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/**
* @module ol/source/DataTile
*/
import DataTile from '../DataTile.js';
import EventType from '../events/EventType.js';
import ReprojDataTile from '../reproj/DataTile.js';
import TileEventType from './TileEventType.js';
import TileSource, {TileSourceEvent} from './Tile.js';
import TileState from '../TileState.js';
import {
createXYZ,
extentFromProjection,
getForProjection as getTileGridForProjection,
} from '../tilegrid.js';
import {equivalent, get as getProjection} from '../proj.js';
import {getUid} from '../util.js';
import {toPromise} from '../functions.js';
import {toSize} from '../size.js';
/**
* @typedef {'anonymous'|'use-credentials'} CrossOriginAttribute
*/
/**
* @typedef {Object} LoaderOptions
* @property {AbortSignal} signal An abort controller signal.
* @property {CrossOriginAttribute} [crossOrigin] The cross-origin attribute for images.
* @property {number} [maxY] The maximum y coordinate at the given z level. Will be undefined if the
* underlying tile grid does not have a known extent.
*/
/**
* Data tile loading function. The function is called with z, x, and y tile coordinates and
* returns {@link import("../DataTile.js").Data data} for a tile or a promise for the same.
* @typedef {function(number, number, number, LoaderOptions) : (import("../DataTile.js").Data|Promise)} Loader
*/
/**
* @typedef {Object} Options
* @property {Loader} [loader] Data loader. Called with z, x, and y tile coordinates.
* Returns {@link import("../DataTile.js").Data data} for a tile or a promise for the same.
* For loaders that generate images, the promise should not resolve until the image is loaded.
* @property {import("./Source.js").AttributionLike} [attributions] Attributions.
* @property {boolean} [attributionsCollapsible=true] Attributions are collapsible.
* @property {number} [maxZoom=42] Optional max zoom level. Not used if `tileGrid` is provided.
* @property {number} [minZoom=0] Optional min zoom level. Not used if `tileGrid` is provided.
* @property {number|import("../size.js").Size} [tileSize=[256, 256]] The pixel width and height of the source tiles.
* This may be different than the rendered pixel size if a `tileGrid` is provided.
* @property {number} [gutter=0] The size in pixels of the gutter around data tiles to ignore.
* This allows artifacts of rendering at tile edges to be ignored.
* Supported data should be wider and taller than the tile size by a value of `2 x gutter`.
* @property {number} [maxResolution] Optional tile grid resolution at level zero. Not used if `tileGrid` is provided.
* @property {import("../proj.js").ProjectionLike} [projection='EPSG:3857'] Tile projection.
* @property {import("../tilegrid/TileGrid.js").default} [tileGrid] Tile grid.
* @property {import("./Source.js").State} [state] The source state.
* @property {boolean} [wrapX=false] Render tiles beyond the antimeridian.
* @property {number} [transition] Transition time when fading in new tiles (in milliseconds).
* @property {number} [bandCount=4] Number of bands represented in the data.
* @property {boolean} [interpolate=false] Use interpolated values when resampling. By default,
* the nearest neighbor is used when resampling.
* @property {CrossOriginAttribute} [crossOrigin='anonymous'] The crossOrigin property to pass to loaders for image data.
* @property {string} [key] Key for use in caching tiles.
*/
/**
* @classdesc
* A source for typed array data tiles.
*
* @fires import("./Tile.js").TileSourceEvent
* @template {import("../Tile.js").default} [TileType=DataTile]
* @extends TileSource
* @api
*/
class DataTileSource extends TileSource {
/**
* @param {Options} options DataTile source options.
