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| import Feature from 'ol/Feature.js';
import Map from 'ol/Map.js';
import View from 'ol/View.js';
import {Circle} from 'ol/geom.js';
import {OSM, Vector as VectorSource} from 'ol/source.js';
import {Style} from 'ol/style.js';
import {Tile as TileLayer, Vector as VectorLayer} from 'ol/layer.js';
const circleFeature = new Feature({
geometry: new Circle([12127398.797692968, 4063894.123105166], 50),
});
circleFeature.setStyle(
new Style({
renderer(coordinates, state) {
const [[x, y], [x1, y1]] = coordinates;
const ctx = state.context;
const dx = x1 - x;
const dy = y1 - y;
const radius = Math.sqrt(dx * dx + dy * dy);
const innerRadius = 0;
const outerRadius = radius * 1.4;
const gradient = ctx.createRadialGradient(
x,
y,
innerRadius,
x,
y,
outerRadius
);
gradient.addColorStop(0, 'rgba(255,0,0,0)');
gradient.addColorStop(0.6, 'rgba(255,0,0,0.2)');
gradient.addColorStop(1, 'rgba(255,0,0,0.8)');
ctx.beginPath();
ctx.arc(x, y, radius, 0, 2 * Math.PI, true);
ctx.fillStyle = gradient;
ctx.fill();
ctx.arc(x, y, radius, 0, 2 * Math.PI, true);
ctx.strokeStyle = 'rgba(255,0,0,1)';
ctx.stroke();
},
})
);
new Map({
layers: [
new TileLayer({
source: new OSM(),
visible: true,
}),
new VectorLayer({
source: new VectorSource({
features: [circleFeature],
}),
}),
],
target: 'map',
view: new View({
center: [12127398.797692968, 4063894.123105166],
zoom: 19,
}),
});
|
)
