AUDCLNT_STREAMFLAGS_AUTOCONVERTPCM is required in order to allow for sample rates other than the system mixer configured sample rate. Otherwise, WASAPI is limited to a single system configured sample rate in Shared mode, which is a severe limitation compared to other APIs supported by PortAudio.
AUDCLNT_STREAMFLAGS_SRC_DEFAULT_QUALITY is recommended to be used additionally.
See <https://docs.microsoft.com/en-us/windows/desktop/coreaudio/audclnt-streamflags-xxx-constants> for documentation.
GetClosestFormat is modified to exit early when paWinWasapiAutoConvert is set in Shared mode because we trust the WASAPI conversions to succeed.
We restrict these changes to Windows 7 (and later) because documentation does not clearly state the minimum required Windows version. Windows Vista was not available for testing.
This patch has been in production in OpenMPT (<https://openmpt.org/>) since version 1.27.01.00 (2017-09-27). PortAudio WASAPI Shared mode is the default output device type in OpenMPT for Windows 7 (and later) and also for Wine setups.
Currently the CMake build system goes through complicated logic to
find the DirectX SDK. This is completely unnecessary, because modern
versions of the Windows SDK include dsound.h and dsound.lib in the
standard paths, so it can be treated just like the other Windows OS
libraries and we can safely assume it is available.
This commit simplifies the logic and will allow the vcpkg portaudio
port to align with portaudio stream, by getting rid of this patch:
95f9ce56f3/ports/portaudio/find_dsound.patch
I have verified that PortAudio CMake still builds with this commit
with the following toolchains:
- Windows Visual Studio 2017 native CMake support
- mingw-w64 on Windows (msys2)
- mingw-w64 cross-compiling from Debian Unstable
- support for explicit 8.24 format (24-bit inside 32-bit container) by specifying paCustomFormat (see IMPORTANT notes in the header file);
- new flag paWinWasapiExplicitSampleFormat to force explicit format and avoid fallback to a closest working;
- new function PaWasapi_GetDeviceCurrentFormat to get device format of the opened stream;
- support PaWasapi_ThreadPriorityXXX API on UWP to boot thread priority;
- improved selection of the closest format in Exclusive mode.
wasapi: new WASAPI specific API PaWasapi_UpdateDeviceList() which allows to update WASAPI device list dynamically without a need to call Pa_Terminate() and then Pa_Initialize()
Merged-on: https://assembla.com/code/portaudio/git/merge_requests/6241053
This new implementation overcomes current limitation of Pa_GetDeviceCount() API which gives constant device count by making WASAPI device list constant (32 devices by default) where 32 device slots can either be filled with a real device info or be empty for a future device changes.
Constant device list size can be altered by PA_WASAPI_MAX_CONST_DEVICE_COUNT define during a compile time. If PA_WASAPI_MAX_CONST_DEVICE_COUNT is set to 0 then PaWasapi_UpdateDeviceList() will be unavailable as well as dynamic device list update functionality.
This implementation also detects the audio device format change if user alters it via Windows Audio Controller GUI.
This implementation also makes WASAPI backend ready for a future implementation of device list updates via PortAudio public API. See internal PaError UpdateDeviceList().
wasapi: use IAudioClient3 for Windows 10 for best compatibility
wasapi: fix compilation when Windows 10 SDK (10.0.15063.0) is used by removing SignalObjectAndWait() definition which creates duplicates with the system defined SignalObjectAndWait() (since 10.0.15063.0 it is supported by the OS again)
