/*==========================================================================
 *	(C) 2005 Universidad Jaime I de Castellón
 *==========================================================================
 *	PROYECT:	GAME TOOLS
 *==========================================================================*/
/*	CONTENT:
 *
 *
 *	@file	GeoLodStripsLibrary.h
 *==========================================================================*/

#ifndef _GEOLODSTRIPSLIBRARY
#define _GEOLODSTRIPSLIBRARY

#include	"GeoMesh.h"
#include	<vector>
#include	"VertexData.h"
#include "GeoLodObject.h"

namespace Geometry
{
	//typedef unsigned long int SmallInt;
	typedef unsigned long SmallInt;
	typedef unsigned long	ULong;
	typedef	long					Long;
	
	typedef struct
	{
		SmallInt strip;
		SmallInt position;
		SmallInt rep; //For the vertex repetition
	} PositionType;

	typedef	struct
	{
		unsigned	long	strip; // change this to uint32
		char						position;
		char						vertexRepetition;
		char						edgeRepetition;
		char						obligatory;
	}	LODRegisterType;

	typedef struct
	{
		float		Vertex[3];
		SmallInt	Next;
	} VertexType;

	typedef std::vector	<SmallInt>				SmallIntVector;
	typedef	std::vector	<LODRegisterType>	LODRegisterVector;
	typedef	std::vector	<Long>						LongVector;


	class LodStripsLibraryData
	{
		public:

			SmallIntVector								mFileVertices;
			std::vector	<LODRegisterType>	mFileChangesLOD;
			LongVector										mData;
			std::vector<unsigned int>			p_changes;
	};

	/// The LodStripsLibrary interface class.
	/** This module contains functions that handle the levels of detail 
	 * 	of the input multiresolution objects made of polygonal meshes.
	 * 	For any given resolution and object, this module returns a set
	 * 	of triangle strips representing the object at that resolution, 
	 * 	that is, at the level of detail requested. These models use 
	 * 	triangle strips to reduce storage usage and to speed up realistic 
	 * 	rendering. */

	class GEOLODLIBRARYDLL_API LodStripsLibrary : public Geometry::LodObject
	{
		private:
			
			// The name of the object.
			String	mName; 

			//	Structures with the data read from the file
			//	We won't work with these structures
			SmallIntVector								mFileVertices;
			std::vector	<LODRegisterType>	mFileChangesLOD;
			std::vector	<SmallIntVector>	mFileStrips;
			LongVector										mData;

			//	Structures with the data to work with

			//	Total strips of the multiresolution object.
			SmallInt	mTotalStrips;
			
			//	Total vertices of the multiresolution object.
			SmallInt	mTotalVertices;
			
			//	Number of vertices of the max LOD.
			SmallInt	mMaxVerticesLOD;
			
			//	Total changes of the multiresolution object.
			SmallInt	mTotalChanges;
			
			SmallInt	mLods;				//	Available Lods.
			SmallInt	mMaxLod;			//	Max level of detail.
			SmallInt	mMinLod;			//	Min level of detail.
			SmallInt	mCurrentLod;	//	Current Lod.

			//	For the efficient version.
			SmallInt				mTotalFaces;
			SmallInt				*mCurrentData;
			SmallInt				*mStripsChanges;
			LODRegisterType	*mCurrentRegLOD;
			SmallInt				*mVertex;

			SmallInt	minFaces, maxFaces;
		
			//	Changes of Strips in LOD file (p).
			SmallInt	*mPChanges;

			///Total of vertices shown at the moment.
			long	int	mTotal;

			//	Global mesh object.
			Mesh	*mGeoMesh;

			//	Copa STL vectors to C arrays.
			void	CopyVectors2Arrays(void);

			//	Loads Mesh.
			void	LoadStripMesh(const LodStripsLibraryData *, Mesh *geomesh);

			//	Strips vector.
			SmallIntVector	*mStrips;

			int	*indices_x_submesh;
			int *offsets_x_submesh;

			void UpdateDataRetrievalInterface(void);

			//Number of strips in each submesh
			int		*mStripsSubmesh;
			bool	delete_indexdata;
			int		*submesh_x_strip;
			Real	lodFactor;

			IndexData	*dataRetrievalInterface;
			uint32		current_triangle_count;

		public:

			/// Class constructor
			/**	Constructs a LodStrips multiresolution object from:
				- The LodStrips decimation information (this can be obtained using the class Geometry::MeshLoader)
				- The Mesh object defining the geometry of the model at its full level of detail (this can be obtained using the class Geometry::MeshLoader)
				- a user-defined Geometry::IndexData instance
			*/
			LodStripsLibrary(const	LodStripsLibraryData *,
							 Mesh	*geomesh,
							 IndexData	*userindexdata);

			/// Class destructor.
			~LodStripsLibrary(void);

			/// changes the level of detail of the object to a specified factor
			/** The value specified to chane the LOD must be in the range [0,1] ([min,max])
				After the LOD is calculated, this function automatically updates the indices
				using the IndexData interface provided in the constructor.*/			
			virtual void GoToLod(Real);

			/// Returns the number of triangles of the highest LOD.
			uint32	MaxFaces() const;

			/// Returns the number of triangles of the lowest LOD.
			uint32	MinFaces() const;

			/// Returns the index count at the current LOD of a certain submesh
			uint32 GetValidIndexCount(int submeshid)	const
			{
				return indices_x_submesh[submeshid];
			}

			/// Retrieves the total number of strips of all submeshes
			uint32 GetTotalStripCount(void)	const
			{
				return mTotalStrips;
			}

			/// Returns the number of strips of a given submesh
			uint32 GetSubMeshtripCount(int submeshid)	const
			{
				return mStripsSubmesh[submeshid];
			}

			/// Gets the triangle count at the current LOD
			uint32 GetCurrentTriangleCount(void)	const
			{
				return current_triangle_count;
			}

			/// Gets the current LOD factos
			virtual Real GetCurrentLodFactor(void)	const
			{
				return lodFactor;
			}

			// Retrieves the IndexData index interface
			Geometry::IndexData *GetIndexDataInterface(void) const
			{
				return dataRetrievalInterface;
			}

			// deprecated functions
//			void	TrimByLod(uint32, uint32);
/*			uint32	MaxVertices();
			uint32	MinVertices();*/
	};
}

#endif