Move hrtf.cpp/h to core

1 files changed, 91 insertions, 0 deletions

diff --git a/core/hrtf.h b/core/hrtf.h
new file mode 100644
index 00000000..f2dfc832
--- /dev/null
+++ b/core/hrtf.h
@@ -0,0 +1,91 @@
+#ifndef CORE_HRTF_H
+#define CORE_HRTF_H
+
+#include <array>
+#include <cstddef>
+#include <memory>
+#include <string>
+
+#include "almalloc.h"
+#include "aloptional.h"
+#include "alspan.h"
+#include "atomic.h"
+#include "ambidefs.h"
+#include "bufferline.h"
+#include "filters/splitter.h"
+#include "mixer/hrtfdefs.h"
+#include "intrusive_ptr.h"
+#include "vector.h"
+
+
+struct HrtfStore {
+    RefCount mRef;
+
+    uint sampleRate;
+    uint irSize;
+
+    struct Field {
+        float distance;
+        ubyte evCount;
+    };
+    /* NOTE: Fields are stored *backwards*. field[0] is the farthest field, and
+     * field[fdCount-1] is the nearest.
+     */
+    uint fdCount;
+    const Field *field;
+
+    struct Elevation {
+        ushort azCount;
+        ushort irOffset;
+    };
+    Elevation *elev;
+    const HrirArray *coeffs;
+    const ubyte2 *delays;
+
+    void add_ref();
+    void release();
+
+    DEF_PLACE_NEWDEL()
+};
+using HrtfStorePtr = al::intrusive_ptr<HrtfStore>;
+
+
+struct EvRadians { float value; };
+struct AzRadians { float value; };
+struct AngularPoint {
+    EvRadians Elev;
+    AzRadians Azim;
+};
+
+
+struct DirectHrtfState {
+    std::array<float,HrtfDirectDelay+BufferLineSize> mTemp;
+
+    /* HRTF filter state for dry buffer content */
+    uint mIrSize{0};
+    al::FlexArray<HrtfChannelState> mChannels;
+
+    DirectHrtfState(size_t numchans) : mChannels{numchans} { }
+    /**
+     * Produces HRTF filter coefficients for decoding B-Format, given a set of
+     * virtual speaker positions, a matching decoding matrix, and per-order
+     * high-frequency gains for the decoder. The calculated impulse responses
+     * are ordered and scaled according to the matrix input.
+     */
+    void build(const HrtfStore *Hrtf, const uint irSize,
+        const al::span<const AngularPoint> AmbiPoints, const float (*AmbiMatrix)[MaxAmbiChannels],
+        const float XOverFreq, const al::span<const float,MaxAmbiOrder+1> AmbiOrderHFGain);
+
+    static std::unique_ptr<DirectHrtfState> Create(size_t num_chans);
+
+    DEF_FAM_NEWDEL(DirectHrtfState, mChannels)
+};
+
+
+al::vector<std::string> EnumerateHrtf(al::optional<std::string> pathopt);
+HrtfStorePtr GetLoadedHrtf(const std::string &name, const uint devrate);
+
+void GetHrtfCoeffs(const HrtfStore *Hrtf, float elevation, float azimuth, float distance,
+    float spread, HrirArray &coeffs, const al::span<uint,2> delays);
+
+#endif /* CORE_HRTF_H */