <= width - 1;
}
return vertical && horizontal;
};
/**
* Reacts to a notification from a marker that it has moved to a new location.
* It scans the grid all all zoom levels and moves the marker from the old grid
* location to a new grid location.
*
* @param {Marker} marker The marker that moved.
* @param {LatLng} oldPoint The old position of the marker.
* @param {LatLng} newPoint The new position of the marker.
*/
MarkerManager.prototype.onMarkerMoved_ = function (marker, oldPoint, newPoint) {
// NOTE: We do not know the minimum or maximum zoom the marker was
// added at, so we start at the absolute maximum. Whenever we successfully
// remove a marker at a given zoom, we add it at the new grid coordinates.
var zoom = this.maxZoom_;
var changed = false;
var oldGrid = this.getTilePoint_(oldPoint, zoom, new google.maps.Size(0, 0, 0, 0));
var newGrid = this.getTilePoint_(newPoint, zoom, new google.maps.Size(0, 0, 0, 0));
while (zoom >= 0 && (oldGrid.x !== newGrid.x || oldGrid.y !== newGrid.y)) {
var cell = this.getGridCellNoCreate_(oldGrid.x, oldGrid.y, zoom);
if (cell) {
if (this.removeFromArray_(cell, marker)) {
this.getGridCellCreate_(newGrid.x, newGrid.y, zoom).push(marker);
}
}
// For the current zoom we also need to update the map. Markers that no
// longer are visible are removed from the map. Markers that moved into
// the shown bounds are added to the map. This also lets us keep the count
// of visible markers up to date.
if (zoom === this.mapZoom_) {
if (this.isGridPointVisible_(oldGrid)) {
if (!this.isGridPointVisible_(newGrid)) {
this.removeOverlay_(marker);
changed = true;
}
} else {
if (this.isGridPointVisible_(newGrid)) {
this.addOverlay_(marker);
changed = true;
}
}
}
oldGrid.x = oldGrid.x >> 1;
oldGrid.y = oldGrid.y >> 1;
newGrid.x = newGrid.x >> 1;
newGrid.y = newGrid.y >> 1;
--zoom;
}
if (changed) {
this.notifyListeners_();
}
};
/**
* Removes marker from the manager and from the map
* (if it's currently visible).
* @param {GMarker} marker The marker to delete.
*/
MarkerManager.prototype.removeMarker = function (marker) {
var zoom = this.maxZoom_;
var changed = false;
var point = marker.getPosition();
var grid = this.getTilePoint_(point, zoom, new google.maps.Size(0, 0, 0, 0));
while (zoom >= 0) {
var cell = this.getGridCellNoCreate_(grid.x, grid.y, zoom);
if (cell) {
this.removeFromArray_(cell, marker);
}
// For the current zoom we also need to update the map. Markers that no
// longer are visible are removed from the map. This also lets us keep the count
// of visible markers up to date.
if (zoom === this.mapZoom_) {
if (this.isGridPointVisible_(grid)) {
this.removeOverlay_(marker);
changed = true;
}
}
grid.x = grid.x >> 1;
grid.y = grid.y >> 1;
--zoom;
}
if (changed) {
this.notifyListeners_();
}
this.numMarkers_[marker.MarkerManager_minZoom]--;
};
/**
* Add many markers at once.
* Does not actually update the map, just the internal grid.
*
* @param {Array of Marker} markers The markers to add.
* @param {Number} minZoom The minimum zoom level to display the markers.
* @param {Number} opt_maxZoom The maximum zoom level to display the markers.
*/
MarkerManager.prototype.addMarkers = function (markers, minZoom, opt_maxZoom) {
var maxZoom = this.getOptMaxZoom_(opt_maxZoom);
for (var i = markers.length - 1; i >= 0; i--) {
this.addMarkerBatch_(markers[i], minZoom, maxZoom);
}
this.numMarkers_[minZoom] += markers.length;
};
/**
* Returns the value of the optional maximum zoom. This method is defined so
* that we have just one place where optional maximum zoom is calculated.
*
* @param {Number} opt_maxZoom The optinal maximum zoom.
* @return The maximum zoom.
