一 Windows画图
1 图形绘制
1.1 图形绘制的方式
获取到画图的句柄,设备描写叙述符(DC)。使用对应的画图API。在设备上绘制图形
1.2 颜色
RGB,每种颜色8位,共24位颜色
32位颜色:颜色数量24为颜色,多出的8位表示灰度。
16位:颜色数量是2的16次方。
Win32下。颜色的定义使用 COLORREF。RGB的宏定义颜色
COLORREF nColor = RGB( 0, 0, 0 ); 黑色
COLORREF nColor = RGB( 255, 255, 255 ); 白色
COLORREF nColor = RGB( 255, 255, 255 ); 红色
从一个颜色值中获取RGB三色:
int nRed = GetRValue( DWord rgb )
int nGreen = GetGValue( DWord rgb )
int nBlue = GetBVakue( DWord rgb )
1.3 点的绘制和获取
绘制: SetPixel
COLORREF SetPixel( HDC hdc, // handle to DC int nXPos, // x-coordinate of pixel int nYPos, // y-coordinate of pixel
COLORREF crColor // 颜色值
);
获取: GetPixel
COLORREF GetPixel( HDC hdc, // handle to DC int nXPos, // x-coordinate of pixel int nYPos // y-coordinate of pixel );1.4 直线的绘制
MoveToEx移动当前点到指定位置
LineTo 从当前点绘制之前到指定位置
1.5 弧的绘制
Arc和AngleArc提供不同的绘制弧的方式
BOOL AngleArc( HDC hdc, // handle to device context int X, // x-coordinate of circle's center 圆心x坐标 int Y, // y-coordinate of circle's center 圆心y坐标 DWORD dwRadius, // circle's radius 园的半径 FLOAT eStartAngle, // arc's start angle 開始角度 FLOAT eSweepAngle // arc's sweep angle 夹角 );
圆弧的分割方式
int SetArcDirection(
HDC hdc, // handle to device context int ArcDirection // new arc direction );
BOOL Arc( HDC hdc, // handle to device context int nLeftRect, // x-coord of rectangle's upper-left corner int nTopRect, // y-coord of rectangle's upper-left corner int nRightRect, // x-coord of rectangle's lower-right corner int nBottomRect, // y-coord of rectangle's lower-right corner 外切矩形的坐标 int nXStartArc, // x-coord of first radial ending point int nYStartArc, // y-coord of first radial ending point int nXEndArc, // x-coord of second radial ending point int nYEndArc // y-coord of second radial ending point );
1.6 折线
BOOL Polyline( HDC hdc, // handle to device context CONST POINT *lppt, // array of endpoints int cPoints // number of points in array );
BOOL PolylineTo( HDC hdc, // handle to device context CONST POINT *lppt, // array of points DWORD cCount // number of points in array ); 与PolyLine类似, 在绘制PolyLine前。从当前点使用LineTo绘制直线到Polyline的第一个顶点
BOOL PolyPolyline( HDC hdc, // handle to device context CONST POINT *lppt, // array of points 全部点的数组 CONST DWORD *lpdwPolyPoints, // array of values 每组点的数量 DWORD cCount // number of entries in values array 分组的数量 );
1.7 Bizer曲线
BOOL PolyBezier( HDC hdc, // handle to device context CONST POINT* lppt, // endpoints and control points 点数组 DWORD cPoints // count of endpoints and control points 点的数量
);
1.8 圆角矩形
BOOL RoundRect( HDC hdc, // handle to DC int nLeftRect, // x-coord of upper-left corner of rectangle int nTopRect, // y-coord of upper-left corner of rectangle int nRightRect, // x-coord of lower-right corner of rectangle int nBottomRect, // y-coord of lower-right corner of rectangle int nWidth, // width of ellipse 生成圆角的椭圆的宽度 int nHeight // height of ellipse 生成圆角的椭圆的高度 );1.9 矩形
BOOL Rectangle( HDC hdc, // handle to DC int nLeftRect, // x-coord of upper-left corner of rectangle int nTopRect, // y-coord of upper-left corner of rectangle int nRightRect, // x-coord of lower-right corner of rectangle int nBottomRect // y-coord of lower-right corner of rectangle );1.10 椭圆
BOOL Ellipse( HDC hdc, // handle to DC int nLeftRect, // x-coord of upper-left corner of rectangle int nTopRect, // y-coord of upper-left corner of rectangle int nRightRect, // x-coord of lower-right corner of rectangle int nBottomRect // y-coord of lower-right corner of rectangle );1.11 pie饼
BOOL Pie( HDC hdc, // handle to DC int nLeftRect, // x-coord of upper-left corner of rectangle int nTopRect, // y-coord of upper-left corner of rectangle int nRightRect, // x-coord of lower-right corner of rectangle int nBottomRect, // y-coord of lower-right corner of rectangle int nXRadial1, // x-coord of first radial's endpoint int nYRadial1, // y-coord of first radial's endpoint int nXRadial2, // x-coord of second radial's endpoint int nYRadial2 // y-coord of second radial's endpoint );1.12 弦
BOOL Chord( HDC hdc, // handle to DC int nLeftRect, // x-coord of upper-left corner of rectangle int nTopRect, // y-coord of upper-left corner of rectangle int nRightRect, // x-coord of lower-right corner of rectangle int nBottomRect, // y-coord of lower-right corner of rectangle int nXRadial1, // x-coord of first radial's endpoint int nYRadial1, // y-coord of first radial's endpoint int nXRadial2, // x-coord of second radial's endpoint int nYRadial2 // y-coord of second radial's endpoint );1.13 多变形
BOOL Polygon( HDC hdc, // handle to DC CONST POINT *lpPoints, // polygon vertices int nCount // count of polygon vertices );
2 GDI画图对象 - 画笔
2.1 画笔的作用
能够控制线条的颜色、样式、宽度
2.2 画笔的使用
创建画笔
CreatePen
置成当前DC能够使用的画笔
SelectObject
绘制图形
从当前DC中取出画笔
SelectObject
销毁画笔
DeleteObject
3 GDI画图对象 - 画刷
3.1 画刷的作用
填充封闭图形,包含样式 颜色
3.2 画刷的使用
创建画刷
CreateSilidBrush
CreateHatchBrush
置成当前DC能够使用的画刷
SelectObject
绘制图形
取出画刷
SelectObject
销毁画刷
DeleteObject