*/
constructor(options) {
const projection =
options.projection === undefined ? 'EPSG:3857' : options.projection;
let tileGrid = options.tileGrid;
if (tileGrid === undefined && projection) {
tileGrid = createXYZ({
extent: extentFromProjection(projection),
maxResolution: options.maxResolution,
maxZoom: options.maxZoom,
minZoom: options.minZoom,
tileSize: options.tileSize,
});
}
super({
cacheSize: 0.1, // don't cache on the source
attributions: options.attributions,
attributionsCollapsible: options.attributionsCollapsible,
projection: projection,
tileGrid: tileGrid,
state: options.state,
wrapX: options.wrapX,
transition: options.transition,
interpolate: options.interpolate,
key: options.key,
});
/**
* @private
* @type {number}
*/
this.gutter_ = options.gutter !== undefined ? options.gutter : 0;
/**
* @private
* @type {import('../size.js').Size|null}
*/
this.tileSize_ = options.tileSize ? toSize(options.tileSize) : null;
/**
* @private
* @type {Array|null}
*/
this.tileSizes_ = null;
/**
* @private
* @type {!Object}
*/
this.tileLoadingKeys_ = {};
/**
* @private
*/
this.loader_ = options.loader;
/**
* @private
*/
this.handleTileChange_ = this.handleTileChange_.bind(this);
/**
* @type {number}
*/
this.bandCount = options.bandCount === undefined ? 4 : options.bandCount; // assume RGBA if undefined
/**
* @private
* @type {!Object}
*/
this.tileGridForProjection_ = {};
/**
* @private
* @type {CrossOriginAttribute}
*/
this.crossOrigin_ = options.crossOrigin || 'anonymous';
}
/**
* Set the source tile sizes. The length of the array is expected to match the number of
* levels in the tile grid.
* @protected
* @param {Array} tileSizes An array of tile sizes.
*/
setTileSizes(tileSizes) {
this.tileSizes_ = tileSizes;
}
/**
* Get the source tile size at the given zoom level. This may be different than the rendered tile
* size.
* @protected
* @param {number} z Tile zoom level.
* @return {import('../size.js').Size} The source tile size.
*/
getTileSize(z) {
if (this.tileSizes_) {
return this.tileSizes_[z];
}
if (this.tileSize_) {
return this.tileSize_;
}
const tileGrid = this.getTileGrid();
return tileGrid ? toSize(tileGrid.getTileSize(z)) : [256, 256];
}
/**
* @param {import("../proj/Projection.js").default} projection Projection.
* @return {number} Gutter.
* @override
*/
getGutterForProjection(projection) {
const thisProj = this.getProjection();
if (!thisProj || equivalent(thisProj, projection)) {
return this.gutter_;
}
return 0;
}
/**
* @param {Loader} loader The data loader.
* @protected
*/
setLoader(loader) {
this.loader_ = loader;
}
/**
* @param {number} z Tile coordinate z.
* @param {number} x Tile coordinate x.
* @param {number} y Tile coordinate y.
* @param {import("../proj/Projection.js").default} targetProj The output projection.
* @param {import("../proj/Projection.js").default} sourceProj The input projection.
* @return {!TileType} Tile.
*/
getReprojTile_(z, x, y, targetProj, sourceProj) {
const tileGrid = this.getTileGrid();
const reprojTilePixelRatio = Math.max.apply(
null,
tileGrid.getResolutions().map((r, z) => {
const tileSize = toSize(tileGrid.getTileSize(z));
const textureSize = this.getTileSize(z);
return Math.max(
textureSize[0] / tileSize[0],
textureSize[1] / tileSize[1],
);
}),
);
const sourceTileGrid = this.getTileGridForProjection(sourceProj);
const targetTileGrid = this.getTileGridForProjection(targetProj);
const tileCoord = [z, x, y];
const wrappedTileCoord = this.getTileCoordForTileUrlFunction(
tileCoord,
targetProj,
);
const options = Object.assign(
{
sourceProj,
sourceTileGrid,
targetProj,
targetTileGrid,
tileCoord,
wrappedTileCoord,
pixelRatio: reprojTilePixelRatio,
gutter: this.getGutterForProjection(sourceProj),
getTileFunction: (z, x, y, pixelRatio) =>
this.getTile(z, x, y, pixelRatio, sourceProj),
},
/** @type {import("../reproj/DataTile.js").Options} */ (this.tileOptions),
);
const tile = /** @type {TileType} */ (
/** @type {*} */ (new ReprojDataTile(options))
);
tile.key = this.getKey();
return tile;
}
/**
* @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 {TileType|null} Tile (or null if outside source extent).
