Allow plugins to request loading models by path.

PiperOrigin-RevId: 936638157
Change-Id: If594c6a9abac5eb0d62e7d6dce4dc2f558989969

src/experimental/platform/ux/plugin.h

@@ -68,7 +68,8 @@ struct ModelPlugin final {
 
   // Callback for when the plugin wants to load a new model. This function will
   // return a buffer containing the model data as well as the content type of
-  // the buffer. Returns nullptr if no model needs to be loaded.s
+  // the buffer. If buf == model_name, then we assume that model_name stores the
+  // path of the model to load. Returns nullptr if no model needs to be loaded.
   GetModelToLoadFn get_model_to_load = nullptr;
 
   // Callback when a new model is loaded.

src/experimental/studio/app.cc

@@ -421,7 +421,9 @@ void App::ProcessPendingLoads() {
       const char* buf = plugin->get_model_to_load(
           plugin, &size, content_type, sizeof(content_type), model_name,
           sizeof(model_name));
-      if (buf && size) {
+      if (buf && buf == model_name) {
+        LoadModelFromFile(model_name);
+      } else if (buf && size) {
         const std::byte* bytes = reinterpret_cast<const std::byte*>(buf);
         LoadModelFromBuffer({bytes, bytes + size}, content_type, model_name);
       }