feat: add experimental landmark-based voice guidance

src/lib/services/navigation/VoiceGuidance.ts

@@ -0,0 +1,83 @@
+import { OVERPASS_SERVER } from "../hosts";
+import type { OverpassResult } from "../Overpass";
+
+export async function generateVoiceGuidance(maneuver: Maneuver, shape: WorldLocation[]): Promise<string> {
+	const landmarks = await findNearbyLandmarks(shape[maneuver.begin_shape_index]);
+	if(landmarks.length == 0) {
+		return maneuver.verbal_pre_transition_instruction;
+	}
+	console.log("Original instruction:", maneuver.verbal_pre_transition_instruction);
+	return `Hinter ${landmarks[0].tags.name}, ${typeToName(maneuver.type)} auf ${(maneuver.street_names || []).join(", ")}.`;
+}
+
+function typeToName(type: number) {
+	switch (type) {
+		case 4:
+			return "Ziel erreicht";
+		case 5:
+			return "Ziel auf der rechten Seite erreicht";
+		case 6:
+			return "Ziel auf der linken Seite erreicht";
+		case 8:
+			return "Weiterfahren";
+		case 9:
+			return "Leicht rechts abbiegen";
+		case 10:
+			return "Rechts abbiegen";
+		case 11:
+			return "Scharf rechts abbiegen";
+		case 12:
+		case 13:
+			return "Umdrehen";
+		case 14:
+			return "Scharf links abbiegen";
+		case 15:
+			return "Links abbiegen";
+		case 16:
+			return "Leicht links abbiegen";
+		case 20:
+			return "Rechts abfahren";
+		case 21:
+			return "Links abfahren";
+		case 22:
+			return "Geradeaus weiterfahren";
+		case 23:
+			return "Rechts halten";
+		case 24:
+			return "Links halten";
+		case 25:
+			return "Einordnen";
+		case 26:
+		case 27:
+			return "Kreisverkehr";
+		case 37:
+			return "Rechts einordnen";
+		case 38:
+			return "Links einordnen";
+		default:
+			return "Unbekannt";
+	}
+}
+
+export async function findNearbyLandmarks(location: WorldLocation) {
+	const radius = 100;
+	const lat = location.lat;
+	const lon = location.lon;
+	const res = await fetch(OVERPASS_SERVER, {
+			method: "POST",
+			body: `[out:json];
+	(
+		node(around:${radius}, ${lat}, ${lon})["tourism"="artwork"]["name"];
+		way(around:${radius}, ${lat}, ${lon})["tourism"="artwork"]["name"];
+		node(around:${radius}, ${lat}, ${lon})["shop"]["name"];
+		way(around:${radius}, ${lat}, ${lon})["shop"]["name"];
+	);
+	out center tags;`,
+		}).then((res) => res.json() as Promise<OverpassResult>);
+	// Sort by distance to the location
+	return res.elements.sort((a, b) => {
+		const distA = Math.sqrt(Math.pow(a.lat! - lat, 2) + Math.pow(a.lon! - lon, 2));
+		const distB = Math.sqrt(Math.pow(b.lat! - lat, 2) + Math.pow(b.lon! - lon, 2));
+		return distA - distB;
+	});
+}

src/lib/services/navigation/routing.svelte.ts

@@ -3,6 +3,7 @@ import { map } from "$lib/components/lnv/map.svelte";
 import say from "./TTS";
 import type { ValhallaRequest } from "./ValhallaRequest";
 import type { LngLatBoundsLike } from "maplibre-gl";
+import { generateVoiceGuidance } from "./VoiceGuidance";
 
 export const routing = $state({
 	geojson: {
@@ -192,11 +193,13 @@ async function tickRoute() {
 		);
 		if (distanceToEnd <= verbalDistance) {
 			hasAnnouncedPreInstruction = true;
+			const instruction = await generateVoiceGuidance(currentManeuver, polyline);
 			console.log(
 				"[Verbal instruction] ",
-				currentManeuver.verbal_pre_transition_instruction,
+				// currentManeuver.verbal_pre_transition_instruction,
+				instruction
 			);
-			say(currentManeuver.verbal_pre_transition_instruction);
+			say(instruction);
 		}
 	}