Use a single environment variable to find both models and meshes

README.md

@@ -44,16 +44,23 @@ Only GNU/Linux distributions are currently supported.
 
 #### Standalone usage
 
-If you use Ignition Gazebo, you need to execute the following commands (from outside the directory where you cloned this repository):
+If you use Ignition Gazebo, you need to specify where the models and their dependent resources are located in the filesystem.
+The simulator reads the `IGN_GAZEBO_RESOURCE_PATH` environment variable.
+
+Execute the following commands from outside the directory where you cloned this repository to temporarily configure your environment:
 
 ```sh
 PKG_DIR=$(python -c "import gym_ignition_models, inspect, os; print(os.path.dirname(inspect.getfile(gym_ignition_models)))")
-export SDF_PATH=$PKG_DIR:SDF_PATH
+export IGN_GAZEBO_RESOURCE_PATH=$PKG_DIR:$IGN_GAZEBO_RESOURCE_PATH
 ```
 
 If you want to make this change persistent, add the lines above to your `~/.bashrc`.
 
-**Note:** waiting an [upstream fix](https://bitbucket.org/osrf/sdformat/issues/227/error-loading-meshes-from-a-relative), you also need to add to the `IGN_FILE_PATH` environment variable all the directories that contain model's meshes.
+**Note:** waiting an [upstream fix](https://github.com/osrf/sdformat/issues/227), you also need to add
+to `IGN_GAZEBO_RESOURCE_PATH` all the directories containing model's meshes.
+
+**Note:** Alternatively, instead of using `IGN_GAZEBO_RESOURCE_PATH`, you can use `SDF_PATH` for the models and
+`IGN_FILE_PATH` for the meshes.
 
 #### Python usage
 

gym_ignition_models/__init__.py

@@ -94,10 +94,10 @@ def setup_environment() -> None:
         raise NotADirectoryError(f"Failed to find path '{models_path}'")
 
     # Setup the environment to find the models
-    if "SDF_PATH" in os.environ:
-        os.environ["SDF_PATH"] += f":{models_path}"
+    if "IGN_GAZEBO_RESOURCE_PATH" in os.environ:
+        os.environ["IGN_GAZEBO_RESOURCE_PATH"] += f":{models_path}"
     else:
-        os.environ["SDF_PATH"] = f"{models_path}"
+        os.environ["IGN_GAZEBO_RESOURCE_PATH"] = f"{models_path}"
 
     # Models with mesh files
     # Workaround for https://github.com/osrf/sdformat/issues/227
@@ -111,10 +111,10 @@ def setup_environment() -> None:
         if not model_path.exists():
             raise NotADirectoryError(f"Failed to find path '{model_path}'")
 
-        if "IGN_FILE_PATH" in os.environ:
-            os.environ["IGN_FILE_PATH"] += f':{model_path}'
+        if "IGN_GAZEBO_RESOURCE_PATH" in os.environ:
+            os.environ["IGN_GAZEBO_RESOURCE_PATH"] += f':{model_path}'
         else:
-            os.environ["IGN_FILE_PATH"] = f'{model_path}'
+            os.environ["IGN_GAZEBO_RESOURCE_PATH"] = f'{model_path}'
 
 
 # Setup the environment when the package is imported