Range in parent for transitions (#184)

* Fixed Transition support in otioview.

- Added range_in_parent and trimmed_range_in_parent to Transition.
- Added trim_child_range to Composition.
- Added range_in_parent to Item.

opentimelineio/core/composition.py

@@ -206,9 +206,10 @@ def __deepcopy__(self, md):
         return result
 
     def _path_to_child(self, child):
-        if not isinstance(child, item.Item):
+        if not isinstance(child, composable.Composable):
             raise TypeError(
-                "An object child of 'Item' is required, not type '{}'".format(
+                "An object child of 'Composable' is required,"
+                " not type '{}'".format(
                     type(child)
                 )
             )
@@ -253,8 +254,6 @@ def range_of_child(self, child, reference_space=None):
 
         parents = self._path_to_child(child)
 
-        result_range = child.source_range
-
         current = child
         result_range = None
 
@@ -339,8 +338,6 @@ def trimmed_range_of_child(self, child, reference_space=None):
 
         parents = self._path_to_child(child)
 
-        result_range = child.source_range
-
         current = child
         result_range = None
 
@@ -383,6 +380,34 @@ def trimmed_range_of_child(self, child, reference_space=None):
 
         return opentime.TimeRange(new_start_time, new_duration)
 
+    def trim_child_range(self, child_range):
+        if not self.source_range:
+            return child_range
+
+        # cropped out entirely
+        if (
+            self.source_range.start_time >= child_range.end_time_exclusive()
+            or self.source_range.end_time_exclusive() <= child_range.start_time
+        ):
+            return None
+
+        if child_range.start_time < self.source_range.start_time:
+            child_range = opentime.range_from_start_end_time(
+                self.source_range.start_time,
+                child_range.end_time_exclusive()
+            )
+
+        if (
+            child_range.end_time_exclusive() >
+            self.source_range.end_time_exclusive()
+        ):
+            child_range = opentime.range_from_start_end_time(
+                child_range.start_time,
+                self.source_range.end_time_exclusive()
+            )
+
+        return child_range
+
     # @{ SerializableObject override.
     def update(self, d):
         """Like the dictionary .update() method.

opentimelineio/core/item.py

@@ -118,6 +118,15 @@ def trimmed_range_in_parent(self):
 
         return self.parent().trimmed_range_of_child(self)
 
+    def range_in_parent(self):
+        """Find and return the timmed range of this item in the parent."""
+        if not self.parent():
+            raise exceptions.NotAChildError(
+                "No parent of {}, cannot compute range in parent.".format(self)
+            )
+
+        return self.parent().range_of_child(self)
+
     def transformed_time(self, t, to_item):
         """Converts time t in the coordinate system of self to coordinate
         system of to_item.

opentimelineio/schema/track.py

@@ -92,31 +92,9 @@ def range_of_child_at_index(self, index):
         return opentime.TimeRange(start_time, child.duration())
 
     def trimmed_range_of_child_at_index(self, index, reference_space=None):
-        range = self.range_of_child_at_index(index)
+        child_range = self.range_of_child_at_index(index)
 
-        if not self.source_range:
-            return range
-
-        # cropped out entirely
-        if (
-            self.source_range.start_time >= range.end_time_exclusive()
-            or self.source_range.end_time_exclusive() <= range.start_time
-        ):
-            return None
-
-        if range.start_time < self.source_range.start_time:
-            range = opentime.range_from_start_end_time(
-                self.source_range.start_time,
-                range.end_time_exclusive()
-            )
-
-        if range.end_time_exclusive() > self.source_range.end_time_exclusive():
-            range = opentime.range_from_start_end_time(
-                range.start_time,
-                self.source_range.end_time_exclusive()
-            )
-
-        return range
+        return self.trim_child_range(child_range)
 
     def available_range(self):
         durations = []

opentimelineio/schema/transition.py

@@ -27,6 +27,7 @@
 from .. import (
     opentime,
     core,
+    exceptions,
 )
 
 
@@ -137,3 +138,21 @@ def overlapping():
 
     def duration(self):
         return self.in_offset + self.out_offset
+
+    def range_in_parent(self):
+        """Find and return the range of this item in the parent."""
+        if not self.parent():
+            raise exceptions.NotAChildError(
+                "No parent of {}, cannot compute range in parent.".format(self)
+            )
+
+        return self.parent().range_of_child(self)
+
+    def trimmed_range_in_parent(self):
+        """Find and return the timmed range of this item in the parent."""
+        if not self.parent():
+            raise exceptions.NotAChildError(
+                "No parent of {}, cannot compute range in parent.".format(self)
+            )
+
+        return self.parent().trimmed_range_of_child(self)

tests/test_composition.py

@@ -103,6 +103,61 @@ def test_repr(self):
             ")"
         )
 
+    def test_trim_child_range(self):
+        for st in [
+            otio.schema.Track(name="foo"),
+            otio.schema.Stack(name="foo")
+        ]:
+            st.source_range = otio.opentime.TimeRange(
+                start_time=otio.opentime.RationalTime(value=100, rate=24),
+                duration=otio.opentime.RationalTime(value=50, rate=24)
+            )
+            r = otio.opentime.TimeRange(
+                start_time=otio.opentime.RationalTime(value=110, rate=24),
+                duration=otio.opentime.RationalTime(value=30, rate=24)
+            )
+            self.assertEqual(st.trim_child_range(r), r)
+            r = otio.opentime.TimeRange(
+                start_time=otio.opentime.RationalTime(value=0, rate=24),
+                duration=otio.opentime.RationalTime(value=30, rate=24)
+            )
+            self.assertEqual(st.trim_child_range(r), None)
+            r = otio.opentime.TimeRange(
+                start_time=otio.opentime.RationalTime(value=1000, rate=24),
+                duration=otio.opentime.RationalTime(value=30, rate=24)
+            )
+            self.assertEqual(st.trim_child_range(r), None)
+            r = otio.opentime.TimeRange(
+                start_time=otio.opentime.RationalTime(value=90, rate=24),
+                duration=otio.opentime.RationalTime(value=30, rate=24)
+            )
+            self.assertEqual(
+                st.trim_child_range(r),
+                otio.opentime.TimeRange(
+                    start_time=otio.opentime.RationalTime(value=100, rate=24),
+                    duration=otio.opentime.RationalTime(value=20, rate=24)
+                )
+            )
+            r = otio.opentime.TimeRange(
+                start_time=otio.opentime.RationalTime(value=110, rate=24),
+                duration=otio.opentime.RationalTime(value=50, rate=24)
+            )
+            self.assertEqual(
+                st.trim_child_range(r),
+                otio.opentime.TimeRange(
+                    start_time=otio.opentime.RationalTime(value=110, rate=24),
+                    duration=otio.opentime.RationalTime(value=40, rate=24)
+                )
+            )
+            r = otio.opentime.TimeRange(
+                start_time=otio.opentime.RationalTime(value=90, rate=24),
+                duration=otio.opentime.RationalTime(value=1000, rate=24)
+            )
+            self.assertEqual(
+                st.trim_child_range(r),
+                st.source_range
+            )
+
     def test_range_of_child(self):
         st = otio.schema.Stack(name="foo", children=[
             otio.schema.Clip(