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| goog.provide('ol.tilegrid.TileGrid');
goog.require('goog.array');
goog.require('goog.asserts');
goog.require('goog.object');
goog.require('ol');
goog.require('ol.Coordinate');
goog.require('ol.TileCoord');
goog.require('ol.TileRange');
goog.require('ol.array');
goog.require('ol.extent');
goog.require('ol.extent.Corner');
goog.require('ol.math');
goog.require('ol.proj');
goog.require('ol.proj.METERS_PER_UNIT');
goog.require('ol.proj.Projection');
goog.require('ol.proj.Units');
goog.require('ol.size');
goog.require('ol.tilecoord');
/**
* @classdesc
* Base class for setting the grid pattern for sources accessing tiled-image
* servers.
*
* @constructor
* @param {olx.tilegrid.TileGridOptions} options Tile grid options.
* @struct
* @api stable
*/
ol.tilegrid.TileGrid = function(options) {
/**
* @protected
* @type {number}
*/
this.minZoom = options.minZoom !== undefined ? options.minZoom : 0;
/**
* @private
* @type {!Array.<number>}
*/
this.resolutions_ = options.resolutions;
goog.asserts.assert(goog.array.isSorted(this.resolutions_, function(a, b) {
return b - a;
}, true), 'resolutions must be sorted in descending order');
/**
* @protected
* @type {number}
*/
this.maxZoom = this.resolutions_.length - 1;
/**
* @private
* @type {ol.Coordinate}
*/
this.origin_ = options.origin !== undefined ? options.origin : null;
/**
* @private
* @type {Array.<ol.Coordinate>}
*/
this.origins_ = null;
if (options.origins !== undefined) {
this.origins_ = options.origins;
goog.asserts.assert(this.origins_.length == this.resolutions_.length,
'number of origins and resolutions must be equal');
}
var extent = options.extent;
if (extent !== undefined &&
!this.origin_ && !this.origins_) {
this.origin_ = ol.extent.getTopLeft(extent);
}
goog.asserts.assert(
(!this.origin_ && this.origins_) ||
(this.origin_ && !this.origins_),
'either origin or origins must be configured, never both');
/**
* @private
* @type {Array.<number|ol.Size>}
*/
this.tileSizes_ = null;
if (options.tileSizes !== undefined) {
this.tileSizes_ = options.tileSizes;
goog.asserts.assert(this.tileSizes_.length == this.resolutions_.length,
'number of tileSizes and resolutions must be equal');
}
/**
* @private
* @type {number|ol.Size}
*/
this.tileSize_ = options.tileSize !== undefined ?
options.tileSize :
!this.tileSizes_ ? ol.DEFAULT_TILE_SIZE : null;
goog.asserts.assert(
(!this.tileSize_ && this.tileSizes_) ||
(this.tileSize_ && !this.tileSizes_),
'either tileSize or tileSizes must be configured, never both');
/**
* @private
* @type {ol.Extent}
*/
this.extent_ = extent !== undefined ? extent : null;
/**
* @private
* @type {Array.<ol.TileRange>}
*/
this.fullTileRanges_ = null;
if (options.sizes !== undefined) {
goog.asserts.assert(options.sizes.length == this.resolutions_.length,
'number of sizes and resolutions must be equal');
this.fullTileRanges_ = options.sizes.map(function(size, z) {
goog.asserts.assert(size[0] !== 0, 'width must not be 0');
goog.asserts.assert(size[1] !== 0, 'height must not be 0');
var tileRange = new ol.TileRange(
Math.min(0, size[0]), Math.max(size[0] - 1, -1),
Math.min(0, size[1]), Math.max(size[1] - 1, -1));
if (this.minZoom <= z && z <= this.maxZoom && extent !== undefined) {
goog.asserts.assert(tileRange.containsTileRange(
this.getTileRangeForExtentAndZ(extent, z)),
'extent tile range must not exceed tilegrid width and height');
}
return tileRange;
}, this);
} else if (extent) {
this.calculateTileRanges_(extent);
}
/**
* @private
* @type {ol.Size}
*/
this.tmpSize_ = [0, 0];
};
/**
* @private
* @type {ol.TileCoord}
*/
ol.tilegrid.TileGrid.tmpTileCoord_ = [0, 0, 0];
/**
* @param {ol.TileCoord} tileCoord Tile coordinate.
* @param {function(this: T, number, ol.TileRange): boolean} callback Callback.
