Some fixes for negative FramesPerSecond.

git-svn-id: svn://svn.code.sf.net/p/irrlicht/code/trunk@2328 dfc29bdd-3216-0410-991c-e03cc46cb475

source/Irrlicht/CAnimatedMeshSceneNode.cpp

@@ -78,7 +78,11 @@ void CAnimatedMeshSceneNode::setCurrentFrame(f32 frame)
 	// if you pass an out of range value, we just clamp it
 	CurrentFrameNr = core::clamp ( frame, (f32)StartFrame, (f32)EndFrame );
 
-	BeginFrameTime = os::Timer::getTime() - (s32)((CurrentFrameNr - StartFrame) / FramesPerSecond);
+	BeginFrameTime = os::Timer::getTime();
+	if (FramesPerSecond > 0)
+		BeginFrameTime += (s32)((CurrentFrameNr - StartFrame) / FramesPerSecond);
+	else if (FramesPerSecond < 0)
+		BeginFrameTime += (s32)((CurrentFrameNr - EndFrame) / -FramesPerSecond);
 
 	beginTransition(); //transit to this frame if enabled
 }
@@ -535,6 +539,9 @@ bool CAnimatedMeshSceneNode::setFrameLoop(s32 begin, s32 end)
 		StartFrame = core::s32_clamp(begin, 0, maxFrameCount);
 		EndFrame = core::s32_clamp(end, StartFrame, maxFrameCount);
 	}
+	if (FramesPerSecond < 0)
+		setCurrentFrame ( (f32)EndFrame );
+	else
 		setCurrentFrame ( (f32)StartFrame );
 
 	return true;