Add index maps from 2D and 3D

3 files changed, 30 insertions, 25 deletions

diff --git a/Alc/ambidefs.h b/Alc/ambidefs.h
index 82eb7ee3..eeb09f75 100644
--- a/Alc/ambidefs.h
+++ b/Alc/ambidefs.h
@@ -102,6 +102,14 @@ struct AmbiIndex {
         0,  1,  2,  3,  4,  5,  6,  7,
         8,  9, 10, 11, 12, 13, 14, 15
     }};
+
+    static constexpr std::array<int,MAX_AMBI2D_COEFFS> From2D{{
+        0, 1,3, 4,8, 9,15
+    }};
+    static constexpr std::array<int,MAX_AMBI_COEFFS> From3D{{
+        0,  1,  2,  3,  4,  5,  6,  7,
+        8,  9, 10, 11, 12, 13, 14, 15
+    }};
 };
 
 #endif /* AMBIDEFS_H */
diff --git a/Alc/bformatdec.cpp b/Alc/bformatdec.cpp
index 6a149611..d0d1325a 100644
--- a/Alc/bformatdec.cpp
+++ b/Alc/bformatdec.cpp
@@ -63,8 +63,6 @@ auto GetAmbiScales(AmbDecScale scaletype) noexcept -> const std::array<float,MAX
 
 void BFormatDec::reset(const AmbDecConf *conf, ALsizei chancount, ALuint srate, const ALsizei (&chanmap)[MAX_OUTPUT_CHANNELS])
 {
-    static constexpr ALsizei map2DTo3D[MAX_AMBI2D_COEFFS]{ 0,  1, 3,  4, 8,  9, 15 };
-
     mSamples.clear();
     mSamplesHF = nullptr;
     mSamplesLF = nullptr;
@@ -110,16 +108,16 @@ void BFormatDec::reset(const AmbDecConf *conf, ALsizei chancount, ALuint srate,
         {
             ALfloat coeffs[MAX_AMBI_COEFFS];
             CalcDirectionCoeffs(Ambi3DPoints[k], 0.0f, coeffs);
-            auto ambimap_end = std::begin(map2DTo3D) + chancount;
-            std::transform(std::begin(map2DTo3D), ambimap_end, std::begin(encgains[k]),
+            auto ambimap_end = AmbiIndex::From2D.begin() + chancount;
+            std::transform(AmbiIndex::From2D.begin(), ambimap_end, std::begin(encgains[k]),
                 [&coeffs](const ALsizei &index) noexcept -> ALfloat
-                { ASSUME(index > 0); return coeffs[index]; }
+                { ASSUME(index >= 0); return coeffs[index]; }
             );
         }
         assert(chancount >= 3);
         for(ALsizei c{0};c < 3;c++)
         {
-            const ALsizei i{map2DTo3D[c]};
+            const ALsizei i{AmbiIndex::From2D[c]};
             ALdouble gain{0.0};
             for(size_t k{0u};k < COUNTOF(Ambi3DDecoder);k++)
                 gain += (ALdouble)Ambi3DDecoder[k][i] * encgains[k][c];
@@ -142,7 +140,7 @@ void BFormatDec::reset(const AmbDecConf *conf, ALsizei chancount, ALuint srate,
             ALfloat (&mtx)[MAX_AMBI_COEFFS] = mMatrix.Single[chanmap[i]];
             for(ALsizei j{0},k{0};j < coeff_count;j++)
             {
-                const ALsizei l{periphonic ? j : map2DTo3D[j]};
+                const ALsizei l{periphonic ? j : AmbiIndex::From2D[j]};
                 if(!(conf->ChanMask&(1<<l))) continue;
                 mtx[j] = conf->HFMatrix[i][k] / coeff_scale[l] *
                     ((l>=9) ? conf->HFOrderGain[3] :
@@ -163,7 +161,7 @@ void BFormatDec::reset(const AmbDecConf *conf, ALsizei chancount, ALuint srate,
             ALfloat (&mtx)[sNumBands][MAX_AMBI_COEFFS] = mMatrix.Dual[chanmap[i]];
             for(ALsizei j{0},k{0};j < coeff_count;j++)
             {
-                const ALsizei l{periphonic ? j : map2DTo3D[j]};
+                const ALsizei l{periphonic ? j : AmbiIndex::From2D[j]};
                 if(!(conf->ChanMask&(1<<l))) continue;
                 mtx[HF_BAND][j] = conf->HFMatrix[i][k] / coeff_scale[l] *
                     ((l>=9) ? conf->HFOrderGain[3] :
diff --git a/Alc/panning.cpp b/Alc/panning.cpp
index 50d1eec2..d03977b8 100644
--- a/Alc/panning.cpp
+++ b/Alc/panning.cpp
@@ -47,6 +47,8 @@ constexpr std::array<float,MAX_AMBI_COEFFS> AmbiScale::FromSN3D;
 constexpr std::array<float,MAX_AMBI_COEFFS> AmbiScale::FromFuMa;
 constexpr std::array<int,MAX_AMBI_COEFFS> AmbiIndex::FromFuMa;
 constexpr std::array<int,MAX_AMBI_COEFFS> AmbiIndex::FromACN;
+constexpr std::array<int,MAX_AMBI2D_COEFFS> AmbiIndex::From2D;
+constexpr std::array<int,MAX_AMBI_COEFFS> AmbiIndex::From3D;
 
