矩形和区域

下面有三个绘图函数需要一个指向矩形结构的指针：

FillRect(hdc,&rect,hbursh);//填充

FrameRect(hdc,&rect,hbrush);//掏空

InvertRect(hdc,&rect);//内部取反

[cpp]
case WM_PAINT: 
            hdc=BeginPaint(hwnd,&ps); 
            //GetClientRect(hwnd,&rect);  
             
            //hrgn=CreateRectRgn(100,100,300,300);  
            //hbrush=CreateSolidBrush(RGB(255,0,0));  
            //FillRgn(hdc,hrgn,hbrush);  
            //InvertRgn(hdc,hrgn);//取反  
            //FrameRgn(hdc,hrgn,hbrush,0,0);  
 
             
            r1.left=100; 
            r1.top=100; 
            r1.right=200; 
            r1.bottom=200; 
            hbrush=CreateSolidBrush(RGB(255,0,0));//创建画刷  
            FillRect(hdc,&r1,hbrush); 
 
            r2.left=200; 
            r2.top=100; 
            r2.right=300; 
            r2.bottom=200; 
            FrameRect(hdc,&r2,hbrush); 
 
            r3.left=300; 
            r3.top=100; 
            r3.right=400; 
            r3.bottom=200; 
            InvertRect(hdc,&r3); 
 
            EndPaint(hwnd,&ps); 
            return 0; 

case WM_PAINT:
   hdc=BeginPaint(hwnd,&ps);
   //GetClientRect(hwnd,&rect);
   
   //hrgn=CreateRectRgn(100,100,300,300);
   //hbrush=CreateSolidBrush(RGB(255,0,0));
   //FillRgn(hdc,hrgn,hbrush);
   //InvertRgn(hdc,hrgn);//取反
   //FrameRgn(hdc,hrgn,hbrush,0,0);

   
   r1.left=100;
   r1.top=100;
   r1.right=200;
   r1.bottom=200;
   hbrush=CreateSolidBrush(RGB(255,0,0));//创建画刷
   FillRect(hdc,&r1,hbrush);

   r2.left=200;
   r2.top=100;
   r2.right=300;
   r2.bottom=200;
   FrameRect(hdc,&r2,hbrush);

   r3.left=300;
   r3.top=100;
   r3.right=400;
   r3.bottom=200;
   InvertRect(hdc,&r3);

   EndPaint(hwnd,&ps);
   return 0;

下面还有八个关于矩形的操作：

OffsetRect(&rect,x,y) 将矩形移动
InflateRect(&rect,x,y) 增大缩小矩形的尺寸
SetRectEmpty(&rect) 把矩形结构各字段设置为0
CopyRect(&DestRect,&ScrRect) 将一个矩形结构复制到另一个矩形结构
IntersectRect(&destRect,&SrcRect1,&SrcRect2) 获取两个矩形的交集
UnionRect(&DestRect,&SrcRect1,&SrcRect2) 获取两个矩形的并集
bEmpty=IsRectEmpty(&Rect) 判断矩形是否为空
bInRect=PtInRect(&rect,point) 判断点是否在矩形内部

 

区域跟矩形一样，有以下四个绘图函数

[cpp]
FillRgn(hdc,hrgn,hbrush); 
FrameRgn(hdc,hbrush,xFrame,yFrame); 
InvertRgn(hdc,hrgn); 
PaintRgn(hdc,hrgn); 

FillRgn(hdc,hrgn,hbrush);
FrameRgn(hdc,hbrush,xFrame,yFrame);
InvertRgn(hdc,hrgn);
PaintRgn(hdc,hrgn);[cpp] view plaincopyprint?DeleteObject(hrgn); 

DeleteObject(hrgn);[cpp] view plaincopyprint?SelectObject(hdc,hrgn)=SelectClipRgn(hdc,hrgn); 

SelectObject(hdc,hrgn)=SelectClipRgn(hdc,hrgn);使得矩形，区域有效和无效的函数

[cpp]
InvalidateRect       ValidateRect 
InvalidateRgn        ValidateRgn 

InvalidateRect       ValidateRect
InvalidateRgn        ValidateRgn下面是简单的例子：

[cpp]
case WM_PAINT: 
            hdc=BeginPaint(hwnd,&ps); 
            //GetClientRect(hwnd,&rect);  
             
            //hrgn=CreateRectRgn(100,100,300,300);  
            //hbrush=CreateSolidBrush(RGB(255,0,0));  
            //FillRgn(hdc,hrgn,hbrush);  
            //InvertRgn(hdc,hrgn);//取反  
            //FrameRgn(hdc,hrgn,hbrush,0,0);  
 
             
            r1.left=100; 
            r1.top=100; 
            r1.right=200; 
            r1.bottom=200; 
            hbrush=CreateSolidBrush(RGB(255,0,0));//创建画刷  
            //FillRect(hdc,&r1,hbrush);  
 
            r2.left=150; 
            r2.top=100; 
            r2.right=250; 
            r2.bottom=200; 
            //FrameRect(hdc,&r2,hbrush);  
 
            IntersectRect(&r3,&r1,&r2);//r1,r2矩形取交集，存放在r3  
            FillRect(hdc,&r3,hbrush); 
            flag=(int)IsRectEmpty(&r3);//判断矩形是否为空  
            TextOut(hdc,300,300,szBuffer,wsprintf(szBuffer,TEXT("%d"),flag)); 
 
            EndPaint(hwnd,&ps); 
            return 0; 

case WM_PAINT:
   hdc=BeginPaint(hwnd,&ps);
   //GetClientRect(hwnd,&rect);
   
   //hrgn=CreateRectRgn(100,100,300,300);
   //hbrush=CreateSolidBrush(RGB(255,0,0));
   //FillRgn(hdc,hrgn,hbrush);
   //InvertRgn(hdc,hrgn);//取反
   //FrameRgn(hdc,hrgn,hbrush,0,0);

   
   r1.left=100;
   r1.top=100;
   r1.right=200;
   r1.bottom=200;
   hbrush=CreateSolidBrush(RGB(255,0,0));//创建画刷
   //FillRect(hdc,&r1,hbrush);

   r2.left=150;
   r2.top=100;
   r2.right=250;
   r2.bottom=200;
   //FrameRect(hdc,&r2,hbrush);

   IntersectRect(&r3,&r1,&r2);//r1,r2矩形取交集，存放在r3
   FillRect(hdc,&r3,hbrush);
   flag=(int)IsRectEmpty(&r3);//判断矩形是否为空
   TextOut(hdc,300,300,szBuffer,wsprintf(szBuffer,TEXT("%d"),flag));

   EndPaint(hwnd,&ps);
   return 0;

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[cpp]
hrgn=CreateRectRgn(xleft,ytop,xright,ybottom); 
hrgn=CreateRectRgnIndirect(&rect); 
hrgn=CreateEllipticRgn(xleft,ytop,xright,ybottom); 
hrgn=CreatePolygonRgn(&point,icount,ipolyFillMode); 

hrgn=CreateRectRgn(xleft,ytop,xright,ybottom);
hrgn=CreateRectRgnIndirect(&rect);
hrgn=CreateEllipticRgn(xleft,ytop,xright,ybottom);
hrgn=CreatePolygonRgn(&point,icount,ipolyFillMode);

 

作者：zh634455283