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/**
* OpenAL cross platform audio library
* Copyright (C) 2011 by Chris Robinson
* This library is free software; you can redistribute it and/or
* modify it under the terms of the GNU Library General Public
* License as published by the Free Software Foundation; either
* version 2 of the License, or (at your option) any later version.
*
* This library is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
* Library General Public License for more details.
*
* You should have received a copy of the GNU Library General Public
* License along with this library; if not, write to the
* Free Software Foundation, Inc.,
* 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
* Or go to http://www.gnu.org/copyleft/lgpl.html
*/
#include "config.h"
#include <stdlib.h>
#include <ctype.h>
#include <mutex>
#include <array>
#include <vector>
#include <memory>
#include <istream>
#include <numeric>
#include <algorithm>
#include <functional>
#include "AL/al.h"
#include "AL/alc.h"
#include "alMain.h"
#include "alSource.h"
#include "alu.h"
#include "hrtf.h"
#include "alconfig.h"
#include "filters/splitter.h"
#include "compat.h"
#include "almalloc.h"
#include "alspan.h"
struct HrtfHandle {
std::unique_ptr<HrtfEntry> entry;
al::FlexArray<char> filename;
HrtfHandle(size_t fname_len) : filename{fname_len} { }
HrtfHandle(const HrtfHandle&) = delete;
HrtfHandle& operator=(const HrtfHandle&) = delete;
static std::unique_ptr<HrtfHandle> Create(size_t fname_len);
static constexpr size_t Sizeof(size_t length) noexcept
{
return maxz(sizeof(HrtfHandle),
al::FlexArray<char>::Sizeof(length, offsetof(HrtfHandle, filename)));
}
DEF_PLACE_NEWDEL()
};
std::unique_ptr<HrtfHandle> HrtfHandle::Create(size_t fname_len)
{
void *ptr{al_calloc(DEF_ALIGN, HrtfHandle::Sizeof(fname_len))};
return std::unique_ptr<HrtfHandle>{new (ptr) HrtfHandle{fname_len}};
}
namespace {
using namespace std::placeholders;
using HrtfHandlePtr = std::unique_ptr<HrtfHandle>;
/* Data set limits must be the same as or more flexible than those defined in
* the makemhr utility.
*/
#define MIN_IR_SIZE (8)
#define MAX_IR_SIZE (512)
#define MOD_IR_SIZE (2)
#define MIN_FD_COUNT (1)
#define MAX_FD_COUNT (16)
#define MIN_FD_DISTANCE (0.05f)
#define MAX_FD_DISTANCE (2.5f)
#define MIN_EV_COUNT (5)
#define MAX_EV_COUNT (128)
#define MIN_AZ_COUNT (1)
#define MAX_AZ_COUNT (128)
#define MAX_HRIR_DELAY (HRTF_HISTORY_LENGTH-1)
constexpr ALchar magicMarker00[8]{'M','i','n','P','H','R','0','0'};
constexpr ALchar magicMarker01[8]{'M','i','n','P','H','R','0','1'};
constexpr ALchar magicMarker02[8]{'M','i','n','P','H','R','0','2'};
/* First value for pass-through coefficients (remaining are 0), used for omni-
* directional sounds. */
constexpr ALfloat PassthruCoeff{0.707106781187f/*sqrt(0.5)*/};
std::mutex LoadedHrtfLock;
al::vector<HrtfHandlePtr> LoadedHrtfs;
class databuf final : public std::streambuf {
int_type underflow() override
{ return traits_type::eof(); }
pos_type seekoff(off_type offset, std::ios_base::seekdir whence, std::ios_base::openmode mode) override
{
if((mode&std::ios_base::out) || !(mode&std::ios_base::in))
return traits_type::eof();
char_type *cur;
switch(whence)
{
case std::ios_base::beg:
if(offset < 0 || offset > egptr()-eback())
return traits_type::eof();
cur = eback() + offset;
break;
case std::ios_base::cur:
if((offset >= 0 && offset > egptr()-gptr()) ||
(offset < 0 && -offset > gptr()-eback()))
return traits_type::eof();
cur = gptr() + offset;
break;
case std::ios_base::end:
if(offset > 0 || -offset > egptr()-eback())
return traits_type::eof();
cur = egptr() + offset;
break;
default:
return traits_type::eof();
}
setg(eback(), cur, egptr());
return cur - eback();
}
pos_type seekpos(pos_type pos, std::ios_base::openmode mode) override
{
// Simplified version of seekoff
if((mode&std::ios_base::out) || !(mode&std::ios_base::in))
return traits_type::eof();
if(pos < 0 || pos > egptr()-eback())
return traits_type::eof();
setg(eback(), eback() + static_cast<size_t>(pos), egptr());
return pos;
}
public:
databuf(const char_type *start, const char_type *end) noexcept
{
setg(const_cast<char_type*>(start), const_cast<char_type*>(start),
const_cast<char_type*>(end));
}
};
class idstream final : public std::istream {
databuf mStreamBuf;
public:
idstream(const char *start, const char *end)
: std::istream{nullptr}, mStreamBuf{start, end}
{ init(&mStreamBuf); }
};
struct IdxBlend { ALsizei idx; ALfloat blend; };
/* Calculate the elevation index given the polar elevation in radians. This
* will return an index between 0 and (evcount - 1).
*/
IdxBlend CalcEvIndex(ALsizei evcount, ALfloat ev)
{
ev = (al::MathDefs<float>::Pi()*0.5f + ev) * (evcount-1) / al::MathDefs<float>::Pi();
ALsizei idx{float2int(ev)};
return IdxBlend{mini(idx, evcount-1), ev-idx};
}
/* Calculate the azimuth index given the polar azimuth in radians. This will
* return an index between 0 and (azcount - 1).
*/
IdxBlend CalcAzIndex(ALsizei azcount, ALfloat az)
{
az = (al::MathDefs<float>::Tau()+az) * azcount / al::MathDefs<float>::Tau();
ALsizei idx{float2int(az)};
return IdxBlend{idx%azcount, az-idx};
}
} // namespace
/* Calculates static HRIR coefficients and delays for the given polar elevation
* and azimuth in radians. The coefficients are normalized.
*/
void GetHrtfCoeffs(const HrtfEntry *Hrtf, ALfloat elevation, ALfloat azimuth, ALfloat distance,
ALfloat spread, HrirArray<ALfloat> &coeffs, ALsizei (&delays)[2])
{
const ALfloat dirfact{1.0f - (spread / al::MathDefs<float>::Tau())};
const auto *field = Hrtf->field;
const auto *field_end = field + Hrtf->fdCount-1;
ALsizei ebase{0};
while(distance < field->distance && field != field_end)
{
ebase += field->evCount;
++field;
}
/* Claculate the elevation indinces. */
const auto elev0 = CalcEvIndex(field->evCount, elevation);
const ALsizei elev1_idx{mini(elev0.idx+1, field->evCount-1)};
const ALsizei ir0offset{Hrtf->elev[ebase + elev0.idx].irOffset};
const ALsizei ir1offset{Hrtf->elev[ebase + elev1_idx].irOffset};
/* Calculate azimuth indices. */
const auto az0 = CalcAzIndex(Hrtf->elev[ebase + elev0.idx].azCount, azimuth);
const auto az1 = CalcAzIndex(Hrtf->elev[ebase + elev1_idx].azCount, azimuth);
/* Calculate the HRIR indices to blend. */
ALsizei idx[4]{
ir0offset + az0.idx,
ir0offset + ((az0.idx+1) % Hrtf->elev[ebase + elev0.idx].azCount),
ir1offset + az1.idx,
ir1offset + ((az1.idx+1) % Hrtf->elev[ebase + elev1_idx].azCount)
};
/* Calculate bilinear blending weights, attenuated according to the
* directional panning factor.
*/
const ALfloat blend[4]{
(1.0f-elev0.blend) * (1.0f-az0.blend) * dirfact,
(1.0f-elev0.blend) * ( az0.blend) * dirfact,
( elev0.blend) * (1.0f-az1.blend) * dirfact,
( elev0.blend) * ( az1.blend) * dirfact
};
/* Calculate the blended HRIR delays. */
delays[0] = fastf2i(
Hrtf->delays[idx[0]][0]*blend[0] + Hrtf->delays[idx[1]][0]*blend[1] +
Hrtf->delays[idx[2]][0]*blend[2] + Hrtf->delays[idx[3]][0]*blend[3]
);
delays[1] = fastf2i(
Hrtf->delays[idx[0]][1]*blend[0] + Hrtf->delays[idx[1]][1]*blend[1] +
Hrtf->delays[idx[2]][1]*blend[2] + Hrtf->delays[idx[3]][1]*blend[3]
);
const ALsizei irSize{Hrtf->irSize};
ASSUME(irSize >= MIN_IR_SIZE);
/* Calculate the sample offsets for the HRIR indices. */
idx[0] *= irSize;
idx[1] *= irSize;
idx[2] *= irSize;
idx[3] *= irSize;
/* Calculate the blended HRIR coefficients. */
ALfloat *coeffout{al::assume_aligned<16>(&coeffs[0][0])};
coeffout[0] = PassthruCoeff * (1.0f-dirfact);
coeffout[1] = PassthruCoeff * (1.0f-dirfact);
std::fill(coeffout+2, coeffout + irSize*2, 0.0f);
for(ALsizei c{0};c < 4;c++)
{
const ALfloat *srccoeffs{al::assume_aligned<16>(Hrtf->coeffs[idx[c]])};
const ALfloat mult{blend[c]};
auto blend_coeffs = [mult](const ALfloat src, const ALfloat coeff) noexcept -> ALfloat
{ return src*mult + coeff; };
std::transform<const ALfloat*RESTRICT>(srccoeffs, srccoeffs + irSize*2, coeffout,
coeffout, blend_coeffs);
}
}
std::unique_ptr<DirectHrtfState> DirectHrtfState::Create(size_t num_chans)
{
void *ptr{al_calloc(16, DirectHrtfState::Sizeof(num_chans))};
return std::unique_ptr<DirectHrtfState>{new (ptr) DirectHrtfState{num_chans}};
}
void BuildBFormatHrtf(const HrtfEntry *Hrtf, DirectHrtfState *state, const ALsizei NumChannels, const AngularPoint *AmbiPoints, const ALfloat (*RESTRICT AmbiMatrix)[MAX_AMBI_CHANNELS], const size_t AmbiCount, const ALfloat *RESTRICT AmbiOrderHFGain)
{
static constexpr int OrderFromChan[MAX_AMBI_CHANNELS]{
0, 1,1,1, 2,2,2,2,2, 3,3,3,3,3,3,3,
};
/* 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.
*/
static constexpr bool DualBand{true};
ASSUME(NumChannels > 0);
ASSUME(AmbiCount > 0);
auto &field = Hrtf->field[0];
ALsizei min_delay{HRTF_HISTORY_LENGTH};
ALsizei max_delay{0};
auto idx = al::vector<ALsizei>(AmbiCount);
auto calc_idxs = [Hrtf,&field,&max_delay,&min_delay](const AngularPoint &pt) noexcept -> ALsizei
{
/* Calculate elevation index. */
const auto evidx = clampi(
static_cast<ALsizei>((90.0f+pt.Elev)*(field.evCount-1)/180.0f + 0.5f),
0, field.evCount-1);
const ALsizei azcount{Hrtf->elev[evidx].azCount};
const ALsizei iroffset{Hrtf->elev[evidx].irOffset};
/* Calculate azimuth index for this elevation. */
const auto azidx = static_cast<ALsizei>((360.0f+pt.Azim)*azcount/360.0f + 0.5f) % azcount;
/* Calculate the index for the impulse response. */
ALsizei idx{iroffset + azidx};
min_delay = mini(min_delay, mini(Hrtf->delays[idx][0], Hrtf->delays[idx][1]));
max_delay = maxi(max_delay, maxi(Hrtf->delays[idx][0], Hrtf->delays[idx][1]));
return idx;
};
std::transform(AmbiPoints, AmbiPoints+AmbiCount, idx.begin(), calc_idxs);
/* For dual-band processing, add a 12-sample delay to compensate for the HF
* scale on the minimum-phase response.
*/
static constexpr ALsizei base_delay{DualBand ? 12 : 0};
const ALdouble xover_norm{400.0 / Hrtf->sampleRate};
BandSplitterR<double> splitter{xover_norm};
SplitterAllpassR<double> allpass{xover_norm};
auto tmpres = al::vector<HrirArray<ALdouble>>(NumChannels);
auto tmpfilt = al::vector<std::array<ALdouble,HRIR_LENGTH*4>>(3);
for(size_t c{0u};c < AmbiCount;++c)
{
const ALfloat (*fir)[2]{&Hrtf->coeffs[idx[c] * Hrtf->irSize]};
const ALsizei ldelay{Hrtf->delays[idx[c]][0] - min_delay + base_delay};
const ALsizei rdelay{Hrtf->delays[idx[c]][1] - min_delay + base_delay};
if(!DualBand)
{
/* For single-band decoding, apply the HF scale to the response. */
for(ALsizei i{0};i < NumChannels;++i)
{
const ALdouble mult{ALdouble{AmbiOrderHFGain[OrderFromChan[i]]} *
AmbiMatrix[c][i]};
const ALsizei numirs{mini(Hrtf->irSize, HRIR_LENGTH-maxi(ldelay, rdelay))};
ALsizei lidx{ldelay}, ridx{rdelay};
for(ALsizei j{0};j < numirs;++j)
{
tmpres[i][lidx++][0] += fir[j][0] * mult;
tmpres[i][ridx++][1] += fir[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(tmpfilt[2].begin(), tmpfilt[2].end(), 0.0);
std::transform(fir, fir+Hrtf->irSize, tmpfilt[2].rbegin() + HRIR_LENGTH*3,
[](const ALfloat (&ir)[2]) noexcept -> ALdouble { 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).
*/
allpass.clear();
allpass.process(tmpfilt[2].data(), static_cast<int>(tmpfilt[2].size()));
std::reverse(tmpfilt[2].begin(), tmpfilt[2].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(tmpfilt[0].data(), tmpfilt[1].data(), tmpfilt[2].data(),
static_cast<int>(tmpfilt[2].size()));
/* Apply left ear response with delay and HF scale. */
for(ALsizei i{0};i < NumChannels;++i)
{
const ALdouble mult{AmbiMatrix[c][i]};
const ALdouble hfgain{AmbiOrderHFGain[OrderFromChan[i]]};
ALsizei j{HRIR_LENGTH*3 - ldelay};
for(ALsizei lidx{0};lidx < HRIR_LENGTH;++lidx,++j)
tmpres[i][lidx][0] += (tmpfilt[0][j]*hfgain + tmpfilt[1][j]) * mult;
}
/* Now run the same process on the right HRIR. */
std::fill(tmpfilt[2].begin(), tmpfilt[2].end(), 0.0);
std::transform(fir, fir+Hrtf->irSize, tmpfilt[2].rbegin() + HRIR_LENGTH*3,
[](const ALfloat (&ir)[2]) noexcept -> ALdouble { return ir[1]; });
allpass.clear();
allpass.process(tmpfilt[2].data(), static_cast<int>(tmpfilt[2].size()));
std::reverse(tmpfilt[2].begin(), tmpfilt[2].end());
splitter.clear();
splitter.process(tmpfilt[0].data(), tmpfilt[1].data(), tmpfilt[2].data(),
static_cast<int>(tmpfilt[2].size()));
for(ALsizei i{0};i < NumChannels;++i)
{
const ALdouble mult{AmbiMatrix[c][i]};
const ALdouble hfgain{AmbiOrderHFGain[OrderFromChan[i]]};
ALsizei j{HRIR_LENGTH*3 - rdelay};
for(ALsizei ridx{0};ridx < HRIR_LENGTH;++ridx,++j)
tmpres[i][ridx][1] += (tmpfilt[0][j]*hfgain + tmpfilt[1][j]) * mult;
}
}
tmpfilt.clear();
idx.clear();
for(ALsizei i{0};i < NumChannels;++i)
{
auto copy_arr = [](const std::array<double,2> &in) noexcept -> std::array<float,2>
{ return std::array<float,2>{{static_cast<float>(in[0]), static_cast<float>(in[1])}}; };
std::transform(tmpres[i].begin(), tmpres[i].end(), state->Chan[i].Coeffs.begin(),
copy_arr);
}
tmpres.clear();
ALsizei max_length{HRIR_LENGTH};
/* Increase the IR size by 24 samples with dual-band processing to account
* for the head and tail from the HF response scale.
*/
const ALsizei irsize{DualBand ? mini(Hrtf->irSize + base_delay*2, max_length) : Hrtf->irSize};
max_length = mini(max_delay-min_delay + irsize, max_length);
/* Round up to the next IR size multiple. */
max_length += MOD_IR_SIZE-1;
max_length -= max_length%MOD_IR_SIZE;
TRACE("Skipped delay: %d, max delay: %d, new FIR length: %d\n",
min_delay, max_delay-min_delay, max_length);
state->IrSize = max_length;
}
namespace {
std::unique_ptr<HrtfEntry> CreateHrtfStore(ALuint rate, ALsizei irSize, const ALsizei fdCount,
const ALubyte *evCount, const ALfloat *distance, const ALushort *azCount,
const ALushort *irOffset, ALsizei irCount, const ALfloat (*coeffs)[2],
const ALubyte (*delays)[2], const char *filename)
{
std::unique_ptr<HrtfEntry> Hrtf;
ALsizei evTotal{std::accumulate(evCount, evCount+fdCount, 0)};
size_t total{sizeof(HrtfEntry)};
total = RoundUp(total, alignof(HrtfEntry::Field)); /* Align for field infos */
total += sizeof(HrtfEntry::Field)*fdCount;
total = RoundUp(total, alignof(HrtfEntry::Elevation)); /* Align for elevation infos */
total += sizeof(Hrtf->elev[0])*evTotal;
total = RoundUp(total, 16); /* Align for coefficients using SIMD */
total += sizeof(Hrtf->coeffs[0])*irSize*irCount;
