From 805a0c4b975fba11ef9da8fa9e0d16a5ca3a8cd3 Mon Sep 17 00:00:00 2001
From: Vladislav Samsonov <vvladxx@gmail.com>
Date: Tue, 21 Jun 2016 14:35:52 +0300
Subject: [PATCH] Fixed build on VS

---
 modules/optflow/src/pcaflow.cpp | 8 ++++++++
 1 file changed, 8 insertions(+)

diff --git a/modules/optflow/src/pcaflow.cpp b/modules/optflow/src/pcaflow.cpp
index b118f763e..1ad00e99f 100644
--- a/modules/optflow/src/pcaflow.cpp
+++ b/modules/optflow/src/pcaflow.cpp
@@ -50,6 +50,14 @@ namespace optflow
 namespace
 {
 
+#ifndef M_PI
+const float M_PI = 3.14159265358979323846;
+#endif
+
+#ifndef M_SQRT2
+const float M_SQRT2 = 1.41421356237309504880;
+#endif
+
 template <typename T> inline int mathSign( T val ) { return ( T( 0 ) < val ) - ( val < T( 0 ) ); }
 
 /* Stable symmetric Householder reflection that gives c and s such that