From 28539c8e95d080bdb213c8a82f29d0fbb43712bc Mon Sep 17 00:00:00 2001
From: dcnieho <dcnieho@7f0cb862-5218-0410-a997-914c9d46530a>
Date: Sun, 7 Apr 2013 08:03:48 +0000
Subject: [PATCH] doc that timers are sorted by endtime + don't call
 fgElapsedTime() if no timers to check, its a waste

git-svn-id: https://svn.code.sf.net/p/freeglut/code/trunk@1613 7f0cb862-5218-0410-a997-914c9d46530a
---
 freeglut/freeglut/src/fg_callbacks.c | 1 +
 freeglut/freeglut/src/fg_main.c      | 7 ++++---
 2 files changed, 5 insertions(+), 3 deletions(-)

diff --git a/freeglut/freeglut/src/fg_callbacks.c b/freeglut/freeglut/src/fg_callbacks.c
index 7c82c81..768358b 100644
--- a/freeglut/freeglut/src/fg_callbacks.c
+++ b/freeglut/freeglut/src/fg_callbacks.c
@@ -63,6 +63,7 @@ void FGAPIENTRY glutTimerFunc( unsigned int timeOut, FGCBTimer callback, int tim
     timer->ID        = timerID;
     timer->TriggerTime = fgElapsedTime() + timeOut;
 
+    /* Insert such that timers are sorted by end-time */
     for( node = fgState.Timers.First; node; node = node->Node.Next )
     {
         if( node->TriggerTime > timer->TriggerTime )
diff --git a/freeglut/freeglut/src/fg_main.c b/freeglut/freeglut/src/fg_main.c
index d2108e7..39fecd4 100644
--- a/freeglut/freeglut/src/fg_main.c
+++ b/freeglut/freeglut/src/fg_main.c
@@ -261,7 +261,7 @@ static void fghCheckTimers( void )
         SFG_Timer *timer = fgState.Timers.First;
 
         if( timer->TriggerTime > checkTime )
-            /* XXX: are timers always sorted by triggerTime? If not, this and fghNextTimer are wrong */
+            /* Timers are sorted by triggerTime */
             break;
 
         fgListRemove( &fgState.Timers, &timer->Node );
@@ -388,12 +388,13 @@ static int fghHavePendingRedisplays (void)
  */
 static fg_time_t fghNextTimer( void )
 {
-    fg_time_t currentTime = fgElapsedTime();
-    SFG_Timer *timer = fgState.Timers.First;
+    fg_time_t currentTime;
+    SFG_Timer *timer = fgState.Timers.First;    /* timers are sorted by trigger time, so only have to check the first */
 
     if( !timer )
         return INT_MAX;
 
+    currentTime = fgElapsedTime();
     if( timer->TriggerTime < currentTime )
         return 0;
     else