aboutsummaryrefslogtreecommitdiffstats
path: root/plugins/LinuxVST/src/PurestEcho
diff options
context:
space:
mode:
authorChris Johnson <jinx6568@sover.net>2018-10-22 18:04:06 -0400
committerChris Johnson <jinx6568@sover.net>2018-10-22 18:04:06 -0400
commit633be2e22c6648c901f08f3b4cd4e8e14ea86443 (patch)
tree1e272c3d2b5bd29636b9f9f521af62734e4df012 /plugins/LinuxVST/src/PurestEcho
parent057757aa8eb0a463caf0cdfdb5894ac5f723ff3f (diff)
downloadairwindows-lv2-port-633be2e22c6648c901f08f3b4cd4e8e14ea86443.tar.gz
airwindows-lv2-port-633be2e22c6648c901f08f3b4cd4e8e14ea86443.tar.bz2
airwindows-lv2-port-633be2e22c6648c901f08f3b4cd4e8e14ea86443.zip
Updates (in case my plane crashes)
Diffstat (limited to 'plugins/LinuxVST/src/PurestEcho')
-rwxr-xr-xplugins/LinuxVST/src/PurestEcho/PurestEcho.cpp157
-rwxr-xr-xplugins/LinuxVST/src/PurestEcho/PurestEcho.h80
-rwxr-xr-xplugins/LinuxVST/src/PurestEcho/PurestEchoProc.cpp408
3 files changed, 645 insertions, 0 deletions
diff --git a/plugins/LinuxVST/src/PurestEcho/PurestEcho.cpp b/plugins/LinuxVST/src/PurestEcho/PurestEcho.cpp
new file mode 100755
index 0000000..6b8c302
--- /dev/null
+++ b/plugins/LinuxVST/src/PurestEcho/PurestEcho.cpp
@@ -0,0 +1,157 @@
+/* ========================================
+ * PurestEcho - PurestEcho.h
+ * Copyright (c) 2016 airwindows, All rights reserved
+ * ======================================== */
+
+#ifndef __PurestEcho_H
+#include "PurestEcho.h"
+#endif
+
+AudioEffect* createEffectInstance(audioMasterCallback audioMaster) {return new PurestEcho(audioMaster);}
+
+PurestEcho::PurestEcho(audioMasterCallback audioMaster) :
+ AudioEffectX(audioMaster, kNumPrograms, kNumParameters)
+{
+ A = 1.0;
+ B = 1.0;
+ C = 0.0;
+ D = 0.0;
+ E = 0.0;
+ for(int count = 0; count < totalsamples-1; count++) {dL[count] = 0;dR[count] = 0;}
+ gcount = 0;
+ fpNShapeLA = 0.0;
+ fpNShapeLB = 0.0;
+ fpNShapeRA = 0.0;
+ fpNShapeRB = 0.0;
+ fpFlip = true;
+ //this is reset: values being initialized only once. Startup values, whatever they are.
+
+ _canDo.insert("plugAsChannelInsert"); // plug-in can be used as a channel insert effect.
+ _canDo.insert("plugAsSend"); // plug-in can be used as a send effect.
+ _canDo.insert("x2in2out");
+ setNumInputs(kNumInputs);
+ setNumOutputs(kNumOutputs);
+ setUniqueID(kUniqueId);
+ canProcessReplacing(); // supports output replacing
+ canDoubleReplacing(); // supports double precision processing
+ programsAreChunks(true);
+ vst_strncpy (_programName, "Default", kVstMaxProgNameLen); // default program name
+}
+
+PurestEcho::~PurestEcho() {}
+VstInt32 PurestEcho::getVendorVersion () {return 1000;}
+void PurestEcho::setProgramName(char *name) {vst_strncpy (_programName, name, kVstMaxProgNameLen);}
+void PurestEcho::getProgramName(char *name) {vst_strncpy (name, _programName, kVstMaxProgNameLen);}
+//airwindows likes to ignore this stuff. Make your own programs, and make a different plugin rather than
+//trying to do versioning and preventing people from using older versions. Maybe they like the old one!
