add audio output. HARK HARK HARK

src/CMakeLists.txt

@@ -4,6 +4,7 @@ add_library(core STATIC
 	ARCodeList.cpp
 	AREngine.cpp
 	ARM.cpp
+	ARM_InstrTable.h
 	ARMInterpreter.cpp
 	ARMInterpreter_ALU.cpp
 	ARMInterpreter_Branch.cpp
@@ -12,11 +13,13 @@ add_library(core STATIC
 	CP15.cpp
 	CRC32.cpp
 	DMA.cpp
+	FIFO.h
 	GBACart.cpp
 	GPU.cpp
 	GPU2D.cpp
 	GPU3D.cpp
 	GPU3D_OpenGL.cpp
+	GPU3D_OpenGL_shaders.h
 	GPU3D_Soft.cpp
 	NDS.cpp
 	NDSCart.cpp

src/frontend/FrontendUtil.h

@@ -63,6 +63,19 @@ bool SaveState(const char* filename);
 // undo the latest savestate load
 void UndoStateLoad();
 
+
+// initialize the audio utility
+void Init_Audio(int outputfreq);
+
+// get how many samples to read from the core audio output
+// based on how many are needed by the frontend (outlen in samples)
+int AudioOut_GetNumSamples(int outlen);
+
+// resample audio from the core audio output to match the frontend's
+// output frequency, and apply user-specified volume
+// note: this assumes the output buffer is interleaved stereo
+void AudioOut_Resample(s16* inbuf, int inlen, s16* outbuf, int outlen);
+
 }
 
 #endif // FRONTENDUTIL_H

src/frontend/Util_Audio.cpp

@@ -0,0 +1,77 @@
+/*
+    Copyright 2016-2020 Arisotura
+
+    This file is part of melonDS.
+
+    melonDS is free software: you can redistribute it and/or modify it under
+    the terms of the GNU General Public License as published by the Free
+    Software Foundation, either version 3 of the License, or (at your option)
+    any later version.
+
+    melonDS is distributed in the hope that it will be useful, but WITHOUT ANY
+    WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS
+    FOR A PARTICULAR PURPOSE. See the GNU General Public License for more details.
+
+    You should have received a copy of the GNU General Public License along
+    with melonDS. If not, see http://www.gnu.org/licenses/.
+*/
+
+#include <stdio.h>
+#include <string.h>
+#include <math.h>
+
+#include "FrontendUtil.h"
+#include "Config.h"
+#include "qt_sdl/PlatformConfig.h" // FIXME!!!
+#include "Platform.h"
+
+#include "NDS.h"
+#include "GBACart.h"
+
+
+namespace Frontend
+{
+
+int AudioOut_Freq;
+float AudioOut_SampleFrac;
+
+
+void Init_Audio(int outputfreq)
+{
+    AudioOut_Freq = outputfreq;
+    AudioOut_SampleFrac = 0;
+}
+
+int AudioOut_GetNumSamples(int outlen)
+{
+    float f_len_in = (outlen * 32823.6328125) / (float)AudioOut_Freq;
+    f_len_in += AudioOut_SampleFrac;
+    int len_in = (int)floor(f_len_in);
+    AudioOut_SampleFrac = f_len_in - len_in;
+
+    return len_in;
+}
+
+void AudioOut_Resample(s16* inbuf, int inlen, s16* outbuf, int outlen)
+{
+    float res_incr = inlen / (float)outlen;
+    float res_timer = 0;
+    int res_pos = 0;
+
+    int volume = Config::AudioVolume;
+
+    for (int i = 0; i < outlen; i++)
+    {
+        outbuf[i*2  ] = (inbuf[res_pos*2  ] * volume) >> 8;
+        outbuf[i*2+1] = (inbuf[res_pos*2+1] * volume) >> 8;
+
+        res_timer += res_incr;
+        while (res_timer >= 1.0)
+        {
+            res_timer -= 1.0;
+            res_pos++;
+        }
+    }
+}
+
+}

src/frontend/qt_sdl/CMakeLists.txt

@@ -6,6 +6,7 @@ SET(SOURCES_QT_SDL
 	PlatformConfig.cpp
 	
 	../Util_ROM.cpp
+	../Util_Audio.cpp
 	../FrontendUtil.h
 )
 

src/frontend/qt_sdl/main.cpp

@@ -48,6 +48,8 @@
 #include "Savestate.h"
 
 
+// TODO: uniform variable spelling
+
 char* EmuDirectory;
 
 bool RunningSomething;
@@ -55,6 +57,48 @@ bool RunningSomething;
 MainWindow* mainWindow;
 EmuThread* emuThread;
 
