From d79392ecf3f611cf10476d9dabdf39d91097ad00 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?=D0=91=D1=8B=D1=87=D0=BA=D0=BE=D0=B2=20=D0=90=D0=BD=D0=B4?=
 =?UTF-8?q?=D1=80=D0=B5=D0=B9?= <andrey@signalmodelling.ru>
Date: Fri, 31 Mar 2017 15:58:45 +0000
Subject: [PATCH] git-svn-id: svn://db.shs.com.ru/pip@326
 12ceb7fc-bf1f-11e4-8940-5bc7170c53b5

---
 CMakeLists.txt   | 11 +++++++++
 src/math/pifft.h | 60 ++++++++++++++++++++++++++++++++++++++++++++++++
 2 files changed, 71 insertions(+)

diff --git a/CMakeLists.txt b/CMakeLists.txt
index c6e8eb60..9a057cae 100644
--- a/CMakeLists.txt
+++ b/CMakeLists.txt
@@ -35,6 +35,7 @@ option(ICU "Unicode support" 1)
 option(USB "USB support" 0)
 option(STL "Building with STL containers" 0)
 option(CRYPT "Crypt support" 0)
+option(FFTW "fftw3 support for PIFFT" 1)
 option(INTROSPECTION_CONTAINERS "Build with containers introspection" 0)
 option(INTROSPECTION_THREADS "Build with threads introspection" 0)
 option(LIB "System install" 1)
@@ -142,6 +143,16 @@ else ()
 endif ()
 
 
+# Check if PIP support fftw3 for PIFFT using in math module
+if (FFTW)
+	message(STATUS "Building with fftw3 support")
+	set(CMAKE_CXX_FLAGS "${CMAKE_CXX_FLAGS} -DPIP_FFTW")
+	list(APPEND LIBS fftw3-3 fftw3f-3 fftw3l-3)
+else ()
+	message(STATUS "Building without fftw3 support")
+endif ()
+
+
 # Check if PIP should be built with containers introspection
 if (INTROSPECTION_CONTAINERS)
 	message(STATUS "Building with containers introspection")
diff --git a/src/math/pifft.h b/src/math/pifft.h
index 3e91b40a..acf1ae33 100644
--- a/src/math/pifft.h
+++ b/src/math/pifft.h
@@ -121,4 +121,64 @@ typedef PIFFT_double PIFFT;
 typedef PIFFT_double PIFFTd;
 typedef PIFFT_float PIFFTf;
 
+
+
+// fftw3 realisation
+#ifdef PIP_FFTW
+#include <complex.h>
+#include "fftw3.h"
+
+template <typename T>
+class PIP_EXPORT PIFFTW
+{
+public:
+	const PIVector<complex<T> > & calcFFT(const PIVector<complex<T> > &in) {
+		result.resize(in.size());
+		p = fftw_plan_dft_1d(in.size_s(), (fftw_complex *)in.data(), (fftw_complex *)result.data(), FFTW_FORWARD, FFTW_ESTIMATE);
+		fftw_execute(p);
+		fftw_destroy_plan(p);
+		return result;
+	}
+	const PIVector<complex<T> > & calcFFT(const PIVector<T> &in) {
+		result.resize(in.size());
+		p = fftw_plan_dft_r2c_1d(in.size_s(), (double *)in.data(), (fftw_complex *)result.data(), FFTW_ESTIMATE);
+		fftw_execute(p);
+		fftw_destroy_plan(p);
+		return result;
+	}
+	const PIVector<complex<T> > & calcFFTinverse(const PIVector<complex<T> > &in) {
+		result.resize(in.size());
+		p = fftw_plan_dft_1d(in.size_s(), (fftw_complex *)in.data(), (fftw_complex *)result.data(), FFTW_BACKWARD, FFTW_ESTIMATE);
+		fftw_execute(p);
+		fftw_destroy_plan(p);
+		return result;
+	}
+
+	enum FFT_Operation {fo_real, fo_complex, fo_inverse};
+
+	void preparePlan(int size, FFT_Operation op) {
+		PIVector<complex<T> > in(size), out(size);
+		PIVector<T> inr(size);
+		switch (op) {
+			case fo_real:
+				p = fftw_plan_dft_r2c_1d(in.size_s(), (double *)inr.data(), (fftw_complex *)out.data(), FFTW_MEASURE);
+			break;
+			case fo_complex:
+				p = fftw_plan_dft_1d(in.size_s(), (fftw_complex *)in.data(), (fftw_complex *)out.data(), FFTW_FORWARD, FFTW_MEASURE);
+			break;
+			case fo_inverse:
+				p = fftw_plan_dft_1d(in.size_s(), (fftw_complex *)in.data(), (fftw_complex *)out.data(), FFTW_BACKWARD, FFTW_MEASURE);
+			break;
+		}
+	}
+
+private:
+	PIVector<complex<T> > result;
+	fftw_plan p;
+};
+
+typedef PIFFTW<double> PIFFTWd;
+
+#endif // PIP_FFTW
+
 #endif // PIFFT_H