Use a dodecahedron for the ambisonic HRTF decode

Also uses full second-order for "basic" HRTF rendering. Note that the supplied
matrix is full third-order, but only the first- and second-order coefficients
are used. The base matrices are the identical, only differing by the high-
frequency scalars.

1 files changed, 51 insertions, 68 deletions

diff --git a/Alc/panning.cpp b/Alc/panning.cpp
index 783fe480..9c3be106 100644
--- a/Alc/panning.cpp
+++ b/Alc/panning.cpp
@@ -618,78 +618,62 @@ void InitHQPanning(ALCdevice *device, const AmbDecConf *conf, const ALsizei (&sp
 void InitHrtfPanning(ALCdevice *device)
 {
     /* NOTE: azimuth goes clockwise. */
-    static constexpr AngularPoint AmbiPoints[] = {
-        { DEG2RAD( 90.0f), DEG2RAD(   0.0f) },
-        { DEG2RAD( 35.2643897f), DEG2RAD(  45.0f) },
-        { DEG2RAD( 35.2643897f), DEG2RAD( 135.0f) },
-        { DEG2RAD( 35.2643897f), DEG2RAD(-135.0f) },
-        { DEG2RAD( 35.2643897f), DEG2RAD( -45.0f) },
-        { DEG2RAD(  0.0f), DEG2RAD(   0.0f) },
-        { DEG2RAD(  0.0f), DEG2RAD(  45.0f) },
-        { DEG2RAD(  0.0f), DEG2RAD(  90.0f) },
-        { DEG2RAD(  0.0f), DEG2RAD( 135.0f) },
-        { DEG2RAD(  0.0f), DEG2RAD( 180.0f) },
-        { DEG2RAD(  0.0f), DEG2RAD(-135.0f) },
-        { DEG2RAD(  0.0f), DEG2RAD( -90.0f) },
-        { DEG2RAD(  0.0f), DEG2RAD( -45.0f) },
-        { DEG2RAD(-35.2643897f), DEG2RAD(  45.0f) },
-        { DEG2RAD(-35.2643897f), DEG2RAD( 135.0f) },
-        { DEG2RAD(-35.2643897f), DEG2RAD(-135.0f) },
-        { DEG2RAD(-35.2643897f), DEG2RAD( -45.0f) },
-        { DEG2RAD(-90.0f), DEG2RAD(   0.0f) },
+    static constexpr AngularPoint AmbiPoints[]{
+        { DEG2RAD( 35.264390f), DEG2RAD( -45.000000f) },
+        { DEG2RAD( 35.264390f), DEG2RAD(  45.000000f) },
+        { DEG2RAD( 35.264390f), DEG2RAD( 135.000000f) },
+        { DEG2RAD( 35.264390f), DEG2RAD(-135.000000f) },
+        { DEG2RAD(-35.264390f), DEG2RAD( -45.000000f) },
+        { DEG2RAD(-35.264390f), DEG2RAD(  45.000000f) },
+        { DEG2RAD(-35.264390f), DEG2RAD( 135.000000f) },
+        { DEG2RAD(-35.264390f), DEG2RAD(-135.000000f) },
+        { DEG2RAD(  0.000000f), DEG2RAD( -20.905157f) },
+        { DEG2RAD(  0.000000f), DEG2RAD(  20.905157f) },
+        { DEG2RAD(  0.000000f), DEG2RAD( 159.094843f) },
+        { DEG2RAD(  0.000000f), DEG2RAD(-159.094843f) },
+        { DEG2RAD( 20.905157f), DEG2RAD( -90.000000f) },
+        { DEG2RAD(-20.905157f), DEG2RAD( -90.000000f) },
+        { DEG2RAD(-20.905157f), DEG2RAD(  90.000000f) },
+        { DEG2RAD( 20.905157f), DEG2RAD(  90.000000f) },
+        { DEG2RAD( 69.094843f), DEG2RAD(   0.000000f) },
+        { DEG2RAD(-69.094843f), DEG2RAD(   0.000000f) },
+        { DEG2RAD(-69.094843f), DEG2RAD( 180.000000f) },
+        { DEG2RAD( 69.094843f), DEG2RAD( 180.000000f) },
     };
-    static constexpr ALfloat AmbiMatrixFOA[][MAX_AMBI_COEFFS] = {
