cgdraw2.cpp

本上机平台专门为《计算机辅助设计技术基础》课程中的vC语言编程和交互技术与用户接口实验部分设计。

#include "stdafx.h"
#include "math.h"
#include "cgdraw.h"
#include "Dib.h"
extern HPEN pen;
void CCgDraw::load(CDC *pDC)
{
    extern CString name;
	IPicture *pPic;
    IStream *pStm;
    CFileStatus fstatus;
    CFile file;
    LONG cb;
	extern BOOL bLoad;
	bLoad=false;
    if (file.Open((LPCSTR)name,CFile::modeRead)&&file.GetStatus((LPCSTR)name,fstatus)&&((cb =fstatus.m_size) != -1))
   {
   HGLOBAL hGlobal = GlobalAlloc(GMEM_MOVEABLE, cb);
   LPVOID pvData = NULL;
   if (hGlobal != NULL)
   {
   if ((pvData = GlobalLock(hGlobal)) != NULL)
   {
    file.ReadHuge(pvData, cb);
    GlobalUnlock(hGlobal);
    CreateStreamOnHGlobal(hGlobal, TRUE, &pStm);
    if(SUCCEEDED(OleLoadPicture(pStm,fstatus.m_size,TRUE,IID_IPicture,(LPVOID*)&pPic)))
    {
     OLE_XSIZE_HIMETRIC hmWidth;
     OLE_YSIZE_HIMETRIC hmHeight;
     pPic->get_Width(&hmWidth);
     pPic->get_Height(&hmHeight);
     double fX,fY;
    fX=(double)pDC->GetDeviceCaps(HORZRES)*(double)hmWidth/((double)pDC->GetDeviceCaps(HORZSIZE)*100.0);
    fY=(double)pDC->GetDeviceCaps(VERTRES)*(double)hmHeight/((double)pDC->GetDeviceCaps(VERTSIZE)*100.0);
    if(FAILED(pPic->Render(*pDC,0,0,(DWORD)fX,(DWORD)fY,0,hmHeight,hmWidth,-hmHeight,NULL)))
     AfxMessageBox("Failed To Render The picture!");
     pPic->Release();
    }
    else
    AfxMessageBox("Error Loading Picture From Stream!");
    }
    }
    }
    else
    AfxMessageBox("Can't Open Image File!");
}
void CCgDraw::init(CDC *pDC)
{
	pDC->SelectObject(pen);
}
void CCgDraw::deletepen()
{
	DeleteObject(pen);
}
void CCgDraw::free(CDC *pDC,CPoint oldMousePoint,CPoint newMousePoint)
{   if ((newMousePoint.x!=-1)||(newMousePoint.y!=-1))
{pDC->MoveTo(oldMousePoint.x,oldMousePoint.y);
pDC->LineTo(newMousePoint.x,newMousePoint.y);
}
}
void CCgDraw::line(CDC *pDC, CPoint *point)
{	
	pDC->MoveTo(point[0]);
	pDC->LineTo(point[1]);
}

// 作业1:用几何变换原理,画矩形绕其左下角旋转图,
//       间隔36度,共画10个.
void CCgDraw::rotate(CDC *pDC)
{
	int i;
	double x1=0,x2=0,x3=0,y1=0,y2=0,y3=0,g,a=90,b=60,c=300,d=200,q,m;
        q=sqrt(a*a+b*b);
	g=atan2(b,a);
       m=3.14159265453;     
	for(i=1;i<=10;i++)
	{
	 x1=a*cos(i*m/5-m/5)+c;
	 y1=a*sin(i*m/5-m/5)+d;
	 pDC->MoveTo((int)c,(int)d);
	 pDC->LineTo((int)x1,(int)y1);

	 x2=q*cos(i*m/5+g-m/5)+c;
	 y2=q*sin(i*m/5+g-m/5)+d;
	 pDC->MoveTo((int)x1,(int)y1);
	 pDC->LineTo((int)x2,(int)y2);

	 x3=b*cos(m/2+i*m/5-m/5)+c;
	 y3=b*sin(m/2+i*m/5-m/5)+d;
	 pDC->MoveTo((int)x2,(int)y2);
	 pDC->LineTo((int)x3,(int)y3);

