fix: guard deck layer arrays against null ids

apps/web/src/widgets/map3d/Map3D.tsx

@@ -195,6 +195,33 @@ function getLayerId(value: unknown): string | null {
   return typeof candidate === "string" ? candidate : null;
 }
 
+function sanitizeDeckLayerList(value: unknown): unknown[] {
+  if (!Array.isArray(value)) return [];
+  const seen = new Set<string>();
+  const out: unknown[] = [];
+  let dropped = 0;
+
+  for (const layer of value) {
+    const layerId = getLayerId(layer);
+    if (!layerId) {
+      dropped += 1;
+      continue;
+    }
+    if (seen.has(layerId)) {
+      dropped += 1;
+      continue;
+    }
+    seen.add(layerId);
+    out.push(layer);
+  }
+
+  if (dropped > 0 && import.meta.env.DEV) {
+    console.warn(`Sanitized deck layer list: dropped ${dropped} invalid/duplicate entries`);
+  }
+
+  return out;
+}
+
 function normalizeAngleDeg(value: number, offset = 0): number {
   const v = value + offset;
   return ((v % 360) + 360) % 360;
@@ -3674,8 +3701,10 @@ export function Map3D({
       );
     }
 
+    const normalizedLayers = sanitizeDeckLayerList(layers);
+
     const deckProps = {
-      layers,
+      layers: normalizedLayers,
       getTooltip:
         projection === "globe"
           ? undefined
@@ -3771,8 +3800,40 @@ export function Map3D({
       },
     } as const;
 
-    if (projection === "globe") globeDeckLayerRef.current?.setProps(deckProps);
-    else overlayRef.current?.setProps(deckProps as unknown as never);
+    const safeDeckProps = { ...deckProps, layers: normalizedLayers };
+    const fallbackDeckProps = { ...safeDeckProps, layers: [] as unknown[] };
+    const applyDeckProps = () => {
+      if (projection === "globe") {
+        const target = globeDeckLayerRef.current;
+        if (!target) return;
+        try {
+          target.setProps(safeDeckProps as never);
+        } catch (e) {
+          console.error("Failed to apply deck props on globe overlay. Falling back to empty deck layer set.", e);
+          try {
+            target.setProps(fallbackDeckProps as never);
+          } catch {
+            // Ignore secondary failure; rendering will recover on next update.
+          }
+        }
+        return;
+      }
+
+      const target = overlayRef.current;
+      if (!target) return;
+      try {
+        target.setProps(safeDeckProps as unknown as never);
+      } catch (e) {
+        console.error("Failed to apply deck props on mercator overlay. Falling back to empty deck layer set.", e);
+        try {
+          target.setProps(fallbackDeckProps as unknown as never);
+        } catch {
+          // Ignore secondary failure.
+        }
+      }
+    };
+
+    applyDeckProps();
   }, [
     projection,
     shipData,

apps/web/src/widgets/map3d/MaplibreDeckCustomLayer.ts

@@ -24,6 +24,7 @@ class MatrixView extends View<MatrixViewState> {
 }
 
 const IDENTITY_4x4: number[] = [1, 0, 0, 0, 0, 1, 0, 0, 0, 0, 1, 0, 0, 0, 0, 1];
+type DeckLayerList = NonNullable<DeckProps<MatrixView[]>["layers"]>;
 
 function readMat4(m: ArrayLike<number>): number[] {
   const out = new Array<number>(16);
@@ -40,6 +41,25 @@ function mat4Changed(a: number[] | undefined, b: ArrayLike<number>): boolean {
   return false;
 }
 
+function getDeckLayerId(value: unknown): string | null {
+  if (!value || typeof value !== "object") return null;
+  const candidate = (value as { id?: unknown }).id;
+  return typeof candidate === "string" ? candidate : null;
+}
+
+function sanitizeDeckLayers(value: unknown): DeckLayerList {
+  if (!Array.isArray(value)) return [] as DeckLayerList;
+  const out: DeckLayerList = [];
+  const seen = new Set<string>();
+  for (const item of value) {
+    const layerId = getDeckLayerId(item);
+    if (!layerId || seen.has(layerId)) continue;
+    seen.add(layerId);
+    out.push(item as DeckLayerList[number]);
+  }
+  return out;
+}
+
 export class MaplibreDeckCustomLayer implements maplibregl.CustomLayerInterface {
   id: string;
   type = "custom" as const;
@@ -67,7 +87,8 @@ export class MaplibreDeckCustomLayer implements maplibregl.CustomLayerInterface
   }
 
   setProps(next: Partial<DeckProps<MatrixView[]>>) {
-    this._deckProps = { ...this._deckProps, ...next };
+    const normalized = next.layers ? { ...next, layers: sanitizeDeckLayers(next.layers) } : next;
+    this._deckProps = { ...this._deckProps, ...normalized };
     if (this._deck) this._deck.setProps(this._deckProps as DeckProps<MatrixView[]>);
     this._map?.triggerRepaint();
   }
@@ -80,17 +101,20 @@ export class MaplibreDeckCustomLayer implements maplibregl.CustomLayerInterface
       // Re-attached after a style change; keep the existing Deck instance so we don't reuse
       // finalized Layer objects (Deck does not allow that).
       this._lastMvp = undefined;
-      this._deck.setProps({
+      const nextDeckProps = {
         ...this._deckProps,
+        layers: sanitizeDeckLayers(this._deckProps.layers),
         canvas: map.getCanvas(),
         // Ensure any pending redraw requests trigger a map repaint again.
         _customRender: () => map.triggerRepaint(),
-      } as DeckProps<MatrixView[]>);
+      };
+      this._deck.setProps(nextDeckProps as DeckProps<MatrixView[]>);
       return;
     }
 
     const deck = new Deck<MatrixView[]>({
       ...this._deckProps,
+      layers: sanitizeDeckLayers(this._deckProps.layers),
       // Share MapLibre's WebGL context + canvas (single context).
       gl: gl as WebGL2RenderingContext,
       canvas: map.getCanvas(),