From 5298bdefd7f7875ae8b7cb6c9201e3321af62011 Mon Sep 17 00:00:00 2001
From: chai <chaifix@163.com>
Date: Wed, 30 May 2018 08:22:30 +0800
Subject: =?UTF-8?q?=E6=9B=B4=E6=94=B9=E5=9B=9E=E8=B0=83=E5=87=BD=E6=95=B0?=
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---
 src/libjin/audio/sdl/audio.cpp | 34 +++++++++++++++++++++-------------
 1 file changed, 21 insertions(+), 13 deletions(-)

(limited to 'src/libjin/audio/sdl/audio.cpp')

diff --git a/src/libjin/audio/sdl/audio.cpp b/src/libjin/audio/sdl/audio.cpp
index 5277a3d..a26ea1a 100644
--- a/src/libjin/audio/sdl/audio.cpp
+++ b/src/libjin/audio/sdl/audio.cpp
@@ -1,3 +1,4 @@
+#include <iostream>
 #include "audio.h"
 #include "source.h"
 
@@ -6,35 +7,32 @@ namespace jin
 namespace audio
 {
 
-    void SDLAudio::defaultCallback(void *userdata, Uint8 *stream, int size)
+    /* 注意callback是在音频线程调用 */
+    void defaultCallback(void *userdata, Uint8 *stream, int size)
     {
         SDLAudio* audio = (SDLAudio*)userdata;
-        SDL_LockAudioDevice(audio->audioDevice);
+        audio->lock();
         audio->processCommands();
         audio->processSources(stream, size);
-        SDL_UnlockAudioDevice(audio->audioDevice);
+        audio->unlock();
     }
 
     onlyonce bool SDLAudio::_init(const SettingBase* s)
     {
         if (SDL_Init(SDL_INIT_AUDIO) < 0)
             return false;
-        SDLAudioSetting* setting = (SDLAudioSetting*)s;
         SDL_AudioSpec spec;
-        zero(spec);
-        spec.freq = 44100;
-        spec.format = AUDIO_S16SYS;
-        spec.channels = 1;
-        spec.samples = 2048;
+        spec.freq     = 44100;        // 44100 Hz
+        spec.format   = AUDIO_S16SYS; // signed 16bits
+        spec.channels = 2;            // 立体声
+        spec.samples  = 1 << 15;      // Uin16范围内最大的2的幂
         spec.userdata = this;
         spec.callback = defaultCallback;
 
         audioDevice = SDL_OpenAudioDevice(NULL, 0, &spec, NULL, 0); 
         if (audioDevice == 0)
-        {
             return false;
-        }
-        // start audio 
+        /* start audio */
         SDL_PauseAudioDevice(audioDevice, 0);
         return true;
     }
@@ -45,12 +43,22 @@ namespace audio
         delete audio;
     }
 
+    void SDLAudio::lock()
+    {
+        SDL_LockAudioDevice(audioDevice);
+    }
+
+    void SDLAudio::unlock()
+    {
+        SDL_UnlockAudioDevice(audioDevice);
+    }
+
     void SDLAudio::processCommands()
     {
         SDLSourceManager::get()->processCommands();
     }
 
-    void SDLAudio::processSources(Uint8* buffer, int len)
+    void SDLAudio::processSources(void* buffer, size_t len)
     {
         SDLSourceManager::get()->processSources(buffer, len);
     }
-- 
cgit v1.1-26-g67d0