Implement SDL2 audio (again).

UnleashedRecomp/CMakeLists.txt

@@ -137,7 +137,7 @@ set(SWA_APU_CXX_SOURCES
 if (SWA_XAUDIO2)
     list(APPEND SWA_APU_CXX_SOURCES "apu/driver/xaudio_driver.cpp")
 else()
-    list(APPEND SWA_APU_CXX_SOURCES "apu/driver/miniaudio_driver.cpp")
+    list(APPEND SWA_APU_CXX_SOURCES "apu/driver/sdl2_driver.cpp")
 endif()
 
 set(SWA_HID_CXX_SOURCES

UnleashedRecomp/apu/driver/miniaudio_driver.cpp

@@ -1,53 +0,0 @@
-#include "miniaudio_driver.h"
-#include <cpu/code_cache.h>
-#include <cpu/guest_thread.h>
-#include <cpu/guest_code.h>
-#include <kernel/heap.h>
-
-static PPCFunc* g_clientCallback{};
-static uint32_t g_clientCallbackParam{}; // pointer in guest memory
-static ma_device g_audioDevice{};
-static std::unique_ptr<GuestThreadContext> g_audioCtx;
-static uint32_t* g_audioOutput;
-
-static void AudioCallback(ma_device* pDevice, void* pOutput, const void* pInput, ma_uint32 frameCount)
-{
-    if (g_audioCtx == nullptr)
-        g_audioCtx = std::make_unique<GuestThreadContext>(0);
-
-    g_audioCtx->ppcContext.r3.u64 = g_clientCallbackParam;
-    g_audioOutput = reinterpret_cast<uint32_t*>(pOutput);
-    (*g_clientCallback)(g_audioCtx->ppcContext, reinterpret_cast<uint8_t*>(g_memory.base));
-}
-
-void XAudioInitializeSystem()
-{
-    ma_device_config deviceConfig = ma_device_config_init(ma_device_type_playback);
-    deviceConfig.sampleRate = XAUDIO_SAMPLES_HZ;
-    deviceConfig.periodSizeInFrames = XAUDIO_NUM_SAMPLES;
-    deviceConfig.noPreSilencedOutputBuffer = true;
-    deviceConfig.dataCallback = AudioCallback;
-    deviceConfig.playback.format = ma_format_f32;
-    deviceConfig.playback.channels = XAUDIO_NUM_CHANNELS;
-    ma_device_init(nullptr, &deviceConfig, &g_audioDevice);
-}
-
-void XAudioRegisterClient(PPCFunc* callback, uint32_t param)
-{
-    auto* pClientParam = static_cast<uint32_t*>(g_userHeap.Alloc(sizeof(param)));
-    ByteSwapInplace(param);
-    *pClientParam = param;
-    g_clientCallbackParam = g_memory.MapVirtual(pClientParam);
-    g_clientCallback = callback;
-
-    ma_device_start(&g_audioDevice);
-}
-
-void XAudioSubmitFrame(void* samples)
-{
-    for (size_t i = 0; i < XAUDIO_NUM_SAMPLES; i++)
-    {
-        for (size_t j = 0; j < XAUDIO_NUM_CHANNELS; j++)
-            g_audioOutput[i * XAUDIO_NUM_CHANNELS + j] = ByteSwap(((uint32_t*)samples)[j * XAUDIO_NUM_SAMPLES + i]);
-    }
-}

