goog.provide('ol.Graticule');
goog.require('goog.asserts');
goog.require('goog.math');
goog.require('ol.extent');
goog.require('ol.geom.LineString');
goog.require('ol.geom.flat.geodesic');
goog.require('ol.proj');
goog.require('ol.render.EventType');
goog.require('ol.style.Stroke');
/**
* @constructor
* @param {olx.GraticuleOptions=} opt_options Options.
* @api
*/
ol.Graticule = function(opt_options) {
var options = goog.isDef(opt_options) ? opt_options : {};
/**
* @type {ol.Map}
* @private
*/
this.map_ = null;
/**
* @type {ol.proj.Projection}
* @private
*/
this.projection_ = null;
/**
* @type {number}
* @private
*/
this.maxLat_ = Infinity;
/**
* @type {number}
* @private
*/
this.maxLon_ = Infinity;
/**
* @type {number}
* @private
*/
this.minLat_ = -Infinity;
/**
* @type {number}
* @private
*/
this.minLon_ = -Infinity;
/**
* @type {number}
* @private
*/
this.targetSize_ = goog.isDef(options.targetSize) ?
options.targetSize : 100;
/**
* @type {number}
* @private
*/
this.maxLines_ = goog.isDef(options.maxLines) ? options.maxLines : 100;
goog.asserts.assert(this.maxLines_ > 0);
/**
* @type {Array.<ol.geom.LineString>}
* @private
*/
this.meridians_ = [];
/**
* @type {Array.<ol.geom.LineString>}
* @private
*/
this.parallels_ = [];
/**
* @type {ol.style.Stroke}
* @private
*/
this.strokeStyle_ = goog.isDef(options.strokeStyle) ?
options.strokeStyle : ol.Graticule.DEFAULT_STROKE_STYLE_;
/**
* @type {ol.TransformFunction|undefined}
* @private
*/
this.fromLonLatTransform_ = undefined;
/**
* @type {ol.TransformFunction|undefined}
* @private
*/
this.toLonLatTransform_ = undefined;
/**
* @type {ol.Coordinate}
* @private
*/
this.projectionCenterLonLat_ = null;
this.setMap(goog.isDef(options.map) ? options.map : null);
};
/**
* @type {ol.style.Stroke}
* @private
* @const
*/
ol.Graticule.DEFAULT_STROKE_STYLE_ = new ol.style.Stroke({
color: 'rgba(0,0,0,0.2)'
});
/**
* TODO can be configurable
* @type {Array.<number>}
* @private
*/
ol.Graticule.intervals_ = [90, 45, 30, 20, 10, 5, 2, 1, 0.5, 0.2, 0.1, 0.05,
0.01, 0.005, 0.002, 0.001];
/**
* @param {number} lon Longitude.
* @param {number} squaredTolerance Squared tolerance.
* @param {ol.Extent} extent Extent.
* @param {number} index Index.
* @return {number} Index.
* @private
*/
ol.Graticule.prototype.addMeridian_ =
function(lon, squaredTolerance, extent, index) {
var lineString = this.getMeridian_(lon, squaredTolerance, index);
if (ol.extent.intersects(lineString.getExtent(), extent)) {
this.meridians_[index++] = lineString;
}
return index;
};
/**
* @param {number} lat Latitude.
* @param {number} squaredTolerance Squared tolerance.
* @param {ol.Extent} extent Extent.
* @param {number} index Index.
* @return {number} Index.
* @private
*/
ol.Graticule.prototype.addParallel_ =
function(lat, squaredTolerance, extent, index) {
var lineString = this.getParallel_(lat, squaredTolerance, index);
if (ol.extent.intersects(lineString.getExtent(), extent)) {
this.parallels_[index++] = lineString;
}
return index;
};
/**
* @param {ol.Extent} extent Extent.
* @param {ol.Coordinate} center Center.
* @param {number} resolution Resolution.
* @param {number} squaredTolerance Squared tolerance.
