Provide explicit argument for asset cache ID.

This will allow assets to cache compiled results with different parameters. For example, we could cache both an RGB version of a texture and a Mono version.

PiperOrigin-RevId: 811341377
Change-Id: Ifd6a4ff88661a2b38be47c02d6a666de2c202885

src/user/user_cache.cc

@@ -64,17 +64,17 @@ const std::string* mjCCache::HasAsset(const std::string& id) {
 
 // inserts an asset into the cache, if asset is already in the cache, its data
 // is updated only if the timestamps disagree
-bool mjCCache::Insert(const std::string& modelname, const mjResource *resource,
+bool mjCCache::Insert(const std::string& modelname, const std::string& id, const mjResource *resource,
                       std::shared_ptr<const void> data, std::size_t size) {
   std::lock_guard<std::mutex> lock(mutex_);
 
   // check if asset is too large to fit in the cache
   if ((size_ + size > capacity_) &&
-      lookup_.find(resource->name) == lookup_.end()) {
+      lookup_.find(id) == lookup_.end()) {
     return false;
   }
-  mjCAsset asset(modelname, resource, data, size);
-  auto [it, inserted] = lookup_.insert({resource->name, asset});
+  mjCAsset asset(modelname, id, resource, data, size);
+  auto [it, inserted] = lookup_.insert({id, asset});
   mjCAsset* asset_ptr = &(it->second);
 
   if (!inserted) {
@@ -104,9 +104,9 @@ bool mjCCache::Insert(const std::string& modelname, const mjResource *resource,
 
 // populate data from the cache into the given function, return true if data was
 // copied
-bool mjCCache::PopulateData(const mjResource* resource, mjCDataFunc fn) {
+bool mjCCache::PopulateData(const std::string& id, const mjResource* resource, mjCDataFunc fn) {
   std::lock_guard<std::mutex> lock(mutex_);
-  auto it = lookup_.find(resource->name);
+  auto it = lookup_.find(id);
   if (it == lookup_.end()) {
     return false;
   }

src/user/user_cache.h

@@ -39,9 +39,9 @@ typedef void (*mjCDeallocFunc)(const void*);
 class mjCAsset {
   friend class mjCCache;
  public:
-  mjCAsset(std::string modelname, const mjResource* resource,
+  mjCAsset(std::string modelname, std::string id, const mjResource* resource,
            std::shared_ptr<const void> data, std::size_t size) :
-             id_(resource->name), timestamp_(resource->timestamp),
+             id_(id), timestamp_(resource->timestamp),
              size_(size), data_(std::move(data)) {
     AddReference(modelname);
   }
@@ -136,11 +136,11 @@ class mjCCache {
 
   // inserts an asset into the cache, if asset is already in the cache, its data
   // is updated only if the timestamps disagree
-  bool Insert(const std::string& modelname, const mjResource *resource,
+  bool Insert(const std::string& modelname, const std::string& id, const mjResource *resource,
               std::shared_ptr<const void> data, std::size_t size);
 
   // populate data from the cache into the given function
-  bool PopulateData(const mjResource* resource, mjCDataFunc fn);
+  bool PopulateData(const std::string& id, const mjResource* resource, mjCDataFunc fn);
 
   // deletes the asset from the cache with the given id
   void DeleteAsset(const std::string& id);

src/user/user_mesh.cc

@@ -513,7 +513,7 @@ void mjCMesh::CacheMesh(mjCCache* cache, const mjResource* resource) {
     const mjCMesh* mesh = static_cast<const mjCMesh*>(data);
     delete mesh;
   });
-  cache->Insert("", resource, cached_data, size);
+  cache->Insert("", resource->name, resource, cached_data, size);
 }
 
 namespace {
@@ -1231,7 +1231,7 @@ bool mjCMesh::LoadCachedMesh(mjCCache *cache, const mjResource* resource) {
   };
 
   // check that cached asset has all data
-  return cache->PopulateData(resource, process_mesh);
+  return cache->PopulateData(resource->name, resource, process_mesh);
 }
 
 

src/user/user_objects.cc

@@ -91,7 +91,7 @@ PNGImage PNGImage::Load(const mjCBase* obj, mjResource* resource,
   };
 
   // try loading from cache
-  if (cache && cache->PopulateData(resource, callback)) {
+  if (cache && cache->PopulateData(resource->name, resource, callback)) {
       return image;
   }
 
@@ -139,7 +139,7 @@ PNGImage PNGImage::Load(const mjCBase* obj, mjResource* resource,
     std::shared_ptr<const void> cached_data(cached_image, +[] (const void* data) {
         delete static_cast<const PNGImage*>(data);
       });
-    cache->Insert("", resource, cached_data, size);
+    cache->Insert("", resource->name, resource, cached_data, size);
   }
 
   return image;