Copc - Export (Json5) and Import

[livadiotis]

1. When the scene contains copc and is exported to json5, the url is not written into the potree.json5.
   to fix this please add geometry.url = url; in potree.js within function CopcLoader as showed below

	class CopcLoader {
		static async load(file, callback) {
			const { Copc, Getter } = window.Copc;

			const url = file;
			const getter = Getter.http(url);
			const copc = await Copc.create(getter);

			let geometry = new Potree.PointCloudCopcGeometry(getter, copc);
			 geometry.url = url;
			let root = new Potree.PointCloudCopcGeometryNode(geometry);

2. when importing copc - drag and drop, for filename of the copc to be written in the scene objects list, replace this function export in desktop.js

export function loadDroppedPointcloud(cloudjsPath){
	const normalized = cloudjsPath.replace(/\\/g, "/");
	const segments = normalized.split("/");

	// COPC is a single file (e.g. "myfile.copc.laz"), so the name comes from the
	// file itself. Folder-based formats (cloud.js / metadata.json) are named after
	// their containing folder.
	let name;
	if(normalized.toLowerCase().endsWith(".copc.laz")){
		name = segments.reverse()[0].replace(/\.copc\.laz$/i, "");
	}else{
		name = segments.reverse()[1];
	}

	Potree.loadPointCloud(cloudjsPath).then(e => {
		let pointcloud = e.pointcloud;
		let material = pointcloud.material;

		pointcloud.name = name;

		viewer.scene.addPointCloud(pointcloud);

		let hasRGBA = pointcloud.getAttributes().attributes.find(a => a.name === "rgba") !== undefined
		if(hasRGBA){
			pointcloud.material.activeAttributeName = "rgba";
		}else{
			pointcloud.material.activeAttributeName = "color";
		}

		material.size = 1;
		material.pointSizeType = Potree.PointSizeType.ADAPTIVE;

		viewer.zoomTo(e.pointcloud);
	});
};

Thank you