Add microtasks to render loop to lessen thread-blocking

placemark · Dec 5, 2023 · c0c03d0 · c0c03d0
1 parent 6efd773
commit c0c03d0
Showing 1 changed file with 2 additions and 0 deletions.
diff --git a/lib/backend.ts b/lib/backend.ts
@@ -277,6 +277,7 @@ async function render(bbox: BBOX, options: Options = {}) {
     for (const feature of features) {
       drawn++;
       progress(`Drawing (${drawn} / ${features.length} elements)`);
+      await new Promise<void>((resolve) => resolve());
 
       const name = feature.properties?.name;
       switch (feature.geometry.type) {
@@ -438,6 +439,7 @@ async function render(bbox: BBOX, options: Options = {}) {
     const features = grouped.get(group);
     if (!features) continue;
     for (let feature of features) {
+      await new Promise<void>((resolve) => resolve());
       const name = feature.properties?.name;
       if (!(feature.geometry.type === "LineString" && name)) continue;
       if (labeledNames.has(name) || name.length > MAX_NAME_LENGTH) continue;