* @param {T=} opt_this The object to use as `this` in `callback`.
* @param {ol.TileRange=} opt_tileRange Temporary ol.TileRange object.
* @param {ol.Extent=} opt_extent Temporary ol.Extent object.
* @return {boolean} Callback succeeded.
* @template T
*/
ol.tilegrid.TileGrid.prototype.forEachTileCoordParentTileRange =
function(tileCoord, callback, opt_this, opt_tileRange, opt_extent) {
var tileCoordExtent = this.getTileCoordExtent(tileCoord, opt_extent);
var z = tileCoord[0] - 1;
while (z >= this.minZoom) {
Iif (callback.call(opt_this, z,
this.getTileRangeForExtentAndZ(tileCoordExtent, z, opt_tileRange))) {
return true;
}
--z;
}
return false;
};
/**
* Get the extent for this tile grid, if it was configured.
* @return {ol.Extent} Extent.
*/
ol.tilegrid.TileGrid.prototype.getExtent = function() {
return this.extent_;
};
/**
* Get the maximum zoom level for the grid.
* @return {number} Max zoom.
* @api
*/
ol.tilegrid.TileGrid.prototype.getMaxZoom = function() {
return this.maxZoom;
};
/**
* Get the minimum zoom level for the grid.
* @return {number} Min zoom.
* @api
*/
ol.tilegrid.TileGrid.prototype.getMinZoom = function() {
return this.minZoom;
};
/**
* Get the origin for the grid at the given zoom level.
* @param {number} z Z.
* @return {ol.Coordinate} Origin.
* @api stable
*/
ol.tilegrid.TileGrid.prototype.getOrigin = function(z) {
if (this.origin_) {
return this.origin_;
} else {
goog.asserts.assert(this.origins_,
'origins cannot be null if origin is null');
goog.asserts.assert(this.minZoom <= z && z <= this.maxZoom,
'given z is not in allowed range (%s <= %s <= %s)',
this.minZoom, z, this.maxZoom);
return this.origins_[z];
}
};
/**
* Get the resolution for the given zoom level.
* @param {number} z Z.
* @return {number} Resolution.
* @api stable
*/
ol.tilegrid.TileGrid.prototype.getResolution = function(z) {
goog.asserts.assert(this.minZoom <= z && z <= this.maxZoom,
'given z is not in allowed range (%s <= %s <= %s)',
this.minZoom, z, this.maxZoom);
return this.resolutions_[z];
};
/**
* Get the list of resolutions for the tile grid.
* @return {Array.<number>} Resolutions.
* @api stable
*/
ol.tilegrid.TileGrid.prototype.getResolutions = function() {
return this.resolutions_;
};
/**
* @param {ol.TileCoord} tileCoord Tile coordinate.
* @param {ol.TileRange=} opt_tileRange Temporary ol.TileRange object.
* @param {ol.Extent=} opt_extent Temporary ol.Extent object.
* @return {ol.TileRange} Tile range.
*/
ol.tilegrid.TileGrid.prototype.getTileCoordChildTileRange =
function(tileCoord, opt_tileRange, opt_extent) {
if (tileCoord[0] < this.maxZoom) {
var tileCoordExtent = this.getTileCoordExtent(tileCoord, opt_extent);
return this.getTileRangeForExtentAndZ(
tileCoordExtent, tileCoord[0] + 1, opt_tileRange);
} else {
return null;
}
};
/**
* @param {number} z Z.
* @param {ol.TileRange} tileRange Tile range.
* @param {ol.Extent=} opt_extent Temporary ol.Extent object.
* @return {ol.Extent} Extent.
*/
ol.tilegrid.TileGrid.prototype.getTileRangeExtent =
function(z, tileRange, opt_extent) {
var origin = this.getOrigin(z);
var resolution = this.getResolution(z);
var tileSize = ol.size.toSize(this.getTileSize(z), this.tmpSize_);
var minX = origin[0] + tileRange.minX * tileSize[0] * resolution;
var maxX = origin[0] + (tileRange.maxX + 1) * tileSize[0] * resolution;
var minY = origin[1] + tileRange.minY * tileSize[1] * resolution;
var maxY = origin[1] + (tileRange.maxY + 1) * tileSize[1] * resolution;
return ol.extent.createOrUpdate(minX, minY, maxX, maxY, opt_extent);
};
/**
* @param {ol.Extent} extent Extent.
* @param {number} resolution Resolution.
* @param {ol.TileRange=} opt_tileRange Temporary tile range object.
* @return {ol.TileRange} Tile range.
*/
ol.tilegrid.TileGrid.prototype.getTileRangeForExtentAndResolution =
function(extent, resolution, opt_tileRange) {
var tileCoord = ol.tilegrid.TileGrid.tmpTileCoord_;
this.getTileCoordForXYAndResolution_(
extent[0], extent[1], resolution, false, tileCoord);
var minX = tileCoord[1];
var minY = tileCoord[2];
this.getTileCoordForXYAndResolution_(
extent[2], extent[3], resolution, true, tileCoord);
return ol.TileRange.createOrUpdate(
minX, tileCoord[1], minY, tileCoord[2], opt_tileRange);
};
/**
* @param {ol.Extent} extent Extent.
* @param {number} z Z.
* @param {ol.TileRange=} opt_tileRange Temporary tile range object.
* @return {ol.TileRange} Tile range.
*/
ol.tilegrid.TileGrid.prototype.getTileRangeForExtentAndZ =
function(extent, z, opt_tileRange) {
var resolution = this.getResolution(z);
return this.getTileRangeForExtentAndResolution(
extent, resolution, opt_tileRange);
};
/**
* @param {ol.TileCoord} tileCoord Tile coordinate.
* @return {ol.Coordinate} Tile center.
*/
ol.tilegrid.TileGrid.prototype.getTileCoordCenter = function(tileCoord) {
var origin = this.getOrigin(tileCoord[0]);
var resolution = this.getResolution(tileCoord[0]);
var tileSize = ol.size.toSize(this.getTileSize(tileCoord[0]), this.tmpSize_);
return [
origin[0] + (tileCoord[1] + 0.5) * tileSize[0] * resolution,
origin[1] + (tileCoord[2] + 0.5) * tileSize[1] * resolution
];
};
/**
* Get the extent of a tile coordinate.
*
* @param {ol.TileCoord} tileCoord Tile coordinate.
* @param {ol.Extent=} opt_extent Temporary extent object.
* @return {ol.Extent} Extent.
* @api
*/
ol.tilegrid.TileGrid.prototype.getTileCoordExtent =
function(tileCoord, opt_extent) {
var origin = this.getOrigin(tileCoord[0]);
var resolution = this.getResolution(tileCoord[0]);
var tileSize = ol.size.toSize(this.getTileSize(tileCoord[0]), this.tmpSize_);
var minX = origin[0] + tileCoord[1] * tileSize[0] * resolution;
var minY = origin[1] + tileCoord[2] * tileSize[1] * resolution;
var maxX = minX + tileSize[0] * resolution;
var maxY = minY + tileSize[1] * resolution;
return ol.extent.createOrUpdate(minX, minY, maxX, maxY, opt_extent);
};
/**
* Get the tile coordinate for the given map coordinate and resolution. This
* method considers that coordinates that intersect tile boundaries should be
* assigned the higher tile coordinate.
*
* @param {ol.Coordinate} coordinate Coordinate.
* @param {number} resolution Resolution.
* @param {ol.TileCoord=} opt_tileCoord Destination ol.TileCoord object.
* @return {ol.TileCoord} Tile coordinate.
* @api
*/
ol.tilegrid.TileGrid.prototype.getTileCoordForCoordAndResolution =
function(coordinate, resolution, opt_tileCoord) {
return this.getTileCoordForXYAndResolution_(
coordinate[0], coordinate[1], resolution, false, opt_tileCoord);
};
/**
* @param {number} x X.
* @param {number} y Y.
* @param {number} resolution Resolution.
* @param {boolean} reverseIntersectionPolicy Instead of letting edge
* intersections go to the higher tile coordinate, let edge intersections
* go to the lower tile coordinate.
* @param {ol.TileCoord=} opt_tileCoord Temporary ol.TileCoord object.
* @return {ol.TileCoord} Tile coordinate.