total += sizeof(Hrtf->delays[0])*irCount;
Hrtf.reset(new (al_calloc(16, total)) HrtfEntry{});
if(!Hrtf)
ERR("Out of memory allocating storage for %s.\n", filename);
else
{
InitRef(&Hrtf->ref, 1u);
Hrtf->sampleRate = rate;
Hrtf->irSize = irSize;
Hrtf->fdCount = fdCount;
/* Set up pointers to storage following the main HRTF struct. */
char *base = reinterpret_cast<char*>(Hrtf.get());
uintptr_t offset = sizeof(HrtfEntry);
offset = RoundUp(offset, alignof(HrtfEntry::Field)); /* Align for field infos */
auto field_ = reinterpret_cast<HrtfEntry::Field*>(base + offset);
offset += sizeof(field_[0])*fdCount;
offset = RoundUp(offset, alignof(HrtfEntry::Elevation)); /* Align for elevation infos */
auto elev_ = reinterpret_cast<HrtfEntry::Elevation*>(base + offset);
offset += sizeof(elev_[0])*evTotal;
offset = RoundUp(offset, 16); /* Align for coefficients using SIMD */
auto coeffs_ = reinterpret_cast<ALfloat(*)[2]>(base + offset);
offset += sizeof(coeffs_[0])*irSize*irCount;
auto delays_ = reinterpret_cast<ALubyte(*)[2]>(base + offset);
offset += sizeof(delays_[0])*irCount;
assert(offset == total);
/* Copy input data to storage. */
for(ALsizei i{0};i < fdCount;i++)
{
field_[i].distance = distance[i];
field_[i].evCount = evCount[i];
}
for(ALsizei i{0};i < evTotal;i++)
{
elev_[i].azCount = azCount[i];
elev_[i].irOffset = irOffset[i];
}
for(ALsizei i{0};i < irSize*irCount;i++)
{
coeffs_[i][0] = coeffs[i][0];
coeffs_[i][1] = coeffs[i][1];
}
for(ALsizei i{0};i < irCount;i++)
{
delays_[i][0] = delays[i][0];
delays_[i][1] = delays[i][1];
}
/* Finally, assign the storage pointers. */
Hrtf->field = field_;
Hrtf->elev = elev_;
Hrtf->coeffs = coeffs_;
Hrtf->delays = delays_;
}
return Hrtf;
}
ALubyte GetLE_ALubyte(std::istream &data)
{
return static_cast<ALubyte>(data.get());
}
ALshort GetLE_ALshort(std::istream &data)
{
int ret = data.get();
ret |= data.get() << 8;
return static_cast<ALshort>((ret^32768) - 32768);
}
ALushort GetLE_ALushort(std::istream &data)
{
int ret = data.get();
ret |= data.get() << 8;
return static_cast<ALushort>(ret);
}
ALint GetLE_ALint24(std::istream &data)
{
int ret = data.get();
ret |= data.get() << 8;
ret |= data.get() << 16;
return (ret^8388608) - 8388608;
}
ALuint GetLE_ALuint(std::istream &data)
{
int ret = data.get();
ret |= data.get() << 8;
ret |= data.get() << 16;
ret |= data.get() << 24;
return ret;
}
std::unique_ptr<HrtfEntry> LoadHrtf00(std::istream &data, const char *filename)
{
ALuint rate{GetLE_ALuint(data)};
ALushort irCount{GetLE_ALushort(data)};
ALushort irSize{GetLE_ALushort(data)};
ALubyte evCount{GetLE_ALubyte(data)};
if(!data || data.eof())
{
ERR("Failed reading %s\n", filename);
return nullptr;
}
ALboolean failed{AL_FALSE};
if(irSize < MIN_IR_SIZE || irSize > MAX_IR_SIZE || (irSize%MOD_IR_SIZE))
{
ERR("Unsupported HRIR size: irSize=%d (%d to %d by %d)\n",
irSize, MIN_IR_SIZE, MAX_IR_SIZE, MOD_IR_SIZE);
failed = AL_TRUE;
}
if(evCount < MIN_EV_COUNT || evCount > MAX_EV_COUNT)
{
ERR("Unsupported elevation count: evCount=%d (%d to %d)\n",
evCount, MIN_EV_COUNT, MAX_EV_COUNT);
failed = AL_TRUE;
}
if(failed)
return nullptr;
al::vector<ALushort> evOffset(evCount);
for(auto &val : evOffset)
val = GetLE_ALushort(data);
if(!data || data.eof())
{
ERR("Failed reading %s\n", filename);
return nullptr;
}
for(ALsizei i{1};i < evCount;i++)
{
if(evOffset[i] <= evOffset[i-1])
{
ERR("Invalid evOffset: evOffset[%d]=%d (last=%d)\n",
i, evOffset[i], evOffset[i-1]);
failed = AL_TRUE;
}
}
if(irCount <= evOffset.back())
{
ERR("Invalid evOffset: evOffset[%zu]=%d (irCount=%d)\n",
evOffset.size()-1, evOffset.back(), irCount);
failed = AL_TRUE;
}
if(failed)
return nullptr;
al::vector<ALushort> azCount(evCount);
for(ALsizei i{1};i < evCount;i++)
{
azCount[i-1] = evOffset[i] - evOffset[i-1];
if(azCount[i-1] < MIN_AZ_COUNT || azCount[i-1] > MAX_AZ_COUNT)
{
ERR("Unsupported azimuth count: azCount[%d]=%d (%d to %d)\n",
i-1, azCount[i-1], MIN_AZ_COUNT, MAX_AZ_COUNT);
failed = AL_TRUE;
}
}
azCount.back() = irCount - evOffset.back();
if(azCount.back() < MIN_AZ_COUNT || azCount.back() > MAX_AZ_COUNT)
{
ERR("Unsupported azimuth count: azCount[%zu]=%d (%d to %d)\n",
azCount.size()-1, azCount.back(), MIN_AZ_COUNT, MAX_AZ_COUNT);
failed = AL_TRUE;
}
if(failed)
return nullptr;
al::vector<std::array<ALfloat,2>> coeffs(irSize*irCount);
al::vector<std::array<ALubyte,2>> delays(irCount);
for(auto &val : coeffs)
val[0] = GetLE_ALshort(data) / 32768.0f;
for(auto &val : delays)
