mirror of
https://github.com/godotengine/godot.git
synced 2024-12-29 06:13:24 +00:00
240 lines
6.1 KiB
C++
240 lines
6.1 KiB
C++
/*************************************************************************/
|
|
/* eq.cpp */
|
|
/*************************************************************************/
|
|
/* This file is part of: */
|
|
/* GODOT ENGINE */
|
|
/* http://www.godotengine.org */
|
|
/*************************************************************************/
|
|
/* Copyright (c) 2007-2017 Juan Linietsky, Ariel Manzur. */
|
|
/* */
|
|
/* Permission is hereby granted, free of charge, to any person obtaining */
|
|
/* a copy of this software and associated documentation files (the */
|
|
/* "Software"), to deal in the Software without restriction, including */
|
|
/* without limitation the rights to use, copy, modify, merge, publish, */
|
|
/* distribute, sublicense, and/or sell copies of the Software, and to */
|
|
/* permit persons to whom the Software is furnished to do so, subject to */
|
|
/* the following conditions: */
|
|
/* */
|
|
/* The above copyright notice and this permission notice shall be */
|
|
/* included in all copies or substantial portions of the Software. */
|
|
/* */
|
|
/* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, */
|
|
/* EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF */
|
|
/* MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.*/
|
|
/* IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY */
|
|
/* CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, */
|
|
/* TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE */
|
|
/* SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE. */
|
|
/*************************************************************************/
|
|
|
|
// Author: reduzio@gmail.com (C) 2006
|
|
|
|
#include "eq.h"
|
|
#include <math.h>
|
|
#include "error_macros.h"
|
|
#include "math_funcs.h"
|
|
|
|
#define POW2(v) ((v)*(v))
|
|
|
|
/* Helper */
|
|
static int solve_quadratic(double a,double b,double c,double *r1, double *r2) {
|
|
//solves quadractic and returns number of roots
|
|
|
|
double base=2*a;
|
|
if (base == 0.0f)
|
|
return 0;
|
|
|
|
double squared=b*b-4*a*c;
|
|
if (squared<0.0)
|
|
return 0;
|
|
|
|
squared=sqrt(squared);
|
|
|
|
*r1=(-b+squared)/base;
|
|
*r2=(-b-squared)/base;
|
|
|
|
if (*r1==*r2)
|
|
return 1;
|
|
else
|
|
return 2;
|
|
}
|
|
|
|
EQ::BandProcess::BandProcess() {
|
|
|
|
c1=c2=c3=history.a1=history.a2=history.a3=0;
|
|
history.b1=history.b2=history.b3=0;
|
|
}
|
|
|
|
void EQ::recalculate_band_coefficients() {
|
|
|
|
#define BAND_LOG( m_f ) ( log((m_f)) / log(2.) )
|
|
|
|
for (int i=0;i<band.size();i++) {
|
|
|
|
double octave_size;
|
|
|
|
double frq=band[i].freq;
|
|
|
|
if (i==0) {
|
|
|
|
octave_size=BAND_LOG(band[1].freq)-BAND_LOG(frq);
|
|
} else if (i==(band.size()-1)) {
|
|
|
|
octave_size=BAND_LOG(frq)-BAND_LOG(band[i-1].freq);
|
|
} else {
|
|
|
|
double next=BAND_LOG(band[i+1].freq)-BAND_LOG(frq);
|
|
double prev=BAND_LOG(frq)-BAND_LOG(band[i-1].freq);
|
|
octave_size=(next+prev)/2.0;
|
|
}
|
|
|
|
|
|
|
|
double frq_l=round(frq/pow(2.0,octave_size/2.0));
|
|
|
|
|
|
|
|
double side_gain2=POW2(Math_SQRT12);