*/
MarkerManager.prototype.getOptMaxZoom_ = function (opt_maxZoom) {
return opt_maxZoom || this.maxZoom_;
};
/**
* Calculates the total number of markers potentially visible at a given
* zoom level.
*
* @param {Number} zoom The zoom level to check.
*/
MarkerManager.prototype.getMarkerCount = function (zoom) {
var total = 0;
for (var z = 0; z <= zoom; z++) {
total += this.numMarkers_[z];
}
return total;
};
/**
* Returns a marker given latitude, longitude and zoom. If the marker does not
* exist, the method will return a new marker. If a new marker is created,
* it will NOT be added to the manager.
*
* @param {Number} lat - the latitude of a marker.
* @param {Number} lng - the longitude of a marker.
* @param {Number} zoom - the zoom level
* @return {GMarker} marker - the marker found at lat and lng
*/
MarkerManager.prototype.getMarker = function (lat, lng, zoom) {
var mPoint = new google.maps.LatLng(lat, lng);
var gridPoint = this.getTilePoint_(mPoint, zoom, new google.maps.Size(0, 0, 0, 0));
var marker = new google.maps.Marker({position: mPoint});
var cellArray = this.getGridCellNoCreate_(gridPoint.x, gridPoint.y, zoom);
if (cellArray !== undefined) {
for (var i = 0; i < cellArray.length; i++)
{
if (lat === cellArray[i].getLatLng().lat() && lng === cellArray[i].getLatLng().lng()) {
marker = cellArray[i];
}
}
}
return marker;
};
/**
* Add a single marker to the map.
*
* @param {Marker} marker The marker to add.
* @param {Number} minZoom The minimum zoom level to display the marker.
* @param {Number} opt_maxZoom The maximum zoom level to display the marker.
*/
MarkerManager.prototype.addMarker = function (marker, minZoom, opt_maxZoom) {
var maxZoom = this.getOptMaxZoom_(opt_maxZoom);
this.addMarkerBatch_(marker, minZoom, maxZoom);
var gridPoint = this.getTilePoint_(marker.getPosition(), this.mapZoom_, new google.maps.Size(0, 0, 0, 0));
if (this.isGridPointVisible_(gridPoint) &&
minZoom <= this.shownBounds_.z &&
this.shownBounds_.z <= maxZoom) {
this.addOverlay_(marker);
this.notifyListeners_();
}
this.numMarkers_[minZoom]++;
};
/**
* Helper class to create a bounds of INT ranges.
* @param bounds Array.<Object.<string, number>> Bounds object.
* @constructor
*/
function GridBounds(bounds) {
// [sw, ne]
this.minX = Math.min(bounds[0].x, bounds[1].x);
this.maxX = Math.max(bounds[0].x, bounds[1].x);
this.minY = Math.min(bounds[0].y, bounds[1].y);
this.maxY = Math.max(bounds[0].y, bounds[1].y);
}
/**
* Returns true if this bounds equal the given bounds.
* @param {GridBounds} gridBounds GridBounds The bounds to test.
* @return {Boolean} This Bounds equals the given GridBounds.
*/
GridBounds.prototype.equals = function (gridBounds) {
if (this.maxX === gridBounds.maxX && this.maxY === gridBounds.maxY && this.minX === gridBounds.minX && this.minY === gridBounds.minY) {
return true;
} else {
return false;
}
};
/**
* Returns true if this bounds (inclusively) contains the given point.
* @param {Point} point The point to test.
* @return {Boolean} This Bounds contains the given Point.
*/
GridBounds.prototype.containsPoint = function (point) {
var outer = this;
return (outer.minX <= point.x && outer.maxX >= point.x && outer.minY <= point.y && outer.maxY >= point.y);
};
/**
* Get a cell in the grid, creating it first if necessary.
*
* Optimization candidate
*
* @param {Number} x The x coordinate of the cell.
* @param {Number} y The y coordinate of the cell.
* @param {Number} z The z coordinate of the cell.
* @return {Array} The cell in the array.
