Fix adsr at 0 A and add active switch

1 files changed, 72 insertions, 138 deletions

diff --git a/src/synth_engine.c b/src/synth_engine.c
index 57ec29b..41756c7 100644
--- a/src/synth_engine.c
+++ b/src/synth_engine.c
@@ -2,6 +2,23 @@
 #include "lowpass.h"
 #include "filter.h"
 
+/* 1d convolution */
+void
+convole(float *signal, float *filter, size_t signal_size, size_t filter_size, float *out) {
+  for (size_t i = 0; i < filter_size + signal_size; i++) {
+    size_t kmin, kmax, k;
+    out[i] = 0;
+    /* find overlap */
+    kmin = (i >= filter_size - 1) ? i - (filter_size - 1) : 0;
+    kmax = (i < signal_size - 1) ? i : signal_size - 1;
+
+    /* Add the overlaping values */
+    for (k = kmin; k <= kmax; k++) {
+      out[i] += signal[k] * filter[i - k];
+    }
+  }
+}
+
 float
 adsr_amplitude(void *synthData, unsigned long long elapsed)
 {
@@ -14,20 +31,20 @@ adsr_amplitude(void *synthData, unsigned long long elapsed)
   float dLifeTime = (elapsed * (1.0 / (float)SAMPLE_RATE));
 
   if (synth->n.noteOn != 0 && synth->n.noteOff == 0) {
-    if (dLifeTime <= synth->adsr.a)
+    if (dLifeTime < synth->adsr.a)
       dAmplitude = (dLifeTime / synth->adsr.a)*(dLifeTime / synth->adsr.a) * dStartAmplitude;
 
-    if (dLifeTime >  synth->adsr.a && dLifeTime <= ( synth->adsr.a +  synth->adsr.d))
+    if (dLifeTime >=  synth->adsr.a && dLifeTime <= ( synth->adsr.a +  synth->adsr.d))
       dAmplitude = ((dLifeTime - synth->adsr.a) / synth->adsr.d) * (synth->adsr.s - dStartAmplitude) + dStartAmplitude;
 
     if (dLifeTime > (synth->adsr.a + synth->adsr.d))
       dAmplitude = synth->adsr.s;
   }
   else { // Note is off
-    if (dLifeTime <= synth->adsr.a)
+    if (dLifeTime < synth->adsr.a)
       dReleaseAmplitude = (dLifeTime / synth->adsr.a)*(dLifeTime / synth->adsr.a) * dStartAmplitude;
 
-    if (dLifeTime > synth->adsr.a && dLifeTime <= (synth->adsr.a + synth->adsr.d))
+    if (dLifeTime >= synth->adsr.a && dLifeTime <= (synth->adsr.a + synth->adsr.d))
       dReleaseAmplitude = ((dLifeTime - synth->adsr.a) / synth->adsr.d) * (synth->adsr.s - dStartAmplitude) + dStartAmplitude;
 
     if (dLifeTime > (synth->adsr.a + synth->adsr.d))
@@ -38,7 +55,7 @@ adsr_amplitude(void *synthData, unsigned long long elapsed)
     if (synth->adsr.r < 0) {
       dAmplitude = synth->adsr.s;
     }
-}
+  }
   // Amplitude should not be negative
   if (dAmplitude <= 0.000)
     dAmplitude = 0.0;
@@ -118,91 +135,45 @@ gen3(float f, unsigned long long phase, float x, unsigned int sample_rate)
   /*   + sqr_sample(0.2, f * x, 0.2 * x * x, phase, sample_rate); */
 }
 
-
-
-/* 1d convolution */
-void
-convole(float *signal, float *filter, size_t signal_size, size_t filter_size, float *out) {
-  for (size_t i = 0; i < filter_size + signal_size; i++) {
-    size_t kmin, kmax, k;
-    out[i] = 0;
-    /* find overlap */
-    kmin = (i >= filter_size - 1) ? i - (filter_size - 1) : 0;
-    kmax = (i < signal_size - 1) ? i : signal_size - 1;
-
-    /* Add the overlaping values */
-    for (k = kmin; k <= kmax; k++) {
-      out[i] += signal[k] * filter[i - k];
-    }
-  }
-}
-
-void
-low_pass_filter(float* signal, int length, float cutoff, float resonance, float* out) {
-    float c = 1.0f / tanf(M_PI * cutoff); // calculate filter constant
-    float a1 = 1.0f / (1.0f + resonance * c + c * c); // calculate filter coefficients
-    float a2 = 2.0f * a1;
-    float a3 = a1;
-    float b1 = 2.0f * (1.0f - c * c) * a1;
-    float b2 = (1.0f - resonance * c + c * c) * a1;
-    float prev_input = 0.0f, prev_output = 0.0f; // initialize previous input and output to zero
-    for (int i = 0; i < length; i++) {
-        float input = signal[i];
-        float output = a1 * input + a2 * prev_input + a3 * prev_output - (i >= 1 ? b1 * out[i-1] : 0.0f) - (i >= 2 ? b2 * out[i-2] : 0.0f);
-        out[i] = output;
-        prev_input = input;
-        prev_output = output;
-    }
+float
+clamp(float f)
+{
+  if (f <= -1) return -0.9999;
+  if (f >= 1)  return  0.9999;
 }
 
-
 float
 make_sample(unsigned long long phase, void *synthData, unsigned int sample_rate, int viz)
 {
   synth_t *synth = (synth_t*)synthData;
   float sample = 0;
 
-
+  //LFO!
+  //if (synth->adsr.elapsed > SAMPLE_RATE / 2) synth->adsr.elapsed = 0;
+    
   int n = 1;
-  if (1 /* !synth->filter */) {
-    for (int i = 0; i < n; i++) {
-      sample += (1.0 / n) * synth->gen[synth->geni](synth->n.freq + synth->freq_offset, phase, synth->x, sample_rate);
-    }
-
-    if (!viz && synth->filter) {
-      // ALLL THE FILTERS
-      LowPass_Update(synth->resonance, (adsr_amplitude(synth, synth->adsr.elapsed) + 0.1) * synth->cutoff + 1, sample_rate);
-      sample = LowPass_Filter(sample);
+  for (int i = 0; i < n; i++) {
+    sample += (1.0 / n) * synth->gen[synth->geni](synth->n.freq + synth->freq_offset, phase, synth->x, sample_rate);
+  }
 
-      update_bw_low_pass_filter(synth->fff, SAMPLE_RATE, (adsr_amplitude(synth, synth->adsr.elapsed) + 0.1) * synth->cutoff, synth->resonance);
-      sample = bw_low_pass(synth->fff, sample);
-    }
+  if (!viz && synth->filter) {
+    // ALLL THE FILTERS
+    LowPass_Update(synth->resonance, (adsr_amplitude(synth, synth->adsr.elapsed) + 0.1) * round(synth->cutoff) + 1, sample_rate);
+    sample = LowPass_Filter(sample);
 
-    sample = synth->gain * adsr_amplitude(synth, synth->adsr.elapsed) *
-      sample; //synth->gen[synth->geni](synth->n.freq + synth->freq_offset, phase, synth->x);
-    
-    if (synth->clamp && sample >= 1) sample = 0.99;
-    if (synth->clamp && sample <= -1) sample = -0.99;
-  } else {
-    // get sample array s[]
-    int samples = 30;
-    float s[samples];
-    
-    if (synth->adsr.elapsed < samples) {
-      for (int i = 0; i < samples; i++) {
-        s[i] = synth->gain * adsr_amplitude(synth, i) * synth->gen[synth->geni](synth->n.freq + synth->freq_offset, i, synth->x, sample_rate);
-      }
-    } else {
-      for (int i = 0; i < samples; i++) {
-        s[i] = synth->gain * adsr_amplitude(synth, synth->adsr.elapsed - 50 + i) * synth->gen[synth->geni](synth->n.freq + synth->freq_offset, phase - 50 + i, synth->x, sample_rate);
-      }
-    }
+    update_bw_low_pass_filter(synth->fff, SAMPLE_RATE, (adsr_amplitude(synth, synth->adsr.elapsed) + 0.1) * synth->cutoff, synth->resonance);
+    sample = bw_low_pass(synth->fff, sample);
+  }
 
-    // process s[]
+  sample = synth->gain * adsr_amplitude(synth, synth->adsr.elapsed) * sample;
 
+    
+  // band stop for high freqs
+  if (!viz)
+    sample = bw_band_stop(synth->fff2, sample);
 
-    // return s[50]
-  }
+  
+  if (synth->clamp) sample = clamp(sample);
   
   return sample;
 }
@@ -221,70 +192,30 @@ sound_gen(const void *inputBuffer, void *outputBuffer,
   (void) statusFlags;
   (void) inputBuffer;
 