UnleashedRecomp/apu/driver/sdl2_driver.cpp

@@ -0,0 +1,97 @@
+#include "sdl2_driver.h"
+#include <cpu/code_cache.h>
+#include <cpu/guest_thread.h>
+#include <cpu/guest_code.h>
+#include <kernel/heap.h>
+
+static PPCFunc* g_clientCallback{};
+static uint32_t g_clientCallbackParam{}; // pointer in guest memory
+static SDL_AudioDeviceID g_audioDevice{};
+static std::unique_ptr<GuestThreadContext> g_audioCtx;
+static uint32_t* g_audioOutput;
+static bool g_downMixToStereo;
+
+static void AudioCallback(void*, uint8_t* frames, int len)
+{
+    if (g_audioCtx == nullptr)
+        g_audioCtx = std::make_unique<GuestThreadContext>(0);
+
+    g_audioCtx->ppcContext.r3.u64 = g_clientCallbackParam;
+    g_audioOutput = reinterpret_cast<uint32_t*>(frames);
+    (*g_clientCallback)(g_audioCtx->ppcContext, reinterpret_cast<uint8_t*>(g_memory.base));
+}
+
+void XAudioInitializeSystem()
+{
+    SDL_SetHint(SDL_HINT_AUDIO_CATEGORY, "playback");
+    SDL_SetHint(SDL_HINT_AUDIO_DEVICE_APP_NAME, "Unleashed Recompiled");
+    SDL_InitSubSystem(SDL_INIT_AUDIO);
+
+    SDL_AudioSpec desired{}, obtained{};
+    desired.freq = XAUDIO_SAMPLES_HZ;
+    desired.format = AUDIO_F32SYS;
+    desired.channels = XAUDIO_NUM_CHANNELS;
+    desired.samples = XAUDIO_NUM_SAMPLES;
+    desired.callback = AudioCallback;
+    g_audioDevice = SDL_OpenAudioDevice(nullptr, 0, &desired, &obtained, SDL_AUDIO_ALLOW_CHANNELS_CHANGE);
+
+    if (obtained.channels != 2 && obtained.channels != XAUDIO_NUM_CHANNELS)
+    {
+        SDL_CloseAudioDevice(g_audioDevice);
+        g_audioDevice = SDL_OpenAudioDevice(nullptr, 0, &desired, &obtained, 0);
+    }
+
+    g_downMixToStereo = (obtained.channels == 2);
+}
+
+void XAudioRegisterClient(PPCFunc* callback, uint32_t param)
+{
+    auto* pClientParam = static_cast<uint32_t*>(g_userHeap.Alloc(sizeof(param)));
+    ByteSwapInplace(param);
+    *pClientParam = param;
+    g_clientCallbackParam = g_memory.MapVirtual(pClientParam);
+    g_clientCallback = callback;
+
+    SDL_PauseAudioDevice(g_audioDevice, 0);
+}
+
+void XAudioSubmitFrame(void* samples)
+{
+    if (g_downMixToStereo)
+    {
+        // 0: left 1.0f, right 0.0f
+        // 1: left 0.0f, right 1.0f
+        // 2: left 0.75f, right 0.75f
+        // 3: left 0.0f, right 0.0f
+        // 4: left 1.0f, right 0.0f
+        // 5: left 0.0f, right 1.0f
+
+        auto floatSamples = reinterpret_cast<be<float>*>(samples);
+
+        for (size_t i = 0; i < XAUDIO_NUM_SAMPLES; i++)
+        {
+            float ch0 = floatSamples[0 * XAUDIO_NUM_SAMPLES + i];
+            float ch1 = floatSamples[1 * XAUDIO_NUM_SAMPLES + i];
+            float ch2 = floatSamples[2 * XAUDIO_NUM_SAMPLES + i];
+            float ch3 = floatSamples[3 * XAUDIO_NUM_SAMPLES + i];
+            float ch4 = floatSamples[4 * XAUDIO_NUM_SAMPLES + i];
+            float ch5 = floatSamples[5 * XAUDIO_NUM_SAMPLES + i];
+
+            float left  = ch0 + ch2 * 0.75f + ch4;
+            float right = ch1 + ch2 * 0.75f + ch5;
+
+            g_audioOutput[i * 2 + 0] = *reinterpret_cast<uint32_t*>(&left);
+            g_audioOutput[i * 2 + 1] = *reinterpret_cast<uint32_t*>(&right);
+        }
+    }
+    else
+    {
+        auto rawSamples = reinterpret_cast<be<uint32_t>*>(samples);
+
+        for (size_t i = 0; i < XAUDIO_NUM_SAMPLES; i++)
+        {
+            for (size_t j = 0; j < XAUDIO_NUM_CHANNELS; j++)
+                g_audioOutput[i * XAUDIO_NUM_CHANNELS + j] = rawSamples[j * XAUDIO_NUM_SAMPLES + i];
+        }
+    }
+}

UnleashedRecomp/apu/driver/xaudio_driver.cpp

@@ -90,7 +90,7 @@ void XAudioInitializeSystem()
     g_sourceVoice->Start();
 
     KeInsertHostFunction(XAUDIO_DRIVER_KEY, DriverLoop);
-    GuestThread::Start(XAUDIO_DRIVER_KEY, 0, 0, &g_driverThread);
+    GuestThread::Start({ XAUDIO_DRIVER_KEY, 0, 0 }, nullptr);
 }
 
 void XAudioRegisterClient(PPCFunc* callback, uint32_t param)