*/
MarkerManager.prototype.getGridCellCreate_ = function (x, y, z) {
var grid = this.grid_[z];
if (x < 0) {
x += this.gridWidth_[z];
}
var gridCol = grid[x];
if (!gridCol) {
gridCol = grid[x] = [];
return (gridCol[y] = []);
}
var gridCell = gridCol[y];
if (!gridCell) {
return (gridCol[y] = []);
}
return gridCell;
};
/**
* Get a cell in the grid, returning undefined if it does not exist.
*
* NOTE: Optimized for speed -- otherwise could combine with getGridCellCreate_.
*
* @param {Number} x The x coordinate of the cell.
* @param {Number} y The y coordinate of the cell.
* @param {Number} z The z coordinate of the cell.
* @return {Array} The cell in the array.
*/
MarkerManager.prototype.getGridCellNoCreate_ = function (x, y, z) {
var grid = this.grid_[z];
if (x < 0) {
x += this.gridWidth_[z];
}
var gridCol = grid[x];
return gridCol ? gridCol[y] : undefined;
};
/**
* Turns at geographical bounds into a grid-space bounds.
*
* @param {LatLngBounds} bounds The geographical bounds.
* @param {Number} zoom The zoom level of the bounds.
* @param {google.maps.Size} swPadding The padding in pixels to extend beyond the
* given bounds.
* @param {google.maps.Size} nePadding The padding in pixels to extend beyond the
* given bounds.
* @return {GridBounds} The bounds in grid space.
*/
MarkerManager.prototype.getGridBounds_ = function (bounds, zoom, swPadding, nePadding) {
zoom = Math.min(zoom, this.maxZoom_);
var bl = bounds.getSouthWest();
var tr = bounds.getNorthEast();
var sw = this.getTilePoint_(bl, zoom, swPadding);
var ne = this.getTilePoint_(tr, zoom, nePadding);
var gw = this.gridWidth_[zoom];
// Crossing the prime meridian requires correction of bounds.
if (tr.lng() < bl.lng() || ne.x < sw.x) {
sw.x -= gw;
}
if (ne.x - sw.x + 1 >= gw) {
// Computed grid bounds are larger than the world; truncate.
sw.x = 0;
ne.x = gw - 1;
}
var gridBounds = new GridBounds([sw, ne]);
gridBounds.z = zoom;
return gridBounds;
};
/**
* Gets the grid-space bounds for the current map viewport.
*
* @return {Bounds} The bounds in grid space.
*/
MarkerManager.prototype.getMapGridBounds_ = function () {
return this.getGridBounds_(this.map_.getBounds(), this.mapZoom_, this.swPadding_, this.nePadding_);
};
/**
* Event listener for map:movend.
* NOTE: Use a timeout so that the user is not blocked
* from moving the map.
*
* Removed this because a a lack of a scopy override/callback function on events.
*/
MarkerManager.prototype.onMapMoveEnd_ = function () {
this.objectSetTimeout_(this, this.updateMarkers_, 0);
};
/**
* Call a function or evaluate an expression after a specified number of
* milliseconds.
*
* Equivalent to the standard window.setTimeout function, but the given
* function executes as a method of this instance. So the function passed to
* objectSetTimeout can contain references to this.
* objectSetTimeout(this, function () { alert(this.x) }, 1000);
*
* @param {Object} object The target object.
* @param {Function} command The command to run.
* @param {Number} milliseconds The delay.
* @return {Boolean} Success.
*/
MarkerManager.prototype.objectSetTimeout_ = function (object, command, milliseconds) {
return window.setTimeout(function () {
command.call(object);
}, milliseconds);
};
/**
* Is this layer visible?
*
* Returns visibility setting
*
* @return {Boolean} Visible
*/
MarkerManager.prototype.visible = function () {
return this.show_ ? true : false;
};
/**
* Returns true if the manager is hidden.
* Otherwise returns false.
* @return {Boolean} Hidden
*/
MarkerManager.prototype.isHidden = function () {
return !this.show_;
};
/**
* Shows the manager if it's currently hidden.
*/
MarkerManager.prototype.show = function () {
this.show_ = true;
this.refresh();
};
/**
* Hides the manager if it's currently visible
*/
MarkerManager.prototype.hide = function () {
this.show_ = false;
this.refresh();
};
/**
* Toggles the visibility of the manager.
