opencvc函数（三）

自定义的绘制图形函数

1、【DrawEllipse( )函数】

  自定义的绘制函数，实现了绘制不同角度、相同尺寸的椭圆。

  声明：

void DrawEllipse( Mat img, double angle );//绘制椭圆

  定义：

void DrawEllipse( Mat img, double angle )
{
	int thickness = 2;
	int lineType = 8;

	ellipse( img,
		Point( WINDOW_WIDTH/2, WINDOW_WIDTH/2 ),
		Size( WINDOW_WIDTH/4, WINDOW_WIDTH/16 ),
		angle,
		0,
		360,
		Scalar( 255, 129, 0 ),
		thickness,
		lineType );
}

CV_EXPORTS void ellipse(InputOutputArray img, Point center, Size axes,
                        double angle, double startAngle, double endAngle,
                        const Scalar& color, int thickness = 1,
                        int lineType = LINE_8, int shift = 0);

2、【DrawFilledCircle( )函数】

  自定义的绘制函数，实现了实心圆的绘制。

  声明：
void DrawFilledCircle( Mat img, Point center );//绘制圆

  定义：

void DrawFilledCircle( Mat img, Point center )
{
	int thickness = -1;
	int lineType = 8;

	circle( img,
		center,
		WINDOW_WIDTH/32,
		Scalar( 0, 0, 255 ),
		thickness,
		lineType );
}

CV_EXPORTS void circle(InputOutputArray img, Point center, int radius,
                       const Scalar& color, int thickness = 1,
                       int lineType = LINE_8, int shift = 0);

3、【DrawPolygon( )函数】

  自定义的绘制函数，实现了凹多边形的绘制。

  声明：

void DrawPolygon( Mat img );//绘制多边形

  定义 ：

void DrawPolygon( Mat img )
{
	int lineType = 8;

	//创建一些点
	Point rookPoints[1][20];
	rookPoints[0][0]  = Point(    WINDOW_WIDTH/4,   7*WINDOW_WIDTH/8 );
	rookPoints[0][1]  = Point(  3*WINDOW_WIDTH/4,   7*WINDOW_WIDTH/8 );
	rookPoints[0][2]  = Point(  3*WINDOW_WIDTH/4,  13*WINDOW_WIDTH/16 );
	rookPoints[0][3]  = Point( 11*WINDOW_WIDTH/16, 13*WINDOW_WIDTH/16 );
	rookPoints[0][4]  = Point( 19*WINDOW_WIDTH/32,  3*WINDOW_WIDTH/8 );
	rookPoints[0][5]  = Point(  3*WINDOW_WIDTH/4,   3*WINDOW_WIDTH/8 );
	rookPoints[0][6]  = Point(  3*WINDOW_WIDTH/4,     WINDOW_WIDTH/8 );
	rookPoints[0][7]  = Point( 26*WINDOW_WIDTH/40,    WINDOW_WIDTH/8 );
	rookPoints[0][8]  = Point( 26*WINDOW_WIDTH/40,    WINDOW_WIDTH/4 );
	rookPoints[0][9]  = Point( 22*WINDOW_WIDTH/40,    WINDOW_WIDTH/4 );
	rookPoints[0][10] = Point( 22*WINDOW_WIDTH/40,    WINDOW_WIDTH/8 );
	rookPoints[0][11] = Point( 18*WINDOW_WIDTH/40,    WINDOW_WIDTH/8 );
	rookPoints[0][12] = Point( 18*WINDOW_WIDTH/40,    WINDOW_WIDTH/4 );
	rookPoints[0][13] = Point( 14*WINDOW_WIDTH/40,    WINDOW_WIDTH/4 );
	rookPoints[0][14] = Point( 14*WINDOW_WIDTH/40,    WINDOW_WIDTH/8 );
	rookPoints[0][15] = Point(    WINDOW_WIDTH/4,     WINDOW_WIDTH/8 );
	rookPoints[0][16] = Point(    WINDOW_WIDTH/4,   3*WINDOW_WIDTH/8 );
	rookPoints[0][17] = Point( 13*WINDOW_WIDTH/32,  3*WINDOW_WIDTH/8 );
	rookPoints[0][18] = Point(  5*WINDOW_WIDTH/16, 13*WINDOW_WIDTH/16 );
	rookPoints[0][19] = Point(    WINDOW_WIDTH/4,  13*WINDOW_WIDTH/16 );

	const Point* ppt[1] = { rookPoints[0] };
	int npt[] = { 20 };

	fillPoly( img,
		ppt,
		npt,
		1,
		Scalar( 255, 255, 255 ),
		lineType );
}

CV_EXPORTS void fillPoly(Mat& img, const Point** pts,
                         const int* npts, int ncontours,
                         const Scalar& color, int lineType = LINE_8, int shift = 0,
                         Point offset = Point() );

4、【DrawLine( )函数】

  自定义的绘制函数，实现了线的绘制。

  声明：

void DrawLine( Mat img, Point start, Point end );//绘制线段

  定义：

void DrawLine( Mat img, Point start, Point end )
{
	int thickness = 2;
	int lineType = 8;
	line( img,
		start,
		end,
		Scalar( 0, 0, 0 ),
		thickness,
		lineType );
}

void line(InputOutputArray img, Point pt1, Point pt2, const Scalar& color,
                     int thickness = 1, int lineType = LINE_8, int shift = 0);