val[0] = GetLE_ALubyte(data);
if(!data || data.eof())
{
ERR("Failed reading %s\n", filename);
return nullptr;
}
for(ALsizei i{0};i < irCount;i++)
{
if(delays[i][0] > MAX_HRIR_DELAY)
{
ERR("Invalid delays[%d]: %d (%d)\n", i, delays[i][0], MAX_HRIR_DELAY);
failed = AL_TRUE;
}
}
if(failed)
return nullptr;
/* Mirror the left ear responses to the right ear. */
for(ALsizei i{0};i < evCount;i++)
{
ALushort evoffset = evOffset[i];
ALubyte azcount = azCount[i];
for(ALsizei j{0};j < azcount;j++)
{
ALsizei lidx = evoffset + j;
ALsizei ridx = evoffset + ((azcount-j) % azcount);
for(ALsizei k{0};k < irSize;k++)
coeffs[ridx*irSize + k][1] = coeffs[lidx*irSize + k][0];
delays[ridx][1] = delays[lidx][0];
}
}
static constexpr ALfloat distance{0.0f};
return CreateHrtfStore(rate, irSize, 1, &evCount, &distance, azCount.data(), evOffset.data(),
irCount, &reinterpret_cast<ALfloat(&)[2]>(coeffs[0]),
&reinterpret_cast<ALubyte(&)[2]>(delays[0]), filename);
}
std::unique_ptr<HrtfEntry> LoadHrtf01(std::istream &data, const char *filename)
{
ALuint rate{GetLE_ALuint(data)};
ALushort irSize{GetLE_ALubyte(data)};
ALubyte evCount{GetLE_ALubyte(data)};
if(!data || data.eof())
{
ERR("Failed reading %s\n", filename);
return nullptr;
}
ALboolean failed{AL_FALSE};
if(irSize < MIN_IR_SIZE || irSize > MAX_IR_SIZE || (irSize%MOD_IR_SIZE))
{
ERR("Unsupported HRIR size: irSize=%d (%d to %d by %d)\n",
irSize, MIN_IR_SIZE, MAX_IR_SIZE, MOD_IR_SIZE);
failed = AL_TRUE;
}
if(evCount < MIN_EV_COUNT || evCount > MAX_EV_COUNT)
{
ERR("Unsupported elevation count: evCount=%d (%d to %d)\n",
evCount, MIN_EV_COUNT, MAX_EV_COUNT);
failed = AL_TRUE;
}
if(failed)
return nullptr;
al::vector<ALushort> azCount(evCount);
std::generate(azCount.begin(), azCount.end(), std::bind(GetLE_ALubyte, std::ref(data)));
if(!data || data.eof())
{
ERR("Failed reading %s\n", filename);
return nullptr;
}
for(ALsizei i{0};i < evCount;++i)
{
if(azCount[i] < MIN_AZ_COUNT || azCount[i] > MAX_AZ_COUNT)
{
ERR("Unsupported azimuth count: azCount[%d]=%d (%d to %d)\n",
i, azCount[i], MIN_AZ_COUNT, MAX_AZ_COUNT);
failed = AL_TRUE;
}
}
if(failed)
return nullptr;
al::vector<ALushort> evOffset(evCount);
evOffset[0] = 0;
ALushort irCount{azCount[0]};
for(ALsizei i{1};i < evCount;i++)
{
evOffset[i] = evOffset[i-1] + azCount[i-1];
irCount += azCount[i];
}
al::vector<std::array<ALfloat,2>> coeffs(irSize*irCount);
al::vector<std::array<ALubyte,2>> delays(irCount);
for(auto &val : coeffs)
val[0] = GetLE_ALshort(data) / 32768.0f;
for(auto &val : delays)
val[0] = GetLE_ALubyte(data);
if(!data || data.eof())
{
ERR("Failed reading %s\n", filename);
return nullptr;
}
for(ALsizei i{0};i < irCount;i++)
{
if(delays[i][0] > MAX_HRIR_DELAY)
{
ERR("Invalid delays[%d]: %d (%d)\n", i, delays[i][0], MAX_HRIR_DELAY);
failed = AL_TRUE;
}
}
if(failed)
return nullptr;
/* Mirror the left ear responses to the right ear. */
for(ALsizei i{0};i < evCount;i++)
{
ALushort evoffset = evOffset[i];
ALubyte azcount = azCount[i];
for(ALsizei j{0};j < azcount;j++)
{
ALsizei lidx = evoffset + j;
ALsizei ridx = evoffset + ((azcount-j) % azcount);
for(ALsizei k{0};k < irSize;k++)
coeffs[ridx*irSize + k][1] = coeffs[lidx*irSize + k][0];
delays[ridx][1] = delays[lidx][0];
}
}
static constexpr ALfloat distance{0.0f};
return CreateHrtfStore(rate, irSize, 1, &evCount, &distance, azCount.data(), evOffset.data(),
irCount, &reinterpret_cast<ALfloat(&)[2]>(coeffs[0]),
&reinterpret_cast<ALubyte(&)[2]>(delays[0]), filename);
}
#define SAMPLETYPE_S16 0
#define SAMPLETYPE_S24 1
#define CHANTYPE_LEFTONLY 0
#define CHANTYPE_LEFTRIGHT 1
std::unique_ptr<HrtfEntry> LoadHrtf02(std::istream &data, const char *filename)
{
ALuint rate{GetLE_ALuint(data)};
ALubyte sampleType{GetLE_ALubyte(data)};
ALubyte channelType{GetLE_ALubyte(data)};
ALushort irSize{GetLE_ALubyte(data)};
ALubyte fdCount{GetLE_ALubyte(data)};
if(!data || data.eof())
{
ERR("Failed reading %s\n", filename);
return nullptr;
}
ALboolean failed{AL_FALSE};
if(sampleType > SAMPLETYPE_S24)
{
ERR("Unsupported sample type: %d\n", sampleType);
failed = AL_TRUE;
}
if(channelType > CHANTYPE_LEFTRIGHT)
{
ERR("Unsupported channel type: %d\n", channelType);
failed = AL_TRUE;
}
if(irSize < MIN_IR_SIZE || irSize > MAX_IR_SIZE || (irSize%MOD_IR_SIZE))
{
ERR("Unsupported HRIR size: irSize=%d (%d to %d by %d)\n",
irSize, MIN_IR_SIZE, MAX_IR_SIZE, MOD_IR_SIZE);
failed = AL_TRUE;
}
if(fdCount < 1 || fdCount > MAX_FD_COUNT)
{
ERR("Multiple field-depths not supported: fdCount=%d (%d to %d)\n",