+SDL_AudioDeviceID audioDevice;
+int audioFreq;
+SDL_cond* audioSync;
+SDL_mutex* audioSyncLock;
+
+
+void audioCallback(void* data, Uint8* stream, int len)
+{
+    len /= (sizeof(s16) * 2);
+
+    // resample incoming audio to match the output sample rate
+
+    int len_in = Frontend::AudioOut_GetNumSamples(len);
+    s16 buf_in[1024*2];
+    int num_in;
+
+    SDL_LockMutex(audioSyncLock);
+    num_in = SPU::ReadOutput(buf_in, len_in);
+    SDL_CondSignal(audioSync);
+    SDL_UnlockMutex(audioSyncLock);
+
+    if (num_in < 1)
+    {
+        memset(stream, 0, len*sizeof(s16)*2);
+        return;
+    }
+
+    int margin = 6;
+    if (num_in < len_in-margin)
+    {
+        int last = num_in-1;
+        if (last < 0) last = 0;
+
+        for (int i = num_in; i < len_in-margin; i++)
+            ((u32*)buf_in)[i] = ((u32*)buf_in)[last];
+
+        num_in = len_in-margin;
+    }
+
+    Frontend::AudioOut_Resample(buf_in, num_in, (s16*)stream, len);
+}
+
 
 EmuThread::EmuThread(QObject* parent) : QThread(parent)
 {
@@ -213,18 +257,18 @@ void EmuThread::run()
             mainWindow->update();
 
             bool fastforward = false;
-            /*bool fastforward = HotkeyDown(HK_FastForward);
+            //bool fastforward = HotkeyDown(HK_FastForward);
 
-            if (Config::AudioSync && !fastforward)
+            if (Config::AudioSync && (!fastforward) && audioDevice)
             {
-                SDL_LockMutex(AudioSyncLock);
+                SDL_LockMutex(audioSyncLock);
                 while (SPU::GetOutputSize() > 1024)
                 {
-                    int ret = SDL_CondWaitTimeout(AudioSync, AudioSyncLock, 500);
+                    int ret = SDL_CondWaitTimeout(audioSync, audioSyncLock, 500);
                     if (ret == SDL_MUTEX_TIMEDOUT) break;
                 }
-                SDL_UnlockMutex(AudioSyncLock);
+                SDL_UnlockMutex(audioSyncLock);
-            }*/
+            }
 
             float framerate = (1000.0f * nlines) / (60.0f * 263.0f);
 
@@ -338,6 +382,7 @@ void EmuThread::emuRun()
 
     // checkme
     emit windowEmuStart();
+    if (audioDevice) SDL_PauseAudioDevice(audioDevice, 0);
 }
 
 void EmuThread::emuPause(bool refresh)
@@ -348,6 +393,7 @@ void EmuThread::emuPause(bool refresh)
     while (EmuStatus != status);
 
     //emit windowEmuPause();
+    if (audioDevice) SDL_PauseAudioDevice(audioDevice, 1);
 }
 
 void EmuThread::emuUnpause()
@@ -355,11 +401,14 @@ void EmuThread::emuUnpause()
     EmuRunning = PrevEmuStatus;
 
     //emit windowEmuUnpause();
+    if (audioDevice) SDL_PauseAudioDevice(audioDevice, 0);
 }
 
 void EmuThread::emuStop()
 {
     EmuRunning = 0;
+
+    if (audioDevice) SDL_PauseAudioDevice(audioDevice, 1);
 }
 
 bool EmuThread::emuIsRunning()
@@ -908,6 +957,32 @@ int main(int argc, char** argv)
     }
 #endif
 
+    audioSync = SDL_CreateCond();
+    audioSyncLock = SDL_CreateMutex();
+
+    audioFreq = 48000; // TODO: make configurable?
+    SDL_AudioSpec whatIwant, whatIget;
+    memset(&whatIwant, 0, sizeof(SDL_AudioSpec));
+    whatIwant.freq = audioFreq;
+    whatIwant.format = AUDIO_S16LSB;
+    whatIwant.channels = 2;
+    whatIwant.samples = 1024;
+    whatIwant.callback = audioCallback;
+    audioDevice = SDL_OpenAudioDevice(NULL, 0, &whatIwant, &whatIget, SDL_AUDIO_ALLOW_FREQUENCY_CHANGE);
+    if (!audioDevice)
+    {
+        printf("Audio init failed: %s\n", SDL_GetError());
+    }
+    else
+    {
+        audioFreq = whatIget.freq;
+        printf("Audio output frequency: %d Hz\n", audioFreq);
+        SDL_PauseAudioDevice(audioDevice, 1);
+    }
+
+    Frontend::Init_ROM();
+    Frontend::Init_Audio(audioFreq);
+
     mainWindow = new MainWindow();
     mainWindow->show();
 
@@ -955,6 +1030,15 @@ int main(int argc, char** argv)
     emuThread->emuStop();
     emuThread->wait();
 
+    //if (Joystick) SDL_JoystickClose(Joystick);
+    if (audioDevice) SDL_CloseAudioDevice(audioDevice);
+    //if (MicDevice)   SDL_CloseAudioDevice(MicDevice);
+
+    SDL_DestroyCond(audioSync);
+    SDL_DestroyMutex(audioSyncLock);
+
+    //if (MicWavBuffer) delete[] MicWavBuffer;
+
     Config::Save();
 
     SDL_Quit();