/** * OpenAL cross platform audio library * Copyright (C) 2009 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 #include #include #include "alMain.h" #include "alcontext.h" #include "alFilter.h" #include "alAuxEffectSlot.h" #include "alError.h" #include "alu.h" #include "filters/biquad.h" #include "vector.h" struct ALechoState final : public EffectState { al::vector mSampleBuffer; // The echo is two tap. The delay is the number of samples from before the // current offset struct { ALsizei delay{0}; } mTap[2]; ALsizei mOffset{0}; /* The panning gains for the two taps */ struct { ALfloat Current[MAX_OUTPUT_CHANNELS]{}; ALfloat Target[MAX_OUTPUT_CHANNELS]{}; } mGains[2]; ALfloat mFeedGain{0.0f}; BiquadFilter mFilter; ALboolean deviceUpdate(const ALCdevice *device) override; void update(const ALCcontext *context, const ALeffectslot *slot, const ALeffectProps *props, const EffectTarget target) override; void process(ALsizei samplesToDo, const ALfloat (*RESTRICT samplesIn)[BUFFERSIZE], ALfloat (*RESTRICT samplesOut)[BUFFERSIZE], ALsizei numChannels) override; DEF_NEWDEL(ALechoState) }; ALboolean ALechoState::deviceUpdate(const ALCdevice *Device) { ALuint maxlen; // Use the next power of 2 for the buffer length, so the tap offsets can be // wrapped using a mask instead of a modulo maxlen = float2int(AL_ECHO_MAX_DELAY*Device->Frequency + 0.5f) + float2int(AL_ECHO_MAX_LRDELAY*Device->Frequency + 0.5f); maxlen = NextPowerOf2(maxlen); if(maxlen <= 0) return AL_FALSE; if(maxlen != mSampleBuffer.size()) { mSampleBuffer.resize(maxlen); mSampleBuffer.shrink_to_fit(); } std::fill(mSampleBuffer.begin(), mSampleBuffer.end(), 0.0f); for(auto &e : mGains) { std::fill(std::begin(e.Current), std::end(e.Current), 0.0f); std::fill(std::begin(e.Target), std::end(e.Target), 0.0f); } return AL_TRUE; } void ALechoState::update(const ALCcontext *context, const ALeffectslot *slot, const ALeffectProps *props, const EffectTarget target) { const ALCdevice *device = context->Device; ALuint frequency = device->Frequency; ALfloat gainhf, lrpan, spread; mTap[0].delay = maxi(float2int(props->Echo.Delay*frequency + 0.5f), 1); mTap[1].delay = float2int(props->Echo.LRDelay*frequency + 0.5f); mTap[1].delay += mTap[0].delay; spread = props->Echo.Spread; if(spread < 0.0f) lrpan = -1.0f; else lrpan = 1.0f; /* Convert echo spread (where 0 = omni, +/-1 = directional) to coverage * spread (where 0 = point, tau = omni). */ spread = asinf(1.0f - fabsf(spread))*4.0f; mFeedGain = props->Echo.Feedback; gainhf = maxf(1.0f - props->Echo.Damping, 0.0625f); /* Limit -24dB */ mFilter.setParams(BiquadType::HighShelf, gainhf, LOWPASSFREQREF/frequency, calc_rcpQ_from_slope(gainhf, 1.0f) ); ALfloat coeffs[2][MAX_AMBI_COEFFS]; CalcAngleCoeffs(al::MathDefs::Pi()*-0.5f*lrpan, 0.0f, spread, coeffs[0]); CalcAngleCoeffs(al::MathDefs::Pi()* 0.5f*lrpan, 0.0f, spread, coeffs[1]); mOutBuffer = target.Main->Buffer; mOutChannels = target.Main->NumChannels; ComputePanGains(target.Main, coeffs[0], slot->Params.Gain, mGains[0].Target); ComputePanGains(target.Main, coeffs[1], slot->Params.Gain, mGains[1].Target); } void ALechoState::process(ALsizei SamplesToDo, const ALfloat (*RESTRICT SamplesIn)[BUFFERSIZE], ALfloat (*RESTRICT SamplesOut)[BUFFERSIZE], ALsizei NumChannels) { const auto mask = static_cast(mSampleBuffer.size()-1); const ALsizei tap1{mTap[0].delay}; const ALsizei tap2{mTap[1].delay}; ALfloat *RESTRICT delaybuf{mSampleBuffer.data()}; ALsizei offset{mOffset}; ALfloat z1, z2; ALsizei base; ALsizei c, i; std::tie(z1, z2) = mFilter.getComponents(); for(base = 0;base < SamplesToDo;) { alignas(16) ALfloat temps[2][128]; ALsizei td = mini(128, SamplesToDo-base); for(i = 0;i < td;i++) { /* Feed the delay buffer's input