From d376d7a5b0b4fe326c26d07fc958f9993d314d75 Mon Sep 17 00:00:00 2001
From: Josh Holtrop <jholtrop+git@gmail.com>
Date: Wed, 16 Jun 2010 20:51:17 +0000
Subject: [PATCH] fixed AV::Sound::decode() to add sounds and loop over decoded
 length properly

git-svn-id: svn://anubis/anaglym/trunk@280 99a6e188-d820-4881-8870-2d33a10e2619
---
 AV.cc | 50 ++++++++++++++++++++++++++++++++++++++------------
 AV.h  |  2 --
 2 files changed, 38 insertions(+), 14 deletions(-)

diff --git a/AV.cc b/AV.cc
index c5765a2..ad87690 100644
--- a/AV.cc
+++ b/AV.cc
@@ -1,13 +1,22 @@
 
-#include "AV.h"
 #include <GL/gl.h>
 #include <GL/glu.h>
 #include <SDL.h>
-#include <iostream>
 #include <SDL_sound.h>
 #include <math.h>
+#include <limits.h>
+
+#include <iostream>
+
+#include "AV.h"
+
 using namespace std;
 
+#define SOUND_RATE          44100
+#define CALLBACK_SAMPLES    4096
+#define CHANNELS            2
+#define BYTES_PER_SAMPLE    2
+
 void AV_sound_callback(void * userdata, Uint8 * stream, int len)
 {
     ((AV *)userdata)->playCallback(stream, len);
@@ -40,10 +49,10 @@ AV::AV()
 
     Sound_Init();
     SDL_AudioSpec desired;
-    desired.freq = AV_SOUND_RATE;
+    desired.freq = SOUND_RATE;
     desired.format = AUDIO_S16SYS;
-    desired.channels = 2;
-    desired.samples = 4096;
+    desired.channels = CHANNELS;
+    desired.samples = CALLBACK_SAMPLES;
     desired.callback = AV_sound_callback;
     desired.userdata = this;
     if (SDL_OpenAudio(&desired, NULL) < 0)
@@ -130,6 +139,7 @@ void AV::playSound(AV::Sound * s)
 
 void AV::playCallback(Uint8 * stream, int len)
 {
+    memset(stream, 0, len);
     for (std::set<Sound *>::const_iterator it = m_active_sounds.begin();
          it != m_active_sounds.end();
          it++)
@@ -165,8 +175,9 @@ bool AV::Sound::load(FileLoader & fileLoader, const FileLoader::Path & path)
         Sound_AudioInfo desired;
         desired.channels = 2;
         desired.format = AUDIO_S16SYS;
-        desired.rate = AV_SOUND_RATE;
-        m_ss = Sound_NewSample(m_rwops, NULL, &desired, 4192);
+        desired.rate = SOUND_RATE;
+        m_ss = Sound_NewSample(m_rwops, NULL, &desired,
+                CALLBACK_SAMPLES * BYTES_PER_SAMPLE * CHANNELS);
         if (m_ss != NULL)
         {
             return true;
@@ -205,10 +216,25 @@ void AV::Sound::loop(int times)
 
 int AV::Sound::decode(Uint8 * stream, int len)
 {
-    /* TODO: fix for len != m_ss->buffer_size */
-    cerr << "AV::Sound::decode()" << endl;
-    Uint32 len_decoded = Sound_Decode(m_ss);
-    cerr << "AV::Sound::decode() len: " << len << ", len_decoded: " << len_decoded << endl;
-    memcpy(stream, m_ss->buffer, len_decoded);
+    int len_decoded = 0, len_decoded_now;
+    int samples_decoded = 0, samples_decoded_now;
+    int spos = 0;
+    int16_t * s16stream = (int16_t *) stream;
+    int16_t * decoded_stream = (int16_t *) m_ss->buffer;
+    do
+    {
+        len_decoded_now = Sound_Decode(m_ss);
+        samples_decoded_now = len_decoded_now / BYTES_PER_SAMPLE;
+        len_decoded += len_decoded_now;
+        samples_decoded += len_decoded / BYTES_PER_SAMPLE;
+        for (int i = 0; i < samples_decoded_now; i++)
+        {
+            int val = s16stream[spos] + decoded_stream[i];
+            s16stream[spos] = (val > SHRT_MAX) ? SHRT_MAX : val;
+            spos++;
+        }
+    } while ( (len_decoded_now == (int) m_ss->buffer_size)
+           && (len_decoded < len) );
+
     return len_decoded;
 }
diff --git a/AV.h b/AV.h
index a39cfe2..c377fdc 100644
--- a/AV.h
+++ b/AV.h
@@ -10,8 +10,6 @@
 #include "FileLoader/FileLoader.h"
 #include "refptr/refptr.h"
 
-#define AV_SOUND_RATE   44100
-
 class AV
 {
     public: