Change granular public API to beginFreeze(), beginPitchShift(), stop()

effect_granular.cpp

@@ -38,46 +38,34 @@ void AudioEffectGranular::begin(int16_t *sample_bank_def, int16_t max_len_def)
 	sample_bank = sample_bank_def;
 }
 
-void AudioEffectGranular::freeze(int16_t activate, int16_t playpack_rate_def, int16_t freeze_length_def)
+void AudioEffectGranular::beginFreeze_int(int grain_samples)
 {
-	if (activate == 0) {
-		grain_mode = 0;
-		allow_len_change = true;
-		return;
-	}
 	__disable_irq();
 	grain_mode = 1;
-	rate(playpack_rate_def);
-	if (max_sample_len <= 1500) {
-		freeze_len = max_sample_len;
+	if (grain_samples < max_sample_len) {
+		freeze_len = grain_samples;
 	} else {
-		freeze_len = ((max_sample_len - 1500) * freeze_length_def / 1023) + 1500;
+		freeze_len = grain_samples;
 	}
 	sample_loaded = false;
 	write_en = false;
 	sample_req = true;
 	__enable_irq();
 	Serial.print("in = ");
-	Serial.print(freeze_length_def);
+	Serial.print(grain_samples);
 	Serial.print(", freeze len = ");
 	Serial.println(freeze_len);
 }
 
-void AudioEffectGranular::shift(int16_t activate, int16_t playpack_rate_def, int16_t grain_length_def)
+void AudioEffectGranular::beginPitchShift_int(int grain_samples)
 {
-	if (activate == 0) {
-		grain_mode = 0;
-		allow_len_change = true;
-		return;
-	}
 	__disable_irq();
 	grain_mode = 2;
-	rate(playpack_rate_def);
 	if (allow_len_change) {
-		if (grain_length_def < 100) grain_length_def = 100;
+		if (grain_samples < 100) grain_samples = 100;
 		int maximum = (max_sample_len - 1) / 3;
-		if (grain_length_def > maximum) grain_length_def = maximum;
-		glitch_len = grain_length_def;
+		if (grain_samples > maximum) grain_samples = maximum;
+		glitch_len = grain_samples;
 	}
 	sample_loaded = false;
 	write_en = false;
@@ -85,6 +73,12 @@ void AudioEffectGranular::shift(int16_t activate, int16_t playpack_rate_def, int
 	__enable_irq();
 }
 
+void AudioEffectGranular::stop()
+{
+	grain_mode = 0;
+	allow_len_change = true;
+}
+
 void AudioEffectGranular::rate(int16_t playpack_rate_def)
 {
 	playpack_rate = playpack_rate_def;

effect_granular.h

@@ -29,10 +29,19 @@ public:
 	AudioEffectGranular(void): AudioStream(1,inputQueueArray) { }
 	void begin(int16_t *sample_bank_def, int16_t max_len_def);
 	void rate(int16_t playpack_rate_def);
-	void freeze(int16_t activate, int16_t playpack_rate_def, int16_t grain_length_def);
-	void shift(int16_t activate, int16_t playpack_rate_def, int16_t grain_length_def);
+	void beginFreeze(float grain_length) {
+		if (grain_length <= 0.0) return;
+		beginFreeze_int(grain_length * (AUDIO_SAMPLE_RATE_EXACT * 0.001) + 0.5);
+	}
+	void beginPitchShift(float grain_length) {
+		if (grain_length <= 0.0) return;
+		beginPitchShift_int(grain_length * (AUDIO_SAMPLE_RATE_EXACT * 0.001) + 0.5);
+	}
+	void stop();
 	virtual void update(void);
 private:
+	void beginFreeze_int(int grain_samples);
+	void beginPitchShift_int(int grain_samples);
 	audio_block_t *inputQueueArray[1];
 	int16_t *sample_bank;
 	int16_t max_sample_len;

examples/Effects/Granular/Granular.ino

@@ -20,7 +20,7 @@ Bounce button0 = Bounce(0, 15);
 Bounce button1 = Bounce(1, 15);
 Bounce button2 = Bounce(2, 15);
 
-#define GRANULAR_MEMORY_SIZE 12800  // enough for 29 ms at 44.1 kHz
+#define GRANULAR_MEMORY_SIZE 12800  // enough for 290 ms at 44.1 kHz
 int16_t granularMemory[GRANULAR_MEMORY_SIZE];
 
 // Use these with the Teensy Audio Shield
@@ -87,22 +87,26 @@ void loop() {
   button0.update();
   button1.update();
   button2.update();
-  // read knobs
-  int knobA2 = analogRead(A2);
-  int knobA3 = analogRead(A3);
+  // read knobs, scale to 0-1.0 numbers
+  float knobA2 = (float)analogRead(A2) / 1023.0;
+  float knobA3 = (float)analogRead(A3) / 1023.0;
 
   if (button0.fallingEdge()) {
-    granular1.freeze(1, knobA2, knobA3);
+    // Button 0 starts Freeze effect
+    granular1.beginFreeze(knobA3 * 290.0);
   }
   if (button0.risingEdge()) {
-    granular1.freeze(0, knobA2, knobA3);
+    granular1.stop();
   }
 
   if (button1.fallingEdge()) {
-    granular1.shift(1, knobA2, knobA3);
+    // Button 1 starts Pitch Shift effect
+    granular1.beginPitchShift(knobA3 * 100.0);
   }
   if (button1.risingEdge()) {
-    granular1.shift(0, knobA2, knobA3);
+    granular1.stop();
   }
 
+  // continuously adjust pitch bend
+  granular1.rate(knobA2 * 1023.0);
 }