GridSectorizer.h

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#ifndef _GRID_SECTORIZER_H
#define _GRID_SECTORIZER_H

//#define _USE_ORDERED_LIST

#include "RakMemoryOverride.h"

#ifdef _USE_ORDERED_LIST
#include "DS_OrderedList.h"
#else
#include "DS_List.h"
#endif

class GridSectorizer
{
public:
        GridSectorizer();
        ~GridSectorizer();

        // _cellWidth, _cellHeight is the width and height of each cell in world units
        // minX, minY, maxX, maxY are the world dimensions (can be changed to dynamically allocate later if needed)
        void Init(const float _maxCellWidth, const float _maxCellHeight, const float minX, const float minY, const float maxX, const float maxY);

        // Adds a pointer to the grid with bounding rectangle dimensions
        void AddEntry(void *entry, const float minX, const float minY, const float maxX, const float maxY);

#ifdef _USE_ORDERED_LIST

        // Removes a pointer, as above
        void RemoveEntry(void *entry, const float minX, const float minY, const float maxX, const float maxY);

        // Adds and removes in one pass, more efficient than calling both functions consecutively
        void MoveEntry(void *entry, const float sourceMinX, const float sourceMinY, const float sourceMaxX, const float sourceMaxY,
                const float destMinX, const float destMinY, const float destMaxX, const float destMaxY);

#endif

        // Adds to intersectionList all entries in a certain radius
        void GetEntries(DataStructures::List<void*>& intersectionList, const float minX, const float minY, const float maxX, const float maxY);

        void Clear(void);

protected:
        int WorldToCellX(const float input) const;
        int WorldToCellY(const float input) const;
        int WorldToCellXOffsetAndClamped(const float input) const;
        int WorldToCellYOffsetAndClamped(const float input) const;

        // Returns true or false if a position crosses cells in the grid.  If false, you don't need to move entries
        bool PositionCrossesCells(const float originX, const float originY, const float destinationX, const float destinationY) const;

        float cellOriginX, cellOriginY;
        float cellWidth, cellHeight;
        float invCellWidth, invCellHeight;
        float gridWidth, gridHeight;
        int gridCellWidthCount, gridCellHeightCount;


        // int gridWidth, gridHeight;

#ifdef _USE_ORDERED_LIST
        DataStructures::OrderedList<void*, void*>* grid;
#else
        DataStructures::List<void*>* grid;
#endif
};

#endif