From 68988ab93cb685c8b4b87cba0d339634a42af8cf Mon Sep 17 00:00:00 2001
From: Chris Robinson <chris.kcat@gmail.com>
Date: Sun, 30 Jun 2013 08:16:49 -0700
Subject: [PATCH] Handle S8 and U16 samples from SDL_sound

---
 src/sound/oalsdlsound.cpp | 72 ++++++++++++++++++++++++++++++++++++---
 src/sound/oalsdlsound.h   |  4 +++
 2 files changed, 72 insertions(+), 4 deletions(-)

diff --git a/src/sound/oalsdlsound.cpp b/src/sound/oalsdlsound.cpp
index 6e704cddc..d0fb88a2f 100644
--- a/src/sound/oalsdlsound.cpp
+++ b/src/sound/oalsdlsound.cpp
@@ -182,7 +182,8 @@ bool OpenALSoundStream::SetupSource()
 OpenALSoundStream::OpenALSoundStream(OpenALSoundRenderer *renderer)
     : Renderer(renderer), Sample(NULL), Source(0), Playing(false),
       Looping(false), Buffers(4), SampleRate(0), Format(0),
-      NeedSwab(false), Volume(1.f)
+      NeedSwab(false), NeedS8Conv(false), NeedS16Conv(false),
+      Volume(1.f)
 {
     for(size_t i = 0;i < Buffers.size();i++)
         Buffers[i] = 0;
@@ -328,6 +329,19 @@ void *OpenALSoundStream::GetData(size_t bytes)
             *(samples++) = ((smp>>8)&0x00FF) | ((smp<<8)*0xFF00);
         }
     }
+    if(NeedS8Conv)
+    {
+        char *samples = reinterpret_cast<char*>(data);
+        for(size_t i = 0;i < bytes;i++)
+            samples[i] = samples[i]^0x80;
+    }
+    if(NeedS16Conv)
+    {
+        short *samples = reinterpret_cast<short*>(data);
+        size_t count = bytes >> 1;
+        for(size_t i = 0;i < count;i++)
+            samples[i] = samples[i]^0x8000;
+    }
     return data;
 }
 
@@ -337,7 +351,16 @@ bool OpenALSoundStream::InitSample()
     SampleRate = Sample->actual.rate;
 
     Format = AL_NONE;
-    if(Sample->actual.format == AUDIO_U8)
+    if(Sample->actual.format == AUDIO_S8)
+    {
+        NeedS8Conv = true;
+        if(Sample->actual.channels == 1)
+            Format = AL_FORMAT_MONO8;
+        else if(Sample->actual.channels == 2)
+            Format = AL_FORMAT_STEREO8;
+        smpsize = 1 * Sample->actual.channels;
+    }
+    else if(Sample->actual.format == AUDIO_U8)
     {
         if(Sample->actual.channels == 1)
             Format = AL_FORMAT_MONO8;
@@ -354,6 +377,16 @@ bool OpenALSoundStream::InitSample()
             Format = AL_FORMAT_STEREO16;
         smpsize = 1 * Sample->actual.channels;
     }
+    else if(Sample->actual.format == AUDIO_U16LSB || Sample->actual.format == AUDIO_U16MSB)
+    {
+        NeedS16Conv = true;
+        NeedSwab = (Sample->actual.format != AUDIO_U16SYS);
+        if(Sample->actual.channels == 1)
+            Format = AL_FORMAT_MONO16;
+        else if(Sample->actual.channels == 2)
+            Format = AL_FORMAT_STEREO16;
+        smpsize = 1 * Sample->actual.channels;
+    }
 
     if(Format == AL_NONE)
     {
@@ -426,7 +459,7 @@ bool OpenALSoundStream::Init(const BYTE *data, unsigned int datalen)
 
 
 Decoder::Decoder(const void* data, unsigned int datalen)
-  : Sample(NULL), NeedSwab(false)
+  : Sample(NULL), NeedSwab(false), NeedS8Conv(false), NeedS16Conv(false)
 {
     Sample = Sound_NewSample(SDL_RWFromConstMem(data, datalen), NULL, NULL, 65536);
 }
@@ -441,7 +474,15 @@ Decoder::~Decoder()
 bool Decoder::GetFormat(ALenum *format, ALuint *rate)
 {
     ALenum fmt = AL_NONE;
-    if(Sample->actual.format == AUDIO_U8)
+    if(Sample->actual.format == AUDIO_S8)
+    {
+        NeedS8Conv = true;
+        if(Sample->actual.channels == 1)
+            fmt = AL_FORMAT_MONO8;
+        else if(Sample->actual.channels == 2)
+            fmt = AL_FORMAT_STEREO8;
+    }
+    else if(Sample->actual.format == AUDIO_U8)
     {
         if(Sample->actual.channels == 1)
             fmt = AL_FORMAT_MONO8;
@@ -456,6 +497,15 @@ bool Decoder::GetFormat(ALenum *format, ALuint *rate)
         else if(Sample->actual.channels == 2)
             fmt = AL_FORMAT_STEREO16;
     }
+    else if(Sample->actual.format == AUDIO_U16LSB || Sample->actual.format == AUDIO_U16MSB)
+    {
+        NeedS16Conv = true;
+        NeedSwab = (Sample->actual.format != AUDIO_U16SYS);
+        if(Sample->actual.channels == 1)
+            fmt = AL_FORMAT_MONO16;
+        else if(Sample->actual.channels == 2)
+            fmt = AL_FORMAT_STEREO16;
+    }
 
     if(fmt == AL_NONE)
     {
@@ -489,6 +539,20 @@ void* Decoder::GetData(ALsizei *size)
         }
     }
 
+    if(NeedS8Conv)
+    {
+        char *samples = reinterpret_cast<char*>(data);
+        for(size_t i = 0;i < got;i++)
+            samples[i] = samples[i]^0x80;
+    }
+    if(NeedS16Conv)
+    {
+        short *samples = reinterpret_cast<short*>(data);
+        size_t count = got >> 1;
+        for(size_t i = 0;i < count;i++)
+            samples[i] = samples[i]^0x8000;
+    }
+
     *size = got;
     return data;
 }
diff --git a/src/sound/oalsdlsound.h b/src/sound/oalsdlsound.h
index 847edfb32..597a82558 100644
--- a/src/sound/oalsdlsound.h
+++ b/src/sound/oalsdlsound.h
@@ -22,6 +22,8 @@ class OpenALSoundStream : public SoundStream
     ALenum Format;
 
     bool NeedSwab;
+    bool NeedS8Conv;
+    bool NeedS16Conv;
     void *GetData(size_t bytes);
 
     // General methods
@@ -54,6 +56,8 @@ class Decoder
 {
     Sound_Sample *Sample;
     bool NeedSwab;
+    bool NeedS8Conv;
+    bool NeedS16Conv;
 
 public:
     Decoder(const void *data, unsigned int datalen);