* @private
*/
ol.tilegrid.TileGrid.prototype.getTileCoordForXYAndResolution_ = function(
x, y, resolution, reverseIntersectionPolicy, opt_tileCoord) {
var z = this.getZForResolution(resolution);
var scale = resolution / this.getResolution(z);
var origin = this.getOrigin(z);
var tileSize = ol.size.toSize(this.getTileSize(z), this.tmpSize_);
var adjustX = reverseIntersectionPolicy ? 0.5 : 0;
var adjustY = reverseIntersectionPolicy ? 0 : 0.5;
var xFromOrigin = Math.floor((x - origin[0]) / resolution + adjustX);
var yFromOrigin = Math.floor((y - origin[1]) / resolution + adjustY);
var tileCoordX = scale * xFromOrigin / tileSize[0];
var tileCoordY = scale * yFromOrigin / tileSize[1];
if (reverseIntersectionPolicy) {
tileCoordX = Math.ceil(tileCoordX) - 1;
tileCoordY = Math.ceil(tileCoordY) - 1;
} else {
tileCoordX = Math.floor(tileCoordX);
tileCoordY = Math.floor(tileCoordY);
}
return ol.tilecoord.createOrUpdate(z, tileCoordX, tileCoordY, opt_tileCoord);
};
/**
* Get a tile coordinate given a map coordinate and zoom level.
* @param {ol.Coordinate} coordinate Coordinate.
* @param {number} z Zoom level.
* @param {ol.TileCoord=} opt_tileCoord Destination ol.TileCoord object.
* @return {ol.TileCoord} Tile coordinate.
* @api
*/
ol.tilegrid.TileGrid.prototype.getTileCoordForCoordAndZ =
function(coordinate, z, opt_tileCoord) {
var resolution = this.getResolution(z);
return this.getTileCoordForXYAndResolution_(
coordinate[0], coordinate[1], resolution, false, opt_tileCoord);
};
/**
* @param {ol.TileCoord} tileCoord Tile coordinate.
* @return {number} Tile resolution.
*/
ol.tilegrid.TileGrid.prototype.getTileCoordResolution = function(tileCoord) {
goog.asserts.assert(
this.minZoom <= tileCoord[0] && tileCoord[0] <= this.maxZoom,
'z of given tilecoord is not in allowed range (%s <= %s <= %s',
this.minZoom, tileCoord[0], this.maxZoom);
return this.resolutions_[tileCoord[0]];
};
/**
* Get the tile size for a zoom level. The type of the return value matches the
* `tileSize` or `tileSizes` that the tile grid was configured with. To always
* get an `ol.Size`, run the result through `ol.size.toSize()`.
* @param {number} z Z.
* @return {number|ol.Size} Tile size.
* @api stable
*/
ol.tilegrid.TileGrid.prototype.getTileSize = function(z) {
if (this.tileSize_) {
return this.tileSize_;
} else {
goog.asserts.assert(this.tileSizes_,
'tileSizes cannot be null if tileSize is null');
goog.asserts.assert(this.minZoom <= z && z <= this.maxZoom,
'z is not in allowed range (%s <= %s <= %s',
this.minZoom, z, this.maxZoom);
return this.tileSizes_[z];
}
};
/**
* @param {number} z Zoom level.
* @return {ol.TileRange} Extent tile range for the specified zoom level.
*/
ol.tilegrid.TileGrid.prototype.getFullTileRange = function(z) {
if (!this.fullTileRanges_) {
return null;
} else {
goog.asserts.assert(this.minZoom <= z && z <= this.maxZoom,
'z is not in allowed range (%s <= %s <= %s',
this.minZoom, z, this.maxZoom);
return this.fullTileRanges_[z];
}
};
/**
* @param {number} resolution Resolution.
* @return {number} Z.
*/
ol.tilegrid.TileGrid.prototype.getZForResolution = function(resolution) {
var z = ol.array.linearFindNearest(this.resolutions_, resolution, 0);
return ol.math.clamp(z, this.minZoom, this.maxZoom);
};
/**
* @param {!ol.Extent} extent Extent for this tile grid.
* @private
*/
ol.tilegrid.TileGrid.prototype.calculateTileRanges_ = function(extent) {
var length = this.resolutions_.length;
var fullTileRanges = new Array(length);
for (var z = this.minZoom; z < length; ++z) {
fullTileRanges[z] = this.getTileRangeForExtentAndZ(extent, z);
}
this.fullTileRanges_ = fullTileRanges;
};
/**
* @param {ol.proj.Projection} projection Projection.
* @return {ol.tilegrid.TileGrid} Default tile grid for the passed projection.
*/
ol.tilegrid.getForProjection = function(projection) {
var tileGrid = projection.getDefaultTileGrid();
if (!tileGrid) {
tileGrid = ol.tilegrid.createForProjection(projection);
projection.setDefaultTileGrid(tileGrid);
}
return tileGrid;
};
/**
* @param {ol.Extent} extent Extent.
