SDL for audio conversion

Makefile

@@ -12,7 +12,7 @@ UNAME_P != uname -m
 CCACHE = #ccache
 
 #CC specifies which compiler we're using
-CC = $(CCACHE) tcc
+CC = $(CCACHE) tcc -DSDL_DISABLE_IMMINTRIN_H
 
 MUSL = /usr/local/musl/include
 
@@ -97,7 +97,7 @@ ifeq ($(UNAME), Windows_NT)
 	EXT = .exe
 else
 	LINKER_FLAGS = -g /usr/lib64/pipewire-0.3/jack/libjack.so.0 #/usr/local/lib/tcc/bcheck.o /usr/local/lib/tcc/bt-exe.o /usr/local/lib/tcc/bt-log.o
-	ELIBS = m c engine editor glfw3 portaudio rt asound pthread
+	ELIBS = m c engine editor glfw3 portaudio rt asound pthread SDL2
 	CLIBS =
 	EXT =
 endif

source/engine/circbuf.c

@@ -1,10 +1,12 @@
 #include "circbuf.h"
 
+#include "util.h"
 #include "assert.h"
 
-struct circbuf circbuf_init(size_t size, int len)
+struct circbuf circbuf_init(size_t size, unsigned int len)
 {
     struct circbuf new;
+    new.len = powof2(len);
     new.len = len;
     new.data = calloc(sizeof(short), new.len);
     new.read = new.write = 0;

source/engine/circbuf.h

@@ -8,10 +8,10 @@ struct circbuf {
     int16_t *data;
     uint32_t read;
     uint32_t write;
-    int len;
+    unsigned int len;
 };
 
-struct circbuf circbuf_init(size_t size, int len);
+struct circbuf circbuf_init(size_t size, unsigned int len);
 void cbuf_push(struct circbuf *buf, short data);
 short cbuf_shift(struct circbuf *buf);
 

source/engine/dsp.c

@@ -73,10 +73,12 @@ struct wav gen_triangle(float amp, float freq, int sr, int ch)
     if (amp > 1) amp = 1;
     if (amp < 0) amp = 0;
 
+    short *data = (short*)new.data;
+
     for (int i = 0; i < new.frames; i++) {
         short val = 2 * abs( (i/new.frames) - floor( (i/new.frames) + 0.5));
         for (int j = 0; j < new.ch; j++) {
-            new.data[i+j] = val;
+            data[i+j] = val;
         }
     }
 }
@@ -88,12 +90,24 @@ struct wav gen_saw(float amp, float freq, int sr, int ch)
     if (amp > 1) amp = 1;
     if (amp < 0) amp = 0;
 
-    samp = amp*SHRT_MAX;
+    short samp = amp*SHRT_MAX;
+
+    short *data = (short*)new.data;
 
     for (int i = 0; i < new.frames; i++) {
         short val = samp * 2 * i/sr - samp;
         for (int j = 0; j < new.ch; j++) {
-            new.data[i+j] = val;
+            data[i+j] = val;
         }
     }
 }
+
+void make_dsp_filter()
+{
+
+}
+
+void dsp_filter(short *in, short *out, int samples, struct dsp_delay *d)
+{
+
+}

source/engine/dsp.h

@@ -1,12 +1,25 @@
 #ifndef DSP_H
 #define DSP_H
 
+#include "circbuf.h"
+
 void am_mod(short *a, short *b, short *c, int n);
 
+struct dsp_filter {
+    void (*filter)(short *in, short *out, int samples, void *data);
+    void *data;
+};
+
+struct dsp_delay {
+    unsigned int ms_delay;
+    struct circbuf buf;
+};
+
 struct wav;
 
 struct wav gen_sine(float amp, float freq, int sr, int ch);
 struct wav gen_square(float amp, float freq, int sr, int ch);
 struct wav gen_triangle(float amp, float freq, int sr, int ch);
+struct wav gen_saw(float amp, float freq, int sr, int ch);
 
 #endif

source/engine/sound.c

@@ -7,8 +7,14 @@
 #include "limits.h"
 #include "time.h"
 
+
+#include "SDL2/SDL.h"
+
 #include "dsp.h"
 
+#define TSF_IMPLEMENTATION
+#include "tsf.h"
+
 
 #define DR_WAV_IMPLEMENTATION
 #include "dr_wav.h"
@@ -37,6 +43,58 @@ struct sound wavsound;
 
 int vidplaying = 0;
 
