opencv 绘图函数

// opencv 绘图函数
// CV_EXPORTS_W void line(CV_IN_OUT Mat& img, Point pt1, Point pt2, const Scalar& color,
//                     int thickness=1, int lineType=8, int shift=0);
//参数解释 
//.Mat& img: 输入输出图像 
//.Point pt1和pt2: 二维Point类的点坐标,由Point指定 
//.Scalar& color: 直线颜色 
//. int thickness = 1: 直线宽度，有默认值1 
//. int lineType = 8: 直线类型，默认值为8

//CV_EXPORTS_W void ellipse(CV_IN_OUT Mat& img, Point center, Size axes,
//	double angle, double startAngle, double endAngle,
//	const Scalar& color, int thickness = 1,
//	int lineType = 8, int shift = 0);
//参数解释
//.Mat& img: 输入输出图像
//.Point center : 由Point类指定的椭圆中心坐标
//.Size axes : 由Size类指定的椭圆所在区域矩形
//. double angle : 椭圆长轴偏离角度
//. double startAngle : 绘制椭圆起始角度
//. double endAngle : 绘制椭圆终点角度。如果设置startAngle为0，
//设置endAngle为360则表示整个椭圆
//. const Scalar& color : 椭圆颜色
//. int thickness = 1 : 椭圆边的线宽
//. int lineType = : 椭圆变线的类型
//
//CV_EXPORTS_W void rectangle(CV_IN_OUT Mat& img, Point pt1, Point pt2,
//	const Scalar& color, int thickness = 1,
//	int lineType = 8, int shift = 0);
//
! draws the rectangle outline or a solid rectangle covering rec in the image
//CV_EXPORTS void rectangle(CV_IN_OUT Mat& img, Rect rec,
//	const Scalar& color, int thickness = 1,
//	int lineType = 8, int shift = 0);
//可以看出其有两种参数传入方式。一类是用Point指定点，另一类是用Rect函数指定边长。
//.针对第一类指定方式，Point类指定的两个点分别为矩形的左上角点坐标和矩形左下角点坐标
//.Rect指定边长，查看其定义有如下语句
//说明Rect是int类型的数据结构，与Rect_等价。
//
//CV_EXPORTS_W void circle(CV_IN_OUT Mat& img, Point center, int radius,
//	const Scalar& color, int thickness = 1,
//	int lineType = 8, int shift = 0);
//参数解释
//.Mat& img: 输入输出图像
//.Point center : Point指定的一个二维点作为圆心
//. int radius : 圆的半径
//. const Scalar& color : Scalar指定的绘制圆的颜色
//. int thickness = 1 : 圆边的线宽
//. int lineType = 8 : 圆边线的类型
//
//填充多边形。其定义有两种形式
//
//CV_EXPORTS void fillPoly(Mat& img, const Point** pts,
//	const int* npts, int ncontours,
//	const Scalar& color, int lineType = 8, int shift = 0,
//	Point offset = Point());
//
//CV_EXPORTS_W void fillPoly(InputOutputArray img, InputArrayOfArrays pts,
//	const Scalar& color, int lineType = 8, int shift = 0,
//	Point offset = Point());

//.第一种形式定义，有Point** pts，是一个二阶指针，用来指定多边形顶点。
//多边形顶点不是某个特定点，而是多个点，所以用Point类定义的数组来表示顶点坐标，
//
//


#include 
#include 
#include 

using namespace std;
using namespace cv;

void M1(Mat img, double a1);
void M2(Mat img, Point c1);
void M3(Mat img, Point s1, Point s2);
void M4(Mat img);

const int w = 400;

int main()
{
	char awindow[] = "图 1";
	char rwindow[] = "图 2";

	// 创建空的图像
	//Mat aimage = Mat::zeros(w, w, CV_8UC3);
	Mat aimage = imread("F:/2.jpg");
	Mat rimage = Mat::zeros(w, w, CV_8UC3);

	M1(aimage, 90);
	M1(aimage, 0);
	M1(aimage, 45);
	M1(aimage, -45);

	M2(aimage, Point(w / 2.0, w / 2.0));

	namedWindow(awindow, WINDOW_AUTOSIZE);
	imshow(awindow, aimage);

	M4(rimage);
	// 创建一个矩形，
	rectangle(rimage, Point(0, 7 * w / 8.0), Point(w, w), Scalar(0, 255, 255), -1, 8);

	M3(rimage, Point(0, 15 * w / 16), Point(w, 15 * w / 16));
	M3(rimage, Point(w/4, 7 * w / 8), Point(w/4, w));
	M3(rimage, Point(w / 2, 7 * w / 8), Point(w / 2, w));
	M3(rimage, Point(3 * w / 4, 7 * w / 8), Point(3 * w / 4, w));

	namedWindow(rwindow, WINDOW_AUTOSIZE);
	imshow(rwindow, rimage);

	waitKey(0);
    return 0;
}

void M1(Mat img, double a1)
{
	int thickness = 2;
	int linetype = 8;

	ellipse(img, Point(w / 2.0, w / 2.0), Size(w / 4.0, w / 16.0), 
		a1, 0, 360, Scalar(0, 255, 255), thickness, linetype);
}

void M2(Mat img, Point c1)
{
	int thickness = -1;
	int linetype = 8;
	circle(img, c1, w / 32.0, Scalar(0, 0, 255), thickness, linetype);
}

void M3(Mat img, Point s1, Point s2)
{
	int thickness = 2;
	int linetype = 8;
	line(img, s1, s2, Scalar(0, 0, 0), thickness, linetype);
}

void M4(Mat img)
{
	int lineType = 8;
	Point rpoint[1][20];
	rpoint[0][0] = Point(w / 4.0, 7 * w / 8.0);
	rpoint[0][1] = Point(3 * w / 4.0, 7 * w / 8.0);
	rpoint[0][2] = Point(3 * w / 4.0, 13 * w / 16.0);
	rpoint[0][3] = Point(11 * w / 16.0, 13 * w / 16.0);
	rpoint[0][4] = Point(19 * w / 32.0, 3 * w / 8.0);
	rpoint[0][5] = Point(3 * w / 4.0, 3 * w / 8.0);
	rpoint[0][6] = Point(3 * w / 4.0, w / 8.0);
	rpoint[0][7] = Point(26 * w / 40.0, w / 8.0);
	rpoint[0][8] = Point(26 * w / 40.0, w / 4.0);
	rpoint[0][9] = Point(22 * w / 40.0, w / 4.0);
	rpoint[0][10] = Point(22 * w / 40.0, w / 8.0);
	rpoint[0][11] = Point(18 * w / 40.0, w / 8.0);
	rpoint[0][12] = Point(18 * w / 40.0, w / 4.0);
	rpoint[0][13] = Point(14 * w / 40.0, w / 4.0);
	rpoint[0][14] = Point(14 * w / 40.0, w / 8.0);
	rpoint[0][15] = Point(w / 4.0, w / 8.0);
	rpoint[0][16] = Point(w / 4.0, 3 * w / 8.0);
	rpoint[0][17] = Point(13 * w / 32.0, 3 * w / 8.0);
	rpoint[0][18] = Point(5 * w / 16.0, 13 * w / 16.0);
	rpoint[0][19] = Point(w / 4.0, 13 * w / 16.0);

	const Point* pp[1] = { rpoint[0] };
	int npt[] = { 20 };
	fillPoly(img, pp, npt, 1, Scalar(255, 255, 255), lineType);
}

参考大神网页：https://blog.csdn.net/keith_bb/article/details/53313202