Added Ping Pong Mode and Mix control to Delay FX

src/effect_delay.cpp

@@ -1,3 +1,7 @@
+/* 
+ * Stereo Delay
+ * Javier Nonis (https://github.com/jnonis) - 2024
+ */
 #include <circle/logger.h>
 #include "effect_delay.h"
 
@@ -19,7 +23,9 @@ AudioEffectDelay::AudioEffectDelay(float32_t samplerate) : AudioEffect(samplerat
     
     this->timeL = 0.36f;
     this->timeR = 0.36f;
-    this->feedback = 0.5f;
+    this->feedback = 0.6f;
+    this->pingPongMode = false;
+    this->setMix(0.5f);
 }
 
 AudioEffectDelay::~AudioEffectDelay()
@@ -53,6 +59,12 @@ void AudioEffectDelay::setParameter(unsigned param, unsigned value)
     case AudioEffectDelay::Param::TONE:
         this->lpf->setParameter(AudioEffectLPF::Param::CUTOFF, value);
         break;
+    case AudioEffectDelay::Param::PING_PONG:
+        this->pingPongMode = (value == 1);
+        break;
+    case AudioEffectDelay::Param::MIX:
+        this->setMix((float32_t) value / 100.0f);
+        break;
     default:
         break;
     }
@@ -72,35 +84,80 @@ unsigned AudioEffectDelay::getParameter(unsigned param)
         return roundf(this->feedback * 100);
     case AudioEffectDelay::Param::TONE:
         return this->lpf->getParameter(AudioEffectLPF::Param::CUTOFF);
+    case AudioEffectDelay::Param::PING_PONG:
+        return this->pingPongMode ? 1 : 0;
+    case AudioEffectDelay::Param::MIX:
+        return roundf(this->mix * 100);
     default:
         return 0;
     }
 }
 
+void AudioEffectDelay::setMix(float32_t mix)
+{
+    this->mix = mix;
+    if (this->mix <= 0.5f)
+    {
+        this->dryMix = 1.0f;
+        this->wetMix = this->mix * 2;
+    }
+    else
+    {
+        this->dryMix = 1.0f - ((this->mix - 0.5f) * 2);
+        this->wetMix = 1.0f;
+    }
+}
 
 void AudioEffectDelay::doProcess(const float32_t* inblockL, const float32_t* inblockR, float32_t* outblockL, float32_t* outblockR, uint16_t len)
 {
     for (uint16_t i=0; i < len; i++) 
     {
-        // Update buffers
-        this->bufferL[index] = inblockL[i];
-        this->bufferR[index] = inblockR[i];
-
-        // Calculate offsets
-        int offsetL = this->index - (this->timeL * this->samplerate);
-        if (offsetL < 0) {
-            offsetL = this->bufferSize + offsetL;
-        }
-        int offsetR = this->index - (this->timeR * this->samplerate);
-        if (offsetR < 0) {
-            offsetR = this->bufferSize + offsetR;
+        float32_t inL = inblockL[i];
+        float32_t inR = inblockR[i];
+        if (this->pingPongMode)
+        {
+            // Ping Pong mode only uses timeL
+            // Calculate offsets
+            int offsetL = this->index - (this->timeL * this->samplerate);
+            if (offsetL < 0)
+            {
+                offsetL = this->bufferSize + offsetL;
+            }
+            
+            // We need to feed the buffers each other
+            this->bufferL[index] = this->lpf->processSampleR(this->bufferR[offsetL]) * this->feedback;
+            this->bufferR[index] = this->lpf->processSampleL(this->bufferL[offsetL]) * this->feedback;
+
+            outblockL[i] = (inL * this->dryMix) + (this->bufferL[index] * this->wetMix);
+            outblockR[i] = (inR * this->dryMix) + (this->bufferR[index] * this->wetMix);
+
+            // Update buffers
+            this->bufferL[index] += (inL + inR) * 0.5f;
         }
+        else
+        {
+            // Calculate offsets
+            int offsetL = this->index - (this->timeL * this->samplerate);
+            if (offsetL < 0)
+            {
+                offsetL = this->bufferSize + offsetL;
+            }
+            int offsetR = this->index - (this->timeR * this->samplerate);
+            if (offsetR < 0)
+            {
+                offsetR = this->bufferSize + offsetR;
+            }
 
-        this->bufferL[index] += this->lpf->processSampleL(this->bufferL[offsetL]) * this->feedback;
-        this->bufferR[index] += this->lpf->processSampleR(this->bufferR[offsetR]) * this->feedback;
+            this->bufferL[index] = this->lpf->processSampleL(this->bufferL[offsetL]) * this->feedback;
+            this->bufferR[index] = this->lpf->processSampleR(this->bufferR[offsetR]) * this->feedback;
             
-        outblockL[i] = this->bufferL[index];
-        outblockR[i] = this->bufferR[index];
+            outblockL[i] = (inL * this->dryMix) + (this->bufferL[index] * this->wetMix);
+            outblockR[i] = (inR * this->dryMix) + (this->bufferR[index] * this->wetMix);
+
+            // Update buffers
+            this->bufferL[index] += inL;
+            this->bufferR[index] += inR;
+        }
 
         // Update index
         this->index++;

src/effect_delay.h

@@ -1,3 +1,10 @@
+/* 
+ * Stereo Delay
+ * Features:
+ * - Tone control using Low Pass Filter
+ * - Ping Pong mode.
+ * Javier Nonis (https://github.com/jnonis) - 2024
+ */
 #ifndef _EFFECT_DELAY_H
 #define _EFFECT_DELAY_H
 
@@ -16,6 +23,8 @@ public:
         TIME_R,
         FEEDBACK,
         TONE,
+        PING_PONG,
+        MIX,
         UNKNOWN
     };
 
@@ -41,6 +50,12 @@ private:
     float32_t timeR; // Right delay time in seconds (0.0 - 2.0)
     float32_t feedback; // Feedback (0.0 - 1.0)
     AudioEffectLPF* lpf;
+    bool pingPongMode;
+    float32_t mix;
+    float32_t dryMix;
+    float32_t wetMix;
+    
+    void setMix(float32_t mix);
 };
 
 #endif // _EFFECT_DELAY_H

src/uimenu.cpp

@@ -167,6 +167,8 @@ const CUIMenu::TMenuItem CUIMenu::s_FXDelay[] =
 	{"Time R", EditTGFXParameter, 0, AudioEffectDelay::Param::TIME_R},
 	{"Feedback", EditTGFXParameter, 0, AudioEffectDelay::Param::FEEDBACK},
 	{"Tone", EditTGFXParameter, 0, AudioEffectDelay::Param::TONE},
+	{"Ping Pong", EditTGFXParameter, 0, AudioEffectDelay::Param::PING_PONG},
+	{"Mix", EditTGFXParameter, 0, AudioEffectDelay::Param::MIX},
 	{0}
 };
 
@@ -349,7 +351,9 @@ const CUIMenu::TParameter CUIMenu::s_TGFXDelayParam[AudioEffectDelay::Param::UNK
 	{0, AudioEffectDelay::MAX_DELAY_TIME * 1000, 1}, // TIME_L
 	{0, AudioEffectDelay::MAX_DELAY_TIME * 1000, 1}, // TIME_R
 	{0, 100, 1}, // FEEDBACK,
-	{0, 100, 1} // TONE
+	{0, 100, 1}, // TONE
+	{0, 1, 1, ToOnOff}, // PING_PONG
+	{0, 100, 1} // MIX
 };
 
 // must match AudioEffectLPF::Param