*/
MarkerManager.prototype.toggle = function () {
this.show_ = !this.show_;
this.refresh();
};
/**
* Refresh forces the marker-manager into a good state.
* <ol>
* <li>If never before initialized, shows all the markers.</li>
* <li>If previously initialized, removes and re-adds all markers.</li>
* </ol>
*/
MarkerManager.prototype.refresh = function () {
if (this.shownMarkers_ > 0) {
this.processAll_(this.shownBounds_, this.removeOverlay_);
}
// An extra check on this.show_ to increase performance (no need to processAll_)
if (this.show_) {
this.processAll_(this.shownBounds_, this.addOverlay_);
}
this.notifyListeners_();
};
/**
* After the viewport may have changed, add or remove markers as needed.
*/
MarkerManager.prototype.updateMarkers_ = function () {
this.mapZoom_ = this.map_.getZoom();
var newBounds = this.getMapGridBounds_();
// If the move does not include new grid sections,
// we have no work to do:
if (newBounds.equals(this.shownBounds_) && newBounds.z === this.shownBounds_.z) {
return;
}
if (newBounds.z !== this.shownBounds_.z) {
this.processAll_(this.shownBounds_, this.removeOverlay_);
if (this.show_) { // performance
this.processAll_(newBounds, this.addOverlay_);
}
} else {
// Remove markers:
this.rectangleDiff_(this.shownBounds_, newBounds, this.removeCellMarkers_);
// Add markers:
if (this.show_) { // performance
this.rectangleDiff_(newBounds, this.shownBounds_, this.addCellMarkers_);
}
}
this.shownBounds_ = newBounds;
this.notifyListeners_();
};
/**
* Notify listeners when the state of what is displayed changes.
*/
MarkerManager.prototype.notifyListeners_ = function () {
google.maps.event.trigger(this, 'changed', this.shownBounds_, this.shownMarkers_);
};
/**
* Process all markers in the bounds provided, using a callback.
*
* @param {Bounds} bounds The bounds in grid space.
* @param {Function} callback The function to call for each marker.
*/
MarkerManager.prototype.processAll_ = function (bounds, callback) {
for (var x = bounds.minX; x <= bounds.maxX; x++) {
for (var y = bounds.minY; y <= bounds.maxY; y++) {
this.processCellMarkers_(x, y, bounds.z, callback);
}
}
};
/**
* Process all markers in the grid cell, using a callback.
*
* @param {Number} x The x coordinate of the cell.
* @param {Number} y The y coordinate of the cell.
* @param {Number} z The z coordinate of the cell.
* @param {Function} callback The function to call for each marker.
*/
MarkerManager.prototype.processCellMarkers_ = function (x, y, z, callback) {
var cell = this.getGridCellNoCreate_(x, y, z);
if (cell) {
for (var i = cell.length - 1; i >= 0; i--) {
callback(cell[i]);
}
}
};
/**
* Remove all markers in a grid cell.
*
* @param {Number} x The x coordinate of the cell.
* @param {Number} y The y coordinate of the cell.
* @param {Number} z The z coordinate of the cell.
*/
MarkerManager.prototype.removeCellMarkers_ = function (x, y, z) {
this.processCellMarkers_(x, y, z, this.removeOverlay_);
};
/**
* Add all markers in a grid cell.
*
* @param {Number} x The x coordinate of the cell.
* @param {Number} y The y coordinate of the cell.
* @param {Number} z The z coordinate of the cell.
*/
MarkerManager.prototype.addCellMarkers_ = function (x, y, z) {
this.processCellMarkers_(x, y, z, this.addOverlay_);
};
/**
* Use the rectangleDiffCoords_ function to process all grid cells
* that are in bounds1 but not bounds2, using a callback, and using
* the current MarkerManager object as the instance.
*
* Pass the z parameter to the callback in addition to x and y.
*
* @param {Bounds} bounds1 The bounds of all points we may process.
* @param {Bounds} bounds2 The bounds of points to exclude.
* @param {Function} callback The callback function to call
* for each grid coordinate (x, y, z).
