ENH: Hacky mixin to make surface CaretDataFiles implement TriangularMesh

Author: effigies

nibabel/cifti2/caretspec.py

@@ -18,8 +18,12 @@
 
 """
 import xml.etree.ElementTree as et
-from ..caret import CaretMetaData
-from .. import xmlutils as xml
+from urllib.parse import urlparse
+
+import nibabel as nb
+from nibabel.caret import CaretMetaData
+from nibabel import xmlutils as xml
+from nibabel import pointset as ps
 
 
 class CaretSpecDataFile(xml.XmlSerializable):
@@ -55,6 +59,9 @@ def __init__(self, structure=None, data_file_type=None, selected=None, uri=None)
         self.selected = selected
         self.uri = uri
 
+        if data_file_type == 'SURFACE':
+            self.__class__ = SurfaceDataFile
+
     def _to_xml_element(self):
         data_file = xml.Element('DataFile')
         data_file.attrib['Structure'] = str(self.structure)
@@ -67,6 +74,35 @@ def __repr__(self):
         return self.to_xml().decode()
 
 
+class SurfaceDataFile(ps.TriangularMesh, CaretSpecDataFile):
+    _gifti = None
+    _coords = None
+    _triangles = None
+
+    def _get_gifti(self):
+        if self._gifti is None:
+            parts = urlparse(self.uri)
+            if parts.scheme == "file":
+                self._gifti = nb.load(parts.path)
+            elif parts.scheme == "":
+                self._gifti = nb.load(self.uri)
+            else:
+                self._gifti = nb.GiftiImage.from_url(self.uri)
+        return self._gifti
+
+    def get_triangles(self, name=None):
+        if self._triangles is None:
+            gifti = self._get_gifti()
+            self._triangles = gifti.agg_data('triangle')
+        return self._triangles
+
+    def get_coords(self, name=None):
+        if self._coords is None:
+            gifti = self._get_gifti()
+            self._coords = gifti.agg_data('pointset')
+        return self._coords
+
+
 class CaretSpecFile(xml.XmlSerializable):
     """ Class for CaretSpecFile XML documents