/************************** 
	ROcclusion Header file
	Info : Horizon Occlusion Culling's Header
	
	: 대일형 list 이용안한 버젼 입니다.
	: CheckCulling 안에 리스트를 넣어주시면 됩니다. 
	: list의 형은 ROcclusionUnit이고 m_Cube 변수만 채워 주시면 되요.

************************* */

#ifndef __ROCCLUSION_H__
#define __ROCCLUSION_H__
#include <d3dx8.h>
#include <d3d8.h>
#include "RCube.h"


#define INIT_HEIGHT 10000.0f
const float FAIL = -32767.0f;

// Sorting 용 global Function
int OcclusionHCompare( const void *arg1, const void *arg2 );		// Horizon Culling 용	

class ROcclusionUnit												//Horizon 용
{
protected:
	class ROcclusionBox												//projected Screen 2D Box 
	{
	public:
		D3DXVECTOR2					m_vecMin;
		D3DXVECTOR2					m_vecMax;
		D3DXVECTOR3					m_vecCenter;
		float						m_fZValue;						//camera space 에서의 Z Value
		

		ROcclusionBox() 
		{
		
			m_vecMin = D3DXVECTOR2(0.0f,0.0f);
			m_vecMax = D3DXVECTOR2(0.0f,0.0f);
			m_vecCenter = D3DXVECTOR3(10000.0f,10000.0f,10000.0f);
			m_fZValue = 0.0f;

		}
		~ROcclusionBox() {}
		
		//box 안에 있는지 검사
		bool ROcclusionInBox(ROcclusionBox tb) 
		{
			if( ( m_vecMin.x <= tb.m_vecMin.x ) && ( m_vecMin.y <= tb.m_vecMin.y ) && 
				( m_vecMax.x >= tb.m_vecMax.x ) && ( m_vecMax.y >= tb.m_vecMax.y ) )
				return true;
			
			return false;

		}
	};
	void CreateOccBox(D3DXVECTOR3 min,D3DXVECTOR3 max,D3DXVECTOR3 center,bool projected = false);
	void FindPoint(D3DXVECTOR3 *);

public:
	ROcclusionUnit() 
	{
		m_bVis = NULL;
		if(m_bVis != NULL)( *m_bVis ) = true;
	
	}
	~ROcclusionUnit() {}

	void Create(LPDIRECT3DDEVICE8 device);
	
	RCube					m_Cube;					// Cube Data
	ROcclusionBox			m_OccBox;				// 2D Projection Box
	bool					*m_bVis;	
	
	LPDIRECT3DDEVICE8 m_Device;
	
};

class ROcclusionVolume								// Occlusion Volume
{
public:
	float					m_Height;
	ROcclusionVolume() 
	{
		m_Height = INIT_HEIGHT;
	}
};

class ROcclusion 
{
public:
	
	ROcclusion()
	{
		m_Volume = NULL;
		m_VWidth = 0;
		m_VHeight = 0;
		m_ViewObject = -1;
		m_HidenObject = -1;

	}
	~ROcclusion()
	{
		if( m_Volume )
			delete[] m_Volume;
	}

	static void CheckCulling( LPDIRECT3DDEVICE8 ,ROcclusionUnit *,int num,float camera_x,float camera_y,float camera_z );
	static void SortList( ROcclusionUnit *,int num,float camerax,float cameray,float cameraz,LPDIRECT3DDEVICE8 );

	
	//Horizon occlusion culling  
	static void Hculling( ROcclusionUnit *list,int listnum,int start_index,float ,float ,float );
	static void HorizonCull( LPDIRECT3DDEVICE8 ,ROcclusionUnit *,int listnum );
	static void InitVolume();

	static ROcclusionVolume		*m_Volume;
	// Screen Width, Height
	static unsigned long		m_VWidth;
	static unsigned long		m_VHeight;
	
	//occlusion info
	static int					m_ViewObject;
	static int					m_HidenObject;


};

#endif