Files
openlayers/examples/export-pdf.js
2020-01-21 22:27:28 +01:00

92 lines
2.8 KiB
JavaScript

import Map from '../src/ol/Map.js';
import View from '../src/ol/View.js';
import WKT from '../src/ol/format/WKT.js';
import {Tile as TileLayer, Vector as VectorLayer} from '../src/ol/layer.js';
import {OSM, Vector as VectorSource} from '../src/ol/source.js';
const raster = new TileLayer({
source: new OSM()
});
const format = new WKT();
const feature = format.readFeature(
'POLYGON((10.689697265625 -25.0927734375, 34.595947265625 ' +
'-20.1708984375, 38.814697265625 -35.6396484375, 13.502197265625 ' +
'-39.1552734375, 10.689697265625 -25.0927734375))');
feature.getGeometry().transform('EPSG:4326', 'EPSG:3857');
const vector = new VectorLayer({
source: new VectorSource({
features: [feature]
})
});
const map = new Map({
layers: [raster, vector],
target: 'map',
view: new View({
center: [0, 0],
zoom: 2
})
});
const dims = {
a0: [1189, 841],
a1: [841, 594],
a2: [594, 420],
a3: [420, 297],
a4: [297, 210],
a5: [210, 148]
};
const exportButton = document.getElementById('export-pdf');
exportButton.addEventListener('click', function() {
exportButton.disabled = true;
document.body.style.cursor = 'progress';
const format = document.getElementById('format').value;
const resolution = document.getElementById('resolution').value;
const dim = dims[format];
const width = Math.round(dim[0] * resolution / 25.4);
const height = Math.round(dim[1] * resolution / 25.4);
const size = map.getSize();
const viewResolution = map.getView().getResolution();
map.once('rendercomplete', function() {
const mapCanvas = document.createElement('canvas');
mapCanvas.width = width;
mapCanvas.height = height;
const mapContext = mapCanvas.getContext('2d');
document.querySelectorAll('.ol-layer canvas').forEach(function(canvas) {
if (canvas.width > 0) {
const transform = canvas.style.transform;
// Get the transform parameters from the style's transform matrix
const matrix = transform.match(/^matrix\(([^\(]*)\)$/)[1].split(',').map(Number);
// Apply the transform to the export map context
CanvasRenderingContext2D.prototype.setTransform.apply(mapContext, matrix);
mapContext.drawImage(canvas, 0, 0);
}
});
const pdf = new jsPDF('landscape', undefined, format);
pdf.addImage(mapCanvas.toDataURL('image/jpeg'), 'JPEG', 0, 0, dim[0], dim[1]);
pdf.save('map.pdf');
// Reset original map size
map.setSize(size);
map.getView().setResolution(viewResolution);
exportButton.disabled = false;
document.body.style.cursor = 'auto';
});
// Set print size
const printSize = [width, height];
map.setSize(printSize);
const scaling = Math.min(width / size[0], height / size[1]);
map.getView().setResolution(viewResolution / scaling);
}, false);