tap-lv2-cab6e0d/reverb/tap_reverb.c

/*                                                     -*- linux-c -*-
    Copyright (C) 2004 Tom Szilagyi

    This program is free software; you can redistribute it and/or modify
    it under the terms of the GNU General Public License as published by
    the Free Software Foundation; either version 2 of the License, or
    (at your option) any later version.

    This program 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 General Public License for more details.

    You should have received a copy of the GNU General Public License
    along with this program; if not, write to the Free Software
    Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.

    $Id: tap_reverb.c,v 1.13 2004/06/15 14:50:55 tszilagyi Exp $
*/


#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <math.h>
#include <lv2.h>


/* ***** VERY IMPORTANT! *****
 *
 * If you enable this, the plugin will use float arithmetics in DSP
 * calculations.  This usually yields lower average CPU usage, but
 * occasionaly may result in high CPU peaks which cause trouble to you
 * and your JACK server.  The default is to use fixpoint arithmetics
 * (with the following #define commented out).  But (depending on the
 * processor on which you run the code) you may find floating point
 * mode usable.
 */
/* #define REVERB_CALC_FLOAT */


#ifndef REVERB_CALC_FLOAT
typedef signed int sample;
#endif

#ifndef REVERB_CALC_FLOAT
typedef sample rev_t;
#else
typedef float rev_t;
#endif


#include "tap_reverb_presets.h"


#ifdef REVERB_CALC_FLOAT
#define DENORM(x) (((unsigned char)(((*(unsigned int*)&(x))&0x7f800000)>>23))<103)?0.0f:(x)
#else
/* coefficient for float to sample (signed int) conversion */
/* this allows for about 60 dB headroom above 0dB, if 0 dB is equivalent to 1.0f */
/* As 2^31 equals more than 180 dB, about 120 dB dynamics remains below 0 dB */
#define F2S 2147483
#endif


/* load plugin data from reverb_data[] into an instance */
void
load_plugin_data(LV2_Handle Instance) {

    Reverb * ptr = (Reverb *)Instance;
    unsigned long m;
    int i;


    m = LIMIT(*(ptr->mode),0,NUM_MODES-1);

    /* load combs data */
    ptr->num_combs = 2 * reverb_data[m].num_combs;
    for (i = 0; i < reverb_data[m].num_combs; i++) {
        ((COMB_FILTER *)(ptr->combs + 2*i))->buflen =
            reverb_data[m].combs[i].delay * ptr->sample_rate;
        ((COMB_FILTER *)(ptr->combs + 2*i))->feedback =
            reverb_data[m].combs[i].feedback;
        ((COMB_FILTER *)(ptr->combs + 2*i))->freq_resp =
            LIMIT(reverb_data[m].combs[i].freq_resp
                  * powf(ptr->sample_rate / 44100.0f, 0.8f),
                  0.0f, 1.0f);

        ((COMB_FILTER *)(ptr->combs + 2*i+1))->buflen =
            ((COMB_FILTER *)(ptr->combs + 2*i))->buflen;
        ((COMB_FILTER *)(ptr->combs + 2*i+1))->feedback =
            ((COMB_FILTER *)(ptr->combs + 2*i))->feedback;
        ((COMB_FILTER *)(ptr->combs + 2*i+1))->feedback =
            ((COMB_FILTER *)(ptr->combs + 2*i))->freq_resp;

        /* set initial values: */
        *(((COMB_FILTER *)(ptr->combs + 2*i))->buffer_pos) = 0;
        *(((COMB_FILTER *)(ptr->combs + 2*i+1))->buffer_pos) = 0;
        ((COMB_FILTER *)(ptr->combs + 2*i))->last_out = 0;
        ((COMB_FILTER *)(ptr->combs + 2*i+1))->last_out = 0;

        lp_set_params(((COMB_FILTER *)(ptr->combs + 2*i))->filter,
                  2000.0f + 13000.0f * (1 - reverb_data[m].combs[i].freq_resp)
                  * ptr->sample_rate / 44100.0f,
                  BANDPASS_BWIDTH, ptr->sample_rate);
        lp_set_params(((COMB_FILTER *)(ptr->combs + 2*i+1))->filter,
                  2000.0f + 13000.0f * (1 - reverb_data[m].combs[i].freq_resp)
                  * ptr->sample_rate / 44100.0f,
                  BANDPASS_BWIDTH, ptr->sample_rate);
    }

    /* load allps data */
    ptr->num_allps = 2 * reverb_data[m].num_allps;
    for (i = 0; i < reverb_data[m].num_allps; i++) {
        ((ALLP_FILTER *)(ptr->allps + 2*i))->buflen =
            reverb_data[m].allps[i].delay * ptr->sample_rate;
        ((ALLP_FILTER *)(ptr->allps + 2*i))->feedback =
            reverb_data[m].allps[i].feedback;

        ((ALLP_FILTER *)(ptr->allps + 2*i+1))->buflen =
            ((ALLP_FILTER *)(ptr->allps + 2*i))->buflen;
        ((ALLP_FILTER *)(ptr->allps + 2*i+1))->feedback =
            ((ALLP_FILTER *)(ptr->allps + 2*i))->feedback;

        /* set initial values: */
        *(((ALLP_FILTER *)(ptr->allps + 2*i))->buffer_pos) = 0;
        *(((ALLP_FILTER *)(ptr->allps + 2*i+1))->buffer_pos) = 0;
        ((ALLP_FILTER *)(ptr->allps + 2*i))->last_out = 0;
        ((ALLP_FILTER *)(ptr->allps + 2*i+1))->last_out = 0;
    }

    /* init bandpass filters */
    lp_set_params((biquad *)(ptr->low_pass), reverb_data[m].bandpass_high,
              BANDPASS_BWIDTH, ptr->sample_rate);
    hp_set_params((biquad *)(ptr->high_pass), reverb_data[m].bandpass_low,
              BANDPASS_BWIDTH, ptr->sample_rate);
    lp_set_params((biquad *)(ptr->low_pass + 1), reverb_data[m].bandpass_high,
              BANDPASS_BWIDTH, ptr->sample_rate);
    hp_set_params((biquad *)(ptr->high_pass + 1), reverb_data[m].bandpass_low,
              BANDPASS_BWIDTH, ptr->sample_rate);
}


/* push a sample into a comb filter and return the sample falling out */
rev_t
comb_run(rev_t insample, COMB_FILTER * comb) {

    rev_t outsample;
    rev_t pushin;

    pushin = comb->fb_gain * insample + biquad_run(comb->filter, comb->fb_gain * comb->last_out);
#ifdef REVERB_CALC_FLOAT
    pushin = DENORM(pushin);
#endif
    outsample = push_buffer(pushin,
                comb->ringbuffer, comb->buflen, comb->buffer_pos);
#ifdef REVERB_CALC_FLOAT
    outsample = DENORM(outsample);
#endif
    comb->last_out = outsample;

    return outsample;
}


/* push a sample into an allpass filter and return the sample falling out */
rev_t
allp_run(rev_t insample, ALLP_FILTER * allp) {

    rev_t outsample;
    rev_t pushin;
    pushin = allp->in_gain * allp->fb_gain * insample + allp->fb_gain * allp->last_out;
#ifdef REVERB_CALC_FLOAT
    pushin = DENORM(pushin);
#endif
    outsample = push_buffer(pushin,
                allp->ringbuffer, allp->buflen, allp->buffer_pos);
#ifdef REVERB_CALC_FLOAT
    outsample = DENORM(outsample);
#endif
    allp->last_out = outsample;

    return outsample;
}


/* compute user-input-dependent reverberator coefficients */
void
comp_coeffs(LV2_Handle Instance) {

    Reverb * ptr = (Reverb *)Instance;
    int i;


    if (*(ptr->mode) != ptr->old_mode)
        load_plugin_data(Instance);

    for (i = 0; i < ptr->num_combs / 2; i++) {
        ((COMB_FILTER *)(ptr->combs + 2*i))->fb_gain =
            powf(0.001f,
                 1000.0f * ((COMB_FILTER *)(ptr->combs + 2*i))->buflen
                 * (1 + FR_R_COMP * ((COMB_FILTER *)(ptr->combs + 2*i))->freq_resp)
                 / powf(((COMB_FILTER *)(ptr->combs + 2*i))->feedback/100.0f, 0.89f)
                 / *(ptr->decay)
                 / ptr->sample_rate);