fdCount, MIN_FD_COUNT, MAX_FD_COUNT);
failed = AL_TRUE;
}
if(failed)
return nullptr;
al::vector<ALfloat> distance(fdCount);
al::vector<ALubyte> evCount(fdCount);
al::vector<ALushort> azCount;
for(ALsizei f{0};f < fdCount;f++)
{
distance[f] = GetLE_ALushort(data) / 1000.0f;
evCount[f] = GetLE_ALubyte(data);
if(!data || data.eof())
{
ERR("Failed reading %s\n", filename);
return nullptr;
}
if(distance[f] < MIN_FD_DISTANCE || distance[f] > MAX_FD_DISTANCE)
{
ERR("Unsupported field distance[%d]=%f (%f to %f meters)\n", f,
distance[f], MIN_FD_DISTANCE, MAX_FD_DISTANCE);
failed = AL_TRUE;
}
if(f > 0 && distance[f] <= distance[f-1])
{
ERR("Field distance[%d] is not after previous (%f > %f)\n", f, distance[f],
distance[f-1]);
failed = AL_TRUE;
}
if(evCount[f] < MIN_EV_COUNT || evCount[f] > MAX_EV_COUNT)
{
ERR("Unsupported elevation count: evCount[%d]=%d (%d to %d)\n", f,
evCount[f], MIN_EV_COUNT, MAX_EV_COUNT);
failed = AL_TRUE;
}
if(failed)
return nullptr;
size_t ebase{azCount.size()};
azCount.resize(ebase + evCount[f]);
std::generate(azCount.begin()+ebase, azCount.end(),
std::bind(GetLE_ALubyte, std::ref(data)));
if(!data || data.eof())
{
ERR("Failed reading %s\n", filename);
return nullptr;
}
for(ALsizei e{0};e < evCount[f];e++)
{
if(azCount[ebase+e] < MIN_AZ_COUNT || azCount[ebase+e] > MAX_AZ_COUNT)
{
ERR("Unsupported azimuth count: azCount[%d][%d]=%d (%d to %d)\n", f, e,
azCount[ebase+e], MIN_AZ_COUNT, MAX_AZ_COUNT);
failed = AL_TRUE;
}
}
if(failed)
return nullptr;
}
al::vector<ALushort> evOffset(azCount.size());
evOffset[0] = 0;
std::partial_sum(azCount.cbegin(), azCount.cend()-1, evOffset.begin()+1);
const ALsizei irTotal{evOffset.back() + azCount.back()};
al::vector<std::array<ALfloat,2>> coeffs(irSize*irTotal);
al::vector<std::array<ALubyte,2>> delays(irTotal);
if(channelType == CHANTYPE_LEFTONLY)
{
if(sampleType == SAMPLETYPE_S16)
{
for(auto &val : coeffs)
val[0] = GetLE_ALshort(data) / 32768.0f;
}
else if(sampleType == SAMPLETYPE_S24)
{
for(auto &val : coeffs)
val[0] = GetLE_ALint24(data) / 8388608.0f;
}
for(auto &val : delays)
val[0] = GetLE_ALubyte(data);
if(!data || data.eof())
{
ERR("Failed reading %s\n", filename);
return nullptr;
}
for(ALsizei i{0};i < irTotal;++i)
{
if(delays[i][0] > MAX_HRIR_DELAY)
{
ERR("Invalid delays[%d][0]: %d (%d)\n", i, delays[i][0], MAX_HRIR_DELAY);
failed = AL_TRUE;
}
}
}
else if(channelType == CHANTYPE_LEFTRIGHT)
{
if(sampleType == SAMPLETYPE_S16)
{
for(auto &val : coeffs)
{
val[0] = GetLE_ALshort(data) / 32768.0f;
val[1] = GetLE_ALshort(data) / 32768.0f;
}
}
else if(sampleType == SAMPLETYPE_S24)
{
for(auto &val : coeffs)
{
val[0] = GetLE_ALint24(data) / 8388608.0f;
val[1] = GetLE_ALint24(data) / 8388608.0f;
}
}
for(auto &val : delays)
{
val[0] = GetLE_ALubyte(data);
val[1] = GetLE_ALubyte(data);
}
if(!data || data.eof())
{
ERR("Failed reading %s\n", filename);
return nullptr;
}
for(ALsizei i{0};i < irTotal;++i)
{
if(delays[i][0] > MAX_HRIR_DELAY)
{
ERR("Invalid delays[%d][0]: %d (%d)\n", i, delays[i][0], MAX_HRIR_DELAY);
failed = AL_TRUE;
}
if(delays[i][1] > MAX_HRIR_DELAY)
{
ERR("Invalid delays[%d][1]: %d (%d)\n", i, delays[i][1], MAX_HRIR_DELAY);
failed = AL_TRUE;
}
}
}
if(failed)
return nullptr;
if(channelType == CHANTYPE_LEFTONLY)
{
/* Mirror the left ear responses to the right ear. */
ALsizei ebase{0};
for(ALsizei f{0};f < fdCount;f++)
{
for(ALsizei e{0};e < evCount[f];e++)
{
ALushort evoffset = evOffset[ebase+e];
ALubyte azcount = azCount[ebase+e];
for(ALsizei a{0};a < azcount;a++)
{
ALsizei lidx = evoffset + a;
ALsizei ridx = evoffset + ((azcount-a) % azcount);
for(ALsizei k{0};k < irSize;k++)
coeffs[ridx*irSize + k][1] = coeffs[lidx*irSize + k][0];
delays[ridx][1] = delays[lidx][0];
}
}
ebase += evCount[f];
}
}
if(fdCount > 1)
{
auto distance_ = al::vector<ALfloat>(distance.size());
auto evCount_ = al::vector<ALubyte>(evCount.size());
auto azCount_ = al::vector<ALushort>(azCount.size());
auto evOffset_ = al::vector<ALushort>(evOffset.size());
auto coeffs_ = al::vector<float2>(coeffs.size());
auto delays_ = al::vector<std::array<ALubyte,2>>(delays.size());
/* Simple reverse for the per-field elements. */
std::reverse_copy(distance.cbegin(), distance.cend(), distance_.begin());
std::reverse_copy(evCount.cbegin(), evCount.cend(), evCount_.begin());
/* Each field has a group of elevations, which each have an azimuth
* count. Reverse the order of the groups, keeping the relative order
* of per-group azimuth counts.
