/*

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 *     from this software without specific prior written permission.

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 * THIS SOFTWARE IS PROVIDED BY APPLE AND ITS CONTRIBUTORS "AS IS" AND ANY

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#include "HRTFDatabase.h"

#include "HRTFElevation.h"

using namespace std;

namespace WebCore {

const int HRTFDatabase::MinElevation = -45;

const int HRTFDatabase::MaxElevation = 90;

const unsigned HRTFDatabase::RawElevationAngleSpacing = 15;

const unsigned HRTFDatabase::NumberOfRawElevations = 10; // -45 -> +90 (each 15 degrees)

const unsigned HRTFDatabase::InterpolationFactor = 1;

const unsigned HRTFDatabase::NumberOfTotalElevations = NumberOfRawElevations * InterpolationFactor;

nsReturnRef<HRTFDatabase> HRTFDatabase::create(float sampleRate)

{

    return nsReturnRef<HRTFDatabase>(new HRTFDatabase(sampleRate));

}

HRTFDatabase::HRTFDatabase(float sampleRate)

    : m_sampleRate(sampleRate)

{

    m_elevations.SetLength(NumberOfTotalElevations);

    unsigned elevationIndex = 0;

    for (int elevation = MinElevation; elevation <= MaxElevation; elevation += RawElevationAngleSpacing) {

        nsAutoRef<HRTFElevation> hrtfElevation(HRTFElevation::createBuiltin(elevation, sampleRate));

        MOZ_ASSERT(hrtfElevation.get());

        if (!hrtfElevation.get())

            return;

        m_elevations[elevationIndex] = hrtfElevation.out();

        elevationIndex += InterpolationFactor;

    }

    // Now, go back and interpolate elevations.

    if (InterpolationFactor > 1) {

        for (unsigned i = 0; i < NumberOfTotalElevations; i += InterpolationFactor) {

            unsigned j = (i + InterpolationFactor);

            if (j >= NumberOfTotalElevations)

                j = i; // for last elevation interpolate with itself

            // Create the interpolated convolution kernels and delays.

            for (unsigned jj = 1; jj < InterpolationFactor; ++jj) {

                float x = static_cast<float>(jj) / static_cast<float>(InterpolationFactor);

                m_elevations[i + jj] = HRTFElevation::createByInterpolatingSlices(m_elevations[i].get(), m_elevations[j].get(), x, sampleRate);

                MOZ_ASSERT(m_elevations[i + jj].get());

            }

        }

    }

}

size_t HRTFDatabase::sizeOfIncludingThis(mozilla::MallocSizeOf aMallocSizeOf) const

{

    size_t amount = aMallocSizeOf(this);

    amount += m_elevations.ShallowSizeOfExcludingThis(aMallocSizeOf);

    for (size_t i = 0; i < m_elevations.Length(); i++) {

      amount += m_elevations[i]->sizeOfIncludingThis(aMallocSizeOf);

    }

    return amount;

}

void HRTFDatabase::getKernelsFromAzimuthElevation(double azimuthBlend, unsigned azimuthIndex, double elevationAngle, HRTFKernel* &kernelL, HRTFKernel* &kernelR,

                                                  double& frameDelayL, double& frameDelayR)

{

    unsigned elevationIndex = indexFromElevationAngle(elevationAngle);

    MOZ_ASSERT(elevationIndex < m_elevations.Length() && m_elevations.Length() > 0);

    if (!m_elevations.Length()) {

        kernelL = 0;

        kernelR = 0;

        return;

    }

    if (elevationIndex > m_elevations.Length() - 1)

        elevationIndex = m_elevations.Length() - 1;

    HRTFElevation* hrtfElevation = m_elevations[elevationIndex].get();

    MOZ_ASSERT(hrtfElevation);

    if (!hrtfElevation) {

        kernelL = 0;

        kernelR = 0;

        return;

    }

    hrtfElevation->getKernelsFromAzimuth(azimuthBlend, azimuthIndex, kernelL, kernelR, frameDelayL, frameDelayR);

}

unsigned HRTFDatabase::indexFromElevationAngle(double elevationAngle)

{

    // Clamp to allowed range.

    elevationAngle = mozilla::clamped(elevationAngle,

                                      static_cast<double>(MinElevation),

                                      static_cast<double>(MaxElevation));

    unsigned elevationIndex = static_cast<int>(InterpolationFactor * (elevationAngle - MinElevation) / RawElevationAngleSpacing);

    return elevationIndex;

}

} // namespace WebCore