        ((COMB_FILTER *)(ptr->combs + 2*i+1))->fb_gain =
            ((COMB_FILTER *)(ptr->combs + 2*i))->fb_gain;

        if (*(ptr->stereo_enh) > 0.0f) {
            if (i % 2 == 0)
                ((COMB_FILTER *)(ptr->combs + 2*i+1))->buflen =
                    ENH_STEREO_RATIO * ((COMB_FILTER *)(ptr->combs + 2*i))->buflen;
            else
                ((COMB_FILTER *)(ptr->combs + 2*i))->buflen =
                    ENH_STEREO_RATIO * ((COMB_FILTER *)(ptr->combs + 2*i+1))->buflen;
        } else {
            if (i % 2 == 0)
                ((COMB_FILTER *)(ptr->combs + 2*i+1))->buflen =
                    ((COMB_FILTER *)(ptr->combs + 2*i))->buflen;
            else
                ((COMB_FILTER *)(ptr->combs + 2*i))->buflen =
                    ((COMB_FILTER *)(ptr->combs + 2*i+1))->buflen;
        }
    }

    for (i = 0; i < ptr->num_allps / 2; i++) {
        ((ALLP_FILTER *)(ptr->allps + 2*i))->fb_gain =
            powf(0.001f, 11000.0f * ((ALLP_FILTER *)(ptr->allps + 2*i))->buflen
                 / powf(((ALLP_FILTER *)(ptr->allps + 2*i))->feedback/100.0f, 0.88f)
                 / *(ptr->decay)
                 / ptr->sample_rate);

        ((ALLP_FILTER *)(ptr->allps + 2*i+1))->fb_gain =
            ((ALLP_FILTER *)(ptr->allps + 2*i))->fb_gain;

        ((ALLP_FILTER *)(ptr->allps + 2*i))->in_gain = -0.06f
            / (((ALLP_FILTER *)(ptr->allps + 2 * i))->feedback/100.0f)
            / powf((*(ptr->decay) + 3500.0f) / 10000.0f, 1.5f);

        ((ALLP_FILTER *)(ptr->allps + 2*i+1))->in_gain =
            ((ALLP_FILTER *)(ptr->allps + 2*i))->in_gain;

        if (*(ptr->stereo_enh) > 0.0f) {
            if (i % 2 == 0)
                ((ALLP_FILTER *)(ptr->allps + 2*i+1))->buflen =
                    ENH_STEREO_RATIO * ((ALLP_FILTER *)(ptr->allps + 2*i))->buflen;
            else
                ((ALLP_FILTER *)(ptr->allps + 2*i))->buflen =
                    ENH_STEREO_RATIO * ((ALLP_FILTER *)(ptr->allps + 2*i+1))->buflen;
        } else {
            if (i % 2 == 0)
                ((ALLP_FILTER *)(ptr->allps + 2*i+1))->buflen =
                    ((ALLP_FILTER *)(ptr->allps + 2*i))->buflen;
            else
                ((ALLP_FILTER *)(ptr->allps + 2*i))->buflen =
                    ((ALLP_FILTER *)(ptr->allps + 2*i+1))->buflen;
        }
    }
}


/* Construct a new plugin instance. */
LV2_Handle
instantiate_Reverb(const LV2_Descriptor * Descriptor, double SampleRate, const char* bundle_path, const LV2_Feature* const* features) {

    unsigned long i;
    LV2_Handle * p;
    Reverb * ptr = NULL;

    if ((p = malloc(sizeof(Reverb))) != NULL) {
        ((Reverb *)p)->sample_rate = SampleRate;
        ((Reverb *)p)->smoothdecay =2800.0f;
        ((Reverb *)p)->smoothdry = -4.0f;
        ((Reverb *)p)->smoothwet = -12.0f;

        ptr = (Reverb *)p;

        /* allocate memory for comb/allpass filters and other dynamic vars */
        if ((ptr->combs =
             calloc(2 * MAX_COMBS, sizeof(COMB_FILTER))) == NULL)
            return NULL;
        for (i = 0; i < 2 * MAX_COMBS; i++) {
            if ((((COMB_FILTER *)(ptr->combs + i))->ringbuffer =
                 calloc((unsigned long)MAX_COMB_DELAY * ptr->sample_rate / 1000,
                    sizeof(float))) == NULL)
                return NULL;
            if ((((COMB_FILTER *)(ptr->combs + i))->buffer_pos =
                 calloc(1, sizeof(unsigned long))) == NULL)
                return NULL;
            if ((((COMB_FILTER *)(ptr->combs + i))->filter =
                 calloc(1, sizeof(biquad))) == NULL)
                return NULL;
        }

        if ((ptr->allps =
             calloc(2 * MAX_ALLPS, sizeof(ALLP_FILTER))) == NULL)
            return NULL;
        for (i = 0; i < 2 * MAX_ALLPS; i++) {
            if ((((ALLP_FILTER *)(ptr->allps + i))->ringbuffer =
                 calloc((unsigned long)MAX_ALLP_DELAY * ptr->sample_rate / 1000,
                    sizeof(float))) == NULL)
                return NULL;
            if ((((ALLP_FILTER *)(ptr->allps + i))->buffer_pos =
                 calloc(1, sizeof(unsigned long))) == NULL)
                return NULL;
        }

