-#ifndef VG_AUDIO_DSP_H
-#define VG_AUDIO_DSP_H
-
-#define VG_GAME
-#include "vg/vg.h"
+#pragma once
//#define VG_ECHO_LPF_BUTTERWORTH
-static struct vg_dsp{
- float *buffer;
- u32 allocations;
-
- u8 *view_texture_buffer;
- GLuint view_texture;
+#include "vg_platform.h"
+#include "dep/glad/glad.h"
+#include "vg_m.h"
- float echo_distances[14],
- echo_tunings[8],
- reverb_wet_mix,
- reverb_dry_mix;
-
- vg_rand rand;
-}
-vg_dsp;
-
-static float *dsp_allocate( u32 samples )
+struct vg_dsp
{
- samples = vg_align4( samples );
+ float *buffer;
+ u32 allocations;
- if( vg_dsp.allocations + samples > (1024*1024)/4 )
- vg_fatal_error( "too much dsp" );
+ u8 *view_texture_buffer;
+ GLuint view_texture;
- float *buf = &vg_dsp.buffer[ vg_dsp.allocations ];
- vg_dsp.allocations += samples;
+ float echo_distances[14],
+ echo_tunings[8],
+ reverb_wet_mix,
+ reverb_dry_mix;
- return buf;
+ vg_rand rand;
}
-
-
-/*
- * filters
- * ----------------------------------------------
- */
+extern vg_dsp;
struct dsp_delay
{
float gain;
};
-struct dsp_biquad {
+struct dsp_biquad
+{
f32 a0, a1, a2, b1, b2, c0, d0,
xnz1, xnz2, ynz1, ynz2, offset;
};
-static f32 dsp_biquad_process( struct dsp_biquad *bq, f32 xn ){
- f32 yn = + bq->a0*xn + bq->a1*bq->xnz1 + bq->a2*bq->xnz2
- - bq->b1*bq->ynz1 - bq->b2*bq->ynz2;
- bq->xnz2 = bq->xnz1;
- bq->xnz1 = xn;
- bq->ynz2 = bq->ynz1;
- bq->ynz1 = yn;
- return yn + bq->offset;
-}
-
-static void dsp_init_biquad_butterworth_lpf( struct dsp_biquad *bq, f32 fc ){
- f32 c = 1.0f/tanf(VG_PIf*fc / 44100.0f);
- bq->a0 = 1.0f / (1.0f + sqrtf(2.0f)*c + powf(c, 2.0f) );
- bq->a1 = 2.0f * bq->a0;
- bq->a2 = bq->a0;
- bq->b1 = 2.0f * bq->a0*(1.0f - powf(c, 2.0f));
- bq->b2 = bq->a0 * (1.0f - sqrtf(2.0f)*c + powf(c, 2.0f) );
-}
-
-static inline void dsp_read_delay( struct dsp_delay *delay, float *s, u32 t ){
- u32 index = delay->cur+t;
-
- if( index >= delay->length )
- index -= delay->length;
-
- *s = delay->buffer[ index ];
-}
-
-static inline void dsp_write_delay( struct dsp_delay *delay, float *s )
-{
- u32 index = delay->cur;
- delay->buffer[ index ] = *s;
-
- delay->cur ++;
-
- if( delay->cur >= delay->length )
- delay->cur = 0;
-}
-
-static void dsp_init_delay( struct dsp_delay *delay, float length )
-{
- delay->length = 44100.0f * length;
- delay->cur = 0;
- delay->buffer = dsp_allocate( delay->length );
-
- for( int i=0; i<delay->length; i++ )
- delay->buffer[i] = 0.0f;
-}
-
-static void dsp_update_lpf( struct dsp_lpf *lpf, float freq )
-{
- lpf->exponent = 1.0f-expf( -(1.0f/44100.0f) * 2.0f * VG_PIf * freq );
-}
-
-static void dsp_init_lpf( struct dsp_lpf *lpf, float freq )
-{
- lpf->buffer = dsp_allocate( 4 );
- lpf->buffer[0] = 0.0f;
- dsp_update_lpf( lpf, freq );
-}
-
-static inline void dsp_write_lpf( struct dsp_lpf *lpf, float *s )
-{
- float diff = *s - lpf->buffer[0];
- lpf->buffer[0] += diff * lpf->exponent;
-}
-
-static inline void dsp_read_lpf( struct dsp_lpf *lpf, float *s )
-{
- *s = lpf->buffer[0];
-}
-
-static void dsp_init_schroeder( struct dsp_schroeder *sch, float length,
