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Diffstat (limited to 'Alc/alcModulator.c')
| -rw-r--r-- | Alc/alcModulator.c | 204 |
1 files changed, 0 insertions, 204 deletions
diff --git a/Alc/alcModulator.c b/Alc/alcModulator.c deleted file mode 100644 index de062151..00000000 --- a/Alc/alcModulator.c +++ /dev/null @@ -1,204 +0,0 @@ -/** - * 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., 59 Temple Place - Suite 330, - * Boston, MA 02111-1307, USA. - * Or go to http://www.gnu.org/copyleft/lgpl.html - */ - -#include "config.h" - -#include <math.h> -#include <stdlib.h> - -#include "alMain.h" -#include "alFilter.h" -#include "alAuxEffectSlot.h" -#include "alError.h" -#include "alu.h" - - -typedef struct ALmodulatorState { - // Must be first in all effects! - ALeffectState state; - - enum { - SINUSOID, - SAWTOOTH, - SQUARE - } Waveform; - - ALuint index; - ALuint step; - - ALfloat Gain[MaxChannels]; - - FILTER iirFilter; - ALfloat history[1]; -} ALmodulatorState; - -#define WAVEFORM_FRACBITS 16 -#define WAVEFORM_FRACONE (1<<WAVEFORM_FRACBITS) -#define WAVEFORM_FRACMASK (WAVEFORM_FRACONE-1) - -static __inline ALfloat Sin(ALuint index) -{ - return sinf(index * (F_PI*2.0f / WAVEFORM_FRACONE)); -} - -static __inline ALfloat Saw(ALuint index) -{ - return index*(2.0f/WAVEFORM_FRACONE) - 1.0f; -} - -static __inline ALfloat Square(ALuint index) -{ - return ((index>>(WAVEFORM_FRACBITS-1))&1)*2.0f - 1.0f; -} - - -static __inline ALfloat hpFilter1P(FILTER *iir, ALuint offset, ALfloat input) -{ - ALfloat *history = &iir->history[offset]; - ALfloat a = iir->coeff; - ALfloat output = input; - - output = output + (history[0]-output)*a; - history[0] = output; - - return input - output; -} - - -#define DECL_TEMPLATE(func) \ -static void Process##func(ALmodulatorState *state, ALuint SamplesToDo, \ - const ALfloat *RESTRICT SamplesIn, \ - ALfloat (*RESTRICT SamplesOut)[BUFFERSIZE]) \ -{ \ - const ALuint step = state->step; \ - ALuint index = state->index; \ - ALfloat samp; \ - ALuint i, k; \ - \ - for(i = 0;i < SamplesToDo;i++) \ - { \ - samp = SamplesIn[i]; \ - \ - index += step; \ - index &= WAVEFORM_FRACMASK; \ - samp *= func(index); \ - \ - samp = hpFilter1P(&state->iirFilter, 0, samp); \ - \ - for(k = 0;k < MaxChannels;k++) \ - SamplesOut[k][i] += state->Gain[k] * samp; \ - } \ - state->index = index; \ -} - -DECL_TEMPLATE(Sin) -DECL_TEMPLATE(Saw) -DECL_TEMPLATE(Square) - -#undef DECL_TEMPLATE - - -static ALvoid ModulatorDestroy(ALeffectState *effect) -{ - ALmodulatorState *state = (ALmodulatorState*)effect; - free(state); -} - -static ALboolean ModulatorDeviceUpdate(ALeffectState *effect, ALCdevice *Device) -{ - return AL_TRUE; - (void)effect; - (void)Device; -} - -static ALvoid ModulatorUpdate(ALeffectState *effect, ALCdevice *Device, const ALeffectslot *Slot) -{ - ALmodulatorState *state = (ALmodulatorState*)effect; - ALfloat gain, cw, a = 0.0f; - ALuint index; - - if(Slot->effect.Modulator.Waveform == AL_RING_MODULATOR_SINUSOID) - state->Waveform = SINUSOID; - else if(Slot->effect.Modulator.Waveform == AL_RING_MODULATOR_SAWTOOTH) - state->Waveform = SAWTOOTH; - else if(Slot->effect.Modulator.Waveform == AL_RING_MODULATOR_SQUARE) - state->Waveform = SQUARE; - - state->step = fastf2u(Slot->effect.Modulator.Frequency*WAVEFORM_FRACONE / - Device->Frequency); - if(state->step == 0) state->step = 1; - - cw = cosf(F_PI*2.0f * Slot->effect.Modulator.HighPassCutoff / - Device->Frequency); - a = (2.0f-cw) - sqrtf(powf(2.0f-cw, 2.0f) - 1.0f); - state->iirFilter.coeff = a; - - gain = sqrtf(1.0f/Device->NumChan); - gain *= Slot->Gain; - for(index = 0;index < MaxChannels;index++) - state->Gain[index] = 0.0f; - for(index = 0;index < Device->NumChan;index++) - { - enum Channel chan = Device->Speaker2Chan[index]; - state->Gain[chan] = gain; - } -} - -static ALvoid ModulatorProcess(ALeffectState *effect, ALuint SamplesToDo, const ALfloat *RESTRICT SamplesIn, ALfloat (*RESTRICT SamplesOut)[BUFFERSIZE]) -{ - ALmodulatorState *state = (ALmodulatorState*)effect; - - switch(state->Waveform) - { - case SINUSOID: - ProcessSin(state, SamplesToDo, SamplesIn, SamplesOut); - break; - - case SAWTOOTH: - ProcessSaw(state, SamplesToDo, SamplesIn, SamplesOut); - break; - - case SQUARE: - ProcessSquare(state, SamplesToDo, SamplesIn, SamplesOut); - break; - } -} - -ALeffectState *ModulatorCreate(void) -{ - ALmodulatorState *state; - - state = malloc(sizeof(*state)); - if(!state) - return NULL; - - state->state.Destroy = ModulatorDestroy; - state->state.DeviceUpdate = ModulatorDeviceUpdate; - state->state.Update = ModulatorUpdate; - state->state.Process = ModulatorProcess; - - state->index = 0; - state->step = 1; - - state->iirFilter.coeff = 0.0f; - state->iirFilter.history[0] = 0.0f; - - return &state->state; -} |