+
+static float pinParameter(float data)
+{
+ if (data < 0.0f) return 0.0f;
+ if (data > 1.0f) return 1.0f;
+ return data;
+}
+
+VstInt32 PurestEcho::getChunk (void** data, bool isPreset)
+{
+ float *chunkData = (float *)calloc(kNumParameters, sizeof(float));
+ chunkData[0] = A;
+ chunkData[1] = B;
+ chunkData[2] = C;
+ chunkData[3] = D;
+ chunkData[4] = E;
+ /* Note: The way this is set up, it will break if you manage to save settings on an Intel
+ machine and load them on a PPC Mac. However, it's fine if you stick to the machine you
+ started with. */
+
+ *data = chunkData;
+ return kNumParameters * sizeof(float);
+}
+
+VstInt32 PurestEcho::setChunk (void* data, VstInt32 byteSize, bool isPreset)
+{
+ float *chunkData = (float *)data;
+ A = pinParameter(chunkData[0]);
+ B = pinParameter(chunkData[1]);
+ C = pinParameter(chunkData[2]);
+ D = pinParameter(chunkData[3]);
+ E = pinParameter(chunkData[4]);
+ /* We're ignoring byteSize as we found it to be a filthy liar */
+
+ /* calculate any other fields you need here - you could copy in
+ code from setParameter() here. */
+ return 0;
+}
+
+void PurestEcho::setParameter(VstInt32 index, float value) {
+ switch (index) {
+ case kParamA: A = value; break;
+ case kParamB: B = value; break;
+ case kParamC: C = value; break;
+ case kParamD: D = value; break;
+ case kParamE: E = value; break;
+ default: throw; // unknown parameter, shouldn't happen!
+ }
+}
+
+float PurestEcho::getParameter(VstInt32 index) {
+ switch (index) {
+ case kParamA: return A; break;
+ case kParamB: return B; break;
+ case kParamC: return C; break;
+ case kParamD: return D; break;
+ case kParamE: return E; break;
+ default: break; // unknown parameter, shouldn't happen!
+ } return 0.0; //we only need to update the relevant name, this is simple to manage
+}
+
+void PurestEcho::getParameterName(VstInt32 index, char *text) {
+ switch (index) {
+ case kParamA: vst_strncpy (text, "Time", kVstMaxParamStrLen); break;
+ case kParamB: vst_strncpy (text, "Tap 1", kVstMaxParamStrLen); break;
+ case kParamC: vst_strncpy (text, "Tap 2", kVstMaxParamStrLen); break;
+ case kParamD: vst_strncpy (text, "Tap 3", kVstMaxParamStrLen); break;
+ case kParamE: vst_strncpy (text, "Tap 4", kVstMaxParamStrLen); break;
+ default: break; // unknown parameter, shouldn't happen!
+ } //this is our labels for displaying in the VST host
+}
+
+void PurestEcho::getParameterDisplay(VstInt32 index, char *text) {
+ switch (index) {
+ case kParamA: float2string (A, text, kVstMaxParamStrLen); break;
+ case kParamB: float2string (B, text, kVstMaxParamStrLen); break;
+ case kParamC: float2string (C, text, kVstMaxParamStrLen); break;
+ case kParamD: float2string (D, text, kVstMaxParamStrLen); break;
+ case kParamE: float2string (E, text, kVstMaxParamStrLen); break;
+
+ default: break; // unknown parameter, shouldn't happen!
+ } //this displays the values and handles 'popups' where it's discrete choices
+}
+
+void PurestEcho::getParameterLabel(VstInt32 index, char *text) {
+ switch (index) {
+ case kParamA: vst_strncpy (text, "", kVstMaxParamStrLen); break;
+ case kParamB: vst_strncpy (text, "", kVstMaxParamStrLen); break;
+ case kParamC: vst_strncpy (text, "", kVstMaxParamStrLen); break;
+ case kParamD: vst_strncpy (text, "", kVstMaxParamStrLen); break;
+ case kParamE: vst_strncpy (text, "", kVstMaxParamStrLen); break;
+ default: break; // unknown parameter, shouldn't happen!
