kmap-ui
Version:
A components of zmap base on vue2.X
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JavaScript
/* Copyright (c) 2015 Jean-Marc VIGLINO,
released under the CeCILL-B license (French BSD license)
(http://www.cecill.info/licences/Licence_CeCILL-B_V1-en.txt).
ol_source_GeoImage is a layer source with georeferencement to place it on a map.
olx.source.GeoImageOptions:
{ url: {string} url of the static image
image: {image} the static image, if not provided, use url to load an image
imageCenter: {ol.Coordinate} of the center of the image
imageScale: {ol.Size|Number} [scalex, scaley] of the image
imageRotate: {number} angle of the image in radian, default 0
imageCrop: {ol.Extent} of the image to be show (in the image) default: [0,0,imageWidth,imageHeight]
imageMask: {Array.<ol.Coordinate>} - linestring to mask the image on the map
}
*/
import ol_ext_inherits from '../util/ext'
import ol_source_ImageCanvas from 'ol/source/ImageCanvas'
import ol_geom_Polygon from 'ol/geom/Polygon'
import {boundingExtent as ol_extent_boundingExtent} from 'ol/extent'
import {fromExtent as ol_geom_Polygon_fromExtent} from 'ol/geom/Polygon'
/** Layer source with georeferencement to place it on a map
* @constructor
* @extends {ol_source_ImageCanvas}
* @param {olx.source.GeoImageOptions=} options
*/
var ol_source_GeoImage = function(opt_options) {
var options = {
attributions: opt_options.attributions,
logo: opt_options.logo,
projection: opt_options.projection
};
// options.projection = opt_options.projection;
// Coordinate of the image center
this.center = opt_options.imageCenter;
// Scale of the image
this.scale = opt_options.imageScale;
// Rotation of the image
this.rotate = opt_options.imageRotate ? opt_options.imageRotate : 0;
// Crop of the image
this.crop = opt_options.imageCrop;
// Mask of the image
this.mask = opt_options.imageMask;
// Load Image
this._image = (opt_options.image ? opt_options.image : new Image );
this._image.crossOrigin = opt_options.crossOrigin; // 'anonymous';
// Show image on load
var self = this;
this._image.onload = function() {
self.setCrop (self.crop);
self.changed();
}
if (!opt_options.image) this._image.src = opt_options.url;
// Draw image on canvas
options.canvasFunction = function(extent, resolution, pixelRatio, size /*, projection*/ ) {
var canvas = document.createElement('canvas');
canvas.width = size[0];
canvas.height = size[1];
var ctx = canvas.getContext('2d');
if (!this._imageSize) return canvas;
// transform coords to pixel
function tr(xy) {
return [
(xy[0]-extent[0])/(extent[2]-extent[0]) * size[0],
(xy[1]-extent[3])/(extent[1]-extent[3]) * size[1]
];
}
// Clipping mask
if (this.mask) {
ctx.beginPath();
var p = tr(this.mask[0]);
ctx.moveTo(p[0],p[1]);
for (var i=1; i<this.mask.length; i++) {
p = tr(this.mask[i]);
ctx.lineTo(p[0],p[1]);
}
ctx.clip();
}
// Draw
var pixel = tr(this.center);
var dx = (this._image.naturalWidth/2 - this.crop[0]) *this.scale[0] /resolution *pixelRatio;
var dy = (this._image.naturalHeight/2 - this.crop[1]) *this.scale[1] /resolution *pixelRatio;
var sx = this._imageSize[0]*this.scale[0]/resolution *pixelRatio;
var sy = this._imageSize[1]*this.scale[1]/resolution *pixelRatio;
ctx.translate(pixel[0],pixel[1]);
if (this.rotate) ctx.rotate(this.rotate);
ctx.drawImage(this._image, this.crop[0], this.crop[1], this._imageSize[0], this._imageSize[1], -dx, -dy, sx,sy);
return canvas;
}
ol_source_ImageCanvas.call (this, options);
this.setCrop (this.crop);
// Calculate extent on change
this.on('change', function() {
this.set('extent', this.calculateExtent());
}.bind(this));
};
ol_ext_inherits(ol_source_GeoImage, ol_source_ImageCanvas);
/**
* Get coordinate of the image center.
* @return {ol.Coordinate} coordinate of the image center.
* @api stable
*/
ol_source_GeoImage.prototype.getCenter = function() {
return this.center;
}
/**
* Set coordinate of the image center.
