From 4ade726a07e11997e6bfc216186d11334790eb6a Mon Sep 17 00:00:00 2001
From: Siana Gearz <siana.sg@live.de>
Date: Mon, 10 Sep 2012 16:31:27 +0200
Subject: [PATCH] Fix PATH-842 rotation reset on object update

---
 indra/newview/llviewerobject.cpp | 20 +++++++++++++++-----
 indra/newview/llviewerobject.h   |  1 +
 2 files changed, 16 insertions(+), 5 deletions(-)

diff --git a/indra/newview/llviewerobject.cpp b/indra/newview/llviewerobject.cpp
index 186e7d57b..b8833d302 100644
--- a/indra/newview/llviewerobject.cpp
+++ b/indra/newview/llviewerobject.cpp
@@ -241,6 +241,7 @@ LLViewerObject::LLViewerObject(const LLUUID &id, const LLPCode pcode, LLViewerRe
 	mNumFaces(0),
 	mTimeDilation(1.f),
 	mRotTime(0.f),
+	mAngularVelocityRot(),
 	mState(0),
 	mMedia(NULL),
 	mClickAction(0),
@@ -270,6 +271,7 @@ LLViewerObject::LLViewerObject(const LLUUID &id, const LLPCode pcode, LLViewerRe
 	{
 		mPositionAgent = mRegionp->getOriginAgent();
 	}
+	resetRot();
 
 	LLViewerObject::sNumObjects++;
 }
@@ -2105,14 +2107,14 @@ U32 LLViewerObject::processUpdateMessage(LLMessageSystem *mesgsys,
 	if (new_rot != getRotation()
 		|| new_angv != old_angv)
 	{
-		if (new_rot != getRotation())
+		if (new_angv != old_angv)
 		{
-			setRotation(new_rot);
+			resetRot();
 		}
-		
+
+		// Set the rotation of the object followed by adjusting for the accumulated angular velocity (llSetTargetOmega)
+		setRotation(new_rot * mAngularVelocityRot);
 		setChanged(ROTATED | SILHOUETTE);
-		
-		resetRot();
 	}
 
 
@@ -5498,8 +5500,13 @@ void LLViewerObject::applyAngularVelocity(F32 dt)
 
 		ang_vel *= 1.f/omega;
 		
+		// calculate the delta increment based on the object's angular velocity
 		dQ.setQuat(angle, ang_vel);
+
+		// accumulate the angular velocity rotations to re-apply in the case of an object update
+		mAngularVelocityRot *= dQ;
 		
+		// Just apply the delta increment to the current rotation
 		setRotation(getRotation()*dQ);
 		setChanged(MOVED | SILHOUETTE);
 	}
@@ -5508,6 +5515,9 @@ void LLViewerObject::applyAngularVelocity(F32 dt)
 void LLViewerObject::resetRot()
 {
 	mRotTime = 0.0f;
+
+	// Reset the accumulated angular velocity rotation
+	mAngularVelocityRot.loadIdentity(); 
 }
 
 U32 LLViewerObject::getPartitionType() const
diff --git a/indra/newview/llviewerobject.h b/indra/newview/llviewerobject.h
index 2b9597510..791393533 100644
--- a/indra/newview/llviewerobject.h
+++ b/indra/newview/llviewerobject.h
@@ -736,6 +736,7 @@ protected:
 
 	F32				mTimeDilation;				// Time dilation sent with the object.
 	F32				mRotTime;					// Amount (in seconds) that object has rotated according to angular velocity (llSetTargetOmega)
+	LLQuaternion	mAngularVelocityRot;		// accumulated rotation from the angular velocity computations
 
 	U8				mState;	// legacy
 	LLViewerObjectMedia* mMedia;	// NULL if no media associated