-  if (1) {
-    float s;
-    for( unsigned long i=0; i<framesPerBuffer; i++ ) {
-      //get_portaudio_frame(outputBuffer, synth);
-      s = make_sample(synth->n.elapsed, synth, SAMPLE_RATE, 0);
-      *out++ = s;
-      *out++ = s;
-      synth->adsr.elapsed++;
-      synth->n.elapsed++;
-      if (!synth->multi) {
-        if (synth->n.elapsed >= (1.0 / synth->n.freq) * SAMPLE_RATE) synth->n.elapsed = 0;
-      } else {
-      
-      }
-    }
-  } else {
-    float s[FRAMES_PER_BUFFER * 5];
-
-    if (synth->adsr.elapsed < framesPerBuffer * 5) {
-      for (unsigned long long i = 0; i < framesPerBuffer * 5; i++) {
-        s[i] = make_sample(i, synth, SAMPLE_RATE, 0);
-        synth->adsr.elapsed++;
-        synth->n.elapsed++;
-        if (!synth->multi) {
-          if (synth->n.elapsed >= (1.0 / synth->n.freq) * SAMPLE_RATE) synth->n.elapsed = 0;
-        } else {
-        }
-      }
-    } else {
-      for (unsigned long long i = 0; i < framesPerBuffer * 5; i++) {
-        s[i] = make_sample(synth->n.elapsed - framesPerBuffer * 2 + i, synth, SAMPLE_RATE, 0);
-        synth->adsr.elapsed++;
-        synth->n.elapsed++;
-        if (!synth->multi) {
-          if (synth->n.elapsed >= (1.0 / synth->n.freq) * SAMPLE_RATE) synth->n.elapsed = 0;
-        } else {
-        }
-      }
+  float s;
+  for( unsigned long i=0; i<framesPerBuffer; i++ ) {
+    //get_portaudio_frame(outputBuffer, synth);
+    if (!synth->active) {
+      *out++ = 0.0f;
+      *out++ = 0.0f;
+      continue;
     }
-
-    // filter
-
-    // output
-
-    if (synth->adsr.elapsed < framesPerBuffer * 5) {
-      for( unsigned long i=0; i<framesPerBuffer; i++ ) {
-        *out++ = s[i];
-        *out++ = s[i];
-      }
-    } else {
-      for( unsigned long i=0; i<framesPerBuffer; i++ ) {
-        *out++ = s[i + (2 * framesPerBuffer)];
-        *out++ = s[i + (2 * framesPerBuffer)];
-      }
+    if (adsr_amplitude(synth, synth->adsr.elapsed) == 0 && synth->n.noteOff != 0) {
+      printf("SYNTH OPFF\n");
+      synth->active = 0;
+      *out++ = 0.0f;
+      *out++ = 0.0f;
+      continue;
     }
-    synth->adsr.elapsed-= 4*framesPerBuffer;
-
+    s = make_sample(synth->n.elapsed, synth, SAMPLE_RATE, 0);
+    *out++ = s;
+    *out++ = s;
+    synth->adsr.elapsed++;
+    synth->n.elapsed++;
     if (!synth->multi) {
-      for (int i = 0; i < framesPerBuffer * 4; i++) {
-        synth->n.elapsed--;
-        if (synth->n.elapsed == 0) synth->n.elapsed = (int)(SAMPLE_RATE / synth->n.freq);
-      }
+      if (synth->n.elapsed >= (1.0 / synth->n.freq) * SAMPLE_RATE) synth->n.elapsed = 0;
     } else {
-      synth->n.elapsed-= 4*framesPerBuffer;
+      
     }
   }
 
@@ -305,7 +236,7 @@ init_synth(synth_t * synth)
   synth->n.elapsed = 0; 
 
 
-  synth->adsr.a = 0.001;
+  synth->adsr.a = 0.0;
   synth->adsr.d = 0.3;
   synth->adsr.s = 0.7;
   synth->adsr.r = 0.4;
@@ -317,7 +248,7 @@ init_synth(synth_t * synth)
   synth->filter = 0;
   synth->cutoff = 22000.0f;
   synth->resonance = 1.0f;
-  synth->clamp = 0;
+  synth->clamp = 1;
 
   synth->gen[0] = gen0;
   synth->gen[1] = gen1;
@@ -325,8 +256,11 @@ init_synth(synth_t * synth)
   synth->gen[3] = gen3;
   synth->geni = 0;
 
+  synth->active = 0;
+  
   synth->viz.sample_rate_divider = 1;
 
   LowPass_Init();
   synth->fff = create_bw_low_pass_filter(2, SAMPLE_RATE, 400);
+  synth->fff2 = create_bw_band_stop_filter(8, SAMPLE_RATE, 15000, 22000);
 }