www.pudn.com > 基本GIS系统开发.rar > Draw1.cpp, change:2005-05-24,size:3435b

// Draw1.cpp: implementation of the CDraw class. 
// 
////////////////////////////////////////////////////////////////////// 
 
#include "stdafx.h" 
#include "Draw.h" 
#include "Draw1.h" 
#include "math.h" 
#define pi 3.1415926 
#ifdef _DEBUG 
#undef THIS_FILE 
static char THIS_FILE[]=__FILE__; 
#define new DEBUG_NEW 
#endif 
 
////////////////////////////////////////////////////////////////////// 
// Construction/Destruction 
////////////////////////////////////////////////////////////////////// 
 
//CDraw::CDraw(); 
float GetAngle(float xx,float yy,float m_x,float m_y); 
float GetAngle(float xx,float yy,float m_x,float m_y) 
{ 
	float i; 
	i=(float)acos((m_x-xx)/sqrt((m_y-yy)*(m_y-yy)+(m_x-xx)*(m_x-xx))); 
    return i; 
} 
float CDraw::PointLine(float xx,float yy,float x1,float y1,float x2,float y2) 
{ 
	float a,b,c,ang1,ang2,ang; 
	a=CalDisp(x1,y1,xx,yy); 
	if(a==0.0) 
		return 0.0; 
	b=CalDisp(x2,y2,xx,yy); 
	if(b==0.0) 
		return 0.0; 
	c=CalDisp(x1,y1,x2,y2); 
	if(c==0.0) 
		return a; 
	if(a<b) 
	{ 
		if(fabs(y1-y2)=0.001) 
		{ 
			if(x1<x2) 
				ang1=0; 
			else 
				ang1=(float)pi; 
		} 
		else 
		{ 
			ang1=(float)acos((x2-x1)/c); 
			if(y1>y2) 
				ang1=(float)pi*2-ang1; 
		} 
		ang2=(float)acos((xx-x1)/a); 
		if(y1>yy) 
			ang2=(float)pi*2-ang2; 
		ang=ang2-ang1; 
		if(ang<0) 
			ang=-ang; 
		if(ang>pi) 
			ang=(float)pi*2-ang; 
		if(ang>pi/2) 
			return a; 
		else 
			return (a*(float)sin(ang)); 
	} 
	else 
	{ 
		if(fabs(y1-y2)=0.001) 
		{ 
			if(x1<x2) 
				ang1=(float)pi; 
			else 
				ang1=0; 
		} 
		else 
		{ 
			ang1=(float)acos((x1-x2)/c); 
			if(y2>y1) 
				ang1=(float)pi*2-ang1; 
		} 
		ang2=(float)acos((xx-x2)/b); 
		if(y2>yy) 
			ang2=(float)pi*2-ang2; 
		ang=ang2-ang1; 
		if(ang<0) 
			ang=-ang; 
		if(ang>pi) 
			ang=(float)pi*2-ang; 
		if(ang>pi/2) 
			return b; 
		else 
			return(b*(float)sin(ang)); 
	} 
} 
 
float CDraw::CalDisp(float x1,float y1,float x2,float y2) 
{ 
	return (float)sqrt((x1-x2)*(x1-x2)+(y1-y2)*(y1-y2)); 
} 
void CDraw::CalArea() 
{ 
} 
void CDraw::CalLong() 
{ 
} 
BOOL CDraw::PointRgn(float x,float y,int Numble,PointStruct* PointList,float blc) 
{ 
	CRgn rgn; 
	int x1,y1,i; 
	POINT* pPoint; 
	if(Numble<3) 
		return 0; 
	pPoint=new POINT[Numble]; 
	x1=(int)(x/blc); 
	y1=(int)(y/blc); 
	for(i=0;i<Numble;i++) 
	{ 
		pPoint[i].x=(int)((PointList[i].x)/blc); 
		pPoint[i].y=(int)((PointList[i].y)/blc); 
	} 
	rgn.CreatePolygonRgn(pPoint,Numble,0); 
	i=(rgn.PtInRegion(x1,y1)!=0); 
	rgn.DeleteObject(); 
	return i; 
} 
void CDraw::RotatePoint(float baseX,float baseY,float angle,float *xx,float *yy) 
{ 
	float xx1,yy1; 
	xx1=*xx; 
	yy1=*yy; 
	double angle1=GetAngle(baseX,baseY,xx1,yy1); 
	double j1=CalDisp(baseX,baseY,xx1,yy1); 
	xx1=baseX+j1*cos(angle+angle1); 
	yy1=baseY+j1*sin(angle+angle1); 
	*xx=xx1; 
	*yy=yy1; 
} 
float CDraw::GetAngle(float baseX,float baseY,float xx,float yy) 
{ 
	float r,ang; 
//	如果基点和计算点是同一个点 
	if(fabs(baseX-xx)=0.001&&fabs(baseY-yy)=0.001) 
		return 0; 
	if(fabs(baseX-xx)=0.001) 
	{ 
		if(yy>baseY) 
			ang=(float)(pi/2); 
		else 
			ang=(float)(pi*3/2); 
		return ang; 
	} 
	else 
	{ 
		r=(float)sqrt((xx-baseX)*(xx-baseX)+(yy-baseY)*(yy-baseY)); 
		double kk=(xx-baseX)/r; 
		ang=(float)acos(kk); 
		if(yy<baseY) 
			ang=(float)(pi*2)-ang; 
		return ang; 
	} 
 
 
} 
 
void CDraw::Delete(BOOL bDelete) 
{ 
	b_Delete=bDelete; 
} 
 
BOOL CDraw::IsFill() 
{ 
	return FALSE; 
} 
CDraw::~CDraw() 
{ 
 
}