        if ((ptr->low_pass =
             calloc(2, sizeof(biquad))) == NULL)
            return NULL;
        if ((ptr->high_pass =
             calloc(2, sizeof(biquad))) == NULL)
            return NULL;

        return p;
    }
    return NULL;
}


/* activate a plugin instance */
void
activate_Reverb(LV2_Handle Instance) {

    Reverb * ptr = (Reverb *)Instance;
    unsigned long i,j;

    for (i = 0; i < 2 * MAX_COMBS; i++) {
        for (j = 0; j < (unsigned long)MAX_COMB_DELAY * ptr->sample_rate / 1000; j++)
                ((COMB_FILTER *)(ptr->combs + i))->ringbuffer[j] = 0.0f;
        *(((COMB_FILTER *)(ptr->combs + i))->buffer_pos) = 0;
        ((COMB_FILTER *)(ptr->combs + i))->last_out = 0;
        biquad_init(((COMB_FILTER *)(ptr->combs + i))->filter);
    }

    for (i = 0; i < 2 * MAX_ALLPS; i++) {
        for (j = 0; j < (unsigned long)MAX_ALLP_DELAY * ptr->sample_rate / 1000; j++)
            ((ALLP_FILTER *)(ptr->allps + i))->ringbuffer[j] = 0.0f;
        *(((ALLP_FILTER *)(ptr->allps + i))->buffer_pos) = 0;
        ((ALLP_FILTER *)(ptr->allps + i))->last_out = 0;
    }

    biquad_init(ptr->low_pass);
    biquad_init((biquad *)(ptr->low_pass + 1));
    biquad_init(ptr->high_pass);
    biquad_init((biquad *)(ptr->high_pass + 1));

    ptr->old_decay = -10.0f;
    ptr->old_stereo_enh = -10.0f;
    ptr->old_mode = -10.0f;
}

/* Connect a port to a data location. */
void
connect_port_Reverb(LV2_Handle Instance,
             uint32_t Port,
             void * DataLocation) {

    Reverb * ptr = (Reverb *)Instance;

    switch (Port) {
    case DECAY:
        ptr->decay = (float *) DataLocation;
        break;
    case DRYLEVEL:
        ptr->drylevel = (float *) DataLocation;
        break;
    case WETLEVEL:
        ptr->wetlevel = (float *) DataLocation;
        break;
    case COMBS_EN:
        ptr->combs_en = (float *) DataLocation;
        break;
    case ALLPS_EN:
        ptr->allps_en = (float *) DataLocation;
        break;
    case BANDPASS_EN:
        ptr->bandpass_en = (float *) DataLocation;
        break;
    case STEREO_ENH:
        ptr->stereo_enh = (float *) DataLocation;
        break;
    case MODE:
        ptr->mode = (float *) DataLocation;
        break;
    case INPUT_L:
        ptr->input_L = (float *) DataLocation;
        break;
    case OUTPUT_L:
        ptr->output_L = (float *) DataLocation;
        break;
    case INPUT_R:
        ptr->input_R = (float *) DataLocation;
        break;
    case OUTPUT_R:
        ptr->output_R = (float *) DataLocation;
        break;
    }
}


void
run_Reverb(LV2_Handle Instance,
        uint32_t SampleCount) {

    Reverb * ptr = (Reverb *)Instance;

    unsigned long sample_index;
    int i;

    float calcdecay = (*(ptr->decay)+ptr->smoothdecay)*0.5; //first calculate the smoothed value, then limit it.
    ptr->smoothdecay = calcdecay;
    float decay = LIMIT(calcdecay,0.0f,10000.0f);

    float calcdry = (*(ptr->drylevel)+ptr->smoothdry)*0.5;
    ptr->smoothdry = calcdry;
    float drylevel = db2lin(LIMIT(calcdry,-70.0f,10.0f));

    float calcwet = (*(ptr->wetlevel)+ptr->smoothwet)*0.5;
    ptr->smoothwet = calcwet;
    float wetlevel = db2lin(LIMIT(calcwet,-70.0f,10.0f));


    float combs_en = LIMIT(*(ptr->combs_en),-2.0f,2.0f);
    float allps_en = LIMIT(*(ptr->allps_en),-2.0f,2.0f);
    float bandpass_en = LIMIT(*(ptr->bandpass_en),-2.0f,2.0f);
    float stereo_enh = LIMIT(*(ptr->stereo_enh),-2.0f,2.0f);
    float mode = LIMIT(*(ptr->mode),0,NUM_MODES-1);

    float * input_L = ptr->input_L;
    float * output_L = ptr->output_L;
    float * input_R = ptr->input_R;
    float * output_R = ptr->output_R;

    rev_t out_L = 0;
    rev_t out_R = 0;
    rev_t in_L = 0;
    rev_t in_R = 0;
    rev_t combs_out_L = 0;
    rev_t combs_out_R = 0;