+ }
+}
+
+VstInt32 PurestEcho::canDo(char *text)
+{ return (_canDo.find(text) == _canDo.end()) ? -1: 1; } // 1 = yes, -1 = no, 0 = don't know
+
+bool PurestEcho::getEffectName(char* name) {
+ vst_strncpy(name, "PurestEcho", kVstMaxProductStrLen); return true;
+}
+
+VstPlugCategory PurestEcho::getPlugCategory() {return kPlugCategEffect;}
+
+bool PurestEcho::getProductString(char* text) {
+ vst_strncpy (text, "airwindows PurestEcho", kVstMaxProductStrLen); return true;
+}
+
+bool PurestEcho::getVendorString(char* text) {
+ vst_strncpy (text, "airwindows", kVstMaxVendorStrLen); return true;
+}
diff --git a/plugins/LinuxVST/src/PurestEcho/PurestEcho.h b/plugins/LinuxVST/src/PurestEcho/PurestEcho.h
new file mode 100755
index 0000000..a298dd2
--- /dev/null
+++ b/plugins/LinuxVST/src/PurestEcho/PurestEcho.h
@@ -0,0 +1,80 @@
+/* ========================================
+ * PurestEcho - PurestEcho.h
+ * Created 8/12/11 by SPIAdmin
+ * Copyright (c) 2011 __MyCompanyName__, All rights reserved
+ * ======================================== */
+
+#ifndef __PurestEcho_H
+#define __PurestEcho_H
+
+#ifndef __audioeffect__
+#include "audioeffectx.h"
+#endif
+
+#include <set>
+#include <string>
+#include <math.h>
+
+enum {
+ kParamA = 0,
+ kParamB = 1,
+ kParamC = 2,
+ kParamD = 3,
+ kParamE = 4,
+ kNumParameters = 5
+}; //
+
+const int kNumPrograms = 0;
+const int kNumInputs = 2;
+const int kNumOutputs = 2;
+const unsigned long kUniqueId = 'pech'; //Change this to what the AU identity is!
+
+class PurestEcho :
+ public AudioEffectX
+{
+public:
+ PurestEcho(audioMasterCallback audioMaster);
+ ~PurestEcho();
+ virtual bool getEffectName(char* name); // The plug-in name
+ virtual VstPlugCategory getPlugCategory(); // The general category for the plug-in
+ virtual bool getProductString(char* text); // This is a unique plug-in string provided by Steinberg
+ virtual bool getVendorString(char* text); // Vendor info
+ virtual VstInt32 getVendorVersion(); // Version number
+ virtual void processReplacing (float** inputs, float** outputs, VstInt32 sampleFrames);
+ virtual void processDoubleReplacing (double** inputs, double** outputs, VstInt32 sampleFrames);
+ virtual void getProgramName(char *name); // read the name from the host
+ virtual void setProgramName(char *name); // changes the name of the preset displayed in the host
+ virtual VstInt32 getChunk (void** data, bool isPreset);
+ virtual VstInt32 setChunk (void* data, VstInt32 byteSize, bool isPreset);
+ virtual float getParameter(VstInt32 index); // get the parameter value at the specified index
+ virtual void setParameter(VstInt32 index, float value); // set the parameter at index to value
+ virtual void getParameterLabel(VstInt32 index, char *text); // label for the parameter (eg dB)
+ virtual void getParameterName(VstInt32 index, char *text); // name of the parameter
+ virtual void getParameterDisplay(VstInt32 index, char *text); // text description of the current value
+ virtual VstInt32 canDo(char *text);
+private:
+ char _programName[kVstMaxProgNameLen + 1];
+ std::set< std::string > _canDo;
+
+ const static int totalsamples = 65535;
+ double dL[totalsamples];
+ double dR[totalsamples];
+ int gcount;
+
+
+ long double fpNShapeLA;
+ long double fpNShapeLB;
+ long double fpNShapeRA;
+ long double fpNShapeRB;
+ bool fpFlip;
+ //default stuff
+
+ float A;
+ float B;
+ float C;
+ float D;
+ float E; //parameters. Always 0-1, and we scale/alter them elsewhere.