+struct wav change_samplerate(struct wav w, int rate)
+{
+    SDL_AudioCVT cvt;
+    printf("Convert from %i to %i.\n", w.samplerate, rate);
+
+    SDL_BuildAudioCVT(&cvt, AUDIO_S16, w.ch, w.samplerate, AUDIO_S16, w.ch, rate);
+
+    cvt.len = w.frames * w.ch * sizeof(short);
+    cvt.buf = malloc(cvt.len * cvt.len_mult);
+    memcpy(cvt.buf, w.data, cvt.len*cvt.len_mult);
+    SDL_ConvertAudio(&cvt);
+
+   w.samplerate = rate;
+   free(w.data);
+   w.data = cvt.buf;
+   printf("cvt len: %i\n", cvt.len_cvt);
+   w.frames = cvt.len_cvt / (w.ch * sizeof(short));
+
+
+/*
+    float change = (float)rate/w.samplerate;
+    int oldsamples = w.frames * w.ch;
+    w.samplerate = rate;
+    w.frames *= change;
+
+    short *old = (short*)w.data;
+    short *new = calloc(w.frames * w.ch, sizeof(short));
+
+    int samples =  w.frames*w.ch;
+
+    short s1;
+    short s2;
+
+    for (int i = 0; i < w.frames; i++) {
+        for (int j = 0; j < w.ch; j++) {
+            int v1 = ((float)(i*w.ch+j)/samples) * oldsamples;
+            int v2 = ((float)(i*w.ch+j+w.ch)/samples) * oldsamples;
+            printf("Val is %i and %i.\n", v1, v2);
+            s1 = old[v1];
+            s2 = old[v2];
+            new[i*w.ch+j] = (s1 + s2) >> 1; // Average of the two with bitshift ops
+        }
+    }
+
+    printf("Old samples: %i\nNew samples: %i\nFrames:%i\n", oldsamples, samples, w.frames);
+
+    w.data = new;
+
+    free(old);
+    */
+}
+
 static int patestCallback(const void *inputBuffer, void *outputBuffer, unsigned long framesPerBuffer, const PaStreamCallbackTimeInfo *timeInfo, PaStreamCallbackFlags statusFlags, void *userData)
 {
     /* Cast data passed through stream to our structure. */
@@ -59,7 +117,6 @@ static int patestCallback(const void *inputBuffer, void *outputBuffer, unsigned
         //wavsound.data->gain = -6;
 
         float mult = powf(10.f, (float)wavsound.data->gain/20.f);
-        printf("Mult is %f\n", mult);
         short *s = (short*)wavsound.data->data;
         for (int i = 0; i < framesPerBuffer; i++) {
             out[i*2] = s[wavsound.frame++] * mult;
@@ -135,16 +192,9 @@ void sound_init()
 
     printf("Loaded wav: ch %i, sr %i, fr %i.\n", mwav.ch, mwav.samplerate, mwav.frames);
 
-    mwav = gen_square(1, 150, 48000, 2);
+    change_samplerate(mwav, 48000);
 
-/*
+    //mwav = gen_square(1, 150, 48000, 2);
-    short *tdata = mwav.data;
-    mwav.frames /= 2;
-    short *newdata = calloc(mwav.frames * 2, sizeof(short));
-    for (int i = 0; i < mwav.frames; i++) {
-        newdata[i] = tdata[i*2];
-    }
-*/
 
     wavsound.data = &mwav;
     wavsound.loop = 1;

source/engine/sound.h

@@ -18,7 +18,7 @@ enum MUS {
 struct sound {
     int sound;
     int loop;
-    int ch;
+    unsigned int ch;
     int fin;
     int frame;
     int play;
@@ -28,9 +28,9 @@ struct sound {
 };
 
 struct wav {
-    int ch;
+    unsigned int ch;
-    int samplerate;
+    unsigned int samplerate;
-    int frames;
+    unsigned int frames;
     double gain;
     void *data;
 };

source/engine/texture.c

@@ -6,6 +6,7 @@
 #include <stb_ds.h>
 #include "log.h"
 #include <math.h>
+#include "util.h"
 
 static struct {
     char *key;
@@ -167,25 +168,7 @@ void tex_anim_calc_uv(struct TexAnimation *anim)
     anim->uv = uv;
 }
 
-unsigned int powof2(unsigned int num)
-{
-    if (num != 0) {
-	num--;
-	num |= (num >> 1);
-	num |= (num >> 2);
-	num |= (num >> 4);
-	num |= (num >> 8);
-	num |= (num >> 16);
-	num++;
-    }
 
-    return num;
-}
-
-int ispow2(int num)
-{
-    return (num && !(num & (num - 1)));
-}
 
 void tex_bind(struct Texture *tex)
 {