Diffuser

Makefile

@@ -19,6 +19,7 @@ compressor \
 crossfade \
 dcblock \
 decimator \
+diffuser \
 drip \
 fm2 \
 fold \

daisysp.h

@@ -34,13 +34,15 @@
 #include "modules/dcblock.h"
 #include "modules/decimator.h"
 #include "modules/delayline.h"
+#include "modules/diffuser.h"
 #include "modules/drip.h"
 #include "modules/dsp.h"
 #include "modules/dust.h"
 #include "modules/fm2.h"
 #include "modules/fold.h"
 #include "modules/formantosc.h"
 #include "modules/fractal_noise.h"
+#include "modules/fx_engine.h"
 #include "modules/grainlet.h"
 #include "modules/harmonic_osc.h"
 #include "modules/hihat.h"

modules/diffuser.cpp

@@ -0,0 +1,64 @@
+#include "dsp.h"
+#include "diffuser.h"
+#include <math.h>
+
+using namespace daisysp;
+
+void Diffuser::Init()
+{
+    engine_.Init(buffer_);
+    engine_.SetLFOFrequency(LFO_1, 0.3f / 48000.0f);
+    lp_decay_ = 0.0f;
+
+    SetAmount(1.f);
+    SetTime(.5f);
+}
+
+float Diffuser::Process(float in)
+{
+    typedef E::Reserve<
+        126,
+        E::Reserve<
+            180,
+            E::Reserve<
+                269,
+                E::Reserve<
+                    444,
+                    E::Reserve<1653, E::Reserve<2010, E::Reserve<3411>>>>>>>
+                            Memory;
+    E::DelayLine<Memory, 0> ap1;
+    E::DelayLine<Memory, 1> ap2;
+    E::DelayLine<Memory, 2> ap3;
+    E::DelayLine<Memory, 3> ap4;
+    E::DelayLine<Memory, 4> dapa;
+    E::DelayLine<Memory, 5> dapb;
+    E::DelayLine<Memory, 6> del;
+    E::Context              c;
+    const float             kap = 0.625f;
+    const float             klp = 0.75f;
+    float                   lp  = lp_decay_;
+
+    float wet;
+    engine_.Start(&c);
+    c.Read(in);
+    c.Read(ap1 TAIL, kap);
+    c.WriteAllPass(ap1, -kap);
+    c.Read(ap2 TAIL, kap);
+    c.WriteAllPass(ap2, -kap);
+    c.Read(ap3 TAIL, kap);
+    c.WriteAllPass(ap3, -kap);
+    c.Interpolate(ap4, 400.0f, LFO_1, 43.0f, kap);
+    c.WriteAllPass(ap4, -kap);
+    c.Interpolate(del, 3070.0f, LFO_1, 340.0f, rt_);
+    c.Lp(lp, klp);
+    c.Read(dapa TAIL, -kap);
+    c.WriteAllPass(dapa, kap);
+    c.Read(dapb TAIL, kap);
+    c.WriteAllPass(dapb, -kap);
+    c.Write(del, 2.0f);
+    c.Write(wet, 0.0f);
+
+    lp_decay_ = lp;
+
+    return .1f * amount_ * (wet - in);
+}

modules/diffuser.h

@@ -0,0 +1,60 @@
+#pragma once
+#ifndef DSY_DIFFUSER_H
+#define DSY_DIFFUSER_H
+
+#include "modules/fx_engine.h"
+
+#include <stdint.h>
+#ifdef __cplusplus
+
+/** @file diffuser.h */
+
+namespace daisysp
+{
+/**  
+       @brief Granular Diffuser
+	   @author Ben Sergentanis
+	   @date Jan 2021
+	   Ported from pichenettes/eurorack/plaits/dsp/fx/diffuser.h \n
+	   to an independent module. \n
+	   Original code written by Emilie Gillet in 2016. \n
+*/
+class Diffuser
+{
+  public:
+    Diffuser() {}
+    ~Diffuser() {}
+
+    /** Initialize the module
+	*/
+    void Init();
+
+    /** Reset the reverb */
+    void Clear() { engine_.Clear(); }
+
+    /** Get the next sample
+		\param in Next sample to process
+	*/
+    float Process(float in);
+
+    /** Set the reverb tail length
+		\param rt Works 0-1.
+	*/
+    void SetTime(float rt) { rt_ = fclamp(rt, 0.f, 1.f); }
+
+    /** Set the amount of reverb.
+		\param amount Works 0-1.
+	*/
+    void SetAmount(float amount) { amount_ = fclamp(amount, 0.f, 1.f); };
+
+  private:
+    float rt_, amount_;
+
+    uint16_t                              buffer_[8192];
+    typedef FxEngine<8192, FORMAT_12_BIT> E;
+    E                                     engine_;
+    float                                 lp_decay_;
+};
+} // namespace daisysp
+#endif
+#endif