From 86ae0460c957a90cdbb1be7a49c026da570c11f9 Mon Sep 17 00:00:00 2001
From: Max Maisel <max.maisel@posteo.de>
Date: Mon, 6 Aug 2018 17:04:26 +0200
Subject: [PATCH] More Biquad refactoring.

---
 src/effects/Biquad.cpp      | 45 +++++++++++++++++--------------------
 src/effects/Biquad.h        | 12 +++++-----
 src/effects/ScienFilter.cpp |  4 +---
 3 files changed, 27 insertions(+), 34 deletions(-)

diff --git a/src/effects/Biquad.cpp b/src/effects/Biquad.cpp
index ff1961d72..15cdedb66 100644
--- a/src/effects/Biquad.cpp
+++ b/src/effects/Biquad.cpp
@@ -18,8 +18,6 @@ Max Maisel
 
 Biquad::Biquad()
 {
-   pfIn = 0;
-   pfOut = 0;
    fNumerCoeffs[B0] = 1;
    fNumerCoeffs[B1] = 0;
    fNumerCoeffs[B2] = 0;
@@ -36,7 +34,7 @@ void Biquad::Reset()
    fPrevPrevOut = 0;
 }
 
-void Biquad::Process(int iNumSamples)
+void Biquad::Process(float* pfIn, float* pfOut, int iNumSamples)
 {
    for (int i = 0; i < iNumSamples; i++)
       *pfOut++ = ProcessOne(*pfIn++);
@@ -306,6 +304,26 @@ ArrayOf<Biquad> Biquad::CalcChebyshevType2Filter(int order, double fn, double fc
    return std::move(pBiquad);
 }
 
+void Biquad::ComplexDiv (float fNumerR, float fNumerI, float fDenomR, float fDenomI, float* pfQuotientR, float* pfQuotientI)
+{
+   float fDenom = square(fDenomR) + square(fDenomI);
+   *pfQuotientR = (fNumerR * fDenomR + fNumerI * fDenomI) / fDenom;
+   *pfQuotientI = (fNumerI * fDenomR - fNumerR * fDenomI) / fDenom;
+}
+
+bool Biquad::BilinTransform (float fSX, float fSY, float* pfZX, float* pfZY)
+{
+   float fDenom = square (1 - fSX) + square (fSY);
+   *pfZX = (1 - square (fSX) - square (fSY)) / fDenom;
+   *pfZY = 2 * fSY / fDenom;
+   return true;
+}
+
+float Biquad::Calc2D_DistSqr (float fX1, float fY1, float fX2, float fY2)
+{
+   return square (fX1 - fX2) + square (fY1 - fY2);
+}
+
 double Biquad::ChebyPoly(int Order, double NormFreq)   // NormFreq = 1 at the f0 point (where response is R dB down)
 {
    // Calc cosh (Order * acosh (NormFreq));
@@ -319,24 +337,3 @@ double Biquad::ChebyPoly(int Order, double NormFreq)   // NormFreq = 1 at the f0
    }
    return fSum;
 }
-
-void ComplexDiv (float fNumerR, float fNumerI, float fDenomR, float fDenomI, float* pfQuotientR, float* pfQuotientI)
-{
-   float fDenom = square(fDenomR) + square(fDenomI);
-   *pfQuotientR = (fNumerR * fDenomR + fNumerI * fDenomI) / fDenom;
-   *pfQuotientI = (fNumerI * fDenomR - fNumerR * fDenomI) / fDenom;
-}
-
-bool BilinTransform (float fSX, float fSY, float* pfZX, float* pfZY)
-{
-   float fDenom = square (1 - fSX) + square (fSY);
-   *pfZX = (1 - square (fSX) - square (fSY)) / fDenom;
-   *pfZY = 2 * fSY / fDenom;
-   return true;
-}
-
-float Calc2D_DistSqr (float fX1, float fY1, float fX2, float fY2)
-{
-   return square (fX1 - fX2) + square (fY1 - fY2);
-}
-
diff --git a/src/effects/Biquad.h b/src/effects/Biquad.h
index 321660c56..2261399bd 100644
--- a/src/effects/Biquad.h
+++ b/src/effects/Biquad.h
@@ -19,7 +19,7 @@ struct Biquad
 {
    Biquad();
    void Reset();
-   void Process(int iNumSamples);
+   void Process(float* pfIn, float* pfOut, int iNumSamples);
 
    enum
    {
@@ -47,8 +47,6 @@ struct Biquad
       return fOut;
    }
 
-   float* pfIn;
-   float* pfOut;
    float fNumerCoeffs[3]; // B0 B1 B2
    float fDenomCoeffs[2]; // A1 A2, A0 == 1.0
    float fPrevIn;
@@ -67,12 +65,12 @@ struct Biquad
    static ArrayOf<Biquad> CalcChebyshevType1Filter(int order, double fn, double fc, double ripple, int type);
    static ArrayOf<Biquad> CalcChebyshevType2Filter(int order, double fn, double fc, double ripple, int type);
 
+   static void ComplexDiv (float fNumerR, float fNumerI, float fDenomR, float fDenomI, float* pfQuotientR, float* pfQuotientI);
+   static bool BilinTransform (float fSX, float fSY, float* pfZX, float* pfZY);
+   static float Calc2D_DistSqr (float fX1, float fY1, float fX2, float fY2);
+
    static const double s_fChebyCoeffs[MAX_Order][MAX_Order + 1];
    static double ChebyPoly(int Order, double NormFreq);
 };
 
-void ComplexDiv (float fNumerR, float fNumerI, float fDenomR, float fDenomI, float* pfQuotientR, float* pfQuotientI);
-bool BilinTransform (float fSX, float fSY, float* pfZX, float* pfZY);
-float Calc2D_DistSqr (float fX1, float fY1, float fX2, float fY2);
-
 #endif
diff --git a/src/effects/ScienFilter.cpp b/src/effects/ScienFilter.cpp
index a451906f7..137c8460e 100644
--- a/src/effects/ScienFilter.cpp
+++ b/src/effects/ScienFilter.cpp
@@ -218,9 +218,7 @@ size_t EffectScienFilter::ProcessBlock(float **inBlock, float **outBlock, size_t
    float *ibuf = inBlock[0];
    for (int iPair = 0; iPair < (mOrder + 1) / 2; iPair++)
    {
-      mpBiquad[iPair].pfIn = ibuf;
-      mpBiquad[iPair].pfOut = outBlock[0];
-      mpBiquad[iPair].Process(blockLen);
+      mpBiquad[iPair].Process(ibuf, outBlock[0], blockLen);
       ibuf = outBlock[0];
    }