-        { 5.55555556e-02f,  0.00000000e+00f,  1.23717915e-01f,  0.00000000e+00f },
-        { 5.55555556e-02f, -5.00000000e-02f,  7.14285715e-02f,  5.00000000e-02f },
-        { 5.55555556e-02f, -5.00000000e-02f,  7.14285715e-02f, -5.00000000e-02f },
-        { 5.55555556e-02f,  5.00000000e-02f,  7.14285715e-02f, -5.00000000e-02f },
-        { 5.55555556e-02f,  5.00000000e-02f,  7.14285715e-02f,  5.00000000e-02f },
-        { 5.55555556e-02f,  0.00000000e+00f,  0.00000000e+00f,  8.66025404e-02f },
-        { 5.55555556e-02f, -6.12372435e-02f,  0.00000000e+00f,  6.12372435e-02f },
-        { 5.55555556e-02f, -8.66025404e-02f,  0.00000000e+00f,  0.00000000e+00f },
-        { 5.55555556e-02f, -6.12372435e-02f,  0.00000000e+00f, -6.12372435e-02f },
-        { 5.55555556e-02f,  0.00000000e+00f,  0.00000000e+00f, -8.66025404e-02f },
-        { 5.55555556e-02f,  6.12372435e-02f,  0.00000000e+00f, -6.12372435e-02f },
-        { 5.55555556e-02f,  8.66025404e-02f,  0.00000000e+00f,  0.00000000e+00f },
-        { 5.55555556e-02f,  6.12372435e-02f,  0.00000000e+00f,  6.12372435e-02f },
-        { 5.55555556e-02f, -5.00000000e-02f, -7.14285715e-02f,  5.00000000e-02f },
-        { 5.55555556e-02f, -5.00000000e-02f, -7.14285715e-02f, -5.00000000e-02f },
-        { 5.55555556e-02f,  5.00000000e-02f, -7.14285715e-02f, -5.00000000e-02f },
-        { 5.55555556e-02f,  5.00000000e-02f, -7.14285715e-02f,  5.00000000e-02f },
-        { 5.55555556e-02f,  0.00000000e+00f, -1.23717915e-01f,  0.00000000e+00f },
-    }, AmbiMatrixHOA[][MAX_AMBI_COEFFS] = {
-        { 5.55555556e-02f,  0.00000000e+00f,  1.23717915e-01f,  0.00000000e+00f,  0.00000000e+00f,  0.00000000e+00f },
-        { 5.55555556e-02f, -5.00000000e-02f,  7.14285715e-02f,  5.00000000e-02f, -4.55645099e-02f,  0.00000000e+00f },
-        { 5.55555556e-02f, -5.00000000e-02f,  7.14285715e-02f, -5.00000000e-02f,  4.55645099e-02f,  0.00000000e+00f },
-        { 5.55555556e-02f,  5.00000000e-02f,  7.14285715e-02f, -5.00000000e-02f, -4.55645099e-02f,  0.00000000e+00f },
-        { 5.55555556e-02f,  5.00000000e-02f,  7.14285715e-02f,  5.00000000e-02f,  4.55645099e-02f,  0.00000000e+00f },
-        { 5.55555556e-02f,  0.00000000e+00f,  0.00000000e+00f,  8.66025404e-02f,  0.00000000e+00f,  1.29099445e-01f },
-        { 5.55555556e-02f, -6.12372435e-02f,  0.00000000e+00f,  6.12372435e-02f, -6.83467648e-02f,  0.00000000e+00f },
-        { 5.55555556e-02f, -8.66025404e-02f,  0.00000000e+00f,  0.00000000e+00f,  0.00000000e+00f, -1.29099445e-01f },
-        { 5.55555556e-02f, -6.12372435e-02f,  0.00000000e+00f, -6.12372435e-02f,  6.83467648e-02f,  0.00000000e+00f },
-        { 5.55555556e-02f,  0.00000000e+00f,  0.00000000e+00f, -8.66025404e-02f,  0.00000000e+00f,  1.29099445e-01f },
-        { 5.55555556e-02f,  6.12372435e-02f,  0.00000000e+00f, -6.12372435e-02f, -6.83467648e-02f,  0.00000000e+00f },
