tube: add parameters with smoothing

crap/tube.h

@@ -1,22 +1,50 @@
 #include <string.h>
+#include <stdio.h>
 
 #include "util.h"
+#include "param.h"
 
 #define ID 0x50F7BA11
 #define LABEL "crap_tube"
 #define NAME "crap Tube Distortion"
 #define AUTHOR "Connor Olding"
 #define COPYRIGHT "MIT"
-#define PARAMETERS 0
+#define PARAMETERS 2
 
 #define HIST_SIZE   36
 #define HIST_SIZE_2 18
 
+typedef struct {
+	double desired, actual, speed;
+	int log; // use multiplication instead of addition for speed
+} smoothval;
+
 typedef struct {
 	double history_L[HIST_SIZE];
 	double history_R[HIST_SIZE];
+	smoothval drive, wet;
 } personal;
 
+static double
+smooth(smoothval *val)
+{
+	double a = val->actual;
+	double d = val->desired;
+	double s = val->speed;
+	double l = val->log;
+	if (a < d) {
+		if (l) a *= s;
+		else a += s;
+		if (a > d) a = d;
+	} else if (a > d) {
+		if (l) a /= s;
+		else a -= s;
+		if (a < d) a = d;
+	}
+	val->actual = a;
+	return a;
+}
+
 static double
 distort(double x)
 {
@@ -39,6 +67,8 @@ static double
 upsample(double h[HIST_SIZE_2], double x)
 {
 	double y;
+	// -3 at 18600/44100/2, -96 stopband
+	// designed with <https://coewww.rutgers.edu/~orfanidi/hpeq/>
 	LOWPASS(0, +0.71327159,+0.00688573,-0.45391337,+0.88734229);
 	LOWPASS(1, +0.63347126,+0.05572752,-0.36946634,+0.69213639);
 	LOWPASS(2, +0.55963645,+0.13990391,-0.26487901,+0.52405582);
@@ -55,6 +85,8 @@ static double
 downsample(double h[HIST_SIZE_2], double x)
 {
 	double y;
+	// -3 at 17544/44100/4, -96 stopband
+	// same idea as upsample()
 	LOWPASS(0, +0.62136966,-0.87573986,-1.56336581,+0.93036527);
 	LOWPASS(1, +0.56540370,-0.77393348,-1.44258778,+0.79946170);
 	LOWPASS(2, +0.49824084,-0.63630306,-1.31114921,+0.67132784);
@@ -68,14 +100,28 @@ downsample(double h[HIST_SIZE_2], double x)
 }
 
 static double
-process_one(double h[HIST_SIZE], double x)
+process_one(double x, double drive, double wet)
 {
+	return (distort(x*drive)/drive*0.79 - x)*wet + x;
+}
+
+static double
+oversample(personal *data, double x, int right)
+{
+	double *h0 = (!right) ? data->history_L : data->history_R;
+	double *h1 = h0 + HIST_SIZE_2;
 	double y;
-	y = downsample(h + HIST_SIZE_2, distort(4*upsample(h, x)));
+
-	    downsample(h + HIST_SIZE_2, distort(4*upsample(h, 0)));
+	#define doit(SAMP) \
-	    downsample(h + HIST_SIZE_2, distort(4*upsample(h, 0)));
+	downsample(h1, process_one(4*upsample(h0, SAMP), \
-	    downsample(h + HIST_SIZE_2, distort(4*upsample(h, 0)));
+	    smooth(&data->drive), smooth(&data->wet)))
-	return y*0.71;
+	y = doit(x);
+	    doit(0);
+	    doit(0);
+	    doit(0);
+	#undef doit
+
+	return y;
 }
 
 static void
@@ -86,8 +132,8 @@ process(personal *data,
 {
 	disable_denormals();
 	for (unsigned long pos = 0; pos < count; pos++) {
-		out_L[pos] = process_one(data->history_L, in_L[pos]);
+		out_L[pos] = oversample(data, in_L[pos], 0);
-		out_R[pos] = process_one(data->history_R, in_R[pos]);
+		out_R[pos] = oversample(data, in_R[pos], 1);
 	}
 }
 
@@ -99,8 +145,8 @@ process_double(personal *data,
 {
 	disable_denormals();
 	for (unsigned long pos = 0; pos < count; pos++) {
-		out_L[pos] = process_one(data->history_L, in_L[pos]);
+		out_L[pos] = oversample(data, in_L[pos], 0);
-		out_R[pos] = process_one(data->history_R, in_R[pos]);
+		out_R[pos] = oversample(data, in_R[pos], 1);
 	}
 }
 
@@ -118,14 +164,50 @@ pause(personal *data)
 static void
 construct(personal *data)
 {
-	resume(data);
+	memset(data, 0, sizeof(personal));
 }
+
+static void
+construct_params(param *params)
+{
+	sprintf(params[0].name, "Drive");
+	params[0].min = -30;
+	params[0].max = 15;
+	params[0].scale = SCALE_DB;
+	params[0].def = DEFAULT_0;
+
+	sprintf(params[1].name, "Wetness");
+	params[1].min = 0;
+	params[1].max = 1;
+	params[1].scale = SCALE_FLOAT;
+	params[1].def = DEFAULT_1;
+
+	param_reset(&params[0]);
+	param_reset(&params[1]);
+}
+
 static void
 destruct(personal *data)
 {}
 
 static void
-adjust(personal *data, unsigned long fs)
+adjust(personal *data, param *params, unsigned long fs_long)
 {
 	resume(data);
+	double fs = fs_long;
+	data->drive.desired = DB2LIN(params[0].value);
+	data->wet.desired = params[1].value;
+	data->drive.actual = data->drive.desired;
+	data->wet.actual = data->wet.desired;
+	data->drive.speed = 1 + 20/fs/4;
+	data->wet.speed = 20/fs/4;
+	data->drive.log = 1;
+	data->wet.log = 0;
+}
+
+static void
+adjust_one(personal *data, param *params, unsigned int index)
+{
+	data->drive.desired = DB2LIN(params[0].value);
+	data->wet.desired = params[1].value;
 }