X-Git-Url: https://git.sesse.net/?p=nageru;a=blobdiff_plain;f=filter.cpp;h=0cb0180d8c4ce4f673112422708f68f5608f9b4d;hp=a5cd76733f3f5325af1c511a3f4c007e6c6cf8e9;hb=703e00da89118df9be0354dda621bed023e6030e;hpb=12f9082b06c037b76dc3a653643bdaeaea89f2d2

diff --git a/filter.cpp b/filter.cpp
index a5cd767..0cb0180 100644
--- a/filter.cpp
+++ b/filter.cpp
@@ -1,9 +1,11 @@
+#include <assert.h>
 #include <math.h>
 #include <stdio.h>
 #include <string.h>
-#include <assert.h>
-#include <complex>
 #include <algorithm>
+#include <complex>
+
+#include "defs.h"
 
 #ifdef __SSE__
 #include <mmintrin.h>
@@ -11,6 +13,8 @@
 
 #include "filter.h"
 
+using namespace std;
+
 #ifdef __SSE__
 
 // For SSE, we set the denormals-as-zero flag instead.
@@ -34,6 +38,7 @@ Filter::Filter()
 {
 	omega = M_PI;
 	resonance = 0.01f;
+	A = 1.0f;
 
 	init(FILTER_NONE, 1);
 	update();
@@ -49,8 +54,8 @@ void Filter::update()
 
 	float sn, cs;
 	float cutoff_freq = omega;
-	cutoff_freq = std::min(cutoff_freq, (float)M_PI);
-	cutoff_freq = std::max(cutoff_freq, 0.001f);
+	cutoff_freq = min(cutoff_freq, (float)M_PI);
+	cutoff_freq = max(cutoff_freq, 0.001f);
 	calcSinCos(cutoff_freq, &sn, &cs);
 	if (resonance <= 0) resonance = 0.001f;
 
@@ -129,6 +134,33 @@ void Filter::update()
 		// a2 = 1 - alpha;
 		break;
 
+	case FILTER_PEAKING_EQ:
+		b0 = 1 + alpha * A;
+		b1 = -2*cs;
+		b2 = 1 - alpha * A;
+		a0 = 1 + alpha / A;
+		// a1 = -2*cs;
+		a2 = 1 - alpha / A;
+		break;
+
+	case FILTER_LOW_SHELF:
+		b0 =      A * ((A + 1) - (A - 1)*cs + 2 * sqrt(A) * alpha);
+		b1 =  2 * A * ((A - 1) - (A + 1)*cs                      );
+		b2 =      A * ((A + 1) - (A - 1)*cs - 2 * sqrt(A) * alpha);
+		a0 =           (A + 1) + (A - 1)*cs + 2 * sqrt(A) * alpha ;
+		a1 =     -2 * ((A - 1) + (A + 1)*cs                      );
+		a2 =           (A + 1) + (A - 1)*cs - 2 * sqrt(A) * alpha ;
+		break;
+
+	case FILTER_HIGH_SHELF:
+		b0 =      A * ((A + 1) + (A - 1)*cs + 2 * sqrt(A) * alpha);
+		b1 = -2 * A * ((A - 1) + (A + 1)*cs                      );
+		b2 =      A * ((A + 1) + (A - 1)*cs - 2 * sqrt(A) * alpha);
+		a0 =           (A + 1) - (A - 1)*cs + 2 * sqrt(A) * alpha ;
+		a1 =      2 * ((A - 1) - (A + 1)*cs                      );
+		a2 =           (A + 1) - (A - 1)*cs - 2 * sqrt(A) * alpha ;
+		break;
+
 	default:
 		//unknown filter type
 		assert(false);
@@ -259,12 +291,12 @@ void StereoFilter::init(FilterType type, int new_order)
 	memset(feedback, 0, sizeof(feedback));
 #else
 	for (unsigned i = 0; i < 2; ++i) {
-		filters[i].init(type, 0, new_order, 0);
+		filters[i].init(type, new_order);
 	}
 #endif
 }
 
-void StereoFilter::render(float *inout_left_ptr, unsigned n_samples, float cutoff, float resonance)
+void StereoFilter::render(float *inout_left_ptr, unsigned n_samples, float cutoff, float resonance, float dbgain_normalized)
 {
 #ifdef __SSE__
 	if (parm_filter.filtertype == FILTER_NONE || parm_filter.filter_order == 0)
@@ -275,6 +307,7 @@ void StereoFilter::render(float *inout_left_ptr, unsigned n_samples, float cutof
 
 	parm_filter.set_linear_cutoff(cutoff);
 	parm_filter.set_resonance(resonance);
+	parm_filter.set_dbgain_normalized(dbgain_normalized);
 	parm_filter.update();
 
 	__m128 b0 = _mm_set1_ps(parm_filter.b0);
@@ -352,9 +385,9 @@ void StereoFilter::render(float *inout_left_ptr, unsigned n_samples, float cutof
   we need to raise the answer to the Nth power.
 
 */
-std::complex<double> Filter::evaluate_transfer_function(float omega)
+complex<double> Filter::evaluate_transfer_function(float omega)
 {
-	std::complex<float> z = exp(std::complex<float>(0.0f, omega));
-	std::complex<float> z2 = z * z;
-	return std::pow((b0 * z2 + b1 * z + b2) / (1.0f * z2 + a1 * z + a2), filter_order);
+	complex<float> z = exp(complex<float>(0.0f, omega));
+	complex<float> z2 = z * z;
+	return pow((b0 * z2 + b1 * z + b2) / (1.0f * z2 + a1 * z + a2), filter_order);
 }