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DirectSound: Refactor the playback-only implementation.

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This commit is contained in:
David Reid
2019-03-03 12:50:33 +10:00
parent 74c22ad77f
commit 2660dd5fcb
1 changed files with 100 additions and 1 deletions
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mini_al.h
+100 -1
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@@ -9847,7 +9847,106 @@ mal_result mal_device_main_loop__dsound(mal_device* pDevice)
case mal_device_type_playback:
{
/* Not yet implemented. */
DWORD availableBytesPlayback;
DWORD physicalPlayCursorInBytes;
DWORD physicalWriteCursorInBytes;
if (FAILED(mal_IDirectSoundBuffer_GetCurrentPosition((mal_IDirectSoundBuffer*)pDevice->dsound.pPlaybackBuffer, &physicalPlayCursorInBytes, &physicalWriteCursorInBytes))) {
break;
}
if (physicalPlayCursorInBytes < prevPlayCursorInBytesPlayback) {
physicalPlayCursorLoopFlagPlayback = !physicalPlayCursorLoopFlagPlayback;
}
prevPlayCursorInBytesPlayback = physicalPlayCursorInBytes;
/* If there's any bytes available for writing we can do that now. The space between the virtual cursor position and play cursor. */
if (physicalPlayCursorLoopFlagPlayback == virtualWriteCursorLoopFlagPlayback) {
/* Same loop iteration. The available bytes wraps all the way around from the virtual write cursor to the physical play cursor. */
if (physicalPlayCursorInBytes <= virtualWriteCursorInBytesPlayback) {
availableBytesPlayback = (pDevice->playback.internalBufferSizeInFrames*bpfPlayback) - virtualWriteCursorInBytesPlayback;
availableBytesPlayback += physicalPlayCursorInBytes; /* Wrap around. */
} else {
/* This is an error. */
#ifdef MAL_DEBUG_OUTPUT
printf("[DirectSound] (Playback) WARNING: Play cursor has moved in front of the write cursor (same loop iterations). physicalPlayCursorInBytes=%d, virtualWriteCursorInBytes=%d.\n", physicalPlayCursorInBytes, virtualWriteCursorInBytesPlayback);
#endif
availableBytesPlayback = 0;
}
} else {
/* Different loop iterations. The available bytes only goes from the virtual write cursor to the physical play cursor. */
if (physicalPlayCursorInBytes >= virtualWriteCursorInBytesPlayback) {
availableBytesPlayback = physicalPlayCursorInBytes - virtualWriteCursorInBytesPlayback;
} else {
/* This is an error. */
#ifdef MAL_DEBUG_OUTPUT
printf("[DirectSound] (Playback) WARNING: Write cursor has moved behind the play cursor (different loop iterations). physicalPlayCursorInBytes=%d, virtualWriteCursorInBytes=%d.\n", physicalPlayCursorInBytes, virtualWriteCursorInBytesPlayback);
#endif
availableBytesPlayback = 0;
}
}
#ifdef MAL_DEBUG_OUTPUT
printf("[DirectSound] (Playback) physicalPlayCursorInBytes=%d, availableBytesPlayback=%d\n", physicalPlayCursorInBytes, availableBytesPlayback);
#endif
/* If there's no room available for writing we need to wait for more. */
if (availableBytesPlayback == 0) {
mal_sleep(waitTimeInMilliseconds);
continue;
}
/* Getting here means there room available somewhere. We limit this to either the end of the buffer or the physical play cursor, whichever is closest. */
lockOffsetInBytesPlayback = virtualWriteCursorInBytesPlayback;
if (physicalPlayCursorLoopFlagPlayback == virtualWriteCursorLoopFlagPlayback) {
/* Same loop iteration. Go up to the end of the buffer. */
lockSizeInBytesPlayback = (pDevice->playback.internalBufferSizeInFrames*bpfPlayback) - virtualWriteCursorInBytesPlayback;
} else {
/* Different loop iterations. Go up to the physical play cursor. */
lockSizeInBytesPlayback = physicalPlayCursorInBytes - virtualWriteCursorInBytesPlayback;
}
hr = mal_IDirectSoundBuffer_Lock((mal_IDirectSoundBuffer*)pDevice->dsound.pPlaybackBuffer, lockOffsetInBytesPlayback, lockSizeInBytesPlayback, &pMappedBufferPlayback, &mappedSizeInBytesPlayback, NULL, NULL, 0);
if (FAILED(hr)) {
result = mal_post_error(pDevice, MAL_LOG_LEVEL_ERROR, "[DirectSound] Failed to map buffer from playback device in preparation for writing to the device.", MAL_FAILED_TO_MAP_DEVICE_BUFFER);
break;
}
/*
At this point we have a buffer for output. If we don't need to do any data conversion we can pass the mapped pointer to the buffer directly. Otherwise
we need to convert the data.
*/
if (pDevice->playback.converter.isPassthrough) {
/* Passthrough. */
pDevice->onData(pDevice, pMappedBufferPlayback, NULL, (mappedSizeInBytesPlayback/bpfPlayback));
} else {
/* Conversion. */
mal_device__read_frames_from_client(pDevice, (mappedSizeInBytesPlayback/bpfPlayback), pMappedBufferPlayback);
}
hr = mal_IDirectSoundBuffer_Unlock((mal_IDirectSoundBuffer*)pDevice->dsound.pPlaybackBuffer, pMappedBufferPlayback, mappedSizeInBytesPlayback, NULL, 0);
if (FAILED(hr)) {
result = mal_post_error(pDevice, MAL_LOG_LEVEL_ERROR, "[DirectSound] Failed to unlock internal buffer from playback device after writing to the device.", MAL_FAILED_TO_UNMAP_DEVICE_BUFFER);
break;
}
virtualWriteCursorInBytesPlayback += mappedSizeInBytesPlayback;
if (virtualWriteCursorInBytesPlayback == pDevice->playback.internalBufferSizeInFrames*bpfPlayback) {
virtualWriteCursorInBytesPlayback = 0;
virtualWriteCursorLoopFlagPlayback = !virtualWriteCursorLoopFlagPlayback;
}
/*
We may need to start the device. We want two full periods to be written before starting the playback device. Having an extra period adds
a bit of a buffer to prevent the playback buffer from getting starved.
*/
framesWrittenToPlaybackDevice += mappedSizeInBytesPlayback/bpfPlayback;
if (!isPlaybackDeviceStarted && framesWrittenToPlaybackDevice >= (pDevice->playback.internalBufferSizeInFrames/pDevice->playback.internalPeriods)) {
if (FAILED(mal_IDirectSoundBuffer_Play((mal_IDirectSoundBuffer*)pDevice->dsound.pPlaybackBuffer, 0, 0, MAL_DSBPLAY_LOOPING))) {
mal_IDirectSoundCaptureBuffer_Stop((mal_IDirectSoundCaptureBuffer*)pDevice->dsound.pCaptureBuffer);
return mal_post_error(pDevice, MAL_LOG_LEVEL_ERROR, "[DirectSound] IDirectSoundBuffer_Play() failed.", MAL_FAILED_TO_START_BACKEND_DEVICE);
}
isPlaybackDeviceStarted = MAL_TRUE;
}
} break;