Remove dead code

1 files changed, 13 insertions, 92 deletions

diff --git a/alc/hrtf.cpp b/alc/hrtf.cpp
index f1e1a86b..05803865 100644
--- a/alc/hrtf.cpp
+++ b/alc/hrtf.cpp
@@ -289,13 +289,7 @@ void DirectHrtfState::build(const HrtfStore *Hrtf, const al::span<const AngularP
         ALuint ldelay, rdelay;
     };
 
-    /* Set this to true for dual-band HRTF processing. May require better
-     * calculation of the new IR length to deal with the head and tail
-     * generated by the HF scaling.
-     */
-    constexpr bool DualBand{false};
     const double xover_norm{400.0 / Hrtf->sampleRate};
-
     for(size_t i{0};i < mChannels.size();++i)
     {
         const size_t order{AmbiIndex::OrderFromChannel[i]};
@@ -303,8 +297,7 @@ void DirectHrtfState::build(const HrtfStore *Hrtf, const al::span<const AngularP
         mChannels[i].mHfScale = AmbiOrderHFGain[order];
     }
 
-    ALuint min_delay{HRTF_HISTORY_LENGTH*HRIR_DELAY_FRACONE};
-    ALuint max_delay{0};
+    ALuint min_delay{HRTF_HISTORY_LENGTH*HRIR_DELAY_FRACONE}, max_delay{0};
     al::vector<ImpulseResponse> impres; impres.reserve(AmbiPoints.size());
     auto calc_res = [Hrtf,&max_delay,&min_delay](const AngularPoint &pt) -> ImpulseResponse
     {
@@ -345,93 +338,25 @@ void DirectHrtfState::build(const HrtfStore *Hrtf, const al::span<const AngularP
     auto hrir_delay_round = [](const ALuint d) noexcept -> ALuint
     { return (d+HRIR_DELAY_FRACHALF) >> HRIR_DELAY_FRACBITS; };
 
-    /* For dual-band processing, add a 16-sample delay to compensate for the HF
-     * scale on the minimum-phase response.
-     */
-    constexpr ALuint base_delay{DualBand ? 16 : 0};
-    BandSplitterR<double> splitter{xover_norm};
-
     auto tmpres = al::vector<std::array<double2,HRIR_LENGTH>>(mChannels.size());
-    auto tmpflt = al::vector<std::array<double,HRIR_LENGTH*4>>(3);
-    const al::span<double,HRIR_LENGTH*4> tempir{tmpflt[2]};
     for(size_t c{0u};c < AmbiPoints.size();++c)
     {
         const HrirArray &hrir{impres[c].hrir};
-        const ALuint ldelay{hrir_delay_round(impres[c].ldelay-min_delay) + base_delay};
-        const ALuint rdelay{hrir_delay_round(impres[c].rdelay-min_delay) + base_delay};
-
-        if /*constexpr*/(!DualBand)
-        {
-            for(size_t i{0u};i < mChannels.size();++i)
-            {
-                const double mult{AmbiMatrix[c][i]};
-                const size_t numirs{HRIR_LENGTH - maxz(ldelay, rdelay)};
-                size_t lidx{ldelay}, ridx{rdelay};
-                for(size_t j{0};j < numirs;++j)
-                {
-                    tmpres[i][lidx++][0] += hrir[j][0] * mult;
-                    tmpres[i][ridx++][1] += hrir[j][1] * mult;
-                }
-            }
-            continue;
-        }
-
-        /* For dual-band processing, the HRIR needs to be split into low and
-         * high frequency responses. The band-splitter alone creates frequency-
-         * dependent phase-shifts, which is not ideal. To counteract it,
-         * combine it with a backwards phase-shift.
-         */
-
-        /* Load the (left) HRIR backwards, into a temp buffer with padding. */
-        std::fill(tempir.begin(), tempir.end(), 0.0);
-        std::transform(hrir.crbegin(), hrir.crend(), tempir.begin(),
-            [](const float2 &ir) noexcept -> double { return ir[0]; });
-
-        /* Apply the all-pass on the reversed signal and reverse the resulting
-         * sample array. This produces the forward response with a backwards
-         * phase-shift (+n degrees becomes -n degrees).
-         */
-        splitter.applyAllpass(tempir);
-        std::reverse(tempir.begin(), tempir.end());
-
-        /* Now apply the band-splitter. This applies the normal phase-shift,
-         * which cancels out with the backwards phase-shift to get the original
-         * phase on the split signal.
-         */
-        splitter.clear();
-        splitter.process(tempir, tmpflt[0].data(), tmpflt[1].data());
-
-        /* Apply left ear response with delay and HF scale. */
-        for(size_t i{0u};i < mChannels.size();++i)
-        {
-            const double mult{AmbiMatrix[c][i]};
-            const double hfgain{AmbiOrderHFGain[AmbiIndex::OrderFromChannel[i]]};
-            size_t j{tmpflt[0].size()-HRIR_LENGTH - ldelay};
-            for(size_t lidx{0};lidx < HRIR_LENGTH;++lidx,++j)
-                tmpres[i][lidx][0] += (tmpflt[0][j]*hfgain + tmpflt[1][j]) * mult;
-        }
-
-        /* Now run the same process on the right HRIR. */
-        std::fill(tempir.begin(), tempir.end(), 0.0);
-        std::transform(hrir.crbegin(), hrir.crend(), tempir.begin(),
-            [](const float2 &ir) noexcept -> double { return ir[1]; });
-
-        splitter.applyAllpass(tempir);
-        std::reverse(tempir.begin(), tempir.end());
-
-        splitter.clear();
-        splitter.process(tempir, tmpflt[0].data(), tmpflt[1].data());
+        const ALuint ldelay{hrir_delay_round(impres[c].ldelay - min_delay)};
+        const ALuint rdelay{hrir_delay_round(impres[c].rdelay - min_delay)};
 