    /* see if the user changed any control since last run */
    if ((ptr->old_decay != decay) ||
        (ptr->old_stereo_enh != stereo_enh) ||
        (ptr->old_mode != mode)) {

        /* re-compute reverberator coefficients */
        comp_coeffs(Instance);

        /* save new values */
        ptr->old_decay = decay;
        ptr->old_stereo_enh = stereo_enh;
        ptr->old_mode = mode;
    }

    for (sample_index = 0; sample_index < SampleCount; sample_index++) {

#ifdef REVERB_CALC_FLOAT
        in_L = *(input_L++);
        in_R = *(input_R++);
#else
        in_L = (sample)((float)F2S * *(input_L++));
        in_R = (sample)((float)F2S * *(input_R++));
#endif

        combs_out_L = in_L;
        combs_out_R = in_R;

        /* process comb filters */
        if (combs_en > 0.0f) {
            for (i = 0; i < ptr->num_combs / 2; i++) {
                combs_out_L +=
                    comb_run(in_L, ((COMB_FILTER *)(ptr->combs + 2*i)));
                combs_out_R +=
                    comb_run(in_R, ((COMB_FILTER *)(ptr->combs + 2*i+1)));
            }
        }

        /* process allpass filters */
        if (allps_en > 0.0f) {
            for (i = 0; i < ptr->num_allps / 2; i++) {
                combs_out_L += allp_run(combs_out_L,
                               ((ALLP_FILTER *)(ptr->allps + 2*i)));
                combs_out_R += allp_run(combs_out_R,
                               ((ALLP_FILTER *)(ptr->allps + 2*i+1)));
            }
        }

        /* process bandpass filters */
        if (bandpass_en > 0.0f) {
            combs_out_L =
                biquad_run(((biquad *)(ptr->low_pass)), combs_out_L);
            combs_out_L =
                biquad_run(((biquad *)(ptr->high_pass)), combs_out_L);
            combs_out_R =
                biquad_run(((biquad *)(ptr->low_pass + 1)), combs_out_R);
            combs_out_R =
                biquad_run(((biquad *)(ptr->high_pass + 1)), combs_out_R);
        }

#ifdef REVERB_CALC_FLOAT
        out_L = in_L * drylevel + combs_out_L * wetlevel;
        out_R = in_R * drylevel + combs_out_R * wetlevel;
        *(output_L++) = out_L;
        *(output_R++) = out_R;
#else
        out_L = (sample)((float)in_L * drylevel + (float)combs_out_L * wetlevel);
        out_R = (sample)((float)in_R * drylevel + (float)combs_out_R * wetlevel);
        *(output_L++) = (float)out_L / (float)F2S;
        *(output_R++) = (float)out_R / (float)F2S;
#endif
    }
}


/* Throw away a Reverb effect instance. */
void
cleanup_Reverb(LV2_Handle Instance) {

    int i;
    Reverb * ptr = (Reverb *)Instance;

    /* free memory allocated for comb/allpass filters & co. in instantiate_Reverb() */
    for (i = 0; i < 2 * MAX_COMBS; i++) {
        free(((COMB_FILTER *)(ptr->combs + i))->ringbuffer);
        free(((COMB_FILTER *)(ptr->combs + i))->buffer_pos);
        free(((COMB_FILTER *)(ptr->combs + i))->filter);
    }
    for (i = 0; i < 2 * MAX_ALLPS; i++) {
        free(((ALLP_FILTER *)(ptr->allps + i))->ringbuffer);
        free(((ALLP_FILTER *)(ptr->allps + i))->buffer_pos);
    }

    free(ptr->combs);
    free(ptr->allps);
    free(ptr->low_pass);
    free(ptr->high_pass);

    free(Instance);

}

const void*
extension_data_Reverb(const char* uri)
{
    return NULL;
}


static const
LV2_Descriptor Descriptor = {
    "http://moddevices.com/plugins/tap/reverb",
    instantiate_Reverb,
    connect_port_Reverb,
    activate_Reverb,
    run_Reverb,
    NULL,
    cleanup_Reverb,
    extension_data_Reverb
};

LV2_SYMBOL_EXPORT
const LV2_Descriptor*
lv2_descriptor(uint32_t index)
{
    if (index == 0) return &Descriptor;
    else return NULL;

}