Files
openlayers/src/ol/source/Tile.js
2019-07-30 16:50:01 +02:00

367 lines
10 KiB
JavaScript

/**
* @module ol/source/Tile
*/
import {abstract} from '../util.js';
import TileCache from '../TileCache.js';
import TileState from '../TileState.js';
import Event from '../events/Event.js';
import {equivalent} from '../proj.js';
import {toSize, scale as scaleSize} from '../size.js';
import Source from './Source.js';
import {getKeyZXY, withinExtentAndZ} from '../tilecoord.js';
import {wrapX, getForProjection as getTileGridForProjection} from '../tilegrid.js';
/**
* @typedef {Object} Options
* @property {import("./Source.js").AttributionLike} [attributions]
* @property {boolean} [attributionsCollapsible=true] Attributions are collapsible.
* @property {number} [cacheSize]
* @property {boolean} [opaque]
* @property {number} [tilePixelRatio]
* @property {import("../proj.js").ProjectionLike} [projection]
* @property {import("./State.js").default} [state]
* @property {import("../tilegrid/TileGrid.js").default} [tileGrid]
* @property {boolean} [wrapX=true]
* @property {number} [transition]
* @property {string} [key]
* @property {number} [zDirection=0]
*/
/**
* @classdesc
* Abstract base class; normally only used for creating subclasses and not
* instantiated in apps.
* Base class for sources providing images divided into a tile grid.
* @abstract
* @api
*/
class TileSource extends Source {
/**
* @param {Options} options SourceTile source options.
*/
constructor(options) {
super({
attributions: options.attributions,
attributionsCollapsible: options.attributionsCollapsible,
projection: options.projection,
state: options.state,
wrapX: options.wrapX
});
/**
* @private
* @type {boolean}
*/
this.opaque_ = options.opaque !== undefined ? options.opaque : false;
/**
* @private
* @type {number}
*/
this.tilePixelRatio_ = options.tilePixelRatio !== undefined ?
options.tilePixelRatio : 1;
/**
* @protected
* @type {import("../tilegrid/TileGrid.js").default}
*/
this.tileGrid = options.tileGrid !== undefined ? options.tileGrid : null;
let cacheSize = options.cacheSize;
if (cacheSize === undefined) {
const tileSize = [256, 256];
const tileGrid = options.tileGrid;
if (tileGrid) {
toSize(tileGrid.getTileSize(tileGrid.getMinZoom()), tileSize);
}
const canUseScreen = typeof screen !== 'undefined';
const width = canUseScreen ? (screen.availWidth || screen.width) : 1920;
const height = canUseScreen ? (screen.availHeight || screen.height) : 1080;
cacheSize = 4 * Math.ceil(width / tileSize[0]) * Math.ceil(height / tileSize[1]);
}
/**
* @protected
* @type {import("../TileCache.js").default}
*/
this.tileCache = new TileCache(cacheSize);
/**
* @protected
* @type {import("../size.js").Size}
*/
this.tmpSize = [0, 0];
/**
* @private
* @type {string}
*/
this.key_ = options.key || '';
/**
* @protected
* @type {import("../Tile.js").Options}
*/
this.tileOptions = {transition: options.transition};
/**
* zDirection hint, read by the renderer. Indicates which resolution should be used
* by a renderer if the views resolution does not match any resolution of the tile source.
* If 0, the nearest resolution will be used. If 1, the nearest lower resolution
* will be used. If -1, the nearest higher resolution will be used.
* @type {number}
*/
this.zDirection = options.zDirection ? options.zDirection : 0;
}
/**
* @return {boolean} Can expire cache.
*/
canExpireCache() {
return this.tileCache.canExpireCache();
}
/**
* @param {import("../proj/Projection.js").default} projection Projection.
* @param {!Object<string, import("../TileRange.js").default>} usedTiles Used tiles.
*/
expireCache(projection, usedTiles) {
const tileCache = this.getTileCacheForProjection(projection);
if (tileCache) {
tileCache.expireCache(usedTiles);
}
}
/**
* @param {import("../proj/Projection.js").default} projection Projection.
* @param {number} z Zoom level.
* @param {import("../TileRange.js").default} tileRange Tile range.
* @param {function(import("../Tile.js").default):(boolean|void)} callback Called with each
* loaded tile. If the callback returns `false`, the tile will not be
* considered loaded.
* @return {boolean} The tile range is fully covered with loaded tiles.
*/
forEachLoadedTile(projection, z, tileRange, callback) {
const tileCache = this.getTileCacheForProjection(projection);
if (!tileCache) {
return false;
}
let covered = true;
let tile, tileCoordKey, loaded;
for (let x = tileRange.minX; x <= tileRange.maxX; ++x) {
for (let y = tileRange.minY; y <= tileRange.maxY; ++y) {
tileCoordKey = getKeyZXY(z, x, y);
loaded = false;
if (tileCache.containsKey(tileCoordKey)) {
tile = /** @type {!import("../Tile.js").default} */ (tileCache.get(tileCoordKey));
loaded = tile.getState() === TileState.LOADED;
if (loaded) {
loaded = (callback(tile) !== false);
}
}
if (!loaded) {
covered = false;
}
}
}
return covered;
}
/**
* @param {import("../proj/Projection.js").default} projection Projection.