	 pDC->MoveTo((int)x3,(int)y3);
	 pDC->LineTo((int)c,(int)d);
	}

}

// 作业2:编写用几何变换的方法生成直线箭头.
//       point[0],point[1]:箭头的两个顶点;
//       point[2].x:箭头长;
//       point[2].y:箭头宽;
//       point[3].x:箭头类型(=1 单向;=2 双向).
/*基本算法如下：
  以该直线为X轴，直线的一个端点为原点建立坐标系，然后求出新的坐标系下的箭头顶点的坐标，
  再将新坐标系下的坐标通过旋转及平移变换到原坐标系下即可。*/
 
void CCgDraw::arrow(CDC *pDC, CPoint *point)
{
	//计算直线两端点之间距离d
	double d=sqrt((double)(point[1].x-point[0].x)*(point[1].x-point[0].x)+(double)(point[1].y-point[0].y)*(point[1].y-point[0].y));
	
	int L=point[2].x;
	int W=point[2].y;
	int M=point[3].x;
 
	POINT poi[4];

	//计算直线倾角的cos,sin值cs,sn
	double cs=(point[1].x-point[0].x)/d;
	double sn=(point[1].y-point[0].y)/d;
 
	//如果M=1，则绘制单向箭头
	if(M==1)
	{
		if(d<L) return;
		pDC->MoveTo(point[0]);
		pDC->LineTo(point[1]);

		////////////////////////////////////////////////////////////////////////////////
		//利用cos及sin进行几何变换，分别求得箭头的除去在直线上的顶点外的其它两个顶点的坐标，
		//然后将这三个点用直线一一连接起来
		poi[0].x=(long)((d-L)*cs-W*sn+point[0].x);
		poi[0].y=(long)((d-L)*sn+W*cs+point[0].y);
		pDC->MoveTo(point[1]);
		pDC->LineTo(poi[0]);
		poi[1].x=(long)((d-L)*cs+W*sn+point[0].x);
		poi[1].y=(long)((d-L)*sn-W*cs+point[0].y);
		pDC->MoveTo(poi[0]);
		pDC->LineTo(poi[1]);
		pDC->LineTo(point[1]);
	}

	//如果M=1，则绘制双向箭头，方法与绘制单向箭头类似
	if(M==2)
	{
		if(d<2*L) return;
		pDC->MoveTo(point[0]);
		pDC->LineTo(point[1]);
		
		poi[0].x=(long)((d-L)*cs-W*sn+point[0].x);
		poi[0].y=(long)((d-L)*sn+W*cs+point[0].y);
		pDC->LineTo(poi[0]);
		poi[1].x=(long)((d-L)*cs+W*sn+point[0].x);
		poi[1].y=(long)((d-L)*sn-W*cs+point[0].y);
		pDC->LineTo(poi[1]);
		pDC->LineTo(point[1]);
		pDC->MoveTo(point[0]);
		
		poi[2].x=(long)(L*cs-W*sn+point[0].x);
		poi[2].y=(long)(L*sn+W*cs+point[0].y);
		pDC->LineTo(poi[2]);
		poi[3].x=(long)(L*cs+W*sn+point[0].x);
		poi[3].y=(long)(L*sn-W*cs+point[0].y);
		pDC->LineTo(poi[3]);
		pDC->LineTo(point[0]);
	}
}

// 作业3:画两个已知圆的公切线.
//       point[0],point[1]:第一,二个圆的圆心;
//       point[2].x:第一个圆的半径;
//       point[2].y:第二个圆的半径.
void CCgDraw::publine(CDC *pDC, CPoint *point)
{
	//绘制两个圆
	pDC->Ellipse(point[0].x-point[2].x,point[0].y-point[2].x,point[0].x+point[2].x,point[0].y+point[2].x);
	pDC->Ellipse(point[1].x-point[2].y,point[1].y-point[2].y,point[1].x+point[2].y,point[1].y+point[2].y);

	//求圆心间距d
	double d=sqrt((double)(point[1].x-point[0].x)*(point[1].x-point[0].x)+(double)(point[1].y-point[0].y)*(point[1].y-point[0].y));
	//求两圆半径差dr
	double dr;
	dr=point[2].x-point[2].y;
	if((int)d<abs((int)dr)) return;
	