+
+};
+
+#endif
diff --git a/plugins/LinuxVST/src/PurestEcho/PurestEchoProc.cpp b/plugins/LinuxVST/src/PurestEcho/PurestEchoProc.cpp
new file mode 100755
index 0000000..77e4b2f
--- /dev/null
+++ b/plugins/LinuxVST/src/PurestEcho/PurestEchoProc.cpp
@@ -0,0 +1,408 @@
+/* ========================================
+ * PurestEcho - PurestEcho.h
+ * Copyright (c) 2016 airwindows, All rights reserved
+ * ======================================== */
+
+#ifndef __PurestEcho_H
+#include "PurestEcho.h"
+#endif
+
+void PurestEcho::processReplacing(float **inputs, float **outputs, VstInt32 sampleFrames)
+{
+ float* in1 = inputs[0];
+ float* in2 = inputs[1];
+ float* out1 = outputs[0];
+ float* out2 = outputs[1];
+
+ int loopLimit = (int)(totalsamples * 0.499);
+ //this is a double buffer so we will be splitting it in two
+
+ double time = pow(A,2) * 0.999;
+ double tap1 = B;
+ double tap2 = C;
+ double tap3 = D;
+ double tap4 = E;
+
+ double gainTrim = 1.0 / (1.0 + tap1 + tap2 + tap3 + tap4);
+ //this becomes our equal-loudness mechanic. 0.2 to 1.0 gain on all things.
+ double tapsTrim = gainTrim * 0.5;
+ //the taps interpolate and require half that gain: 0.1 to 0.5 on all taps.
+
+ int position1 = (int)(loopLimit * time * 0.25);
+ int position2 = (int)(loopLimit * time * 0.5);
+ int position3 = (int)(loopLimit * time * 0.75);
+ int position4 = (int)(loopLimit * time);
+ //basic echo information: we're taking four equally spaced echoes and setting their levels as desired.
+ //position4 is what you'd have for 'just set a delay time'
+
+ double volAfter1 = (loopLimit * time * 0.25) - position1;
+ double volAfter2 = (loopLimit * time * 0.5) - position2;
+ double volAfter3 = (loopLimit * time * 0.75) - position3;
+ double volAfter4 = (loopLimit * time) - position4;
+ //these are 0-1: casting to an (int) truncates fractional numbers towards zero (and is faster than floor() )
+ //so, when we take the integer number (all above zero) and subtract it from the real value, we get 0-1
+ double volBefore1 = (1.0 - volAfter1) * tap1;
+ double volBefore2 = (1.0 - volAfter2) * tap2;
+ double volBefore3 = (1.0 - volAfter3) * tap3;
+ double volBefore4 = (1.0 - volAfter4) * tap4;
+ //and if we are including a bit of the previous/next sample to interpolate, then if the sample position is 1.0001
+ //we'll be leaning most heavily on the 'before' sample which is nearer to us, and the 'after' sample is almost not used.
+ //if the sample position is 1.9999, the 'after' sample is strong and 'before' is almost not used.
+
+ volAfter1 *= tap1;
+ volAfter2 *= tap2;
+ volAfter3 *= tap3;
+ volAfter4 *= tap4;
+ //and like with volBefore, we also want to scale this 'interpolate' to the loudness of this tap.
+ //We do it here because we can do it only once per audio buffer, not on every sample. This assumes we're
+ //not moving the tap every sample: if so we'd have to do this every sample as well.
+
+ int oneBefore1 = position1 - 1;
+ int oneBefore2 = position2 - 1;
+ int oneBefore3 = position3 - 1;
+ int oneBefore4 = position4 - 1;
+ if (oneBefore1 < 0) oneBefore1 = 0;
+ if (oneBefore2 < 0) oneBefore2 = 0;
+ if (oneBefore3 < 0) oneBefore3 = 0;
+ if (oneBefore4 < 0) oneBefore4 = 0;
+ int oneAfter1 = position1 + 1;
+ int oneAfter2 = position2 + 1;
+ int oneAfter3 = position3 + 1;
+ int oneAfter4 = position4 + 1;
+ //this is setting up the way we interpolate samples: we're doing an echo-darkening thing
+ //to make it sound better. Pretty much no acoustic delay in human-breathable air will give
+ //you zero attenuation at 22 kilohertz: forget this at your peril ;)
+
+ double delaysBufferL;
+ double delaysBufferR;
+
+ float fpTemp;
+ long double fpOld = 0.618033988749894848204586; //golden ratio!
