Display a TopoJSON file on a Map.
import TopoJSON from "ol/format/TopoJSON.js";
import OSM from "ol/source/OSM.js";
import { Fill, Stroke, Style } from "ol/style.js";
import { MapControls } from "three/examples/jsm/controls/MapControls.js";
import { CSS2DObject } from "three/examples/jsm/renderers/CSS2DRenderer.js";
import ColorLayer from "@giro3d/giro3d/core/layer/ColorLayer.js";
import Extent from "@giro3d/giro3d/core/geographic/Extent.js";
import Instance from "@giro3d/giro3d/core/Instance.js";
import Map from "@giro3d/giro3d/entities/Map.js";
import VectorSource from "@giro3d/giro3d/sources/VectorSource.js";
import Inspector from "@giro3d/giro3d/gui/Inspector.js";
import TiledImageSource from "@giro3d/giro3d/sources/TiledImageSource.js";
import Coordinates from "@giro3d/giro3d/core/geographic/Coordinates.js";
Instance.registerCRS(
"EPSG:30174",
"+proj=tmerc +lat_0=26 +lon_0=142 +k=0.9999 +x_0=0 +y_0=0 +ellps=bessel +towgs84=-146.414,507.337,680.507,0,0,0,0 +units=m +no_defs +type=crs",
);
const extent = new Extent(
"EPSG:30174",
-201012.900985493,
-198191.63799031873,
1066954.2964232096,
1071890.8856167798,
);
const instance = new Instance({
target: "view",
crs: extent.crs,
});
const center = extent.centerAsVector2();
instance.view.camera.position.set(center.x, center.y - 1, 2000);
const controls = new MapControls(instance.view.camera, instance.domElement);
controls.enableDamping = true;
controls.dampingFactor = 0.25;
controls.target.set(center.x, center.y, 0);
instance.view.setControls(controls);
const map = new Map({ extent, backgroundColor: "#135D66" });
instance.add(map);
const buildingsStyle = (feature) => {
const highlight = feature.get("highlight");
const stroke = highlight
? new Stroke({
color: "white",
width: 2,
})
: undefined;
return new Style({
zIndex: highlight ? 1 : 0,
fill: new Fill({
color: highlight ? "green" : "red",
}),
stroke,
});
};
const topoJsonSource = new VectorSource({
data: {
url: "https://3d.oslandia.com/giro3d/vectors/tokyo_buildings.topojson",
format: new TopoJSON(),
},
dataProjection: "EPSG:4326",
style: buildingsStyle,
});
const buildingsLayer = new ColorLayer({
name: "Buildings",
extent,
source: topoJsonSource,
});
// Create the OpenStreetMap color layer using an OpenLayers source.
// See https://openlayers.org/en/latest/apidoc/module-ol_source_OSM-OSM.html
// for more informations.
const osm = new ColorLayer({
name: "osm",
source: new TiledImageSource({ source: new OSM() }),
extent,
});
map.addLayer(osm);
map.addLayer(buildingsLayer);
const labelElement = document.createElement("span");
labelElement.classList.value = "badge rounded-pill text-bg-light";
labelElement.style.marginTop = "2rem";
const label = new CSS2DObject(labelElement);
label.visible = false;
instance.add(label);
let previousFeature;
function pickFeatures(mouseEvent) {
const pickResult = instance.pickObjectsAt(mouseEvent, {
radius: 0,
});
const picked = pickResult[0];
function resetPickedFeatures() {
if (previousFeature) {
previousFeature.set("highlight", false);
topoJsonSource.updateFeature(previousFeature);
}
if (label.visible) {
label.visible = false;
}
previousFeature = null;
}
if (picked) {
const { x, y } = picked.point;
const features = buildingsLayer.getVectorFeaturesAtCoordinate(
new Coordinates(instance.referenceCrs, x, y),
);
if (features.length > 0) {
const firstFeature = features[0];
previousFeature?.set("highlight", false);
firstFeature.set("highlight", true);
if (previousFeature !== firstFeature) {
topoJsonSource.updateFeature(previousFeature, firstFeature);
previousFeature = firstFeature;
}
instance.notifyChange(map);
label.position.set(x, y, 100);
label.visible = true;
label.element.innerText = firstFeature.get("osm_id");
label.updateMatrixWorld(true);
} else {
resetPickedFeatures();
}
} else {
resetPickedFeatures();
}
}
instance.domElement.addEventListener("mousemove", pickFeatures);
instance.domElement.addEventListener("dblclick", (e) =>
console.log(instance.pickObjectsAt(e)),
);
Inspector.attach("inspector", instance);
instance.notifyChange(map);
<!doctype html>
<html lang="en">
<head>
<title>TopoJSON</title>
<meta charset="UTF-8" />
<meta name="name" content="ol_vector_topojson" />
<meta name="description" content="Display a TopoJSON file on a Map." />
<meta name="viewport" content="width=device-width, initial-scale=1.0" />
<link rel="icon" href="https://giro3d.org/images/favicon.svg" />
<link
href="https://giro3d.org/assets/bootstrap-custom.css"
rel="stylesheet"
/>
<script src="https://giro3d.org/assets/bootstrap.bundle.min.js"></script>
<link
rel="stylesheet"
type="text/css"
href="https://giro3d.org/latest/examples/css/example.css"
/>
</head>
<body>
<div id="view" class="m-0 p-0 w-100 h-100"></div>
<div
id="inspector"
class="position-absolute top-0 start-0 mh-100 overflow-auto"
></div>
<script type="module" src="index.js"></script>
<script>
/* activate popovers */
const popoverTriggerList = [].slice.call(
document.querySelectorAll('[data-bs-toggle="popover"]'),
);
popoverTriggerList.map(
// bootstrap is used as script in the template, disable warning about undef
// eslint-disable-next-line no-undef
(popoverTriggerEl) =>
new bootstrap.Popover(popoverTriggerEl, {
trigger: "hover",
placement: "left",
content: document.getElementById(
popoverTriggerEl.getAttribute("data-bs-content"),
).innerHTML,
html: true,
}),
);
</script>
</body>
</html>
{
"name": "ol_vector_topojson",
"dependencies": {
"@giro3d/giro3d": "0.41.0"
},
"devDependencies": {
"vite": "^3.2.3"
},
"scripts": {
"start": "vite",
"build": "vite build"
}
}