- float gain )
-{
- dsp_init_delay( &sch->M, length );
- sch->gain = gain;
-}
-
-static inline void dsp_process_schroeder( struct dsp_schroeder *sch,
- float *input, float *output )
-{
- float dry = *input;
-
- float delay_output;
- dsp_read_delay( &sch->M, &delay_output, 1 );
-
- float feedback_attenuated = delay_output * sch->gain,
- input_feedback_sum = dry + feedback_attenuated;
-
- dsp_write_delay( &sch->M, &input_feedback_sum );
-
- *output = delay_output - input_feedback_sum*sch->gain;
-}
-
-/* temporary global design */
-static struct dsp_lpf __lpf_mud_free;
-static struct dsp_delay __echos[8];
-
-#ifdef VG_ECHO_LPF_BUTTERWORTH
-static struct dsp_biquad __echos_lpf[8];
-#else
-static struct dsp_lpf __echos_lpf[8];
-#endif
-static struct dsp_schroeder __diffusion_chain[8];
-
-static void async_vg_dsp_alloc_texture( void *payload, u32 size )
-{
- glGenTextures( 1, &vg_dsp.view_texture );
- glBindTexture( GL_TEXTURE_2D, vg_dsp.view_texture );
- glTexImage2D( GL_TEXTURE_2D, 0, GL_RGBA, 256, 256, 0,
- GL_RGBA, GL_UNSIGNED_BYTE, vg_dsp.view_texture_buffer );
- glTexParameteri( GL_TEXTURE_2D, GL_TEXTURE_MIN_FILTER, GL_NEAREST );
- glTexParameteri( GL_TEXTURE_2D, GL_TEXTURE_MAG_FILTER, GL_NEAREST );
-}
-
-static void vg_dsp_init( void ){
- vg_rand_seed( &vg_dsp.rand, 461 );
- vg_dsp.buffer = vg_linear_alloc( vg_mem.rtmemory, 1024*1024*1 );
- vg_dsp.view_texture_buffer = vg_linear_alloc( vg_mem.rtmemory, 512*512 );
-
- vg_async_call( async_vg_dsp_alloc_texture, NULL, 0 );
-
- /* temporary global design */
- dsp_init_lpf( &__lpf_mud_free, 125.0f );
-
- float sizes[] =
- { 2.0f, 4.0f, 8.0f, 16.0f, 32.0f, 64.0f, 128.0f, 256.0f };
-
- float variance = 0.1f;
-
- for( int i=0; i<8; i++ ){
- float reflection_time = ((sizes[i])/343.0f) * 1000.0f;
-
- float var = 1.0f + (vg_randf64(&vg_dsp.rand)*2.0f - 1.0f) * variance,
- total = reflection_time * var;
-
- dsp_init_delay( &__echos[i], total / 1000.0f );
-
- float freq = vg_lerpf( 800.0f, 350.0f, sizes[i] / 256.0f );
-
-#ifdef VG_ECHO_LPF_BUTTERWORTH
- dsp_init_biquad_butterworth_lpf( &__echos_lpf[i], freq );
-#else
- dsp_init_lpf( &__echos_lpf[i], freq );
-#endif
- }
-
- float diffusions[] = { 187.0f, 159.0f, 143.0f, 121.0f,
- 79.0f, 57.0f, 27.0f, 11.0f };
-
- for( int i=0; i<8; i++ ){
- dsp_init_schroeder( __diffusion_chain+i, diffusions[i]/1000.0f, 0.7f );
- }
-}
-
-static void vg_dsp_process( float *stereo_in, float *stereo_out )
-{
- float in_total = (stereo_in[0]+stereo_in[1])*0.5f;
- float recieved = 0.0f;
-
- for( int i=0; i<8; i++ ){
- f32 echo;
- dsp_read_delay( __echos+i, &echo, 1 );
-
-#ifdef VG_ECHO_LPF_BUTTERWORTH
- echo = dsp_biquad_process( __echos_lpf+i, echo );
-#else
- dsp_write_lpf( __echos_lpf+i, &echo );
- dsp_read_lpf( __echos_lpf+i, &echo );
-#endif
-
- recieved += echo * vg_dsp.echo_tunings[i]*0.98;
- }
-
- float diffused = recieved;
-
- for( int i=0; i<8; i++ ){
- dsp_process_schroeder( __diffusion_chain+i, &diffused, &diffused );
- }
-
- float diffuse_mix = vg_dsp.reverb_wet_mix;
- diffuse_mix = vg_lerpf( recieved, diffused, diffuse_mix );