-        { 5.55555556e-02f,  8.66025404e-02f,  0.00000000e+00f,  0.00000000e+00f,  0.00000000e+00f, -1.29099445e-01f },
-        { 5.55555556e-02f,  6.12372435e-02f,  0.00000000e+00f,  6.12372435e-02f,  6.83467648e-02f,  0.00000000e+00f },
-        { 5.55555556e-02f, -5.00000000e-02f, -7.14285715e-02f,  5.00000000e-02f, -4.55645099e-02f,  0.00000000e+00f },
-        { 5.55555556e-02f, -5.00000000e-02f, -7.14285715e-02f, -5.00000000e-02f,  4.55645099e-02f,  0.00000000e+00f },
-        { 5.55555556e-02f,  5.00000000e-02f, -7.14285715e-02f, -5.00000000e-02f, -4.55645099e-02f,  0.00000000e+00f },
-        { 5.55555556e-02f,  5.00000000e-02f, -7.14285715e-02f,  5.00000000e-02f,  4.55645099e-02f,  0.00000000e+00f },
-        { 5.55555556e-02f,  0.00000000e+00f, -1.23717915e-01f,  0.00000000e+00f,  0.00000000e+00f,  0.00000000e+00f },
+    static constexpr ALfloat AmbiMatrix[][MAX_AMBI_COEFFS]{
+        { 5.00000000e-02f,  5.00000000e-02f,  5.00000000e-02f,  5.00000000e-02f,  6.45497224e-02f,  6.45497224e-02f,  0.00000000e+00f,  6.45497224e-02f,  0.00000000e+00f,  1.48264644e-02f,  6.33865691e-02f,  1.01126676e-01f, -7.36485380e-02f, -1.09260065e-02f,  7.08683387e-02f, -1.01622099e-01f },
+        { 5.00000000e-02f, -5.00000000e-02f,  5.00000000e-02f,  5.00000000e-02f, -6.45497224e-02f, -6.45497224e-02f,  0.00000000e+00f,  6.45497224e-02f,  0.00000000e+00f, -1.48264644e-02f, -6.33865691e-02f, -1.01126676e-01f, -7.36485380e-02f, -1.09260065e-02f,  7.08683387e-02f, -1.01622099e-01f },
+        { 5.00000000e-02f, -5.00000000e-02f,  5.00000000e-02f, -5.00000000e-02f,  6.45497224e-02f, -6.45497224e-02f,  0.00000000e+00f, -6.45497224e-02f,  0.00000000e+00f, -1.48264644e-02f,  6.33865691e-02f, -1.01126676e-01f, -7.36485380e-02f,  1.09260065e-02f,  7.08683387e-02f,  1.01622099e-01f },
+        { 5.00000000e-02f,  5.00000000e-02f,  5.00000000e-02f, -5.00000000e-02f, -6.45497224e-02f,  6.45497224e-02f,  0.00000000e+00f, -6.45497224e-02f,  0.00000000e+00f,  1.48264644e-02f, -6.33865691e-02f,  1.01126676e-01f, -7.36485380e-02f,  1.09260065e-02f,  7.08683387e-02f,  1.01622099e-01f },
+        { 5.00000000e-02f,  5.00000000e-02f, -5.00000000e-02f,  5.00000000e-02f,  6.45497224e-02f, -6.45497224e-02f,  0.00000000e+00f, -6.45497224e-02f,  0.00000000e+00f,  1.48264644e-02f, -6.33865691e-02f,  1.01126676e-01f,  7.36485380e-02f, -1.09260065e-02f, -7.08683387e-02f, -1.01622099e-01f },
+        { 5.00000000e-02f, -5.00000000e-02f, -5.00000000e-02f,  5.00000000e-02f, -6.45497224e-02f,  6.45497224e-02f,  0.00000000e+00f, -6.45497224e-02f,  0.00000000e+00f, -1.48264644e-02f,  6.33865691e-02f, -1.01126676e-01f,  7.36485380e-02f, -1.09260065e-02f, -7.08683387e-02f, -1.01622099e-01f },
+        { 5.00000000e-02f, -5.00000000e-02f, -5.00000000e-02f, -5.00000000e-02f,  6.45497224e-02f,  6.45497224e-02f,  0.00000000e+00f,  6.45497224e-02f,  0.00000000e+00f, -1.48264644e-02f, -6.33865691e-02f, -1.01126676e-01f,  7.36485380e-02f,  1.09260065e-02f, -7.08683387e-02f,  1.01622099e-01f },
