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import {Layer} from './Layer';
import * as Util from '../core/Util';
import {toLatLngBounds} from '../geo/LatLngBounds';
import {Bounds} from '../geometry/Bounds';
import * as DomUtil from '../dom/DomUtil';
/*
* @class ImageOverlay
* @aka L.ImageOverlay
* @inherits Interactive layer
*
* Used to load and display a single image over specific bounds of the map. Extends `Layer`.
*
* @example
*
* ```js
* var imageUrl = 'http://www.lib.utexas.edu/maps/historical/newark_nj_1922.jpg',
* imageBounds = [[40.712216, -74.22655], [40.773941, -74.12544]];
* L.imageOverlay(imageUrl, imageBounds).addTo(map);
* ```
*/
export var ImageOverlay = Layer.extend({
// @section
// @aka ImageOverlay options
options: {
// @option opacity: Number = 1.0
// The opacity of the image overlay.
opacity: 1,
// @option alt: String = ''
// Text for the `alt` attribute of the image (useful for accessibility).
alt: '',
// @option interactive: Boolean = false
// If `true`, the image overlay will emit [mouse events](#interactive-layer) when clicked or hovered.
interactive: false,
// @option crossOrigin: Boolean = false
// If true, the image will have its crossOrigin attribute set to ''. This is needed if you want to access image pixel data.
crossOrigin: false,
// @option errorOverlayUrl: String = ''
// URL to the overlay image to show in place of the overlay that failed to load.
errorOverlayUrl: '',
// @option zIndex: Number = 1
// The explicit [zIndex](https://developer.mozilla.org/docs/Web/CSS/CSS_Positioning/Understanding_z_index) of the tile layer.
zIndex: 1,
// @option className: String = ''
// A custom class name to assign to the image. Empty by default.
className: '',
},
initialize: function (url, bounds, options) { // (String, LatLngBounds, Object)
this._url = url;
this._bounds = toLatLngBounds(bounds);
Util.setOptions(this, options);
},
onAdd: function () {
if (!this._image) {
this._initImage();
if (this.options.opacity < 1) {
this._updateOpacity();
}
}
if (this.options.interactive) {
DomUtil.addClass(this._image, 'leaflet-interactive');
this.addInteractiveTarget(this._image);
}
this.getPane().appendChild(this._image);
this._reset();
},
onRemove: function () {
DomUtil.remove(this._image);
if (this.options.interactive) {
this.removeInteractiveTarget(this._image);
}
},
// @method setOpacity(opacity: Number): this
// Sets the opacity of the overlay.
setOpacity: function (opacity) {
this.options.opacity = opacity;
if (this._image) {
this._updateOpacity();
}
return this;
},
setStyle: function (styleOpts) {
if (styleOpts.opacity) {
this.setOpacity(styleOpts.opacity);
}
return this;
},
// @method bringToFront(): this
// Brings the layer to the top of all overlays.
bringToFront: function () {
if (this._map) {
DomUtil.toFront(this._image);
}
return this;
},
// @method bringToBack(): this
// Brings the layer to the bottom of all overlays.
bringToBack: function () {
if (this._map) {
DomUtil.toBack(this._image);
}
return this;
},
// @method setUrl(url: String): this
// Changes the URL of the image.
setUrl: function (url) {
this._url = url;
if (this._image) {
this._image.src = url;
}
return this;
},
// @method setBounds(bounds: LatLngBounds): this
// Update the bounds that this ImageOverlay covers
setBounds: function (bounds) {
this._bounds = toLatLngBounds(bounds);
if (this._map) {
this._reset();
}
return this;
},
getEvents: function () {
var events = {
zoom: this._reset,
viewreset: this._reset
};
if (this._zoomAnimated) {
events.zoomanim = this._animateZoom;
}
return events;
},
// @method: setZIndex(value: Number) : this
// Changes the [zIndex](#imageoverlay-zindex) of the image overlay.
setZIndex: function (value) {
this.options.zIndex = value;
this._updateZIndex();
return this;
},
// @method getBounds(): LatLngBounds
// Get the bounds that this ImageOverlay covers
getBounds: function () {
return this._bounds;
},
// @method getElement(): HTMLElement
// Returns the instance of [`HTMLImageElement`](https://developer.mozilla.org/docs/Web/API/HTMLImageElement)
// used by this overlay.
getElement: function () {
return this._image;
},
_initImage: function () {
var wasElementSupplied = this._url.tagName === 'IMG';
var img = this._image = wasElementSupplied ? this._url : DomUtil.create('img');
DomUtil.addClass(img, 'leaflet-image-layer');
if (this._zoomAnimated) { DomUtil.addClass(img, 'leaflet-zoom-animated'); }
if (this.options.className) { DomUtil.addClass(img, this.options.className); }
img.onselectstart = Util.falseFn;
img.onmousemove = Util.falseFn;
// @event load: Event
// Fired when the ImageOverlay layer has loaded its image
img.onload = Util.bind(this.fire, this, 'load');
img.onerror = Util.bind(this._overlayOnError, this, 'error');
if (this.options.crossOrigin) {
img.crossOrigin = '';
}
if (this.options.zIndex) {
this._updateZIndex();
}
if (wasElementSupplied) {
this._url = img.src;
return;
}
img.src = this._url;
img.alt = this.options.alt;
},
_animateZoom: function (e) {
var scale = this._map.getZoomScale(e.zoom),
offset = this._map._latLngBoundsToNewLayerBounds(this._bounds, e.zoom, e.center).min;
DomUtil.setTransform(this._image, offset, scale);
},
_reset: function () {
var image = this._image,
bounds = new Bounds(
this._map.latLngToLayerPoint(this._bounds.getNorthWest()),
this._map.latLngToLayerPoint(this._bounds.getSouthEast())),
size = bounds.getSize();
DomUtil.setPosition(image, bounds.min);
image.style.width = size.x + 'px';
image.style.height = size.y + 'px';
},
_updateOpacity: function () {
DomUtil.setOpacity(this._image, this.options.opacity);
},
_updateZIndex: function () {
if (this._image && this.options.zIndex !== undefined && this.options.zIndex !== null) {
this._image.style.zIndex = this.options.zIndex;
}
},
_overlayOnError: function () {
// @event error: Event
// Fired when the ImageOverlay layer has loaded its image
this.fire('error');
var errorUrl = this.options.errorOverlayUrl;
if (errorUrl && this._url !== errorUrl) {
this._url = errorUrl;
this._image.src = errorUrl;
}
}
});
// @factory L.imageOverlay(imageUrl: String, bounds: LatLngBounds, options?: ImageOverlay options)
// Instantiates an image overlay object given the URL of the image and the
// geographical bounds it is tied to.
export var imageOverlay = function (url, bounds, options) {
return new ImageOverlay(url, bounds, options);
};
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