Fix an endless loop in updateViewGroupOffline when it's given an empty list of frustums

CHANGES.md

@@ -1,5 +1,11 @@
 # Change Log
 
+### ? - ?
+
+##### Fixes :wrench:
+
+- Fixed a bug in `Tileset::updateViewGroupOffline` that would cause it to get stuck in an endless loop when invoked with no frustums.
+
 ### v0.50.0 - 2025-08-01
 
 ##### Breaking Changes :mega:

Cesium3DTilesSelection/src/Tileset.cpp

@@ -334,6 +334,12 @@ const ViewUpdateResult& Tileset::updateViewGroupOffline(
   while (viewGroup.getPreviousLoadProgressPercentage() < 100.0f) {
     this->_externals.pAssetAccessor->tick();
     this->loadTiles();
+
+    // If there are no frustums, we'll never make any progress. So break here to
+    // avoid getting stuck in an endless loop.
+    if (frustums.empty())
+      break;
+
     this->updateViewGroup(viewGroup, frustums, 0.0f);
   }
 

Cesium3DTilesSelection/test/TestTilesetSelectionAlgorithm.cpp

@@ -550,6 +550,13 @@ TEST_CASE("Test replace refinement for render") {
       REQUIRE(result.culledTilesVisited == 0);
     }
   }
+
+  SUBCASE(
+      "updateViewGroupOffline does not get stuck in an endless loop when no "
+      "frustums are given") {
+    std::vector<ViewState> empty;
+    tileset.updateViewGroupOffline(tileset.getDefaultViewGroup(), empty);
+  }
 }
 
 TEST_CASE("Test additive refinement") {