source: trunk/VUT/GtpVisibilityPreprocessor/src/ViewCell.h @ 419

#ifndef _ViewCell_H__
#define _ViewCell_H__

#include "Mesh.h"
#include "Containers.h"
#include "Ray.h"

//namespace GtpVisibilityPreprocessor {
  
class BspInterior;
class BspPvs;
struct Triangle3;
class BspLeaf;

/**
        View cell with an optional mesh representation
*/
class ViewCell: public MeshInstance
{
public:
        ViewCell();
        /** Constructor taking a mesh representing the shape of the viewcell.
        */
        ViewCell(Mesh *mesh);
        /** Returns Pvs. 
        */
        const ViewCellPvs &GetPvs() const;
        ViewCellPvs &GetPvs();

        int Type() const;

        /** Derives viewcells from object container.
                @param objects the intersectables the viewcells are derived from
                @param viewCells the viewcells are returned in this container
                @param maxViewCells the maximum number of viewcells created. if 0 => unbounded
        */
        static void DeriveViewCells(const ObjectContainer &objects, 
                                                                ViewCellContainer &viewCells, 
                                                                const int maxViewCells);

        
        /** Adds a passing ray to the passing ray container.
        */
        void AddPassingRay(const Ray &ray, const int contributions);    

        /** Constructs view cell from base triangle. The ViewCell is extruded along the normal vector.
                @param the base triangle
                @param the height of the newly created view cell
        */
        static ViewCell *ExtrudeViewCell(const Triangle3 &baseTri, const float height);

        /** Merges two view cells.
                @note the piercing rays of the front and back will be ordered   
                @returns new view cell based on the merging.
        */
        static ViewCell *Merge(ViewCell &front, ViewCell &back);

        /// Ray set description of the rays passing through this node.  
        PassingRaySet mPassingRays;

        /// Rays piercing this view cell.
        RayContainer mPiercingRays;

        /// view cells types
        enum HierarchyType {BSP, KD, VSP};

        /** Generates view cells of type specified by view cells type.
        */
        static ViewCell *Generate(Mesh *mesh = NULL);

        /// type of view cells hierarchy (KD, BSP)
        static HierarchyType sHierarchy;

protected:

        /// the potentially visible objects
        ViewCellPvs mPvs;
};

class BspViewCell: public ViewCell
{
public:
        BspViewCell(): mBspLeaves(0) {}
        BspViewCell(Mesh *mesh): 
        ViewCell(mesh), mBspLeaves(0) {}

        /// Leaves which hold this view cell.
        vector<BspLeaf *> mBspLeaves;
};

#endif