Python: Experimental audio API

CHANGES

@@ -111,6 +111,7 @@ Features:
  - Qt: State file load/save menu options
  - Windows installer
  - Tile viewer now has adjustable width
+ - Python: Experimental audio API
 Bugfixes:
  - PSP2: Fix audio crackling after fast forward
  - PSP2: Fix audio crackling when buffer is full

src/platform/python/_builder.h

@@ -35,6 +35,7 @@ void free(void*);
 
 #include "flags.h"
 
+#include <mgba/core/blip_buf.h>
 #include <mgba/core/cache-set.h>
 #include <mgba/core/core.h>
 #include <mgba/core/map-cache.h>

src/platform/python/_builder.py

@@ -20,6 +20,7 @@ ffi.set_source("mgba._pylib", """
 #define inline
 #include "flags.h"
 #define OPAQUE_THREADING
+#include <mgba/core/blip_buf.h>
 #include <mgba/core/cache-set.h>
 #include <mgba-util/common.h>
 #include <mgba/core/core.h>

src/platform/python/mgba/audio.py

@@ -0,0 +1,57 @@
+# Copyright (c) 2013-2018 Jeffrey Pfau
+#
+# This Source Code Form is subject to the terms of the Mozilla Public
+# License, v. 2.0. If a copy of the MPL was not distributed with this
+# file, You can obtain one at http://mozilla.org/MPL/2.0/.
+from ._pylib import ffi, lib  # pylint: disable=no-name-in-module
+
+
+class Buffer(object):
+    def __init__(self, native, internal_rate):
+        self._native = native
+        self._internal_rate = internal_rate
+
+    @property
+    def available(self):
+        return lib.blip_samples_avail(self._native)
+
+    def set_rate(self, rate):
+        lib.blip_set_rates(self._native, self._internal_rate, rate)
+
+    def read(self, samples):
+        buffer = ffi.new("short[%i]" % samples)
+        count = self.read_into(buffer, samples, 1, 0)
+        return buffer[:count]
+
+    def read_into(self, buffer, samples, channels=1, interleave=0):
+        return lib.blip_read_samples(self._native, ffi.addressof(buffer, interleave), samples, channels == 2)
+
+    def clear(self):
+        lib.blip_clear(self._native)
+
+
+class StereoBuffer(object):
+    def __init__(self, left, right):
+        self._left = left
+        self._right = right
+
+    @property
+    def available(self):
+        return min(self._left.available, self._right.available)
+
+    def set_rate(self, rate):
+        self._left.set_rate(rate)
+        self._right.set_rate(rate)
+
+    def read(self, samples):
+        buffer = ffi.new("short[%i]" % (2 * samples))
+        count = self.read_into(buffer, samples)
+        return buffer[0:2 * count]
+
+    def read_into(self, buffer, samples):
+        samples = self._left.read_into(buffer, samples, 2, 0)
+        return self._right.read_into(buffer, samples, 2, 1)
+
+    def clear(self):
+        self._left.clear()
+        self._right.clear()

src/platform/python/mgba/core.py

@@ -4,7 +4,7 @@
 # License, v. 2.0. If a copy of the MPL was not distributed with this
 # file, You can obtain one at http://mozilla.org/MPL/2.0/.
 from ._pylib import ffi, lib  # pylint: disable=no-name-in-module
-from . import tile
+from . import tile, audio
 from cached_property import cached_property
 from functools import wraps
 
@@ -225,6 +225,22 @@ class Core(object):
     def set_video_buffer(self, image):
         self._core.setVideoBuffer(self._core, image.buffer, image.stride)
 
+    @protected
+    def set_audio_buffer_size(self, size)
+        self._core.setAudioBufferSize(self._core, size)
+
+    @property
+    def audio_buffer_size(self):
+        return self._core.getAudioBufferSize(self._core)
+
+    @protected
+    def get_audio_channels(self):
+        return audio.StereoBuffer(self.get_audio_channel(0), self.get_audio_channel(1));
+
+    @protected
+    def get_audio_channel(self, channel):
+        return audio.Buffer(self._core.getAudioChannel(self._core, channel), self.frequency)
+
     @protected
     def reset(self):
         self._core.reset(self._core)