* @return {number} Gutter.
*/
getGutterForProjection(projection) {
return 0;
}
/**
* Return the key to be used for all tiles in the source.
* @return {string} The key for all tiles.
* @protected
*/
getKey() {
return this.key_;
}
/**
* Set the value to be used as the key for all tiles in the source.
* @param {string} key The key for tiles.
* @protected
*/
setKey(key) {
if (this.key_ !== key) {
this.key_ = key;
this.changed();
}
}
/**
* @param {import("../proj/Projection.js").default} projection Projection.
* @return {boolean} Opaque.
*/
getOpaque(projection) {
return this.opaque_;
}
/**
* @inheritDoc
*/
getResolutions() {
return this.tileGrid.getResolutions();
}
/**
* @abstract
* @param {number} z Tile coordinate z.
* @param {number} x Tile coordinate x.
* @param {number} y Tile coordinate y.
* @param {number} pixelRatio Pixel ratio.
* @param {import("../proj/Projection.js").default} projection Projection.
* @return {!import("../Tile.js").default} Tile.
*/
getTile(z, x, y, pixelRatio, projection) {
return abstract();
}
/**
* Return the tile grid of the tile source.
* @return {import("../tilegrid/TileGrid.js").default} Tile grid.
* @api
*/
getTileGrid() {
return this.tileGrid;
}
/**
* @param {import("../proj/Projection.js").default} projection Projection.
* @return {!import("../tilegrid/TileGrid.js").default} Tile grid.
*/
getTileGridForProjection(projection) {
if (!this.tileGrid) {
return getTileGridForProjection(projection);
} else {
return this.tileGrid;
}
}
/**
* @param {import("../proj/Projection.js").default} projection Projection.
* @return {import("../TileCache.js").default} Tile cache.
* @protected
*/
getTileCacheForProjection(projection) {
const thisProj = this.getProjection();
if (thisProj && !equivalent(thisProj, projection)) {
return null;
} else {
return this.tileCache;
}
}
/**
* Get the tile pixel ratio for this source. Subclasses may override this
* method, which is meant to return a supported pixel ratio that matches the
* provided `pixelRatio` as close as possible.
* @param {number} pixelRatio Pixel ratio.
* @return {number} Tile pixel ratio.
*/
getTilePixelRatio(pixelRatio) {
return this.tilePixelRatio_;
}
/**
* @param {number} z Z.
* @param {number} pixelRatio Pixel ratio.
* @param {import("../proj/Projection.js").default} projection Projection.
* @return {import("../size.js").Size} Tile size.
*/
getTilePixelSize(z, pixelRatio, projection) {
const tileGrid = this.getTileGridForProjection(projection);
const tilePixelRatio = this.getTilePixelRatio(pixelRatio);
const tileSize = toSize(tileGrid.getTileSize(z), this.tmpSize);
if (tilePixelRatio == 1) {
return tileSize;
} else {
return scaleSize(tileSize, tilePixelRatio, this.tmpSize);
}
}
/**
* Returns a tile coordinate wrapped around the x-axis. When the tile coordinate
* is outside the resolution and extent range of the tile grid, `null` will be
* returned.
* @param {import("../tilecoord.js").TileCoord} tileCoord Tile coordinate.
* @param {import("../proj/Projection.js").default=} opt_projection Projection.
* @return {import("../tilecoord.js").TileCoord} Tile coordinate to be passed to the tileUrlFunction or
* null if no tile URL should be created for the passed `tileCoord`.
*/
getTileCoordForTileUrlFunction(tileCoord, opt_projection) {
const projection = opt_projection !== undefined ?
opt_projection : this.getProjection();
const tileGrid = this.getTileGridForProjection(projection);
if (this.getWrapX() && projection.isGlobal()) {
tileCoord = wrapX(tileGrid, tileCoord, projection);
}
return withinExtentAndZ(tileCoord, tileGrid) ? tileCoord : null;
}
/**
* Remove all cached tiles from the source. The next render cycle will fetch new tiles.
* @api
*/
clear() {
this.tileCache.clear();
}
/**
* @inheritDoc
*/
refresh() {
this.clear();
super.refresh();
}
/**
* Marks a tile coord as being used, without triggering a load.
* @abstract
* @param {number} z Tile coordinate z.
* @param {number} x Tile coordinate x.
* @param {number} y Tile coordinate y.
* @param {import("../proj/Projection.js").default} projection Projection.
*/
useTile(z, x, y, projection) {}
}
/**
* @classdesc
* Events emitted by {@link module:ol/source/Tile~TileSource} instances are instances of this
* type.
*/
export class TileSourceEvent extends Event {
/**
* @param {string} type Type.
* @param {import("../Tile.js").default} tile The tile.
*/
constructor(type, tile) {
super(type);
/**
* The tile related to the event.
* @type {import("../Tile.js").default}
* @api
*/
this.tile = tile;
}
}
export default TileSource;