*/
auto azcnt_end = azCount_.end();
auto copy_azs = [&azCount,&azcnt_end](const size_t ebase, const ALubyte num_evs) -> size_t
{
auto azcnt_src = azCount.begin()+ebase;
azcnt_end = std::copy_backward(azcnt_src, azcnt_src+num_evs, azcnt_end);
return ebase + num_evs;
};
std::accumulate(evCount.cbegin(), evCount.cend(), 0u, copy_azs);
assert(azCount_.begin() == azcnt_end);
/* Reestablish the IR offset for each elevation index, given the new
* ordering of elevations.
*/
evOffset_[0] = 0;
std::partial_sum(azCount_.cbegin(), azCount_.cend()-1, evOffset_.begin()+1);
/* Reverse the order of each field's group of IRs. */
auto coeffs_end = coeffs_.end();
auto delays_end = delays_.end();
auto copy_irs = [irSize,&azCount,&coeffs,&delays,&coeffs_end,&delays_end](const size_t ebase, const ALubyte num_evs) -> size_t
{
const ALsizei abase{std::accumulate(azCount.cbegin(), azCount.cbegin()+ebase, 0)};
const ALsizei num_azs{std::accumulate(azCount.cbegin()+ebase,
azCount.cbegin() + (ebase+num_evs), 0)};
coeffs_end = std::copy_backward(coeffs.cbegin() + abase*irSize,
coeffs.cbegin() + (abase+num_azs)*irSize, coeffs_end);
delays_end = std::copy_backward(delays.cbegin() + abase,
delays.cbegin() + (abase+num_azs), delays_end);
return ebase + num_evs;
};
std::accumulate(evCount.cbegin(), evCount.cend(), 0u, copy_irs);
assert(coeffs_.begin() == coeffs_end);
assert(delays_.begin() == delays_end);
distance = std::move(distance_);
evCount = std::move(evCount_);
azCount = std::move(azCount_);
evOffset = std::move(evOffset_);
coeffs = std::move(coeffs_);
delays = std::move(delays_);
}
return CreateHrtfStore(rate, irSize, fdCount, evCount.data(), distance.data(), azCount.data(),
evOffset.data(), irTotal, &reinterpret_cast<ALfloat(&)[2]>(coeffs[0]),
&reinterpret_cast<ALubyte(&)[2]>(delays[0]), filename);
}
bool checkName(al::vector<EnumeratedHrtf> &list, const std::string &name)
{
return std::find_if(list.cbegin(), list.cend(),
[&name](const EnumeratedHrtf &entry)
{ return name == entry.name; }
) != list.cend();
}
void AddFileEntry(al::vector<EnumeratedHrtf> &list, const std::string &filename)
{
/* Check if this file has already been loaded globally. */
auto loaded_entry = LoadedHrtfs.begin();
for(;loaded_entry != LoadedHrtfs.end();++loaded_entry)
{
if(filename != (*loaded_entry)->filename.data())
continue;
/* Check if this entry has already been added to the list. */
auto iter = std::find_if(list.cbegin(), list.cend(),
[loaded_entry](const EnumeratedHrtf &entry) -> bool
{ return loaded_entry->get() == entry.hrtf; }
);
if(iter != list.cend())
{
TRACE("Skipping duplicate file entry %s\n", filename.c_str());
return;
}
break;
}
if(loaded_entry == LoadedHrtfs.end())
{
TRACE("Got new file \"%s\"\n", filename.c_str());
LoadedHrtfs.emplace_back(HrtfHandle::Create(filename.length()+1));
loaded_entry = LoadedHrtfs.end()-1;
strcpy((*loaded_entry)->filename.data(), filename.c_str());
}
/* TODO: Get a human-readable name from the HRTF data (possibly coming in a
* format update). */
size_t namepos = filename.find_last_of('/')+1;
if(!namepos) namepos = filename.find_last_of('\\')+1;
size_t extpos{filename.find_last_of('.')};
if(extpos <= namepos) extpos = std::string::npos;
const std::string basename{(extpos == std::string::npos) ?
filename.substr(namepos) : filename.substr(namepos, extpos-namepos)};
std::string newname{basename};
int count{1};
while(checkName(list, newname))
{
newname = basename;
newname += " #";
newname += std::to_string(++count);
}
list.emplace_back(EnumeratedHrtf{newname, loaded_entry->get()});
const EnumeratedHrtf &entry = list.back();
TRACE("Adding file entry \"%s\"\n", entry.name.c_str());
}
/* Unfortunate that we have to duplicate AddFileEntry to take a memory buffer
* for input instead of opening the given filename.