|
|
double th=2.0*Math_PI*frq/mix_rate;
|
|
double th_l=2.0*Math_PI*frq_l/mix_rate;
|
|
|
|
double c2a=side_gain2 * POW2(cos(th))
|
|
- 2.0 * side_gain2 * cos(th_l) * cos(th)
|
|
+ side_gain2
|
|
- POW2(sin(th_l));
|
|
|
|
double c2b=2.0 * side_gain2 * POW2(cos(th_l))
|
|
+ side_gain2 * POW2(cos(th))
|
|
- 2.0 * side_gain2 * cos(th_l) * cos(th)
|
|
- side_gain2
|
|
+ POW2(sin(th_l));
|
|
|
|
double c2c=0.25 * side_gain2 * POW2(cos(th))
|
|
- 0.5 * side_gain2 * cos(th_l) * cos(th)
|
|
+ 0.25 * side_gain2
|
|
- 0.25 * POW2(sin(th_l));
|
|
|
|
//printf("band %i, precoefs = %f,%f,%f\n",i,c2a,c2b,c2c);
|
|
|
|
double r1,r2; //roots
|
|
int roots=solve_quadratic(c2a,c2b,c2c,&r1,&r2);
|
|
|
|
ERR_CONTINUE( roots==0 );
|
|
|
|
band[i].c1=2.0 * ((0.5-r1)/2.0);
|
|
band[i].c2=2.0 * r1;
|
|
band[i].c3=2.0 * (0.5+r1) * cos(th);
|
|
//printf("band %i, coefs = %f,%f,%f\n",i,(float)bands[i].c1,(float)bands[i].c2,(float)bands[i].c3);
|
|
|
|
}
|
|
}
|
|
|
|
void EQ::set_preset_band_mode(Preset p_preset) {
|
|
|
|
|
|
band.clear();
|
|
|
|
#define PUSH_BANDS(m_bands) \
|
|
for (int i=0;i<m_bands;i++) { \
|
|
Band b; \
|
|
b.freq=bands[i];\
|
|
band.push_back(b);\
|
|
}
|
|
|
|
switch (p_preset) {
|
|
|
|
case PRESET_6_BANDS: {
|
|
|
|
static const double bands[] = { 32 , 100 , 320 , 1e3, 3200, 10e3 };
|
|
PUSH_BANDS(6);
|
|
|
|
} break;
|
|
|
|
case PRESET_8_BANDS: {
|
|
|
|
static const double bands[] = { 32,72,192,512,1200,3000,7500,16e3 };
|
|
|
|
PUSH_BANDS(8);
|
|
} break;
|
|
|
|
case PRESET_10_BANDS: {
|
|
static const double bands[] = { 31.25, 62.5, 125 , 250 , 500 , 1e3, 2e3, 4e3, 8e3, 16e3 };
|
|
|
|
PUSH_BANDS(10);
|
|
|
|
} break;
|
|
|
|
case PRESET_21_BANDS: {
|
|
|
|
static const double bands[] = { 22 , 32 , 44 , 63 , 90 , 125 , 175 , 250 , 350 , 500 , 700 , 1e3, 1400 , 2e3, 2800 , 4e3, 5600 , 8e3, 11e3, 16e3, 22e3 };
|
|
PUSH_BANDS(21);
|
|
|
|
} break;
|
|
|
|
case PRESET_31_BANDS: {
|
|
|
|
static const double bands[] = { 20, 25, 31.5, 40 , 50 , 63 , 80 , 100 , 125 , 160 , 200 , 250 , 315 , 400 , 500 , 630 , 800 , 1e3 , 1250 , 1600 , 2e3, 2500 , 3150 , 4e3, 5e3, 6300 , 8e3, 10e3, 12500 , 16e3, 20e3 };
|
|
PUSH_BANDS(31);
|
|
} break;
|
|
|
|
};
|
|
|
|
recalculate_band_coefficients();
|
|
}
|
|
|
|
int EQ::get_band_count() const {
|
|
|
|
return band.size();
|
|
}
|
|
float EQ::get_band_frequency(int p_band) {
|
|
|
|
ERR_FAIL_INDEX_V(p_band,band.size(),0);
|
|
return band[p_band].freq;
|
|
}
|
|
void EQ::set_bands(const Vector<float>& p_bands) {
|
|
|
|
band.resize(p_bands.size());
|
|
for (int i=0;i<p_bands.size();i++) {
|
|
|
|
band[i].freq=p_bands[i];
|
|
}
|
|
|
|
recalculate_band_coefficients();
|
|
|
|
}
|
|
|
|
void EQ::set_mix_rate(float p_mix_rate) {
|
|
|
|
mix_rate=p_mix_rate;
|
|
recalculate_band_coefficients();
|
|
}
|
|
|
|
EQ::BandProcess EQ::get_band_processor(int p_band) const {
|
|
|
|
|
|
EQ::BandProcess band_proc;
|
|
|
|
ERR_FAIL_INDEX_V(p_band,band.size(),band_proc);
|
|
|
|
band_proc.c1=band[p_band].c1;
|
|
band_proc.c2=band[p_band].c2;
|
|
band_proc.c3=band[p_band].c3;
|
|
|
|
return band_proc;
|
|
|
|
|
|
}
|
|
|
|
|
|
EQ::EQ()
|
|
{
|
|
mix_rate=44100;
|
|
}
|
|
|
|
|
|
EQ::~EQ()
|
|
{
|
|
}
|
|
|
|
|