* @param {number=} opt_maxZoom Maximum zoom level (default is
* ol.DEFAULT_MAX_ZOOM).
* @param {number|ol.Size=} opt_tileSize Tile size (default uses
* ol.DEFAULT_TILE_SIZE).
* @param {ol.extent.Corner=} opt_corner Extent corner (default is
* ol.extent.Corner.TOP_LEFT).
* @return {ol.tilegrid.TileGrid} TileGrid instance.
*/
ol.tilegrid.createForExtent =
function(extent, opt_maxZoom, opt_tileSize, opt_corner) {
var corner = opt_corner !== undefined ?
opt_corner : ol.extent.Corner.TOP_LEFT;
var resolutions = ol.tilegrid.resolutionsFromExtent(
extent, opt_maxZoom, opt_tileSize);
return new ol.tilegrid.TileGrid({
extent: extent,
origin: ol.extent.getCorner(extent, corner),
resolutions: resolutions,
tileSize: opt_tileSize
});
};
/**
* Creates a tile grid with a standard XYZ tiling scheme.
* @param {olx.tilegrid.XYZOptions=} opt_options Tile grid options.
* @return {ol.tilegrid.TileGrid} Tile grid instance.
* @api
*/
ol.tilegrid.createXYZ = function(opt_options) {
var options = /** @type {olx.tilegrid.TileGridOptions} */ ({});
goog.object.extend(options, opt_options !== undefined ?
opt_options : /** @type {olx.tilegrid.XYZOptions} */ ({}));
if (options.extent === undefined) {
options.extent = ol.proj.get('EPSG:3857').getExtent();
}
options.resolutions = ol.tilegrid.resolutionsFromExtent(
options.extent, options.maxZoom, options.tileSize);
delete options.maxZoom;
return new ol.tilegrid.TileGrid(options);
};
/**
* Create a resolutions array from an extent. A zoom factor of 2 is assumed.
* @param {ol.Extent} extent Extent.
* @param {number=} opt_maxZoom Maximum zoom level (default is
* ol.DEFAULT_MAX_ZOOM).
* @param {number|ol.Size=} opt_tileSize Tile size (default uses
* ol.DEFAULT_TILE_SIZE).
* @return {!Array.<number>} Resolutions array.
*/
ol.tilegrid.resolutionsFromExtent =
function(extent, opt_maxZoom, opt_tileSize) {
var maxZoom = opt_maxZoom !== undefined ?
opt_maxZoom : ol.DEFAULT_MAX_ZOOM;
var height = ol.extent.getHeight(extent);
var width = ol.extent.getWidth(extent);
var tileSize = ol.size.toSize(opt_tileSize !== undefined ?
opt_tileSize : ol.DEFAULT_TILE_SIZE);
var maxResolution = Math.max(
width / tileSize[0], height / tileSize[1]);
var length = maxZoom + 1;
var resolutions = new Array(length);
for (var z = 0; z < length; ++z) {
resolutions[z] = maxResolution / Math.pow(2, z);
}
return resolutions;
};
/**
* @param {ol.proj.ProjectionLike} projection Projection.
* @param {number=} opt_maxZoom Maximum zoom level (default is
* ol.DEFAULT_MAX_ZOOM).
* @param {ol.Size=} opt_tileSize Tile size (default uses ol.DEFAULT_TILE_SIZE).
* @param {ol.extent.Corner=} opt_corner Extent corner (default is
* ol.extent.Corner.BOTTOM_LEFT).
* @return {ol.tilegrid.TileGrid} TileGrid instance.
*/
ol.tilegrid.createForProjection =
function(projection, opt_maxZoom, opt_tileSize, opt_corner) {
var extent = ol.tilegrid.extentFromProjection(projection);
return ol.tilegrid.createForExtent(
extent, opt_maxZoom, opt_tileSize, opt_corner);
};
/**
* Generate a tile grid extent from a projection. If the projection has an
* extent, it is used. If not, a global extent is assumed.
* @param {ol.proj.ProjectionLike} projection Projection.
* @return {ol.Extent} Extent.
*/
ol.tilegrid.extentFromProjection = function(projection) {
projection = ol.proj.get(projection);
var extent = projection.getExtent();
if (!extent) {
var half = 180 * ol.proj.METERS_PER_UNIT[ol.proj.Units.DEGREES] /
projection.getMetersPerUnit();
extent = ol.extent.createOrUpdate(-half, -half, half, half);
}
return extent;
};
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