audio subsystem replacement: openal audio renderer and buffer class, removed deprecated files

audio.cpp

@@ -0,0 +1,181 @@
+/*
+This Source Code Form is subject to the
+terms of the Mozilla Public License, v.
+2.0. If a copy of the MPL was not
+distributed with this file, You can
+obtain one at
+http://mozilla.org/MPL/2.0/.
+*/
+
+#include "stdafx.h"
+
+#include "audio.h"
+#include "globals.h"
+#include "mczapkie/mctools.h"
+
+#define DR_WAV_IMPLEMENTATION
+#include "dr_wav.h"
+#define DR_FLAC_IMPLEMENTATION
+#include "dr_flac.h"
+
+namespace audio {
+
+openal_buffer::openal_buffer( std::string const &Filename ) :
+    name( Filename ) {
+
+    ::alGenBuffers( 1, &id );
+    // fetch audio data
+    if( Filename.substr( Filename.rfind( '.' ) ) == ".wav" ) {
+        // .wav file
+        auto *file { drwav_open_file( Filename.c_str() ) };
+        rate = file->sampleRate;
+        auto const samplecount { static_cast<std::size_t>( file->totalSampleCount ) };
+        data.resize( samplecount );
+        drwav_read_s16(
+            file,
+            samplecount,
+            &data[ 0 ] );
+        if( file->channels > 1 ) {
+            narrow_to_mono( file->channels );
+            data.resize( samplecount / file->channels );
+        }
+        // we're done with the disk data
+        drwav_close( file );
+    }
+    else {
+        // .flac or .ogg file
+        auto *file { drflac_open_file( Filename.c_str() ) };
+        rate = file->sampleRate;
+        auto const samplecount{ static_cast<std::size_t>( file->totalSampleCount ) };
+        data.resize( samplecount );
+        drflac_read_s16(
+            file,
+            samplecount,
+            &data[ 0 ] );
+        if( file->channels > 1 ) {
+            narrow_to_mono( file->channels );
+            data.resize( samplecount / file->channels );
+        }
+        // we're done with the disk data
+        drflac_close( file );
+    }
+    // send the data to openal side
+    ::alBufferData( id, AL_FORMAT_MONO16, data.data(), data.size() * sizeof( std::int16_t ), rate );
+    // and get rid of the source, we shouldn't need it anymore
+    // TBD, TODO: delay data fetching and transfers until the buffer is actually used?
+    std::vector<std::int16_t>().swap( data );
+}
+
+// mix specified number of interleaved multi-channel data, down to mono
+void
+openal_buffer::narrow_to_mono( std::uint16_t const Channelcount ) {
+ 
+    std::size_t monodataindex { 0 };
+    std::int32_t accumulator { 0 };
+    auto channelcount { Channelcount };
+
+    for( auto const channeldata : data ) {
+
+        accumulator += channeldata;
+        if( --channelcount == 0 ) {
+
+            data[ monodataindex++ ] = accumulator / Channelcount;
+            accumulator = 0;
+            channelcount = Channelcount;
+        }
+    }
+}
+
+
+
+buffer_manager::~buffer_manager() {
+
+    for( auto &buffer : m_buffers ) {
+        if( buffer.id != null_resource ) {
+            ::alDeleteBuffers( 1, &( buffer.id ) );
+        }
+    }
+}
+
+// creates buffer object out of data stored in specified file. returns: handle to the buffer or null_handle if creation failed
+buffer_handle
+buffer_manager::create( std::string const &Filename ) {
+
+    auto filename { ToLower( Filename ) };
+
+    auto const dotpos { filename.rfind( '.' ) };
+    if( ( dotpos != std::string::npos )
+     && ( dotpos != filename.rfind( ".." ) + 1 ) ) {
+        // trim extension if there's one, but don't mistake folder traverse for extension
+        filename.erase( dotpos );
+    }
+    // convert slashes
+    std::replace(
+        std::begin( filename ), std::end( filename ),
+        '\\', '/' );
+
+    // try dynamic-specific sounds first
+    auto lookup { find_buffer( Global::asCurrentDynamicPath + filename ) };
+    if( lookup != null_handle ) {
+        return lookup;
+    }
+    std::string filelookup { find_file( Global::asCurrentDynamicPath + filename ) };
+    if( false == filelookup.empty() ) {
+        return emplace( filelookup );
+    }
+    // if dynamic-specific lookup finds nothing, try the default sound folder
+    lookup = find_buffer( szSoundPath + filename );
+    if( lookup != null_handle ) {
+        return lookup;
+    }
+    filelookup = find_file( szSoundPath + filename );
+    if( false == filelookup.empty() ) {
+        return emplace( filelookup );
+    }
+    // if we still didn't find anything, give up
+    return null_handle;
+}
+
+// places in the bank a buffer containing data stored in specified file. returns: handle to the buffer
+buffer_handle
+buffer_manager::emplace( std::string Filename ) {
+
+    buffer_handle const handle { m_buffers.size() };
+    m_buffers.emplace_back( Filename );
+
+    // NOTE: we store mapping without file type extension, to simplify lookups
+    m_buffermappings.emplace(
+        Filename.erase( Filename.rfind( '.' ) ),
+        handle );
+
+    return handle;
+}
+
+buffer_handle
+buffer_manager::find_buffer( std::string const &Buffername ) const {
+
+    auto lookup = m_buffermappings.find( Buffername );
+    if( lookup != m_buffermappings.end() )
+        return lookup->second;
+    else
+        return null_handle;
+}
+
+
+std::string
+buffer_manager::find_file( std::string const &Filename ) const {
+
+    std::vector<std::string> const extensions { ".wav", ".flac", ".ogg" };
+
+    for( auto const &extension : extensions ) {
+        if( FileExists( Filename + extension ) ) {
+            // valid name on success
+            return Filename + extension;
+        }
+    }
+    return {}; // empty string on failure
+}
+
+} // audio
+
+//---------------------------------------------------------------------------