- float total = in_total + diffuse_mix;
-
- float low_mud;
- dsp_write_lpf( &__lpf_mud_free, &total );
- dsp_read_lpf( &__lpf_mud_free, &low_mud );
-
- total -= low_mud;
-
- for( int i=0; i<8; i++ )
- dsp_write_delay( __echos+i, &total );
-
- stereo_out[0] = stereo_in[0]*vg_dsp.reverb_dry_mix;
- stereo_out[1] = stereo_in[1]*vg_dsp.reverb_dry_mix;
- stereo_out[0] += diffuse_mix*2.0f*vg_dsp.reverb_wet_mix;
- stereo_out[1] += diffuse_mix*2.0f*vg_dsp.reverb_wet_mix;
-}
-
-static void dsp_update_tunings(void)
-{
- float sizes[] =
- { 2.0f, 4.0f, 8.0f, 16.0f, 32.0f, 64.0f, 128.0f, 256.0f };
- float volumes[] =
- { 0.2f, 0.3f, 0.5f, 0.7f, 0.8f, 0.9f, 1.0f, 1.0f };
-
- float avg_distance = 0.0f;
-
- for( int i=0; i<8; i++ )
- vg_dsp.echo_tunings[i] = 0.5f;
-
- for( int j=0; j<14; j++ ){
- float d = vg_dsp.echo_distances[j];
-
- for( int i=0; i<7; i++ ){
- if( d < sizes[i+1] ){
- float range = sizes[i+1]-sizes[i];
- float t = vg_clampf( (d - sizes[i])/range, 0.0f, 1.0f );
-
- vg_dsp.echo_tunings[i ] += 1.0f-t;
- vg_dsp.echo_tunings[i+1] += t;
-
- break;
- }
- }
-
- avg_distance += d;
- }
- avg_distance /= 14.0f;
-
-
- vg_dsp.reverb_wet_mix =1.0f-vg_clampf((avg_distance-30.0f)/200.0f,0.0f,1.0f);
- vg_dsp.reverb_dry_mix =1.0f-vg_dsp.reverb_wet_mix*0.4f;
-
- float total = 0.0f;
- for( int i=0; i<8; i++ )
- total += vg_dsp.echo_tunings[i];
-
- if( total > 0.0f ){
- float inverse = 1.0f/total;
-
- for( int i=0;i<8; i++ ){
- vg_dsp.echo_tunings[i] *= inverse;
- }
- }
-
- for( int i=0; i<8; i++ ){
- float freq = vg_lerpf( 200.0f, 500.0f, vg_dsp.echo_tunings[i] );
-
-#ifdef VG_ECHO_LPF_BUTTERWORTH
- dsp_init_biquad_butterworth_lpf( &__echos_lpf[i], freq );
-#else
- dsp_update_lpf( &__echos_lpf[i], freq );
-#endif
- }
-
- for( int i=0;i<8; i++ ){
- vg_dsp.echo_tunings[i] *= volumes[i];
- }
-}
-
-static void vg_dsp_free( void )
-{
- glDeleteTextures( 1, &vg_dsp.view_texture );
-}
-
-static void vg_dsp_update_texture( void )
-{
- for( int i=0; i<512*512; i++ ){
- float v = vg_clampf( vg_dsp.buffer[i] * 0.5f + 0.5f, 0.0f, 1.0f );
- vg_dsp.view_texture_buffer[i] = v * 255.0f;
- }
-}
-
-#endif /* VG_AUDIO_DSP_H */
+void vg_dsp_init( void );
+void vg_dsp_free( void );
+void dsp_update_tunings(void);
+void vg_dsp_process( float *stereo_in, float *stereo_out );
+void vg_dsp_update_texture( void );
+
+f32 dsp_biquad_process( struct dsp_biquad *bq, f32 xn );
+void dsp_init_biquad_butterworth_lpf( struct dsp_biquad *bq, f32 fc );
+void dsp_read_delay( struct dsp_delay *delay, float *s, u32 t );
+void dsp_write_delay( struct dsp_delay *delay, float *s );
+void dsp_init_delay( struct dsp_delay *delay, float length );
+void dsp_update_lpf( struct dsp_lpf *lpf, float freq );
+void dsp_init_lpf( struct dsp_lpf *lpf, float freq );
+void dsp_write_lpf( struct dsp_lpf *lpf, float *s );
+void dsp_read_lpf( struct dsp_lpf *lpf, float *s );
+void dsp_init_schroeder( struct dsp_schroeder *sch, float length, float gain );
+void dsp_process_schroeder( struct dsp_schroeder *sch,
+ float *input, float *output );