+ long double fpNew = 1.0 - fpOld;
+
+ long double inputSampleL;
+ long double inputSampleR;
+
+ while (--sampleFrames >= 0)
+ {
+ inputSampleL = *in1;
+ inputSampleR = *in2;
+ if (inputSampleL<1.2e-38 && -inputSampleL<1.2e-38) {
+ static int noisesource = 0;
+ //this declares a variable before anything else is compiled. It won't keep assigning
+ //it to 0 for every sample, it's as if the declaration doesn't exist in this context,
+ //but it lets me add this denormalization fix in a single place rather than updating
+ //it in three different locations. The variable isn't thread-safe but this is only
+ //a random seed and we can share it with whatever.
+ noisesource = noisesource % 1700021; noisesource++;
+ int residue = noisesource * noisesource;
+ residue = residue % 170003; residue *= residue;
+ residue = residue % 17011; residue *= residue;
+ residue = residue % 1709; residue *= residue;
+ residue = residue % 173; residue *= residue;
+ residue = residue % 17;
+ double applyresidue = residue;
+ applyresidue *= 0.00000001;
+ applyresidue *= 0.00000001;
+ inputSampleL = applyresidue;
+ }
+ if (inputSampleR<1.2e-38 && -inputSampleR<1.2e-38) {
+ static int noisesource = 0;
+ noisesource = noisesource % 1700021; noisesource++;
+ int residue = noisesource * noisesource;
+ residue = residue % 170003; residue *= residue;
+ residue = residue % 17011; residue *= residue;
+ residue = residue % 1709; residue *= residue;
+ residue = residue % 173; residue *= residue;
+ residue = residue % 17;
+ double applyresidue = residue;
+ applyresidue *= 0.00000001;
+ applyresidue *= 0.00000001;
+ inputSampleR = applyresidue;
+ //this denormalization routine produces a white noise at -300 dB which the noise
+ //shaping will interact with to produce a bipolar output, but the noise is actually
+ //all positive. That should stop any variables from going denormal, and the routine
+ //only kicks in if digital black is input. As a final touch, if you save to 24-bit
+ //the silence will return to being digital black again.
+ }
+
+ if (gcount < 0 || gcount > loopLimit) gcount = loopLimit;
+ dL[gcount+loopLimit] = dL[gcount] = inputSampleL * tapsTrim;
+ dR[gcount+loopLimit] = dR[gcount] = inputSampleR * tapsTrim; //this is how the double buffer works:
+ //we can look for delay taps without ever having to 'wrap around' within our calculation.
+ //As long as the delay tap is less than our loop limit we can always just add it to where we're
+ //at, and get a valid sample back right away, no matter where we are in the buffer.
+ //The 0.5 is taking into account the interpolation, by padding down the whole buffer.
+
+ delaysBufferL = (dL[gcount+oneBefore4]*volBefore4);
+ delaysBufferL += (dL[gcount+oneAfter4]*volAfter4);
+ delaysBufferL += (dL[gcount+oneBefore3]*volBefore3);
+ delaysBufferL += (dL[gcount+oneAfter3]*volAfter3);
+ delaysBufferL += (dL[gcount+oneBefore2]*volBefore2);
+ delaysBufferL += (dL[gcount+oneAfter2]*volAfter2);
+ delaysBufferL += (dL[gcount+oneBefore1]*volBefore1);
+ delaysBufferL += (dL[gcount+oneAfter1]*volAfter1);
+
+ delaysBufferR = (dR[gcount+oneBefore4]*volBefore4);
+ delaysBufferR += (dR[gcount+oneAfter4]*volAfter4);
+ delaysBufferR += (dR[gcount+oneBefore3]*volBefore3);
+ delaysBufferR += (dR[gcount+oneAfter3]*volAfter3);
+ delaysBufferR += (dR[gcount+oneBefore2]*volBefore2);
+ delaysBufferR += (dR[gcount+oneAfter2]*volAfter2);
+ delaysBufferR += (dR[gcount+oneBefore1]*volBefore1);
+ delaysBufferR += (dR[gcount+oneAfter1]*volAfter1);
+ //These are the interpolated samples. We're adding them first, because we know they're smaller
+ //and while the value of delaysBuffer is small we'll add similarly small values to it. Note the order.
