Engine directory for ticket #1

Engine/source/terrain/terrCell.h

@@ -0,0 +1,248 @@
+//-----------------------------------------------------------------------------
+// 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 _TERRCELL_H_
+#define _TERRCELL_H_
+
+#ifndef _GFXVERTEXBUFFER_H_
+#include "gfx/gfxVertexBuffer.h"
+#endif
+#ifndef _GFXPRIMITIVEBUFFER_H_
+#include "gfx/gfxPrimitiveBuffer.h"
+#endif
+#ifndef _TDICTIONARY_H_
+#include "core/util/tDictionary.h"
+#endif
+#ifndef _MORIENTEDBOX_H_
+#include "math/mOrientedBox.h"
+#endif
+#ifndef _BITVECTOR_H_
+#include "core/bitVector.h"
+#endif
+
+class TerrainBlock;
+class TerrainCellMaterial;
+class Frustum;
+class SceneRenderState;
+class SceneZoneSpaceManager;
+
+
+/// The TerrainCell vertex format optimized to
+/// 32 bytes for optimal vertex cache performance.
+GFXDeclareVertexFormat( TerrVertex )
+{
+   /// The position.
+   Point3F point;
+
+   /// The normal.
+   Point3F normal;
+
+   /// The height for calculating the
+   /// tangent vector on the GPU.
+   F32 tangentZ;
+
+   /// The empty flag state which is either 
+   /// -1 or 1 so we can do the special 
+   /// interpolation trick.
+   F32 empty;
+};
+
+
+/// The TerrCell is a single quadrant of the terrain geometry quadtree.
+class TerrCell
+{
+protected:
+
+   /// The handle to the static vertex buffer which holds the 
+   /// vertices for this cell.
+   GFXVertexBufferHandle<TerrVertex> mVertexBuffer;
+
+   /// The handle to the static primitive buffer for this cell.
+   /// It is only used if this cell has any empty squares
+   GFXPrimitiveBufferHandle mPrimBuffer;
+
+   ///
+   Point2I mPoint;
+   
+   ///
+   U32 mSize;
+
+   /// The level of this cell within the quadtree (of cells) where
+   /// zero is the root and one is a direct child of the root, etc.
+   U32 mLevel;
+
+   /// Statics used in VB and PB generation.   
+   static const U32 smVBStride;
+   static const U32 smMinCellSize;
+   static const U32 smVBSize;
+   static const U32 smPBSize;
+   static const U32 smTriCount;
+
+   /// Triangle count for our own primitive buffer, if any
+   U32 mTriCount;
+
+   /// Indicates if this cell has any empty squares
+   bool mHasEmpty;
+
+   /// A list of all empty vertices for this cell
+   Vector<U32> mEmptyVertexList;
+
+   /// The terrain this cell is based on.
+   TerrainBlock *mTerrain;
+
+   /// The material used to render the cell.
+   TerrainCellMaterial *mMaterial;
+
+   /// The bounding box of this cell in 
+   /// TerrainBlock object space.
+   Box3F mBounds;
+
+   /// The OBB of this cell in world space.
+   OrientedBox3F mOBB;
+
+   /// The bounding radius of this cell.
+   F32 mRadius;
+
+   /// The child cells of this one.
+   TerrCell *mChildren[4];
+
+   /// This bit flag tells us which materials effect
+   /// this cell and is used for optimizing rendering.
+   /// @see TerrainFile::mMaterialAlphaMap
+   U64 mMaterials;
+
+   /// Whether this cell is fully contained inside interior zones.
+   bool mIsInteriorOnly;
+
+   /// The zone overlap for this cell.
+   /// @note The bit for the outdoor zone is never set.
+   BitVector mZoneOverlap;
+
+   ///
+   void _updateBounds();
+
+   /// Update #mOBB from the current terrain transform state.
+   void _updateOBB();
+
+   //
+   void _init( TerrainBlock *terrain,
+               const Point2I &point,
+               U32 size,
+               U32 level );
+
+   // 
+   void _updateVertexBuffer();
+
+   //
+   void _updatePrimitiveBuffer();
+
+   // 
+   void _updateMaterials();
+
+   //
+   bool _isVertIndexEmpty( U32 index ) const;
+
+public:
+
+   TerrCell();
+   virtual ~TerrCell();
+
+   static TerrCell* init( TerrainBlock *terrain );
+
+   void getRenderPrimitive(   GFXPrimitive *prim,
+                              GFXVertexBufferHandleBase *vertBuff,
+                              GFXPrimitiveBufferHandle  *primBuff ) const;
+
+   void updateGrid( const RectI &gridRect, bool opacityOnly = false );
+
+   /// Update the world-space OBBs used for culling.
+   void updateOBBs();
+
+   ///
+   void updateZoning( const SceneZoneSpaceManager *zoneManager );
+
+   void cullCells( const SceneRenderState *state,
+                   const Point3F &objLodPos,
+                   Vector<TerrCell*> *outCells );
+
+   const Box3F& getBounds() const { return mBounds; }
+
+   /// Returns the object space sphere bounds.
+   SphereF getSphereBounds() const { return SphereF( mBounds.getCenter(), mRadius ); }
+
+   F32 getSqDistanceTo( const Point3F &pt ) const;
+
+   F32 getDistanceTo( const Point3F &pt ) const;
+
+   U64 getMaterials() const { return mMaterials; }
+
+   /// Returns a bit vector of what zones overlap this cell.
+   const BitVector& getZoneOverlap() const { return mZoneOverlap; }
+   
+   /// Forces the loading of the materials for this
+   /// cell and all its child cells.
+   void preloadMaterials();
+
+   TerrainCellMaterial* getMaterial();
+
+   /// Return true if this is a leaf cell, i.e. a cell without children.
+   bool isLeaf() const { return !mChildren[ 0 ]; }
+
+   /// Deletes the materials for this cell 
+   /// and all its children.  They will be
+   /// recreate on the next request.
+   void deleteMaterials();
+
+   U32 getSize() const { return mSize; }
+
+   Point2I getPoint() const { return mPoint; }   
+
+   /// Initializes a primitive buffer for rendering any cell.
+   static void createPrimBuffer( GFXPrimitiveBufferHandle *primBuffer );
+
+   /// Debug Rendering
+   /// @{
+
+   /// Renders the debug bounds for this cell.
+   void renderBounds() const;
+
+   /// @}
+};
+
+inline F32 TerrCell::getDistanceTo( const Point3F &pt ) const
+{
+   return ( mBounds.getCenter() - pt ).len() - mRadius;
+}
+
+inline bool TerrCell::_isVertIndexEmpty( U32 index ) const
+{
+   for ( U32 i = 0; i < mEmptyVertexList.size(); ++i )
+   {
+      if ( mEmptyVertexList[i] == index )
+      {
+         return true;
+      }
+   }
+   return false;
+}
+
+#endif // _TERRCELL_H_