joystick:

- only poll joysticks if we have an active joystick
- active joystick is defined as having callback and having positive (NON-ZERO!) pollInterval, as per GLUT sources
- use fgState.NumActiveJoysticks instead of fghHaveJoystick to save bunch of unnecessary function calls etc
- fghcbCheckJoystickPolls more concervative, per window we first check if a joystick is active (per above definition)

git-svn-id: https://svn.code.sf.net/p/freeglut/code/trunk@1554 7f0cb862-5218-0410-a997-914c9d46530a

freeglut/freeglut/src/fg_callbacks.c

@@ -213,13 +213,21 @@ void FGAPIENTRY glutJoystickFunc( FGCBJoystick callback, int pollInterval )
     FREEGLUT_EXIT_IF_NOT_INITIALISED ( "glutJoystickFunc" );
     fgInitialiseJoysticks ();
 
-    if ( ( ( fgStructure.CurrentWindow->State.JoystickPollRate < 0 ) ||
+    if ( (
-           !FETCH_WCB(*fgStructure.CurrentWindow,Joystick) ) &&  /* Joystick callback was disabled */
+           fgStructure.CurrentWindow->State.JoystickPollRate <= 0 ||        /* Joystick callback was disabled */
-         ( callback && ( pollInterval >= 0 ) ) )               /* but is now enabled */
+           !FETCH_WCB(*fgStructure.CurrentWindow,Joystick)
+         ) &&
+         ( 
+           callback && ( pollInterval > 0 )                                 /* but is now enabled */
+         ) )
         ++fgState.NumActiveJoysticks;
-    else if ( ( ( fgStructure.CurrentWindow->State.JoystickPollRate >= 0 ) &&
+    else if ( ( 
-                FETCH_WCB(*fgStructure.CurrentWindow,Joystick) ) &&  /* Joystick callback was enabled */
+                fgStructure.CurrentWindow->State.JoystickPollRate > 0 &&    /* Joystick callback was enabled */
-              ( !callback || ( pollInterval < 0 ) ) )              /* but is now disabled */
+                FETCH_WCB(*fgStructure.CurrentWindow,Joystick)
+              ) &&  
+              ( 
+                !callback || ( pollInterval <= 0 )                          /* but is now disabled */
+              ) )
         --fgState.NumActiveJoysticks;
 
     SET_CALLBACK( Joystick );

freeglut/freeglut/src/fg_internal.h

@@ -316,7 +316,7 @@ struct tagSFG_State
     fgExecutionState ExecState;           /* Used for GLUT termination       */
     char            *ProgramName;         /* Name of the invoking program    */
     GLboolean        JoysticksInitialised;  /* Only initialize if application calls for them */
-    int              NumActiveJoysticks;    /* Number of active joysticks -- if zero, don't poll joysticks */
+    int              NumActiveJoysticks;    /* Number of active joysticks (callback defined and positive pollrate) -- if zero, don't poll joysticks */
     GLboolean        InputDevsInitialised;  /* Only initialize if application calls for them */
 
 	int              MouseWheelTicks;      /* Number of ticks the mouse wheel has turned */

freeglut/freeglut/src/fg_main.c

@@ -172,7 +172,12 @@ static void fghDisplayAll( void )
 static void fghcbCheckJoystickPolls( SFG_Window *window,
                                      SFG_Enumerator *enumerator )
 {
-    fg_time_t checkTime = fgElapsedTime( );
+    fg_time_t checkTime;
+    
+    if (window->State.JoystickPollRate > 0 && FETCH_WCB( *window, Joystick ))
+    {
+        /* This window has a joystick to be polled (if pollrate <= 0, user needs to poll manually with glutForceJoystickFunc */
+        checkTime= fgElapsedTime( );
 
         if( window->State.JoystickLastPoll + window->State.JoystickPollRate <=
             checkTime )
@@ -182,12 +187,17 @@ static void fghcbCheckJoystickPolls( SFG_Window *window,
 #endif /* !defined(_WIN32_WCE) */
             window->State.JoystickLastPoll = checkTime;
         }
+    }
 
     fgEnumSubWindows( window, fghcbCheckJoystickPolls, enumerator );
 }
 
 /*
  * Check all windows for joystick polling
+ * 
+ * The real way to do this is to make use of the glutTimer() API
+ * to more cleanly re-implement the joystick API.  Then, this code
+ * and all other "joystick timer" code can be yanked.
  */
 static void fghCheckJoystickPolls( void )
 {
@@ -312,29 +322,8 @@ void fgWarning( const char *fmt, ... )
  * there is a joystick callback.  We have a short-circuit early
  * return if we find any joystick handler registered.
  *
- * The real way to do this is to make use of the glutTimer() API
- * to more cleanly re-implement the joystick API.  Then, this code
- * and all other "joystick timer" code can be yanked.
  *
  */
-static void fghCheckJoystickCallback( SFG_Window* w, SFG_Enumerator* e)
-{
-    if( FETCH_WCB( *w, Joystick ) )
-    {
-        e->found = GL_TRUE;
-        e->data = w;
-    }
-    fgEnumSubWindows( w, fghCheckJoystickCallback, e );
-}
-static int fghHaveJoystick( void )
-{
-    SFG_Enumerator enumerator;
-
-    enumerator.found = GL_FALSE;
-    enumerator.data = NULL;
-    fgEnumWindows( fghCheckJoystickCallback, &enumerator );
-    return !!enumerator.data;
-}
 static void fghHavePendingRedisplaysCallback( SFG_Window* w, SFG_Enumerator* e)
 {
     if( w->State.Redisplay && w->State.Visible )
@@ -353,6 +342,7 @@ static int fghHavePendingRedisplays (void)
     fgEnumWindows( fghHavePendingRedisplaysCallback, &enumerator );
     return !!enumerator.data;
 }
+
 /*
  * Returns the number of GLUT ticks (milliseconds) till the next timer event.
  */
@@ -378,9 +368,9 @@ static void fghSleepForEvents( void )
         return;
 
     msec = fghNextTimer( );
-    /* XXX Use GLUT timers for joysticks... */
+    /* XXX Should use GLUT timers for joysticks... */
     /* XXX Dumb; forces granularity to .01sec */
-    if( fghHaveJoystick( ) && ( msec > 10 ) )     
+    if( fgState.NumActiveJoysticks>0 && ( msec > 10 ) )     
         msec = 10;
 
 	fgPlatformSleepForEvents ( msec );
@@ -398,6 +388,7 @@ void FGAPIENTRY glutMainLoopEvent( void )
 
     if( fgState.Timers.First )
         fghCheckTimers( );
+    if (fgState.NumActiveJoysticks>0)   /* If zero, don't poll joysticks */
         fghCheckJoystickPolls( );
     fghDisplayAll( );