Merge pull request #242 from arpastrana/master

Pull Request for handling mesh loading from URDFs

Author: gonzalocasas

AUTHORS.md

@@ -16,3 +16,4 @@
 
 - Kathrin Dörfler <<doerfler@arch.ethz.ch>> [@Kathrin3010](https://github.com/Kathrin3010)
 - Robin Oval <<oval@arch.ethz.ch>> [@robin-oval](https://github.com/robin-oval)
+- Rafael Pastrana <<pastrana@arch.ethz.ch>> [@arpastrana](https://github.com/arpastrana)

src/compas/robots/resources/basic.py

@@ -9,7 +9,7 @@
 __all__ = [
     'AbstractMeshLoader',
     'DefaultMeshLoader',
-    'LocalPackageMeshLoader',
+    'LocalPackageMeshLoader'
 ]
 
 try:
@@ -55,12 +55,34 @@ def load_mesh(self, url):
 
 
 class DefaultMeshLoader(AbstractMeshLoader):
-    """Handles basic mesh loader tasks, mostly from local files."""
+    """Handles basic mesh loader tasks, mostly from local files.
 
-    def __init__(self):
+    Attributes
+    ----------
+    kwargs (optional): dict
+        Additional keyword arguments.
+    """
+
+    def __init__(self, **kwargs):
         super(DefaultMeshLoader, self).__init__()
+        self.attr = kwargs or dict()
 
     def can_load_mesh(self, url):
+        """Determine whether this loader can load a given mesh URL.
+
+        Parameters
+        ----------
+        url : str
+            Mesh URL.
+
+        Returns
+        -------
+        bool
+            ``True`` if the URL points to a local and valid file.
+            Otherwise ``False``.
+        """
+
+        url = self._get_mesh_url(url)
         scheme = urlparse(url).scheme
 
         # Local files have either:
@@ -70,18 +92,52 @@ def can_load_mesh(self, url):
         is_local_file = len(scheme) in (0, 1) or scheme == 'file'
 
         if is_local_file:
-            return True
+            if os.path.isfile(url):
+                return True
 
         # Only OBJ loader supports remote files atm
         is_obj = _get_file_format(url) == 'obj'
         return scheme in ('http', 'https') and is_obj
 
     def load_mesh(self, url):
-        if url.startswith('file:///'):
-            url = url[8:]
+        """Loads a mesh from local storage.
 
+        Parameters
+        ----------
+        url : str
+            Mesh location
+
+        Returns
+        -------
+        :class:`Mesh`
+            Instance of a mesh.
+        """        
+        url = self._get_mesh_url(url)
         return _mesh_import(url, url)
 
+    def _get_mesh_url(self, url):
+        """Concatenates basepath directory to URL only if defined in the keyword arguments.
+        It also strips out the scheme 'file:///' from the URL if present.
+
+        Parameters
+        ----------
+        url : str
+            Mesh location.
+
+        Returns
+        -------
+        url: str
+            Extended mesh url location if basepath in kwargs. 
+            Else, it returns url. 
+        """
+        if url.startswith('file:///'):
+            url = url[8:]
+        
+        basepath = self.attr.get('basepath') 
+        if basepath:
+            return os.path.join(basepath, url)
+        return url
+
 
 def _get_file_format(url):
     # This could be much more elaborate