www.pudn.com > roam.rar > Patch.h

// Patch.h: interface for the Patch class. 
// 
////////////////////////////////////////////////////////////////////// 
 
#if !defined(AFX_PATCH_H__557A5E51_212C_495E_9FBF_E72A4E41B0AD__INCLUDED_) 
#define AFX_PATCH_H__557A5E51_212C_495E_9FBF_E72A4E41B0AD__INCLUDED_ 
 
#if _MSC_VER > 1000 
#pragma once 
#endif // _MSC_VER > 1000 
#include "math.h" 
 
// Predefines... 
class Landscape; 
// Depth of variance tree: should be near SQRT(PATCH_SIZE) + 1 
#define VARIANCE_DEPTH (10) 
 
///////////////////////////////// 
////////    树结构    /////////// 
///////////////////////////////// 
struct TriTreeNode 
{ 
	TriTreeNode *LeftChild; 
	TriTreeNode *RightChild; 
	TriTreeNode *BaseNeighbor; 
	TriTreeNode *LeftNeighbor; 
	TriTreeNode *RightNeighbor; 
}; 
 
 
class Patch   
{ 
public: 
	virtual void Tessellate(); 
	virtual void Render(); 
	virtual void ComputeVariance(); 
	// Some encapsulation functions & extras 
	TriTreeNode *GetBaseLeft()  { return &m_BaseLeft; } 
	TriTreeNode *GetBaseRight() { return &m_BaseRight; } 
	char isDirty()     { return m_VarianceDirty; } 
	int  isVisibile( ) { return m_isVisible; } 
	virtual void SetVisibility( int eyeX, int eyeY, int leftX, int leftY, int rightX, int rightY ); 
	virtual void Reset(); 
	virtual void Init( int heightX, int heightY, int worldX, int worldY, double *hMap ); 
 
	 
	// The recursive half of the Patch Class 
	virtual void			Split( TriTreeNode *tri); 
	virtual void			RecursTessellate( TriTreeNode *tri, int leftX, int leftY, int rightX, int rightY, int apexX, int apexY, int node ); 
	virtual void			RecursRender( TriTreeNode *tri, int leftX, int leftY, int rightX, int rightY, int apexX, int apexY );	 
	virtual unsigned char	RecursComputeVariance(	int leftX,  int leftY,  double leftZ, 
													int rightX, int rightY, double rightZ, 
													int apexX,  int apexY,  double apexZ, 
													int node); 
 
	Patch(); 
	unsigned char m_isVisible;									// Is this patch visible in the current frame? 
	virtual ~Patch(); 
 
protected: 
	int eyeX; 
	int eyeY; 
	double *m_HeightMap;									    // 指向高程数据的指针 
	int m_WorldX,m_WorldY;										// 每一个字块偏移原始坐标的大小 
 
	unsigned char m_VarianceLeft[ 1<<(VARIANCE_DEPTH)];			// Left variance tree 
	unsigned char m_VarianceRight[1<<(VARIANCE_DEPTH)];			// Right variance tree 
 
	unsigned char *m_CurrentVariance;							// Which varience we are currently using. [Only valid during the Tessellate and ComputeVariance passes] 
	unsigned char m_VarianceDirty;								// Does the Varience Tree need to be recalculated for this Patch? 
 
	TriTreeNode m_BaseLeft;										// Left base triangle tree node 
	TriTreeNode m_BaseRight;									// Right base triangle tree node 
}; 
 
#endif // !defined(AFX_PATCH_H__557A5E51_212C_495E_9FBF_E72A4E41B0AD__INCLUDED_)