+        { 5.00000000e-02f,  5.00000000e-02f, -5.00000000e-02f, -5.00000000e-02f, -6.45497224e-02f, -6.45497224e-02f,  0.00000000e+00f,  6.45497224e-02f,  0.00000000e+00f,  1.48264644e-02f,  6.33865691e-02f,  1.01126676e-01f,  7.36485380e-02f,  1.09260065e-02f, -7.08683387e-02f,  1.01622099e-01f },
+        { 5.00000000e-02f,  3.09016994e-02f,  0.00000000e+00f,  8.09016994e-02f,  6.45497224e-02f,  0.00000000e+00f, -5.59016994e-02f,  0.00000000e+00f,  7.21687836e-02f,  7.76323754e-02f,  0.00000000e+00f, -1.49775925e-01f,  0.00000000e+00f, -2.95083663e-02f,  0.00000000e+00f,  7.76323754e-02f },
+        { 5.00000000e-02f, -3.09016994e-02f,  0.00000000e+00f,  8.09016994e-02f, -6.45497224e-02f,  0.00000000e+00f, -5.59016994e-02f,  0.00000000e+00f,  7.21687836e-02f, -7.76323754e-02f,  0.00000000e+00f,  1.49775925e-01f,  0.00000000e+00f, -2.95083663e-02f,  0.00000000e+00f,  7.76323754e-02f },
+        { 5.00000000e-02f, -3.09016994e-02f,  0.00000000e+00f, -8.09016994e-02f,  6.45497224e-02f,  0.00000000e+00f, -5.59016994e-02f,  0.00000000e+00f,  7.21687836e-02f, -7.76323754e-02f,  0.00000000e+00f,  1.49775925e-01f,  0.00000000e+00f,  2.95083663e-02f,  0.00000000e+00f, -7.76323754e-02f },
+        { 5.00000000e-02f,  3.09016994e-02f,  0.00000000e+00f, -8.09016994e-02f, -6.45497224e-02f,  0.00000000e+00f, -5.59016994e-02f,  0.00000000e+00f,  7.21687836e-02f,  7.76323754e-02f,  0.00000000e+00f, -1.49775925e-01f,  0.00000000e+00f,  2.95083663e-02f,  0.00000000e+00f, -7.76323754e-02f },
+        { 5.00000000e-02f,  8.09016994e-02f,  3.09016994e-02f,  0.00000000e+00f,  0.00000000e+00f,  6.45497224e-02f, -3.45491503e-02f,  0.00000000e+00f, -8.44966837e-02f, -4.79794466e-02f,  0.00000000e+00f, -6.77901327e-02f,  3.03448665e-02f,  0.00000000e+00f, -1.65948192e-01f,  0.00000000e+00f },
+        { 5.00000000e-02f,  8.09016994e-02f, -3.09016994e-02f,  0.00000000e+00f,  0.00000000e+00f, -6.45497224e-02f, -3.45491503e-02f,  0.00000000e+00f, -8.44966837e-02f, -4.79794466e-02f,  0.00000000e+00f, -6.77901327e-02f, -3.03448665e-02f,  0.00000000e+00f,  1.65948192e-01f,  0.00000000e+00f },
+        { 5.00000000e-02f, -8.09016994e-02f, -3.09016994e-02f,  0.00000000e+00f,  0.00000000e+00f,  6.45497224e-02f, -3.45491503e-02f,  0.00000000e+00f, -8.44966837e-02f,  4.79794466e-02f,  0.00000000e+00f,  6.77901327e-02f, -3.03448665e-02f,  0.00000000e+00f,  1.65948192e-01f,  0.00000000e+00f },
+        { 5.00000000e-02f, -8.09016994e-02f,  3.09016994e-02f,  0.00000000e+00f,  0.00000000e+00f, -6.45497224e-02f, -3.45491503e-02f,  0.00000000e+00f, -8.44966837e-02f,  4.79794466e-02f,  0.00000000e+00f,  6.77901327e-02f,  3.03448665e-02f,  0.00000000e+00f, -1.65948192e-01f,  0.00000000e+00f },
