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diff --git a/Opcode/OPC_PlanesAABBOverlap.h b/Opcode/OPC_PlanesAABBOverlap.h
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+///////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////
+/**
+ *	Planes-AABB overlap test.
+ *	- original code by Ville Miettinen, from Umbra/dPVS (released on the GD-Algorithms mailing list)
+ *	- almost used "as-is", I even left the comments (hence the frustum-related notes)
+ *
+ *	\param		center			[in] box center
+ *	\param		extents			[in] box extents
+ *	\param		out_clip_mask	[out] bitmask for active planes
+ *	\param		in_clip_mask	[in] bitmask for active planes
+ *	\return		TRUE if boxes overlap planes
+ */
+///////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////
+inline_ BOOL PlanesCollider::PlanesAABBOverlap(const IcePoint& center, const IcePoint& extents, udword& out_clip_mask, udword in_clip_mask)
+{
+	// Stats
+	mNbVolumeBVTests++;
+
+	const Plane* p = mPlanes;
+
+	// Evaluate through all active frustum planes. We determine the relation 
+	// between the AABB and a plane by using the concept of "near" and "far"
+	// vertices originally described by Zhang (and later by Möller). Our
+	// variant here uses 3 fabs ops, 6 muls, 7 adds and two floating IcePoint
+	// comparisons per plane. The routine early-exits if the AABB is found
+	// to be outside any of the planes. The loop also constructs a new output
+	// clip mask. Most FPUs have a native single-cycle fabsf() operation.
+
+	udword Mask				= 1;			// current mask index (1,2,4,8,..)
+	udword TmpOutClipMask	= 0;			// initialize output clip mask into empty. 
+
+	while(Mask<=in_clip_mask)				// keep looping while we have active planes left...
+	{
+		if(in_clip_mask & Mask)				// if clip plane is active, process it..
+		{               
+			float NP = extents.x*fabsf(p->n.x) + extents.y*fabsf(p->n.y) + extents.z*fabsf(p->n.z);	// ### fabsf could be precomputed
+			float MP = center.x*p->n.x + center.y*p->n.y + center.z*p->n.z + p->d;
+
+			if(NP < MP)						// near vertex behind the clip plane... 
+				return FALSE;				// .. so there is no intersection..
+			if((-NP) < MP)					// near and far vertices on different sides of plane..
+				TmpOutClipMask |= Mask;		// .. so update the clip mask...
+		}
+		Mask+=Mask;							// mk = (1<<plane)
+		p++;								// advance to next plane
+	}
+
+	out_clip_mask = TmpOutClipMask;			// copy output value (temp used to resolve aliasing!)
+	return TRUE;							// indicate that AABB intersects frustum
+}