+
+ delaysBufferL += (dL[gcount+position4]*tap4);
+ delaysBufferL += (dL[gcount+position3]*tap3);
+ delaysBufferL += (dL[gcount+position2]*tap2);
+ delaysBufferL += (dL[gcount+position1]*tap1);
+
+ delaysBufferR += (dR[gcount+position4]*tap4);
+ delaysBufferR += (dR[gcount+position3]*tap3);
+ delaysBufferR += (dR[gcount+position2]*tap2);
+ delaysBufferR += (dR[gcount+position1]*tap1);
+ //These are the primary samples for the echo, and we're adding them last. As before we're starting with the
+ //most delayed echoes, and ending with what we think might be the loudest echo. We're building this delaybuffer
+ //from the faintest noises to the loudest, to avoid adding a bunch of teeny values at the end.
+ //You can of course put the last echo as loudest, but with diminishing echo volumes this is optimal.
+ //This technique is also present in other plugins such as Iron Oxide.
+
+ inputSampleL = (inputSampleL * gainTrim) + delaysBufferL;
+ inputSampleR = (inputSampleR * gainTrim) + delaysBufferR;
+ //this could be just inputSample += d[gcount+position1];
+ //for literally a single, full volume echo combined with dry.
+ //What I'm doing is making the echoes more interesting.
+
+ gcount--;
+
+ //noise shaping to 32-bit floating point
+ if (fpFlip) {
+ fpTemp = inputSampleL;
+ fpNShapeLA = (fpNShapeLA*fpOld)+((inputSampleL-fpTemp)*fpNew);
+ inputSampleL += fpNShapeLA;
+ fpTemp = inputSampleR;
+ fpNShapeRA = (fpNShapeRA*fpOld)+((inputSampleR-fpTemp)*fpNew);
+ inputSampleR += fpNShapeRA;
+ }
+ else {
+ fpTemp = inputSampleL;
+ fpNShapeLB = (fpNShapeLB*fpOld)+((inputSampleL-fpTemp)*fpNew);
+ inputSampleL += fpNShapeLB;
+ fpTemp = inputSampleR;
+ fpNShapeRB = (fpNShapeRB*fpOld)+((inputSampleR-fpTemp)*fpNew);
+ inputSampleR += fpNShapeRB;
+ }
+ fpFlip = !fpFlip;
+ //end noise shaping on 32 bit output
+
+ *out1 = inputSampleL;
+ *out2 = inputSampleR;
+
+ *in1++;
+ *in2++;
+ *out1++;
+ *out2++;
+ }
+}
+
+void PurestEcho::processDoubleReplacing(double **inputs, double **outputs, VstInt32 sampleFrames)
+{
+ double* in1 = inputs[0];
+ double* in2 = inputs[1];
+ double* out1 = outputs[0];
+ double* out2 = outputs[1];
+
+ int loopLimit = (int)(totalsamples * 0.499);
+ //this is a double buffer so we will be splitting it in two
+
+ double time = pow(A,2) * 0.999;
+ double tap1 = B;
+ double tap2 = C;
+ double tap3 = D;
+ double tap4 = E;
+
+ double gainTrim = 1.0 / (1.0 + tap1 + tap2 + tap3 + tap4);
+ //this becomes our equal-loudness mechanic. 0.2 to 1.0 gain on all things.
+ double tapsTrim = gainTrim * 0.5;
+ //the taps interpolate and require half that gain: 0.1 to 0.5 on all taps.
+
+ int position1 = (int)(loopLimit * time * 0.25);
+ int position2 = (int)(loopLimit * time * 0.5);
+ int position3 = (int)(loopLimit * time * 0.75);
+ int position4 = (int)(loopLimit * time);
+ //basic echo information: we're taking four equally spaced echoes and setting their levels as desired.
+ //position4 is what you'd have for 'just set a delay time'
+
+ double volAfter1 = (loopLimit * time * 0.25) - position1;
+ double volAfter2 = (loopLimit * time * 0.5) - position2;
+ double volAfter3 = (loopLimit * time * 0.75) - position3;
+ double volAfter4 = (loopLimit * time) - position4;
+ //these are 0-1: casting to an (int) truncates fractional numbers towards zero (and is faster than floor() )
+ //so, when we take the integer number (all above zero) and subtract it from the real value, we get 0-1
+ double volBefore1 = (1.0 - volAfter1) * tap1;
+ double volBefore2 = (1.0 - volAfter2) * tap2;
+ double volBefore3 = (1.0 - volAfter3) * tap3;
+ double volBefore4 = (1.0 - volAfter4) * tap4;
+ //and if we are including a bit of the previous/next sample to interpolate, then if the sample position is 1.0001
+ //we'll be leaning most heavily on the 'before' sample which is nearer to us, and the 'after' sample is almost not used.
