Fix sound issues in the GB Camera ROM

- The ROM takes lots of captures during boot, which slows down emulation. This commit adds a cooldown counter. - Audio was delayed when the game actually started because the boot code was sending too many samples to the SDL AudioStream buffer. This commit adds code to clear this buffer when it gets too big.
AntonioND · Dec 30, 2020 · 21e435b · 21e435b
1 parent 9f18731
commit 21e435b
Show file tree

Hide file tree

Showing 5 changed files with 41 additions and 5 deletions.
diff --git a/source/gb_core/camera.c b/source/gb_core/camera.c
@@ -37,9 +37,21 @@ int GB_CameraInit(void)
     return Webcam_Init();
 }
 
+static int webcam_frame_delay = 0;
+
 void GB_CameraWebcamCapture(void)
 {
-    Webcam_GetFrame();
+    if (webcam_frame_delay == 0)
+    {
+        Webcam_GetFrame();
+        webcam_frame_delay = 5;
+    }
+}
+
+void GB_CameraWebcamDelayDecrease(void)
+{
+    if (webcam_frame_delay > 0)
+        webcam_frame_delay--;
 }
 
 //----------------------------------------------------------------

diff --git a/source/gb_core/camera.h b/source/gb_core/camera.h
@@ -33,6 +33,8 @@ void GB_CameraWriteRegister(int address, int value);
 // Returns 1 if mapper is the GB Camera
 int GB_MapperIsGBCamera(void);
 
+void GB_CameraWebcamDelayDecrease(void);
+
 //----------------------------------------------------------------
 
 void GB_CameraClockCounterReset(void);

diff --git a/source/gui/win_main.c b/source/gui/win_main.c
@@ -1498,7 +1498,11 @@ void Win_MainLoopHandle(void)
             {
                 size_t size = GBA_SoundGetSamplesFrame(samples, sizeof(samples));
 
-                if (Sound_IsBufferOverThreshold())
+                if (Sound_IsBufferTooBig())
+                {
+                    Sound_ClearBuffer();
+                }
+                else if (Sound_IsBufferOverThreshold())
                 {
                     if (size > 8) // This should always be true
                         size -= 8;
@@ -1527,6 +1531,7 @@ void Win_MainLoopHandle(void)
             {
                 Input_Update_GB();
                 GB_RunForOneFrame();
+                GB_CameraWebcamDelayDecrease();
             }
 
             if (_win_main_has_to_frameskip() == 0)
@@ -1541,7 +1546,11 @@ void Win_MainLoopHandle(void)
             {
                 size_t size = GB_SoundGetSamplesFrame(samples, sizeof(samples));
 
-                if (Sound_IsBufferOverThreshold())
+                if (Sound_IsBufferTooBig())
+                {
+                    Sound_ClearBuffer();
+                }
+                else if (Sound_IsBufferOverThreshold())
                 {
                     if (size > 8) // This should always be true
                         size -= 8;

diff --git a/source/sound_utils.c b/source/sound_utils.c
@@ -70,6 +70,11 @@ static void Sound_Callback(unused__ void *userdata, Uint8 *buffer, int len)
     }
 }
 
+void Sound_ClearBuffer(void)
+{
+    SDL_AudioStreamClear(stream);
+}
+
 static void Sound_End(void)
 {
      SDL_FreeAudioStream(stream);
@@ -122,6 +127,14 @@ int Sound_IsBufferOverThreshold(void)
     return 0;
 }
 
+int Sound_IsBufferTooBig(void)
+{
+    if (SDL_AudioStreamAvailable(stream) > SDL_BUFFER_SAMPLES_THRESHOLD * 2)
+        return 1;
+
+    return 0;
+}
+
 void Sound_SendSamples(int16_t *buffer, int len)
 {
     int rc = SDL_AudioStreamPut(stream, buffer, len);

diff --git a/source/sound_utils.h b/source/sound_utils.h
@@ -11,14 +11,14 @@
 #define GBA_SAMPLERATE      (32 * 1024)
 #define SDL_SAMPLERATE      (44100)
 
-typedef void(Sound_CallbackPointer)(void *, long);
-
 void Sound_Init(void);
 
 void Sound_Enable(void);
 void Sound_Disable(void);
 
+void Sound_ClearBuffer(void);
 int Sound_IsBufferOverThreshold(void);
+int Sound_IsBufferTooBig(void);
 void Sound_SendSamples(int16_t *buffer, int len);
 
 void Sound_SetVolume(int vol);