* @param {ol.Coordinate} coordinate of the image center.
* @api stable
*/
ol_source_GeoImage.prototype.setCenter = function(center) {
this.center = center;
this.changed();
}
/**
* Get image scale.
* @return {ol.size} image scale (along x and y axis).
* @api stable
*/
ol_source_GeoImage.prototype.getScale = function() {
return this.scale;
}
/**
* Set image scale.
* @param {ol.size|Number} image scale (along x and y axis or both).
* @api stable
*/
ol_source_GeoImage.prototype.setScale = function(scale) {
switch (typeof(scale)) {
case 'number':
scale = [scale,scale];
break;
case 'object':
if (scale.length != 2) return;
break;
default: return;
}
this.scale = scale;
this.changed();
};
/**
* Get image rotation.
* @return {Number} rotation in degre.
* @api stable
*/
ol_source_GeoImage.prototype.getRotation = function() {
return this.rotate;
};
/**
* Set image rotation.
* @param {Number} rotation in radian.
* @api stable
*/
ol_source_GeoImage.prototype.setRotation = function(angle) {
this.rotate = angle;
this.changed();
};
/**
* Get the image.
* @api stable
*/
ol_source_GeoImage.prototype.getGeoImage = function() {
return this._image;
};
/**
* Get image crop extent.
* @return {ol.extent} image crop extent.
* @api stable
*/
ol_source_GeoImage.prototype.getCrop = function() {
return this.crop;
};
/**
* Set image mask.
* @param {ol.geom.LineString} coords of the mask
* @api stable
*/
ol_source_GeoImage.prototype.setMask = function(mask) {
this.mask = mask;
this.changed();
};
/**
* Get image mask.
* @return {ol.geom.LineString} coords of the mask
* @api stable
*/
ol_source_GeoImage.prototype.getMask = function() {
return this.mask;
};
/**
* Set image crop extent.
* @param {ol.extent|Number} image crop extent or a number to crop from original size.
* @api stable
*/
ol_source_GeoImage.prototype.setCrop = function(crop) {
// Image not loaded => get it latter
if (!this._image.naturalWidth) {
this.crop = crop;
return;
}
if (crop) {
switch (typeof(crop)) {
case 'number':
crop = [crop,crop,this._image.naturalWidth-crop,this._image.naturalHeight-crop];
break;
case 'object':
if (crop.length != 4) return;
break;
default: return;
}
crop = ol_extent_boundingExtent([ [crop[0],crop[1]], [crop[2],crop[3]] ]);
this.crop = [ Math.max(0,crop[0]), Math.max(0,crop[1]), Math.min(this._image.naturalWidth,crop[2]), Math.min(this._image.naturalHeight,crop[3]) ];
}
else this.crop = [0,0, this._image.naturalWidth,this._image.naturalHeight];
if (this.crop[2]<=this.crop[0]) this.crop[2] = this.crop[0]+1;
if (this.crop[3]<=this.crop[1]) this.crop[3] = this.crop[1]+1;
this._imageSize = [ this.crop[2]-this.crop[0], this.crop[3]-this.crop[1] ];
this.changed();
};
/** Get the extent of the source.
* @param {module:ol/extent~Extent} extent If provided, no new extent will be created. Instead, that extent's coordinates will be overwritten.
* @return {ol.extent}
*/
ol_source_GeoImage.prototype.getExtent = function(opt_extent) {
if (opt_extent) {
var ext = this.get('extent');
for (var i=0; i<opt_extent.length; i++) {
opt_extent[i] = ext[i];
}
return ext;
} else {
return this.get('extent');
}
};
/** Calculate the extent of the source image.
* @param {boolean} usemask return the mask extent, default return the image extent
* @return {ol.extent}
*/
ol_source_GeoImage.prototype.calculateExtent = function(usemask) {
var polygon;
if (usemask!==false && this.getMask()) {
polygon = new ol_geom_Polygon([this.getMask()])
} else {
var center = this.getCenter();
var scale = this.getScale();
var width = this.getGeoImage().width * scale[0];
var height = this.getGeoImage().height * scale[1];
var extent = ol_extent_boundingExtent([
[ center[0]-width/2, center[1]-height/2 ],
[ center[0]+width/2, center[1]+height/2 ]
]);
polygon = ol_geom_Polygon_fromExtent(extent);
polygon.rotate(-this.getRotation(), center);
}
var ext = polygon.getExtent();
return ext;
};
export default ol_source_GeoImage