+ //if the sample position is 1.9999, the 'after' sample is strong and 'before' is almost not used.
+
+ volAfter1 *= tap1;
+ volAfter2 *= tap2;
+ volAfter3 *= tap3;
+ volAfter4 *= tap4;
+ //and like with volBefore, we also want to scale this 'interpolate' to the loudness of this tap.
+ //We do it here because we can do it only once per audio buffer, not on every sample. This assumes we're
+ //not moving the tap every sample: if so we'd have to do this every sample as well.
+
+ int oneBefore1 = position1 - 1;
+ int oneBefore2 = position2 - 1;
+ int oneBefore3 = position3 - 1;
+ int oneBefore4 = position4 - 1;
+ if (oneBefore1 < 0) oneBefore1 = 0;
+ if (oneBefore2 < 0) oneBefore2 = 0;
+ if (oneBefore3 < 0) oneBefore3 = 0;
+ if (oneBefore4 < 0) oneBefore4 = 0;
+ int oneAfter1 = position1 + 1;
+ int oneAfter2 = position2 + 1;
+ int oneAfter3 = position3 + 1;
+ int oneAfter4 = position4 + 1;
+ //this is setting up the way we interpolate samples: we're doing an echo-darkening thing
+ //to make it sound better. Pretty much no acoustic delay in human-breathable air will give
+ //you zero attenuation at 22 kilohertz: forget this at your peril ;)
+
+ double delaysBufferL;
+ double delaysBufferR;
+
+ double fpTemp; //this is different from singlereplacing
+ long double fpOld = 0.618033988749894848204586; //golden ratio!
+ long double fpNew = 1.0 - fpOld;
+
+ long double inputSampleL;
+ long double inputSampleR;
+
+ while (--sampleFrames >= 0)
+ {
+ inputSampleL = *in1;
+ inputSampleR = *in2;
+ if (inputSampleL<1.2e-38 && -inputSampleL<1.2e-38) {
+ static int noisesource = 0;
+ //this declares a variable before anything else is compiled. It won't keep assigning
+ //it to 0 for every sample, it's as if the declaration doesn't exist in this context,
+ //but it lets me add this denormalization fix in a single place rather than updating
+ //it in three different locations. The variable isn't thread-safe but this is only
+ //a random seed and we can share it with whatever.
+ noisesource = noisesource % 1700021; noisesource++;
+ int residue = noisesource * noisesource;
+ residue = residue % 170003; residue *= residue;
+ residue = residue % 17011; residue *= residue;
+ residue = residue % 1709; residue *= residue;
+ residue = residue % 173; residue *= residue;
+ residue = residue % 17;
+ double applyresidue = residue;
+ applyresidue *= 0.00000001;
+ applyresidue *= 0.00000001;
+ inputSampleL = applyresidue;
+ }
+ if (inputSampleR<1.2e-38 && -inputSampleR<1.2e-38) {
+ static int noisesource = 0;
+ noisesource = noisesource % 1700021; noisesource++;
+ int residue = noisesource * noisesource;
+ residue = residue % 170003; residue *= residue;
+ residue = residue % 17011; residue *= residue;
+ residue = residue % 1709; residue *= residue;
+ residue = residue % 173; residue *= residue;
+ residue = residue % 17;
+ double applyresidue = residue;
+ applyresidue *= 0.00000001;
+ applyresidue *= 0.00000001;
+ inputSampleR = applyresidue;
+ //this denormalization routine produces a white noise at -300 dB which the noise
+ //shaping will interact with to produce a bipolar output, but the noise is actually
+ //all positive. That should stop any variables from going denormal, and the routine
+ //only kicks in if digital black is input. As a final touch, if you save to 24-bit
+ //the silence will return to being digital black again.
+ }
+
+ if (gcount < 0 || gcount > loopLimit) gcount = loopLimit;
+ dL[gcount+loopLimit] = dL[gcount] = inputSampleL * tapsTrim;
+ dR[gcount+loopLimit] = dR[gcount] = inputSampleR * tapsTrim; //this is how the double buffer works:
+ //we can look for delay taps without ever having to 'wrap around' within our calculation.