 
 namespace {
@@ -423,11 +425,8 @@ void InitPanning(ALCdevice *device)
         }
         else
         {
-            /* FOA output is always ACN+N3D for higher-order ambisonic output.
-             * The upsampler expects this and will convert it for output.
-             */
             device->FOAOut.Ambi = AmbiConfig{};
-            std::transform(AmbiIndex::FromACN.begin(), AmbiIndex::FromACN.begin()+4,
+            std::transform(AmbiIndex::From3D.begin(), AmbiIndex::From3D.begin()+4,
                 std::begin(device->FOAOut.Ambi.Map),
                 [](const ALsizei &acn) noexcept { return BFChannelConfig{1.0f, acn}; }
             );
@@ -462,7 +461,7 @@ void InitPanning(ALCdevice *device)
         else
         {
             device->FOAOut.Ambi = AmbiConfig{};
-            std::transform(AmbiIndex::FromACN.begin(), AmbiIndex::FromACN.begin()+4,
+            std::transform(AmbiIndex::From3D.begin(), AmbiIndex::From3D.begin()+4,
                 std::begin(device->FOAOut.Ambi.Map),
                 [](const ALsizei &acn) noexcept { return BFChannelConfig{1.0f, acn}; }
             );
@@ -513,11 +512,11 @@ void InitCustomPanning(ALCdevice *device, const AmbDecConf *conf, const ALsizei
     }
     else
     {
-        static constexpr int map[4] = { 0, 1, 2, 3 };
         static constexpr ALsizei count{4};
 
         device->FOAOut.Ambi = AmbiConfig{};
-        std::transform(std::begin(map), std::begin(map)+count, std::begin(device->FOAOut.Ambi.Map),
+        std::transform(AmbiIndex::From3D.begin(), AmbiIndex::From3D.begin()+count,
+            std::begin(device->FOAOut.Ambi.Map),
             [](const ALsizei &index) noexcept { return BFChannelConfig{1.0f, index}; }
         );
         device->FOAOut.CoeffCount = 0;
@@ -540,19 +539,19 @@ void InitHQPanning(ALCdevice *device, const AmbDecConf *conf, const ALsizei (&sp
     ALsizei count;
     if((conf->ChanMask&AMBI_PERIPHONIC_MASK))
     {
-        static constexpr int map[MAX_AMBI_COEFFS] = { 0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15 };
         count = (conf->ChanMask > AMBI_2ORDER_MASK) ? 16 :
                 (conf->ChanMask > AMBI_1ORDER_MASK) ? 9 : 4;
-        std::transform(std::begin(map), std::begin(map)+count, std::begin(device->Dry.Ambi.Map),
+        std::transform(AmbiIndex::From3D.begin(), AmbiIndex::From3D.begin()+count,
+            std::begin(device->Dry.Ambi.Map),
             [](const ALsizei &index) noexcept { return BFChannelConfig{1.0f, index}; }
         );
     }
     else
     {
-        static constexpr int map[MAX_AMBI2D_COEFFS] = { 0, 1, 3, 4, 8, 9, 15 };
         count = (conf->ChanMask > AMBI_2ORDER_MASK) ? 7 :
                 (conf->ChanMask > AMBI_1ORDER_MASK) ? 5 : 3;
-        std::transform(std::begin(map), std::begin(map)+count, std::begin(device->Dry.Ambi.Map),
+        std::transform(AmbiIndex::From2D.begin(), AmbiIndex::From2D.begin()+count,
+            std::begin(device->Dry.Ambi.Map),
             [](const ALsizei &index) noexcept { return BFChannelConfig{1.0f, index}; }
         );
     }
@@ -579,17 +578,17 @@ void InitHQPanning(ALCdevice *device, const AmbDecConf *conf, const ALsizei (&sp
         device->FOAOut.Ambi = AmbiConfig{};
         if((conf->ChanMask&AMBI_PERIPHONIC_MASK))
         {
-            static constexpr int map[4] = { 0, 1, 2, 3 };
             count = 4;
-            std::transform(std::begin(map), std::begin(map)+count, std::begin(device->FOAOut.Ambi.Map),
+            std::transform(AmbiIndex::From3D.begin(), AmbiIndex::From3D.begin()+count,
+                std::begin(device->FOAOut.Ambi.Map),
                 [](const ALsizei &index) noexcept { return BFChannelConfig{1.0f, index}; }
             );
         }
         else
         {
-            static constexpr int map[3] = { 0, 1, 3 };
             count = 3;
-            std::transform(std::begin(map), std::begin(map)+count, std::begin(device->FOAOut.Ambi.Map),
+            std::transform(AmbiIndex::From2D.begin(), AmbiIndex::From2D.begin()+count,
+                std::begin(device->FOAOut.Ambi.Map),
                 [](const ALsizei &index) noexcept { return BFChannelConfig{1.0f, index}; }
             );
         }
@@ -1145,8 +1144,8 @@ no_hrtf:
 void aluInitEffectPanning(ALeffectslot *slot)
 {
     const size_t count{countof(slot->ChanMap)};
-    auto acnmap_end = AmbiIndex::FromACN.begin() + count;
-    std::transform(AmbiIndex::FromACN.begin(), acnmap_end, std::begin(slot->ChanMap),
+    auto acnmap_end = AmbiIndex::From3D.begin() + count;
+    std::transform(AmbiIndex::From3D.begin(), acnmap_end, std::begin(slot->ChanMap),
         [](const ALsizei &acn) noexcept { return BFChannelConfig{1.0f, acn}; }
     );
     slot->NumChannels = static_cast<ALsizei>(count);