* @private
*/
ol.Graticule.prototype.createGraticule_ =
function(extent, center, resolution, squaredTolerance) {
var interval = this.getInterval_(resolution);
if (interval == -1) {
this.meridians_.length = this.parallels_.length = 0;
return;
}
var centerLonLat = this.toLonLatTransform_(center);
var centerLon = centerLonLat[0];
var centerLat = centerLonLat[1];
var maxLines = this.maxLines_;
var cnt, idx, lat, lon;
// Create meridians
centerLon = Math.floor(centerLon / interval) * interval;
lon = goog.math.clamp(centerLon, this.minLon_, this.maxLon_);
idx = this.addMeridian_(lon, squaredTolerance, extent, 0);
cnt = 0;
while (lon != this.minLon_ && cnt++ < maxLines) {
lon = Math.max(lon - interval, this.minLon_);
idx = this.addMeridian_(lon, squaredTolerance, extent, idx);
}
lon = goog.math.clamp(centerLon, this.minLon_, this.maxLon_);
cnt = 0;
while (lon != this.maxLon_ && cnt++ < maxLines) {
lon = Math.min(lon + interval, this.maxLon_);
idx = this.addMeridian_(lon, squaredTolerance, extent, idx);
}
this.meridians_.length = idx;
// Create parallels
centerLat = Math.floor(centerLat / interval) * interval;
lat = goog.math.clamp(centerLat, this.minLat_, this.maxLat_);
idx = this.addParallel_(lat, squaredTolerance, extent, 0);
cnt = 0;
while (lat != this.minLat_ && cnt++ < maxLines) {
lat = Math.max(lat - interval, this.minLat_);
idx = this.addParallel_(lat, squaredTolerance, extent, idx);
}
lat = goog.math.clamp(centerLat, this.minLat_, this.maxLat_);
cnt = 0;
while (lat != this.maxLat_ && cnt++ < maxLines) {
lat = Math.min(lat + interval, this.maxLat_);
idx = this.addParallel_(lat, squaredTolerance, extent, idx);
}
this.parallels_.length = idx;
};
/**
* @param {number} resolution Resolution.
* @return {number} The interval in degrees.
* @private
*/
ol.Graticule.prototype.getInterval_ = function(resolution) {
var centerLon = this.projectionCenterLonLat_[0];
var centerLat = this.projectionCenterLonLat_[1];
var interval = -1;
var i, ii, delta, dist;
var target = Math.pow(this.targetSize_ * resolution, 2);
/** @type {Array.<number>} **/
var p1 = [];
/** @type {Array.<number>} **/
var p2 = [];
for (i = 0, ii = ol.Graticule.intervals_.length; i < ii; ++i) {
delta = ol.Graticule.intervals_[i] / 2;
p1[0] = centerLon - delta;
p1[1] = centerLat - delta;
p2[0] = centerLon + delta;
p2[1] = centerLat + delta;
this.fromLonLatTransform_(p1, p1);
this.fromLonLatTransform_(p2, p2);
dist = Math.pow(p2[0] - p1[0], 2) + Math.pow(p2[1] - p1[1], 2);
if (dist <= target) {
break;
}
interval = ol.Graticule.intervals_[i];
}
return interval;
};
/**
* @return {ol.Map} The map.
* @api
*/
ol.Graticule.prototype.getMap = function() {
return this.map_;
};
/**
* @param {number} lon Longitude.
* @param {number} squaredTolerance Squared tolerance.
* @return {ol.geom.LineString} The meridian line string.
* @param {number} index Index.
* @private
*/
ol.Graticule.prototype.getMeridian_ = function(lon, squaredTolerance, index) {
goog.asserts.assert(lon >= this.minLon_);
goog.asserts.assert(lon <= this.maxLon_);
var flatCoordinates = ol.geom.flat.geodesic.meridian(lon,
this.minLat_, this.maxLat_, this.projection_, squaredTolerance);
goog.asserts.assert(flatCoordinates.length > 0);
var lineString = goog.isDef(this.meridians_[index]) ?
this.meridians_[index] : new ol.geom.LineString(null);
lineString.setFlatCoordinates(ol.geom.GeometryLayout.XY, flatCoordinates);
return lineString;
};
/**
* @return {Array.<ol.geom.LineString>} The meridians.