	//如果两圆不相交，则求内外公切线
	if(d>=(point[2].x+point[2].y))
	{
		//求出圆心连线在原坐标系的倾角的cos,sin值cs,sn
		double cs=(point[1].x-point[0].x)/d;
		double sn=(point[1].y-point[0].y)/d;
		
		POINT poi[8];
		POINT p[8];
		
		/*以圆心连线为x轴，point1为原点建立坐标系，x轴的方向为由point1到point2的方向，
		然后进行下面的操作：*/
		
		//求出通过外公切线切点的半径与圆心连线的夹角的cos,sin值cst,snt
		double snt=sqrt(d*d-dr*dr)/d;
		double cst=dr/d;

		///////////////////////////////////////////
		//求出在新的坐标系下外公切线与圆的切点的坐标
		poi[0].x=(long)(point[2].x*cst);
		poi[0].y=(long)(point[2].x*snt);
		poi[1].x=(long)(point[2].y*cst+d);
		poi[1].y=(long)(point[2].y*snt);
		poi[2].x=poi[0].x;
		poi[2].y=0-poi[0].y;
		poi[3].x=poi[1].x;
		poi[3].y=0-poi[1].y;

		//求出通过内公切线切点的半径与圆心连线的夹角的cos,sin值cst1,snt1
		double snt1=sqrt(d*d-(point[2].x+point[2].y)*(point[2].x+point[2].y))/d;
		double cst1=(point[2].x+point[2].y)/d;

		///////////////////////////////////////////
		//求出在新的坐标系下内公切线与圆的切点的坐标
		poi[4].x=(long)(point[2].x*cst1);
		poi[4].y=(long)(point[2].x*snt1);
		poi[5].x=(long)(d-point[2].y*cst1);
		poi[5].y=(long)(0-point[2].y*snt1);
		poi[6].x=poi[4].x;
		poi[6].y=0-poi[4].y;
		poi[7].x=poi[5].x;
		poi[7].y=0-poi[5].y;
		int i;

		//通过几何变换将切点在新的坐标系下的坐标变换到原坐标系
		for(i=0;i<8;i++)
		{
			p[i].x=(long)(poi[i].x*cs-poi[i].y*sn+point[0].x);
			p[i].y=(long)(poi[i].x*sn+poi[i].y*cs+point[0].y);
		}

		//绘制切线
		pDC->MoveTo(p[0]);
		pDC->LineTo(p[1]);
		pDC->MoveTo(p[2]);
		pDC->LineTo(p[3]);
		pDC->MoveTo(p[4]);
		pDC->LineTo(p[5]);
		pDC->MoveTo(p[6]);
		pDC->LineTo(p[7]);
	}

	//如果两圆相交，则只求外公切线，方法与前面类似
	if(dr<(point[2].x+point[2].y))
	{
		double cs=(point[1].x-point[0].x)/d;
		double sn=(point[1].y-point[0].y)/d;
		
		POINT poi[4];
		POINT p[4];
		
		double snt=sqrt(d*d-dr*dr)/d;
		double cst=dr/d;
		poi[0].x=(long)(point[2].x*cst);
		poi[0].y=(long)(point[2].x*snt);
		poi[1].x=(long)(point[2].y*cst+d);
		poi[1].y=(long)(point[2].y*snt);
		poi[2].x=poi[0].x;
		poi[2].y=0-poi[0].y;
		poi[3].x=poi[1].x;
		poi[3].y=0-poi[1].y;
		
		int i;
		for(i=0;i<4;i++)
		{
			p[i].x=(long)(poi[i].x*cs-poi[i].y*sn+point[0].x);
			p[i].y=(long)(poi[i].x*sn+poi[i].y*cs+point[0].y);
		}
		
		pDC->MoveTo(p[0]);
		pDC->LineTo(p[1]);
		pDC->MoveTo(p[2]);
		pDC->LineTo(p[3]);
	}
}

// 作业4:画三次Bezier曲线.
//       num:型值点数
//       point[0] ~ point[num-1]:型值点坐标.
void CCgDraw::bezier(CDC *pDC, int num, CPoint *point)
{