* @override
*/
getTile(z, x, y, pixelRatio, projection) {
const sourceProjection = this.getProjection();
if (
sourceProjection &&
projection &&
!equivalent(sourceProjection, projection)
) {
return this.getReprojTile_(z, x, y, projection, sourceProjection);
}
const size = this.getTileSize(z);
const sourceLoader = this.loader_;
const controller = new AbortController();
/**
* @type {LoaderOptions}
*/
const loaderOptions = {
signal: controller.signal,
crossOrigin: this.crossOrigin_,
};
const tileCoord = this.getTileCoordForTileUrlFunction([z, x, y]);
if (!tileCoord) {
return null;
}
const requestZ = tileCoord[0];
const requestX = tileCoord[1];
const requestY = tileCoord[2];
function loader() {
return toPromise(function () {
return sourceLoader(requestZ, requestX, requestY, loaderOptions);
});
}
/**
* @type {import("../DataTile.js").Options}
*/
const options = Object.assign(
{
tileCoord: [z, x, y],
loader: loader,
size: size,
controller: controller,
},
this.tileOptions,
);
const tile = /** @type {TileType} */ (
/** @type {*} */ (new DataTile(options))
);
tile.key = this.getKey();
tile.addEventListener(EventType.CHANGE, this.handleTileChange_);
return tile;
}
/**
* Handle tile change events.
* @param {import("../events/Event.js").default} event Event.
*/
handleTileChange_(event) {
const tile = /** @type {import("../Tile.js").default} */ (event.target);
const uid = getUid(tile);
const tileState = tile.getState();
let type;
if (tileState == TileState.LOADING) {
this.tileLoadingKeys_[uid] = true;
type = TileEventType.TILELOADSTART;
} else if (uid in this.tileLoadingKeys_) {
delete this.tileLoadingKeys_[uid];
type =
tileState == TileState.ERROR
? TileEventType.TILELOADERROR
: tileState == TileState.LOADED
? TileEventType.TILELOADEND
: undefined;
}
if (type) {
this.dispatchEvent(new TileSourceEvent(type, tile));
}
}
/**
* @param {import("../proj/Projection.js").default} projection Projection.
* @return {!import("../tilegrid/TileGrid.js").default} Tile grid.
* @override
*/
getTileGridForProjection(projection) {
const thisProj = this.getProjection();
if (this.tileGrid && (!thisProj || equivalent(thisProj, projection))) {
return this.tileGrid;
}
const projKey = getUid(projection);
if (!(projKey in this.tileGridForProjection_)) {
this.tileGridForProjection_[projKey] =
getTileGridForProjection(projection);
}
return this.tileGridForProjection_[projKey];
}
/**
* Sets the tile grid to use when reprojecting the tiles to the given
* projection instead of the default tile grid for the projection.
*
* This can be useful when the default tile grid cannot be created
* (e.g. projection has no extent defined) or
* for optimization reasons (custom tile size, resolutions, ...).
*
* @param {import("../proj.js").ProjectionLike} projection Projection.
* @param {import("../tilegrid/TileGrid.js").default} tilegrid Tile grid to use for the projection.
* @api
*/
setTileGridForProjection(projection, tilegrid) {
const proj = getProjection(projection);
if (proj) {
const projKey = getUid(proj);
if (!(projKey in this.tileGridForProjection_)) {
this.tileGridForProjection_[projKey] = tilegrid;
}
}
}
}
export default DataTileSource;