+        { 5.00000000e-02f,  0.00000000e+00f,  8.09016994e-02f,  3.09016994e-02f,  0.00000000e+00f,  0.00000000e+00f,  9.04508497e-02f,  6.45497224e-02f,  1.23279000e-02f,  0.00000000e+00f,  0.00000000e+00f,  0.00000000e+00f,  7.94438918e-02f,  1.12611206e-01f, -2.42115150e-02f,  1.25611822e-01f },
+        { 5.00000000e-02f,  0.00000000e+00f, -8.09016994e-02f,  3.09016994e-02f,  0.00000000e+00f,  0.00000000e+00f,  9.04508497e-02f, -6.45497224e-02f,  1.23279000e-02f,  0.00000000e+00f,  0.00000000e+00f,  0.00000000e+00f, -7.94438918e-02f,  1.12611206e-01f,  2.42115150e-02f,  1.25611822e-01f },
+        { 5.00000000e-02f,  0.00000000e+00f, -8.09016994e-02f, -3.09016994e-02f,  0.00000000e+00f,  0.00000000e+00f,  9.04508497e-02f,  6.45497224e-02f,  1.23279000e-02f,  0.00000000e+00f,  0.00000000e+00f,  0.00000000e+00f, -7.94438918e-02f, -1.12611206e-01f,  2.42115150e-02f, -1.25611822e-01f },
+        { 5.00000000e-02f,  0.00000000e+00f,  8.09016994e-02f, -3.09016994e-02f,  0.00000000e+00f,  0.00000000e+00f,  9.04508497e-02f, -6.45497224e-02f,  1.23279000e-02f,  0.00000000e+00f,  0.00000000e+00f,  0.00000000e+00f,  7.94438918e-02f, -1.12611206e-01f, -2.42115150e-02f, -1.25611822e-01f }
     };
-    static constexpr ALfloat AmbiOrderHFGainFOA[MAX_AMBI_ORDER+1] = {
-        3.00000000e+00f, 1.73205081e+00f
-    }, AmbiOrderHFGainHOA[MAX_AMBI_ORDER+1] = {
-        2.40192231e+00f, 1.86052102e+00f, 9.60768923e-01f
+    static constexpr ALfloat AmbiOrderHFGainFOA[MAX_AMBI_ORDER+1]{
+        3.16227766e+00f, 1.82574186e+00f
+    }, AmbiOrderHFGainHOA[MAX_AMBI_ORDER+1]{
+        2.35702260e+00f, 1.82574186e+00f, 9.42809042e-01f
+        /* 1.86508671e+00f, 1.60609389e+00f, 1.14205530e+00f, 5.68379553e-01f */
     };
-    static constexpr ALsizei IndexMap[6] = { 0, 1, 2, 3, 4, 8 };
-    static constexpr ALsizei ChansPerOrder[MAX_AMBI_ORDER+1] = { 1, 3, 2, 0 };
-    const ALfloat (*RESTRICT AmbiMatrix)[MAX_AMBI_COEFFS] = AmbiMatrixFOA;
-    const ALfloat *RESTRICT AmbiOrderHFGain = AmbiOrderHFGainFOA;
+    static constexpr ALsizei IndexMap[9]{ 0, 1, 2, 3, 4, 5, 6, 7, 8 };
+    static constexpr ALsizei ChansPerOrder[MAX_AMBI_ORDER+1]{ 1, 3, 5, 0 };
+    const ALfloat *AmbiOrderHFGain{AmbiOrderHFGainFOA};
     ALsizei count{4};
 
-    static_assert(COUNTOF(AmbiPoints) == COUNTOF(AmbiMatrixFOA), "FOA Ambisonic HRTF mismatch");
-    static_assert(COUNTOF(AmbiPoints) == COUNTOF(AmbiMatrixHOA), "HOA Ambisonic HRTF mismatch");
+    static_assert(COUNTOF(AmbiPoints) == COUNTOF(AmbiMatrix), "Ambisonic HRTF mismatch");
 
     /* Don't bother with HOA when using full HRTF rendering. Nothing needs it,
      * and it eases the CPU/memory load.
@@ -698,7 +682,6 @@ void InitHrtfPanning(ALCdevice *device)
     {
         device->AmbiUp.reset(new AmbiUpsampler{});
 
-        AmbiMatrix = AmbiMatrixHOA;
         AmbiOrderHFGain = AmbiOrderHFGainHOA;
         count = static_cast<ALsizei>(COUNTOF(IndexMap));
     }