         for(size_t i{0u};i < mChannels.size();++i)
         {
             const double mult{AmbiMatrix[c][i]};
-            const double hfgain{AmbiOrderHFGain[AmbiIndex::OrderFromChannel[i]]};
-            size_t j{tmpflt[0].size()-HRIR_LENGTH - rdelay};
-            for(size_t ridx{0};ridx < HRIR_LENGTH;++ridx,++j)
-                tmpres[i][ridx][1] += (tmpflt[0][j]*hfgain + tmpflt[1][j]) * mult;
+            const size_t numirs{HRIR_LENGTH - maxz(ldelay, rdelay)};
+            size_t lidx{ldelay}, ridx{rdelay};
+            for(size_t j{0};j < numirs;++j)
+            {
+                tmpres[i][lidx++][0] += hrir[j][0] * mult;
+                tmpres[i][ridx++][1] += hrir[j][1] * mult;
+            }
         }
     }
-    tmpflt.clear();
     impres.clear();
 
     for(size_t i{0u};i < mChannels.size();++i)
@@ -443,14 +368,10 @@ void DirectHrtfState::build(const HrtfStore *Hrtf, const al::span<const AngularP
     }
     tmpres.clear();
 
-    max_delay -= min_delay;
-    /* Increase the IR size by double the base delay with dual-band processing
-     * to account for the head and tail from the HF response scale.
-     */
-    const ALuint irsize{minu(Hrtf->irSize + base_delay*2, HRIR_LENGTH)};
-    const ALuint max_length{minu(hrir_delay_round(max_delay) + irsize, HRIR_LENGTH)};
+    max_delay = hrir_delay_round(max_delay - min_delay);
+    const ALuint max_length{minu(max_delay + Hrtf->irSize, HRIR_LENGTH)};
 
-    TRACE("Skipped delay: %.2f, max delay: %.2f, new FIR length: %u\n",
+    TRACE("Skipped delay: %.2f, new max delay: %.2f, FIR length: %u\n",
         min_delay/double{HRIR_DELAY_FRACONE}, max_delay/double{HRIR_DELAY_FRACONE},
         max_length);
     mIrSize = max_length;