+ //As long as the delay tap is less than our loop limit we can always just add it to where we're
+ //at, and get a valid sample back right away, no matter where we are in the buffer.
+ //The 0.5 is taking into account the interpolation, by padding down the whole buffer.
+
+ delaysBufferL = (dL[gcount+oneBefore4]*volBefore4);
+ delaysBufferL += (dL[gcount+oneAfter4]*volAfter4);
+ delaysBufferL += (dL[gcount+oneBefore3]*volBefore3);
+ delaysBufferL += (dL[gcount+oneAfter3]*volAfter3);
+ delaysBufferL += (dL[gcount+oneBefore2]*volBefore2);
+ delaysBufferL += (dL[gcount+oneAfter2]*volAfter2);
+ delaysBufferL += (dL[gcount+oneBefore1]*volBefore1);
+ delaysBufferL += (dL[gcount+oneAfter1]*volAfter1);
+
+ delaysBufferR = (dR[gcount+oneBefore4]*volBefore4);
+ delaysBufferR += (dR[gcount+oneAfter4]*volAfter4);
+ delaysBufferR += (dR[gcount+oneBefore3]*volBefore3);
+ delaysBufferR += (dR[gcount+oneAfter3]*volAfter3);
+ delaysBufferR += (dR[gcount+oneBefore2]*volBefore2);
+ delaysBufferR += (dR[gcount+oneAfter2]*volAfter2);
+ delaysBufferR += (dR[gcount+oneBefore1]*volBefore1);
+ delaysBufferR += (dR[gcount+oneAfter1]*volAfter1);
+ //These are the interpolated samples. We're adding them first, because we know they're smaller
+ //and while the value of delaysBuffer is small we'll add similarly small values to it. Note the order.
+
+ delaysBufferL += (dL[gcount+position4]*tap4);
+ delaysBufferL += (dL[gcount+position3]*tap3);
+ delaysBufferL += (dL[gcount+position2]*tap2);
+ delaysBufferL += (dL[gcount+position1]*tap1);
+
+ delaysBufferR += (dR[gcount+position4]*tap4);
+ delaysBufferR += (dR[gcount+position3]*tap3);
+ delaysBufferR += (dR[gcount+position2]*tap2);
+ delaysBufferR += (dR[gcount+position1]*tap1);
+ //These are the primary samples for the echo, and we're adding them last. As before we're starting with the
+ //most delayed echoes, and ending with what we think might be the loudest echo. We're building this delaybuffer
+ //from the faintest noises to the loudest, to avoid adding a bunch of teeny values at the end.
+ //You can of course put the last echo as loudest, but with diminishing echo volumes this is optimal.
+ //This technique is also present in other plugins such as Iron Oxide.
+
+ inputSampleL = (inputSampleL * gainTrim) + delaysBufferL;
+ inputSampleR = (inputSampleR * gainTrim) + delaysBufferR;
+ //this could be just inputSample += d[gcount+position1];
+ //for literally a single, full volume echo combined with dry.
+ //What I'm doing is making the echoes more interesting.
+
+ gcount--;
+
+ //noise shaping to 64-bit floating point
+ if (fpFlip) {
+ fpTemp = inputSampleL;
+ fpNShapeLA = (fpNShapeLA*fpOld)+((inputSampleL-fpTemp)*fpNew);
+ inputSampleL += fpNShapeLA;
+ fpTemp = inputSampleR;
+ fpNShapeRA = (fpNShapeRA*fpOld)+((inputSampleR-fpTemp)*fpNew);
+ inputSampleR += fpNShapeRA;
+ }
+ else {
+ fpTemp = inputSampleL;
+ fpNShapeLB = (fpNShapeLB*fpOld)+((inputSampleL-fpTemp)*fpNew);
+ inputSampleL += fpNShapeLB;
+ fpTemp = inputSampleR;
+ fpNShapeRB = (fpNShapeRB*fpOld)+((inputSampleR-fpTemp)*fpNew);
+ inputSampleR += fpNShapeRB;
+ }
+ fpFlip = !fpFlip;
+ //end noise shaping on 64 bit output
+
+ *out1 = inputSampleL;
+ *out2 = inputSampleR;
+
+ *in1++;
+ *in2++;
+ *out1++;
+ *out2++;
+ }
+} \ No newline at end of file