Increase inventory capacity with base-100 encoding for values up to 25599

packages/mettagrid/cpp/include/mettagrid/objects/chest.hpp

@@ -1,6 +1,7 @@
 #ifndef PACKAGES_METTAGRID_CPP_INCLUDE_METTAGRID_OBJECTS_CHEST_HPP_
 #define PACKAGES_METTAGRID_CPP_INCLUDE_METTAGRID_OBJECTS_CHEST_HPP_
 
+#include <algorithm>
 #include <set>
 #include <unordered_map>
 #include <vector>
@@ -125,7 +126,8 @@ class Chest : public GridObject, public Usable, public HasInventory {
       throw std::runtime_error("Observation encoder not set for chest");
     }
     std::vector<PartialObservationToken> features;
-    features.reserve(1 + this->inventory.get().size() + this->tag_ids.size() + 3);
+    // Up to 2 tokens per inventory item (low byte + optional high byte)
+    features.reserve(1 + this->inventory.get().size() * 2 + this->tag_ids.size() + (this->vibe != 0 ? 1 : 0));
 
     if (this->vibe != 0) features.push_back({ObservationFeature::Vibe, static_cast<ObservationType>(this->vibe)});
 

packages/mettagrid/cpp/include/mettagrid/objects/inventory.hpp

@@ -1,6 +1,7 @@
 #ifndef PACKAGES_METTAGRID_CPP_INCLUDE_METTAGRID_OBJECTS_INVENTORY_HPP_
 #define PACKAGES_METTAGRID_CPP_INCLUDE_METTAGRID_OBJECTS_INVENTORY_HPP_
 
+#include <limits>
 #include <string>
 #include <unordered_map>
 #include <vector>

packages/mettagrid/cpp/src/mettagrid/objects/agent.cpp

@@ -209,7 +209,7 @@ std::vector<PartialObservationToken> Agent::obs_features() const {
   if (!this->obs_encoder) {
     throw std::runtime_error("Observation encoder not set for agent");
   }
-  const size_t num_tokens = this->inventory.get().size() + this->tag_ids.size() + 5;
+  const size_t num_tokens = this->inventory.get().size() * 2 + this->tag_ids.size() + 5;
 
   std::vector<PartialObservationToken> features;
   features.reserve(num_tokens);

packages/mettagrid/docs/simulator_api.md

@@ -265,9 +265,11 @@ obs = agent.observation
 for token in obs.tokens:
     if token.feature.name == "object_type":
         print(f"Object at ({token.col()}, {token.row()}): {token.value}")
-    elif token.feature.name.startswith("inv:"):
-        resource = token.feature.name[4:]  # Remove "inv:" prefix
-        print(f"Inventory {resource}: {token.value}")
+
+# For inventory, use the agent.inventory property which handles the encoding
+inventory = agent.inventory
+for resource, amount in inventory.items():
+    print(f"Inventory {resource}: {amount}")
 ```
 
 ## Event Handling

packages/mettagrid/python/src/mettagrid/config/mettagrid_c_config.py

@@ -348,9 +348,7 @@ def convert_to_cpp_game_config(mettagrid_config: dict | GameConfig):
                         if name in resource_name_to_id
                     }
                     limit_defs.append(
-                        CppLimitDef(
-                            resources=resource_ids, base_limit=min(resource_limit.limit, 255), modifiers=modifier_ids
-                        )
+                        CppLimitDef(resources=resource_ids, base_limit=resource_limit.limit, modifiers=modifier_ids)
                     )
 
             inventory_config = CppInventoryConfig()