Engine directory for ticket #1

Engine/source/scene/zones/sceneTraversalState.h

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+//-----------------------------------------------------------------------------
+// Copyright (c) 2012 GarageGames, LLC
+//
+// Permission is hereby granted, free of charge, to any person obtaining a copy
+// of this software and associated documentation files (the "Software"), to
+// deal in the Software without restriction, including without limitation the
+// rights to use, copy, modify, merge, publish, distribute, sublicense, and/or
+// sell copies of the Software, and to permit persons to whom the Software is
+// furnished to do so, subject to the following conditions:
+//
+// The above copyright notice and this permission notice shall be included in
+// all copies or substantial portions of the Software.
+//
+// THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+// IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+// FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+// AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+// LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
+// FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS
+// IN THE SOFTWARE.
+//-----------------------------------------------------------------------------
+
+#ifndef _SCENETRAVERSALSTATE_H_
+#define _SCENETRAVERSALSTATE_H_
+
+#ifndef _TVECTOR_H_
+#include "core/util/tVector.h"
+#endif
+
+#ifndef _MBOX_H_
+#include "math/mBox.h"
+#endif
+
+#ifndef _MPLANESET_H_
+#include "math/mPlaneSet.h"
+#endif
+
+
+class SceneCullingState;
+class SceneCullingVolume;
+class SceneZoneSpace;
+
+
+/// Temporary state for zone traversals.  Keeps track of the zones
+/// that were visited in the current traversal chain as well as of
+/// the total area that so far has been visited in the traversal.
+class SceneTraversalState
+{
+   protected:
+
+      /// Scene culling state.
+      SceneCullingState* mCullingState;
+
+      /// Stack of zones visited in current traversal chain.
+      Vector< U32 > mZoneStack;
+
+      /// Stack of culling volumes.  Topmost is current volume.
+      Vector< SceneCullingVolume > mCullingVolumeStack;
+      
+      /// Area of scene visited in traversal.
+      Box3F mTraversedArea;
+
+   public:
+
+      /// Construct an empty scene traversal state.
+      /// @param cullingState Scene culling state.
+      SceneTraversalState( SceneCullingState* cullingState );
+
+      /// Return the scene culling state for this traversal.
+      SceneCullingState* getCullingState() const { return mCullingState; }
+
+      /// Get the scene area that has been visited so far in the traversal.
+      const Box3F& getTraversedArea() const { return mTraversedArea; }
+
+      /// Add an area to what has been visited so far in the traversal.
+      void addToTraversedArea( const Box3F& area ) { mTraversedArea.intersect( area ); }
+
+      /// @name Zone Stack
+      /// @{
+
+      /// Return the number of zones that are currently on the traversal stack.
+      U32 getTraversalDepth() const { return mZoneStack.size(); }
+
+      /// Push a zone onto the traversal stack.
+      void pushZone( U32 zoneId ) { mZoneStack.push_back( zoneId ); }
+
+      /// Pop the topmost zone from the traversal stack.
+      void popZone() { mZoneStack.pop_back(); }
+
+      /// Return true if the given zone has already been visited in the
+      /// current traversal chain, i.e. if it is currently on the traversal
+      /// stack.
+      bool haveVisitedZone( U32 zoneId ) const { return mZoneStack.contains( zoneId ); }
+
+      /// Return the zone ID of the topmost zone on the traversal stack.
+      U32 getZoneIdFromStack( U32 depth = 0 ) { return mZoneStack[ mZoneStack.size() - 1 - depth ]; }
+
+      /// Return the zone space that owns the topmost zone on the traversal stack.
+      SceneZoneSpace* getZoneFromStack( U32 depth = 0 );
+
+      /// @}
+
+      /// @name Culling Volume Stack
+      /// @{
+
+      /// Push a culling volume onto the stack so that it becomes the current culling
+      /// volume.
+      void pushCullingVolume( const SceneCullingVolume& volume );
+
+      /// Pop the current culling volume from the stack.
+      void popCullingVolume();
+
+      ///
+      const SceneCullingVolume& getCurrentCullingVolume() const { return mCullingVolumeStack.last(); }
+
+      /// @}
+};
+
+#endif // !_SCENETRAVERSALSTATE_H_