Add M_PI which isn't defined by gcc with std=c++11.

diff --git a/src/lib/util.h b/src/lib/util.h
index d4616a7c9ea1bc4e0eadcb7e413a721314917602..1d4b013581870c97184eff2b11453766a205c97a 100644 (file)
--- a/src/lib/util.h
+++ b/src/lib/util.h
@@ -43,6 +43,10 @@ namespace dcp {
        class SoundAsset;
 }
 
+#ifndef M_PI
+#define M_PI (3.14159265358979323846)
+#endif
+
 /** The maximum number of audio channels that we can have in a DCP */
 #define MAX_DCP_AUDIO_CHANNELS 16
 /** Message broadcast to find possible encoding servers */