*/
void AddBuiltInEntry(al::vector<EnumeratedHrtf> &list, const std::string &filename, ALuint residx)
{
auto loaded_entry = LoadedHrtfs.begin();
for(;loaded_entry != LoadedHrtfs.end();++loaded_entry)
{
if(filename != (*loaded_entry)->filename.data())
continue;
/* Check if this entry has already been added to the list. */
auto iter = std::find_if(list.cbegin(), list.cend(),
[loaded_entry](const EnumeratedHrtf &entry) -> bool
{ return loaded_entry->get() == entry.hrtf; }
);
if(iter != list.cend())
{
TRACE("Skipping duplicate file entry %s\n", filename.c_str());
return;
}
break;
}
if(loaded_entry == LoadedHrtfs.end())
{
TRACE("Got new file \"%s\"\n", filename.c_str());
LoadedHrtfs.emplace_back(HrtfHandle::Create(filename.length()+32));
loaded_entry = LoadedHrtfs.end()-1;
snprintf((*loaded_entry)->filename.data(), (*loaded_entry)->filename.size(), "!%u_%s",
residx, filename.c_str());
}
/* TODO: Get a human-readable name from the HRTF data (possibly coming in a
* format update). */
std::string newname{filename};
int count{1};
while(checkName(list, newname))
{
newname = filename;
newname += " #";
newname += std::to_string(++count);
}
list.emplace_back(EnumeratedHrtf{newname, loaded_entry->get()});
const EnumeratedHrtf &entry = list.back();
TRACE("Adding built-in entry \"%s\"\n", entry.name.c_str());
}
#define IDR_DEFAULT_44100_MHR 1
#define IDR_DEFAULT_48000_MHR 2
using ResData = al::span<const char>;
#ifndef ALSOFT_EMBED_HRTF_DATA
ResData GetResource(int UNUSED(name))
{ return ResData{}; }
#else
#include "default-44100.mhr.h"
#include "default-48000.mhr.h"
ResData GetResource(int name)
{
if(name == IDR_DEFAULT_44100_MHR)
return {reinterpret_cast<const char*>(hrtf_default_44100), sizeof(hrtf_default_44100)};
if(name == IDR_DEFAULT_48000_MHR)
return {reinterpret_cast<const char*>(hrtf_default_48000), sizeof(hrtf_default_48000)};
return ResData{};
}
#endif
} // namespace
al::vector<EnumeratedHrtf> EnumerateHrtf(const char *devname)
{
al::vector<EnumeratedHrtf> list;
bool usedefaults{true};
const char *pathlist{""};
if(ConfigValueStr(devname, nullptr, "hrtf-paths", &pathlist))
{
while(pathlist && *pathlist)
{
const char *next, *end;
while(isspace(*pathlist) || *pathlist == ',')
pathlist++;
if(*pathlist == '\0')
continue;
next = strchr(pathlist, ',');
if(next)
end = next++;
else
{
end = pathlist + strlen(pathlist);
usedefaults = false;
}
while(end != pathlist && isspace(*(end-1)))
--end;
if(end != pathlist)
{
const std::string pname{pathlist, end};
for(const auto &fname : SearchDataFiles(".mhr", pname.c_str()))
AddFileEntry(list, fname);
}
pathlist = next;
}
}
else if(ConfigValueExists(devname, nullptr, "hrtf_tables"))
ERR("The hrtf_tables option is deprecated, please use hrtf-paths instead.\n");
if(usedefaults)
{
for(const auto &fname : SearchDataFiles(".mhr", "openal/hrtf"))
AddFileEntry(list, fname);
if(!GetResource(IDR_DEFAULT_44100_MHR).empty())
AddBuiltInEntry(list, "Built-In 44100hz", IDR_DEFAULT_44100_MHR);
if(!GetResource(IDR_DEFAULT_48000_MHR).empty())
AddBuiltInEntry(list, "Built-In 48000hz", IDR_DEFAULT_48000_MHR);
}
const char *defaulthrtf{""};
if(!list.empty() && ConfigValueStr(devname, nullptr, "default-hrtf", &defaulthrtf))
{
auto iter = std::find_if(list.begin(), list.end(),
[defaulthrtf](const EnumeratedHrtf &entry) -> bool
{ return entry.name == defaulthrtf; }
);
if(iter == list.end())
WARN("Failed to find default HRTF \"%s\"\n", defaulthrtf);
else if(iter != list.begin())
{
EnumeratedHrtf entry{*iter};
list.erase(iter);
list.insert(list.begin(), entry);
}
}
return list;
}
HrtfEntry *GetLoadedHrtf(HrtfHandle *handle)
{
std::lock_guard<std::mutex> _{LoadedHrtfLock};
if(handle->entry)
{
HrtfEntry *hrtf{handle->entry.get()};
hrtf->IncRef();
return hrtf;
}
std::unique_ptr<std::istream> stream;
const char *name{""};
ALuint residx{};
char ch{};
if(sscanf(handle->filename.data(), "!%u%c", &residx, &ch) == 2 && ch == '_')
{
name = strchr(handle->filename.data(), ch)+1;
TRACE("Loading %s...\n", name);
ResData res{GetResource(residx)};
if(res.empty())
{
ERR("Could not get resource %u, %s\n", residx, name);
return nullptr;
}
stream = al::make_unique<idstream>(res.begin(), res.end());
}
else
{
name = handle->filename.data();
TRACE("Loading %s...\n", handle->filename.data());
auto fstr = al::make_unique<al::ifstream>(handle->filename.data(), std::ios::binary);
if(!fstr->is_open())
{
ERR("Could not open %s\n", handle->filename.data());
return nullptr;
}
stream = std::move(fstr);
}
std::unique_ptr<HrtfEntry> hrtf;
char magic[sizeof(magicMarker02)];
stream->read(magic, sizeof(magic));
if(stream->gcount() < static_cast<std::streamsize>(sizeof(magicMarker02)))
ERR("%s data is too short (%zu bytes)\n", name, stream->gcount());
else if(memcmp(magic, magicMarker02, sizeof(magicMarker02)) == 0)
{
TRACE("Detected data set format v2\n");
hrtf = LoadHrtf02(*stream, name);
}
else if(memcmp(magic, magicMarker01, sizeof(magicMarker01)) == 0)
{
TRACE("Detected data set format v1\n");
hrtf = LoadHrtf01(*stream, name);
}
else if(memcmp(magic, magicMarker00, sizeof(magicMarker00)) == 0)
{
TRACE("Detected data set format v0\n");
hrtf = LoadHrtf00(*stream, name);
}
else
ERR("Invalid header in %s: \"%.8s\"\n", name, magic);
stream.reset();
if(!hrtf)
{
ERR("Failed to load %s\n", name);
return nullptr;
}
TRACE("Loaded HRTF support for format: %s %uhz\n",
DevFmtChannelsString(DevFmtStereo), hrtf->sampleRate);
handle->entry = std::move(hrtf);
return handle->entry.get();
}
void HrtfEntry::IncRef()
{
auto ref = IncrementRef(&this->ref);
TRACEREF("%p increasing refcount to %u\n", this, ref);
}
void HrtfEntry::DecRef()
{
auto ref = DecrementRef(&this->ref);
TRACEREF("%p decreasing refcount to %u\n", this, ref);
if(ref == 0)
{
std::lock_guard<std::mutex> _{LoadedHrtfLock};
/* Need to double-check that it's still unused, as another device
* could've reacquired this HRTF after its reference went to 0 and
* before the lock was taken.
*/
auto iter = std::find_if(LoadedHrtfs.begin(), LoadedHrtfs.end(),
[this](const HrtfHandlePtr &entry) noexcept -> bool
{ return this == entry->entry.get(); }
);
if(iter != LoadedHrtfs.end() && ReadRef(&this->ref) == 0)
{
(*iter)->entry = nullptr;
TRACE("Unloaded unused HRTF %s\n", (*iter)->filename.data());
}
}
}