camera iteration #1408

Summary: Use IndexError so that a camera object is an iterable

Reviewed By: shapovalov

Differential Revision: D42312021

fbshipit-source-id: 67c417d5f1398e8b30a6944468eda057b4ceb444

pytorch3d/renderer/cameras.py

@@ -432,7 +432,7 @@ class CamerasBase(TensorProperties):
                     f"Boolean index of shape {index.shape} does not match cameras"
                 )
         elif max(index) >= len(self):
-            raise ValueError(f"Index {max(index)} is out of bounds for select cameras")
+            raise IndexError(f"Index {max(index)} is out of bounds for select cameras")
 
         for field in self._FIELDS:
             val = getattr(self, field, None)

tests/test_cameras.py

@@ -866,6 +866,11 @@ class TestCamerasCommon(TestCaseMixin, unittest.TestCase):
         self.join_cameras_as_batch_fov(FoVOrthographicCameras)
         self.join_cameras_as_batch(OrthographicCameras)
 
+    def test_iterable(self):
+        for camera_type in [PerspectiveCameras, OrthographicCameras]:
+            a_list = list(camera_type())
+            self.assertEqual(len(a_list), 1)
+
 
 ############################################################
 #                FoVPerspective Camera                     #
@@ -1009,7 +1014,7 @@ class TestFoVPerspectiveProjection(TestCaseMixin, unittest.TestCase):
         self.assertClose(c135.R, R_matrix[SLICE, ...])
 
         # Check errors with get item
-        with self.assertRaisesRegex(ValueError, "out of bounds"):
+        with self.assertRaisesRegex(IndexError, "out of bounds"):
             cam[N_CAMERAS]
 
         with self.assertRaisesRegex(ValueError, "does not match cameras"):