* @api
*/
ol.Graticule.prototype.getMeridians = function() {
return this.meridians_;
};
/**
* @param {number} lat Latitude.
* @param {number} squaredTolerance Squared tolerance.
* @return {ol.geom.LineString} The parallel line string.
* @param {number} index Index.
* @private
*/
ol.Graticule.prototype.getParallel_ = function(lat, squaredTolerance, index) {
goog.asserts.assert(lat >= this.minLat_);
goog.asserts.assert(lat <= this.maxLat_);
var flatCoordinates = ol.geom.flat.geodesic.parallel(lat,
this.minLon_, this.maxLon_, this.projection_, squaredTolerance);
goog.asserts.assert(flatCoordinates.length > 0);
var lineString = goog.isDef(this.parallels_[index]) ?
this.parallels_[index] : new ol.geom.LineString(null);
lineString.setFlatCoordinates(ol.geom.GeometryLayout.XY, flatCoordinates);
return lineString;
};
/**
* @return {Array.<ol.geom.LineString>} The parallels.
* @api
*/
ol.Graticule.prototype.getParallels = function() {
return this.parallels_;
};
/**
* @param {ol.render.Event} e Event.
* @private
*/
ol.Graticule.prototype.handlePostCompose_ = function(e) {
var vectorContext = e.vectorContext;
var frameState = e.frameState;
var extent = frameState.extent;
var viewState = frameState.viewState;
var center = viewState.center;
var projection = viewState.projection;
var resolution = viewState.resolution;
var pixelRatio = frameState.pixelRatio;
var squaredTolerance =
resolution * resolution / (4 * pixelRatio * pixelRatio);
var updateProjectionInfo = goog.isNull(this.projection_) ||
!ol.proj.equivalent(this.projection_, projection);
if (updateProjectionInfo) {
this.updateProjectionInfo_(projection);
}
this.createGraticule_(extent, center, resolution, squaredTolerance);
// Draw the lines
vectorContext.setFillStrokeStyle(null, this.strokeStyle_);
var i, l, line;
for (i = 0, l = this.meridians_.length; i < l; ++i) {
line = this.meridians_[i];
vectorContext.drawLineStringGeometry(line, null);
}
for (i = 0, l = this.parallels_.length; i < l; ++i) {
line = this.parallels_[i];
vectorContext.drawLineStringGeometry(line, null);
}
};
/**
* @param {ol.proj.Projection} projection Projection.
* @private
*/
ol.Graticule.prototype.updateProjectionInfo_ = function(projection) {
goog.asserts.assert(!goog.isNull(projection));
var extent = projection.getExtent();
var worldExtent = projection.getWorldExtent();
var maxLat = worldExtent[3];
var maxLon = worldExtent[2];
var minLat = worldExtent[1];
var minLon = worldExtent[0];
goog.asserts.assert(!goog.isNull(extent));
goog.asserts.assert(goog.isDef(maxLat));
goog.asserts.assert(goog.isDef(maxLon));
goog.asserts.assert(goog.isDef(minLat));
goog.asserts.assert(goog.isDef(minLon));
this.maxLat_ = maxLat;
this.maxLon_ = maxLon;
this.minLat_ = minLat;
this.minLon_ = minLon;
var epsg4326Projection = ol.proj.get('EPSG:4326');
this.fromLonLatTransform_ = ol.proj.getTransform(
epsg4326Projection, projection);
this.toLonLatTransform_ = ol.proj.getTransform(
projection, epsg4326Projection);
this.projectionCenterLonLat_ = this.toLonLatTransform_(
ol.extent.getCenter(extent));
this.projection_ = projection;
};
/**
* @param {ol.Map} map Map.
* @api
*/
ol.Graticule.prototype.setMap = function(map) {
if (!goog.isNull(this.map_)) {
this.map_.un(ol.render.EventType.POSTCOMPOSE,
this.handlePostCompose_, this);
this.map_.render();
}
if (!goog.isNull(map)) {
map.on(ol.render.EventType.POSTCOMPOSE,
this.handlePostCompose_, this);
map.render();
}
this.map_ = map;
};
OpenLayers 3