Initial audio interface classes

include/boo/audiodev/AudioMatrix.hpp

@@ -0,0 +1,56 @@
+#ifndef BOO_AUDIOMATRIX_HPP
+#define BOO_AUDIOMATRIX_HPP
+
+#include "IAudioVoice.hpp"
+#include <vector>
+#include <stdint.h>
+
+namespace boo
+{
+
+class AudioMatrixMono
+{
+    AudioChannelSet m_setOut;
+    float m_coefs[8];
+    std::vector<int16_t> m_interleaveBuf;
+public:
+    AudioMatrixMono(AudioChannelSet setOut)
+    : m_setOut(setOut) {setDefaultMatrixCoefficients();}
+
+    AudioChannelSet setOut() const {return m_setOut;}
+    void setDefaultMatrixCoefficients();
+    void setMatrixCoefficients(const float coefs[8])
+    {
+        for (int i=0 ; i<8 ; ++i)
+            m_coefs[i] = coefs[i];
+    }
+
+    void bufferMonoSampleData(IAudioVoice& voice, const int16_t* data, size_t samples);
+};
+
+class AudioMatrixStereo
+{
+    AudioChannelSet m_setOut;
+    float m_coefs[8][2];
+    std::vector<int16_t> m_interleaveBuf;
+public:
+    AudioMatrixStereo(AudioChannelSet setOut)
+    : m_setOut(setOut) {setDefaultMatrixCoefficients();}
+
+    AudioChannelSet setOut() const {return m_setOut;}
+    void setDefaultMatrixCoefficients();
+    void setMatrixCoefficients(const float coefs[8][2])
+    {
+        for (int i=0 ; i<8 ; ++i)
+        {
+            m_coefs[i][0] = coefs[i][0];
+            m_coefs[i][1] = coefs[i][1];
+        }
+    }
+
+    void bufferStereoSampleData(IAudioVoice& voice, const int16_t* data, size_t frames);
+};
+
+}
+
+#endif // BOO_AUDIOMATRIX_HPP

include/boo/audiodev/IAudioVoice.hpp

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+#ifndef BOO_IAUDIOVOICE_HPP
+#define BOO_IAUDIOVOICE_HPP
+
+#include <stddef.h>
+#include <stdint.h>
+
+namespace boo
+{
+
+enum class AudioChannelSet
+{
+    Stereo,
+    Quad,
+    Surround51,
+    Surround71
+};
+
+enum class AudioChannel
+{
+    FrontLeft,
+    FrontRight,
+    RearLeft,
+    RearRight,
+    FrontCenter,
+    LFE,
+    SideLeft,
+    SideRight
+};
+
+struct ChannelMap
+{
+    unsigned m_channelCount = 0;
+    AudioChannel m_channels[8] = {};
+};
+
+static inline unsigned ChannelCount(AudioChannelSet layout)
+{
+    switch (layout)
+    {
+    case AudioChannelSet::Stereo:
+        return 2;
+    case AudioChannelSet::Quad:
+        return 4;
+    case AudioChannelSet::Surround51:
+        return 6;
+    case AudioChannelSet::Surround71:
+        return 8;
+    }
+    return 0;
+}
+
+struct IAudioVoice
+{
+    /** Get voice's actual channel-map based on client request and HW capabilities */
+    virtual const ChannelMap& channelMap() const=0;
+
+    /** Called by client in response to IAudioVoiceCallback::needsNextBuffer()
+     *  Supplying channel-interleaved sample data */
+    virtual void bufferSampleData(const int16_t* data, size_t frames)=0;
+};
+
+}
+
+#endif // BOO_IAUDIOVOICE_HPP

include/boo/audiodev/IAudioVoiceAllocator.hpp

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+#ifndef BOO_IAUDIOVOICEALLOCATOR_HPP
+#define BOO_IAUDIOVOICEALLOCATOR_HPP
+
+#include "IAudioVoice.hpp"
+#include <memory>
+
+namespace boo
+{
+
+struct IAudioVoiceCallback
+{
+    /** Boo calls this on behalf of the audio platform to request more audio
+     *  frames from the client */
+    virtual void needsNextBuffer(IAudioVoice* voice, size_t frames)=0;
+};
+
+struct IAudioVoiceAllocator
+{
+    /** Client calls this to request allocation of new mixer-voice.
+     *  Returns empty unique_ptr if necessary resources aren't available.
+     *  ChannelLayout automatically reduces to maximum-supported layout by HW. */
+    virtual std::unique_ptr<IAudioVoice> allocateNewVoice(AudioChannelSet layoutOut,
+                                                          unsigned sampleRate,
+                                                          IAudioVoiceCallback* cb)=0;
+};
+
+}
+
+#endif // BOO_IAUDIOVOICEALLOCATOR_HPP