diff -Nurp p1/include/SDL_haptic.h p2/include/SDL_haptic.h
--- p1/include/SDL_haptic.h	2014-10-17 14:49:52.000000000 +0200
+++ p2/include/SDL_haptic.h	2014-10-17 15:51:56.000000000 +0200
@@ -558,7 +558,7 @@ typedef struct SDL_HapticPeriodic
     Uint16 period;      /**< Period of the wave. */
     Sint16 magnitude;   /**< Peak value; if negative, equivalent to 180 degrees extra phase shift. */
     Sint16 offset;      /**< Mean value of the wave. */
-    Uint16 phase;       /**< Horizontal shift given by hundredth of a degree. */
+    Uint16 phase;       /**< Positive phase shift given by hundredth of a degree. */
 
     /* Envelope */
     Uint16 attack_length;   /**< Duration of the attack. */