1 files changed, 0 insertions, 113 deletions
diff --git a/Alc/filters/biquad.h b/Alc/filters/biquad.h
deleted file mode 100644
index 893a69a9..00000000
--- a/Alc/filters/biquad.h
+++ /dev/null
@@ -1,113 +0,0 @@
-#ifndef FILTERS_BIQUAD_H
-#define FILTERS_BIQUAD_H
-
-#include <cmath>
-#include <utility>
-
-#include "math_defs.h"
-
-
-/* Filters implementation is based on the "Cookbook formulae for audio
- * EQ biquad filter coefficients" by Robert Bristow-Johnson
- * http://www.musicdsp.org/files/Audio-EQ-Cookbook.txt
- */
-/* Implementation note: For the shelf filters, the specified gain is for the
- * reference frequency, which is the centerpoint of the transition band. This
- * better matches EFX filter design. To set the gain for the shelf itself, use
- * the square root of the desired linear gain (or halve the dB gain).
- */
-
-enum class BiquadType {
-    /** EFX-style low-pass filter, specifying a gain and reference frequency. */
-    HighShelf,
-    /** EFX-style high-pass filter, specifying a gain and reference frequency. */
-    LowShelf,
-    /** Peaking filter, specifying a gain and reference frequency. */
-    Peaking,
-
-    /** Low-pass cut-off filter, specifying a cut-off frequency. */
-    LowPass,
-    /** High-pass cut-off filter, specifying a cut-off frequency. */
-    HighPass,
-    /** Band-pass filter, specifying a center frequency. */
-    BandPass,
-};
-
-template<typename Real>
-class BiquadFilterR {
-    /* Last two delayed components for direct form II. */
-    Real z1{0.0f}, z2{0.0f};
-    /* Transfer function coefficients "b" (numerator) */
-    Real b0{1.0f}, b1{0.0f}, b2{0.0f};
-    /* Transfer function coefficients "a" (denominator; a0 is pre-applied). */
-    Real a1{0.0f}, a2{0.0f};
-
-public:
-    void clear() noexcept { z1 = z2 = 0.0f; }
-
-    /**
-     * Sets the filter state for the specified filter type and its parameters.
-     *
-     * \param type The type of filter to apply.
-     * \param gain The gain for the reference frequency response. Only used by
-     *             the Shelf and Peaking filter types.
-     * \param f0norm The reference frequency normal (ref_freq / sample_rate).
-     *               This is the center point for the Shelf, Peaking, and
-     *               BandPass filter types, or the cutoff frequency for the
-     *               LowPass and HighPass filter types.
-     * \param rcpQ The reciprocal of the Q coefficient for the filter's
-     *             transition band. Can be generated from rcpQFromSlope or
-     *             rcpQFromBandwidth as needed.
-     */
-    void setParams(BiquadType type, Real gain, Real f0norm, Real rcpQ);
-
-    void copyParamsFrom(const BiquadFilterR &other)
-    {
-        b0 = other.b0;
-        b1 = other.b1;
-        b2 = other.b2;
-        a1 = other.a1;
-        a2 = other.a2;
-    }
-
-
-    void process(Real *dst, const Real *src, int numsamples);
-
-    /* Rather hacky. It's just here to support "manual" processing. */
-    std::pair<Real,Real> getComponents() const noexcept
-    { return {z1, z2}; }
-    void setComponents(Real z1_, Real z2_) noexcept
-    { z1 = z1_; z2 = z2_; }
-    Real processOne(const Real in, Real &z1_, Real &z2_) const noexcept
-    {
-        Real out{in*b0 + z1_};
-        z1_ = in*b1 - out*a1 + z2_;
-        z2_ = in*b2 - out*a2;
-        return out;
-    }
-
-    /**
-     * Calculates the rcpQ (i.e. 1/Q) coefficient for shelving filters, using
-     * the reference gain and shelf slope parameter.
-     * \param gain 0 < gain
-     * \param slope 0 < slope <= 1
-     */
-    static Real rcpQFromSlope(Real gain, Real slope)
-    { return std::sqrt((gain + 1.0f/gain)*(1.0f/slope - 1.0f) + 2.0f); }
-
-    /**
-     * Calculates the rcpQ (i.e. 1/Q) coefficient for filters, using the
-     * normalized reference frequency and bandwidth.
-     * \param f0norm 0 < f0norm < 0.5.
-     * \param bandwidth 0 < bandwidth
-     */
-    static Real rcpQFromBandwidth(Real f0norm, Real bandwidth)
-    {
-        const Real w0{al::MathDefs<Real>::Tau() * f0norm};
-        return 2.0f*std::sinh(std::log(Real{2.0f})/2.0f*bandwidth*w0/std::sin(w0));
-    }
-};
-
-using BiquadFilter = BiquadFilterR<float>;
-
-#endif /* FILTERS_BIQUAD_H */