glfrustum.h

体现了lod(level of detail)算法 包括网格细分,空间层次

// Frustum.h: Interface of the class CFrustum.
//
//////////////////////////////////////////////////////////////////////

#if !defined(AFX_FRUSTRUM_H__CA0D0C57_056C_44F8_8AFD_AFDE66FD2451__INCLUDED_)
#define AFX_FRUSTRUM_H__CA0D0C57_056C_44F8_8AFD_AFDE66FD2451__INCLUDED_

#if _MSC_VER > 1000
#pragma once
#endif // _MSC_VER > 1000

///////////////////////////////////////////////////////////
// For more informations on frustum culling visit       //
// http://www.markmorley.com/opengl/frustumculling.html  //
// This class is based on the this tutorial and its code //
///////////////////////////////////////////////////////////

#include <windows.h>
#include <math.h>
#include <stdio.h>
#include <math.h>
#include <gl/gl.h>
#include <gl/glu.h>

//#include "vector.h"

// Return values of the various location functions
#define FULL_OUTSIDE 0
#define PARTIAL_INSIDE 1
#define FULL_INSIDE 2

typedef float vec3[3];		/* x, y, z */


typedef struct BBOX
{
	vec3 min;
	vec3 max;

	vec3 min_apex;
	vec3 min_left;
	vec3 min_center;
	vec3 min_right;

	vec3 max_apex;
	vec3 max_left;
	vec3 max_center;
	vec3 max_right;

} BBOX;



class CFrustum  
{
public:
	bool TriangleInFrustum(float A[3], float B[3], float C[3]);
	bool LineInFrustum(float A[3], float B[3]);
	bool CubeInFrustum(float fPoint[3], float fSize);
	bool SphereInFrustum(float fPoint[3], float fRadius);
	bool PointInFrustum( float x, float y, float z );
	bool PolygonInFrustum(BBOX *bbox);

	bool Polygon2(vec3 point1, vec3 point2, vec3 point3);

	void UpdateFrustum();
	int CubeLocation(float fPoint[], float fSize);
	int SphereLocation(float fPoint[3], float fRadius);
	bool RightParallelepipedInFrustum(float fMin[3], float fMax[3]);

	int cull_frustum(  BBOX *bbox ); 
	bool CubeFrustumD3D( float x, float y, float z, float size );
	void CalculateFrustum(vec3 CameraPos, vec3 Cdir, 
								float Aspect, float Fov, float zNear, float zFar);

	CFrustum();
	virtual ~CFrustum();

	// The six frustum planes
	float frustum[6][4];

};

#endif // !defined(AFX_FRUSTRUM_H__CA0D0C57_056C_44F8_8AFD_AFDE66FD2451__INCLUDED_)