first. */ delaybuf[offset&mask] = SamplesIn[0][i+base]; /* First tap */ temps[0][i] = delaybuf[(offset-tap1) & mask]; /* Second tap */ temps[1][i] = delaybuf[(offset-tap2) & mask]; /* Apply damping to the second tap, then add it to the buffer with * feedback attenuation. */ float out{mFilter.processOne(temps[1][i], z1, z2)}; delaybuf[offset&mask] += out * mFeedGain; offset++; } for(c = 0;c < 2;c++) MixSamples(temps[c], NumChannels, SamplesOut, mGains[c].Current, mGains[c].Target, SamplesToDo-base, base, td); base += td; } mFilter.setComponents(z1, z2); mOffset = offset; } struct EchoStateFactory final : public EffectStateFactory { EffectState *create() override; }; EffectState *EchoStateFactory::create() { return new ALechoState{}; } EffectStateFactory *EchoStateFactory_getFactory(void) { static EchoStateFactory EchoFactory{}; return &EchoFactory; } void ALecho_setParami(ALeffect *UNUSED(effect), ALCcontext *context, ALenum param, ALint UNUSED(val)) { alSetError(context, AL_INVALID_ENUM, "Invalid echo integer property 0x%04x", param); } void ALecho_setParamiv(ALeffect *UNUSED(effect), ALCcontext *context, ALenum param, const ALint *UNUSED(vals)) { alSetError(context, AL_INVALID_ENUM, "Invalid echo integer-vector property 0x%04x", param); } void ALecho_setParamf(ALeffect *effect, ALCcontext *context, ALenum param, ALfloat val) { ALeffectProps *props = &effect->Props; switch(param) { case AL_ECHO_DELAY: if(!(val >= AL_ECHO_MIN_DELAY && val <= AL_ECHO_MAX_DELAY)) SETERR_RETURN(context, AL_INVALID_VALUE,, "Echo delay out of range"); props->Echo.Delay = val; break; case AL_ECHO_LRDELAY: if(!(val >= AL_ECHO_MIN_LRDELAY && val <= AL_ECHO_MAX_LRDELAY)) SETERR_RETURN(context, AL_INVALID_VALUE,, "Echo LR delay out of range"); props->Echo.LRDelay = val; break; case AL_ECHO_DAMPING: if(!(val >= AL_ECHO_MIN_DAMPING && val <= AL_ECHO_MAX_DAMPING)) SETERR_RETURN(context, AL_INVALID_VALUE,, "Echo damping out of range"); props->Echo.Damping = val; break; case AL_ECHO_FEEDBACK: if(!(val >= AL_ECHO_MIN_FEEDBACK && val <= AL_ECHO_MAX_FEEDBACK)) SETERR_RETURN(context, AL_INVALID_VALUE,, "Echo feedback out of range"); props->Echo.Feedback = val; break; case AL_ECHO_SPREAD: if(!(val >= AL_ECHO_MIN_SPREAD && val <= AL_ECHO_MAX_SPREAD)) SETERR_RETURN(context, AL_INVALID_VALUE,, "Echo spread out of range"); props->Echo.Spread = val; break; default: alSetError(context, AL_INVALID_ENUM, "Invalid echo float property 0x%04x", param); } } void ALecho_setParamfv(ALeffect *effect, ALCcontext *context, ALenum param, const ALfloat *vals) { ALecho_setParamf(effect, context, param, vals[0]); } void ALecho_getParami(const ALeffect *UNUSED(effect), ALCcontext *context, ALenum param, ALint *UNUSED(val)) { alSetError(context, AL_INVALID_ENUM, "Invalid echo integer property 0x%04x", param); } void ALecho_getParamiv(const ALeffect *UNUSED(effect), ALCcontext *context, ALenum param, ALint *UNUSED(vals)) { alSetError(context, AL_INVALID_ENUM, "Invalid echo integer-vector property 0x%04x", param); } void ALecho_getParamf(const ALeffect *effect, ALCcontext *context, ALenum param, ALfloat *val) { const ALeffectProps *props = &effect->Props; switch(param) { case AL_ECHO_DELAY: *val = props->Echo.Delay; break; case AL_ECHO_LRDELAY: *val = props->Echo.LRDelay; break; case AL_ECHO_DAMPING: *val = props->Echo.Damping; break; case AL_ECHO_FEEDBACK: *val = props->Echo.Feedback; break; case AL_ECHO_SPREAD: *val = props->Echo.Spread; break; default: alSetError(context, AL_INVALID_ENUM, "Invalid echo float property 0x%04x", param); } } void ALecho_getParamfv(const ALeffect *effect, ALCcontext *context, ALenum param, ALfloat *vals) { ALecho_getParamf(effect, context, param, vals); } DEFINE_ALEFFECT_VTABLE(ALecho);