promote cacheid type to long int and fix update of the stage counter (A…

…utodesk#1953)

CHANGELOG.md

@@ -15,6 +15,7 @@
 - [usd#1661](https://github.com/Autodesk/arnold-usd/issues/1661) - In the procedural the subdivision meshes will use the normals generated by the subdivision algorithm instead of the normal primvar.
 - [usd#1919](https://github.com/Autodesk/arnold-usd/issues/1919) - Fix rendering multiple frames with husk.
 - [usd#1952](https://github.com/Autodesk/arnold-usd/issues/1952) - Don't write camera aperture parameters if they're already set
+- [usd#1902](https://github.com/Autodesk/arnold-usd/issues/1902) - Fix invalid Cache ID sporadic error
 
 ## Pending bugfix release
 - [usd#1940](https://github.com/Autodesk/arnold-usd/issues/1940) - Incorrect handling of shaders referenced in multiple materials

libs/common/procedural_reader.cpp

@@ -79,7 +79,7 @@ void ProceduralReader::Read(const std::string &filename,
     _overrides = nullptr; // clear the overrides pointer. Note that we don't own this array
 }
 
-bool ProceduralReader::Read(int cacheId, const std::string &path)
+bool ProceduralReader::Read(long int cacheId, const std::string &path)
 {
     if (!GetNodes().empty()) {
         return true;

libs/common/procedural_reader.h

@@ -30,18 +30,18 @@ class ProceduralReader {
 
     const std::string &GetFilename() const { return _filename; }
     const AtArray *GetOverrides() const { return _overrides; }
-    int GetCacheId() const {return _cacheId;}
+    long int GetCacheId() const {return _cacheId;}
     void SetInteractive(bool b) {_interactive = b;}
     bool GetInteractive() const {return _interactive;}
 
     void Read(const std::string &filename, 
         AtArray *overrides, const std::string &path = "");
 
-    bool Read(int cacheId, const std::string &path = "");
+    bool Read(long int cacheId, const std::string &path = "");
     virtual void Update() {} // Update scene for interactive changes
 protected:
     std::string _filename;
     AtArray *_overrides = nullptr;
-    int _cacheId = 0;   // usdStage cacheID used with a StageCache
+    long int _cacheId = 0;   // usdStage cacheID used with a StageCache
     bool _interactive = false; // interactive readers can update Arnold when the usdStage changes
 };

libs/translator/reader/reader.cpp

@@ -86,7 +86,7 @@ namespace {
 
 
 static AtMutex s_globalReaderMutex;
-static std::unordered_map<int, int> s_cacheRefCount;
+static std::unordered_map<long int, int> s_cacheRefCount;
 UsdArnoldReader::UsdArnoldReader()
         : _procParent(nullptr),
           _universe(nullptr),
@@ -1039,8 +1039,8 @@ void UsdArnoldReader::InitCacheId()
     UsdStageCache::Id id = stageCache.Insert(_stage);
     // now our reader will have a cacheID
     _cacheId = id.ToLongInt();
-    // there's one ref count for this cache ID, for the current proc
-    s_cacheRefCount[_cacheId] = 1; 
+    // stageCache.Insert can return an existing stage, so we increase the ref count for that stage in case it exists
+    s_cacheRefCount[_cacheId]++; 
 }
 // Return a AtNode representing a whole part of the scene hierarchy, as needed e.g. for instancing.
 // In this case, we create a nested procedural and give it an "object_path" so that it only represents 
@@ -1069,7 +1069,15 @@ AtNode *UsdArnoldReader::CreateNestedProc(const char *objectPath, UsdArnoldReade
             cacheIdIter->second++;        
     }
 
-    AiNodeSetInt(proto, str::cache_id, _cacheId);
+
+    // The current USD stageCache implementation use an ID counter which starts at 9223000 and increase it everytime a stage is added.
+    // So it should most likely stay in the integer range. But if the implementation changes, we need to make sure we catch it.
+    // We could/should probably store it as string. TBD
+    if (_cacheId <= std::numeric_limits<int>::max() && _cacheId >= std::numeric_limits<int>::min()) {
+        AiNodeSetInt(proto, str::cache_id, static_cast<int>(_cacheId));
+    } else {
+        AiMsgWarning("[usd] Cache ID is larger that what can be stored in arnold parameter %ld", _cacheId);
+    }
     AiNodeSetStr(proto, str::object_path, AtString(objectPath));
     AiNodeSetFlt(proto, str::frame, time.frame); // give it the desired frame
     AiNodeSetFlt(proto, str::motion_start, time.motionStart);

plugins/procedural/main.cpp

@@ -331,15 +331,15 @@ std::string USDLibraryPath()
 
 extern "C"
 {
-    DLLEXPORT void WriteUsdStageCache ( const AtUniverse* universe, int cacheId, const AtParamValueMap* params )
+    DLLEXPORT void WriteUsdStageCache ( const AtUniverse* universe, long int cacheId, const AtParamValueMap* params )
     {
         // Get the UsdStageCache, it's common to all libraries linking against the same USD libs
         UsdStageCache &stageCache = UsdUtilsStageCache::Get();
         UsdStageCache::Id id = UsdStageCache::Id::FromLongInt(cacheId);
         // Retrieve the UsdStage associated to this cache ID.
         UsdStageRefPtr stage = (id.IsValid()) ? stageCache.Find(id) : nullptr;
         if (!stage) {
-            AiMsgError("[usd] Cache ID not valid %d", cacheId);
+            AiMsgError("[usd] Cache ID not valid %ld", cacheId);
             return;
         }
         // Create an Arnold-USD writer, that can write an Arnold univers to a UsdStage