direct speakers: allow overloading panner for other formats

Author: tomjnixon

ear/core/direct_speakers/panner.py

@@ -1,11 +1,13 @@
 from attr import attrs, attrib, evolve
+from functools import singledispatch
 from multipledispatch import dispatch
 import numpy as np
 import re
 import warnings
 from ..geom import inside_angle_range
 from .. import point_source
 from .. import allocentric
+from ..layout import Layout
 from ..renderer_common import is_lfe
 from ..screen_edge_lock import ScreenEdgeLockHandler
 from ...fileio.adm.elements import DirectSpeakerCartesianPosition, DirectSpeakerPolarPosition
@@ -463,3 +465,13 @@ def handle(self, type_metadata):
             pv = np.zeros(self.n_channels)
             pv[~self.is_lfe] = psp.handle(position)
             return pv
+
+
+@singledispatch
+def build_direct_speakers_panner(layout, **options):
+    return None
+
+
+@build_direct_speakers_panner.register(Layout)
+def _build_direct_speakers_panner_speakers(layout, **options):
+    return DirectSpeakersPanner(layout, **options)

ear/core/direct_speakers/renderer.py

@@ -1,5 +1,5 @@
 import numpy as np
-from .panner import DirectSpeakersPanner
+from .panner import build_direct_speakers_panner
 from ..renderer_common import BlockProcessingChannel, InterpretTimingMetadata, FixedGains
 from ..track_processor import TrackProcessor
 
@@ -44,7 +44,7 @@ class DirectSpeakersRenderer(object):
     """
 
     def __init__(self, layout, **options):
-        self._panner = DirectSpeakersPanner(layout, **options)
+        self._panner = build_direct_speakers_panner(layout, **options)
         self._nchannels = layout.num_channels
 
         # tuples of a track spec processor and a BlockProcessingChannel to