Support quad, 5.1, and 7.1 with OpenAL and ffmpeg

The other decoders don't guarantee any channel ordering, which makes them
useless.

apps/openmw/mwrender/videoplayer.cpp

@@ -333,6 +333,12 @@ public:
             *chans = MWSound::ChannelConfig_Mono;
         else if(is->audio_st->codec->channel_layout == AV_CH_LAYOUT_STEREO)
             *chans = MWSound::ChannelConfig_Stereo;
+        else if(is->audio_st->codec->channel_layout == AV_CH_LAYOUT_QUAD)
+            *chans = MWSound::ChannelConfig_Quad;
+        else if(is->audio_st->codec->channel_layout == AV_CH_LAYOUT_5POINT1)
+            *chans = MWSound::ChannelConfig_5point1;
+        else if(is->audio_st->codec->channel_layout == AV_CH_LAYOUT_7POINT1)
+            *chans = MWSound::ChannelConfig_7point1;
         else if(is->audio_st->codec->channel_layout == 0)
         {
             /* Unknown channel layout. Try to guess. */

apps/openmw/mwsound/ffmpeg_decoder.cpp

@@ -347,6 +347,12 @@ void FFmpeg_Decoder::getInfo(int *samplerate, ChannelConfig *chans, SampleType *
         *chans = ChannelConfig_Mono;
     else if(stream->mCodecCtx->channel_layout == AV_CH_LAYOUT_STEREO)
         *chans = ChannelConfig_Stereo;
+    else if(stream->mCodecCtx->channel_layout == AV_CH_LAYOUT_QUAD)
+        *chans = ChannelConfig_Quad;
+    else if(stream->mCodecCtx->channel_layout == AV_CH_LAYOUT_5POINT1)
+        *chans = ChannelConfig_5point1;
+    else if(stream->mCodecCtx->channel_layout == AV_CH_LAYOUT_7POINT1)
+        *chans = ChannelConfig_7point1;
     else if(stream->mCodecCtx->channel_layout == 0)
     {
         /* Unknown channel layout. Try to guess. */

apps/openmw/mwsound/openal_output.cpp

@@ -61,6 +61,34 @@ static ALenum getALFormat(ChannelConfig chans, SampleType type)
         if(fmtlist[i].chans == chans && fmtlist[i].type == type)
             return fmtlist[i].format;
     }
+
+    if(alIsExtensionPresent("AL_EXT_MCFORMATS"))
+    {
+        static const struct {
+            char name[32];
+            ChannelConfig chans;
+            SampleType type;
+        } mcfmtlist[] = {
+            { "AL_FORMAT_QUAD16",   ChannelConfig_Quad,    SampleType_Int16 },
+            { "AL_FORMAT_QUAD8",    ChannelConfig_Quad,    SampleType_UInt8 },
+            { "AL_FORMAT_51CHN16",  ChannelConfig_5point1, SampleType_Int16 },
+            { "AL_FORMAT_51CHN8",   ChannelConfig_5point1, SampleType_UInt8 },
+            { "AL_FORMAT_71CHN16",  ChannelConfig_7point1, SampleType_Int16 },
+            { "AL_FORMAT_71CHN8",   ChannelConfig_7point1, SampleType_UInt8 },
+        };
+        static const size_t mcfmtlistsize = sizeof(mcfmtlist)/sizeof(mcfmtlist[0]);
+
+        for(size_t i = 0;i < mcfmtlistsize;i++)
+        {
+            if(mcfmtlist[i].chans == chans && mcfmtlist[i].type == type)
+            {
+                ALenum format = alGetEnumValue(mcfmtlist[i].name);
+                if(format != 0 && format != -1)
+                    return format;
+            }
+        }
+    }
+
     fail(std::string("Unsupported sound format (")+getChannelConfigName(chans)+", "+getSampleTypeName(type)+")");
     return AL_NONE;
 }

apps/openmw/mwsound/sound_decoder.hpp

@@ -15,7 +15,10 @@ namespace MWSound
 
     enum ChannelConfig {
         ChannelConfig_Mono,
-        ChannelConfig_Stereo
+        ChannelConfig_Stereo,
+        ChannelConfig_Quad,
+        ChannelConfig_5point1,
+        ChannelConfig_7point1
     };
     const char *getChannelConfigName(ChannelConfig config);
 

apps/openmw/mwsound/soundmanagerimp.cpp

@@ -622,8 +622,11 @@ namespace MWSound
     {
         switch(config)
         {
-            case ChannelConfig_Mono:   return "Mono";
-            case ChannelConfig_Stereo: return "Stereo";
+            case ChannelConfig_Mono:    return "Mono";
+            case ChannelConfig_Stereo:  return "Stereo";
+            case ChannelConfig_Quad:    return "Quad";
+            case ChannelConfig_5point1: return "5.1 Surround";
+            case ChannelConfig_7point1: return "7.1 Surround";
         }
         return "(unknown channel config)";
     }
@@ -632,8 +635,11 @@ namespace MWSound
     {
         switch(config)
         {
-            case ChannelConfig_Mono:   frames *= 1; break;
-            case ChannelConfig_Stereo: frames *= 2; break;
+            case ChannelConfig_Mono:    frames *= 1; break;
+            case ChannelConfig_Stereo:  frames *= 2; break;
+            case ChannelConfig_Quad:    frames *= 4; break;
+            case ChannelConfig_5point1: frames *= 6; break;
+            case ChannelConfig_7point1: frames *= 8; break;
         }
         switch(type)
         {