*/
MarkerManager.prototype.rectangleDiff_ = function (bounds1, bounds2, callback) {
var me = this;
me.rectangleDiffCoords_(bounds1, bounds2, function (x, y) {
callback.apply(me, [x, y, bounds1.z]);
});
};
/**
* Calls the function for all points in bounds1, not in bounds2
*
* @param {Bounds} bounds1 The bounds of all points we may process.
* @param {Bounds} bounds2 The bounds of points to exclude.
* @param {Function} callback The callback function to call
* for each grid coordinate.
*/
MarkerManager.prototype.rectangleDiffCoords_ = function (bounds1, bounds2, callback) {
var minX1 = bounds1.minX;
var minY1 = bounds1.minY;
var maxX1 = bounds1.maxX;
var maxY1 = bounds1.maxY;
var minX2 = bounds2.minX;
var minY2 = bounds2.minY;
var maxX2 = bounds2.maxX;
var maxY2 = bounds2.maxY;
var x, y;
for (x = minX1; x <= maxX1; x++) { // All x in R1
// All above:
for (y = minY1; y <= maxY1 && y < minY2; y++) { // y in R1 above R2
callback(x, y);
}
// All below:
for (y = Math.max(maxY2 + 1, minY1); // y in R1 below R2
y <= maxY1; y++) {
callback(x, y);
}
}
for (y = Math.max(minY1, minY2);
y <= Math.min(maxY1, maxY2); y++) { // All y in R2 and in R1
// Strictly left:
for (x = Math.min(maxX1 + 1, minX2) - 1;
x >= minX1; x--) { // x in R1 left of R2
callback(x, y);
}
// Strictly right:
for (x = Math.max(minX1, maxX2 + 1); // x in R1 right of R2
x <= maxX1; x++) {
callback(x, y);
}
}
};
/**
* Removes value from array. O(N).
*
* @param {Array} array The array to modify.
* @param {any} value The value to remove.
* @param {Boolean} opt_notype Flag to disable type checking in equality.
* @return {Number} The number of instances of value that were removed.
*/
MarkerManager.prototype.removeFromArray_ = function (array, value, opt_notype) {
var shift = 0;
for (var i = 0; i < array.length; ++i) {
if (array[i] === value || (opt_notype && array[i] === value)) {
array.splice(i--, 1);
shift++;
}
}
return shift;
};
/**
* Projection overlay helper. Helps in calculating
* that markers get into the right grid.
* @constructor
* @param {Map} map The map to manage.
**/
function ProjectionHelperOverlay(map) {
this.setMap(map);
var TILEFACTOR = 8;
var TILESIDE = 1 << TILEFACTOR;
var RADIUS = 7;
this._map = map;
this._zoom = -1;
this._X0 =
this._Y0 =
this._X1 =
this._Y1 = -1;
}
ProjectionHelperOverlay.prototype = new google.maps.OverlayView();
/**
* Helper function to convert Lng to X
* @private
* @param {float} lng
**/
ProjectionHelperOverlay.prototype.LngToX_ = function (lng) {
return (1 + lng / 180);
};
/**
* Helper function to convert Lat to Y
* @private
* @param {float} lat
**/
ProjectionHelperOverlay.prototype.LatToY_ = function (lat) {
var sinofphi = Math.sin(lat * Math.PI / 180);
return (1 - 0.5 / Math.PI * Math.log((1 + sinofphi) / (1 - sinofphi)));
};
/**
* Old school LatLngToPixel
* @param {LatLng} latlng google.maps.LatLng object
* @param {Number} zoom Zoom level
* @return {position} {x: pixelPositionX, y: pixelPositionY}
**/
ProjectionHelperOverlay.prototype.LatLngToPixel = function (latlng, zoom) {
var map = this._map;
var div = this.getProjection().fromLatLngToDivPixel(latlng);
var abs = {x: ~~(0.5 + this.LngToX_(latlng.lng()) * (2 << (zoom + 6))), y: ~~(0.5 + this.LatToY_(latlng.lat()) * (2 << (zoom + 6)))};
return abs;
};
/**
* Draw function only triggers a ready event for
* MarkerManager to know projection can proceed to
* initialize.
*/
ProjectionHelperOverlay.prototype.draw = function () {
if (!this.ready) {
this.ready = true;
google.maps.event.trigger(this, 'ready');
}
};
|
Download
