OpenCV示例学习（二）：基本图形绘制算子：line(),circle(),fillPoly(), ellipse()

#include <opencv2/opencv.hpp>using namespace cv;#define WINDOW_NAME1 "【绘制图1】"        //为窗口标题定义的宏
#define WINDOW_NAME2 "【绘制图2】"        //为窗口标题定义的宏
#define WINDOW_WIDTH 600                 //定义窗口大小的宏void DrawEllipse(Mat img, double angle);//绘制椭圆
void DrawFilledCircle(Mat img, Point center);//绘制圆
void DrawPolygon(Mat img);//绘制多边形
void DrawLine(Mat img, Point start, Point end);//绘制线段int main(int argc, char *argv[])
{QCoreApplication a(argc, argv);// 创建空白的Mat图像Mat atomImage = Mat::zeros(WINDOW_WIDTH, WINDOW_WIDTH, CV_8UC3);Mat rookImage = Mat::zeros(WINDOW_WIDTH, WINDOW_WIDTH, CV_8UC3);//一、绘制化学中的原子示例图// 1、先绘制出椭圆DrawEllipse(atomImage, 90);DrawEllipse(atomImage, 0);DrawEllipse(atomImage, 45);DrawEllipse(atomImage, -45);// 2、再绘制圆心DrawFilledCircle(atomImage, Point(WINDOW_WIDTH / 2, WINDOW_WIDTH / 2));//二、绘制组合图//1、先绘制出椭圆DrawPolygon(rookImage);//2、绘制矩形rectangle(rookImage,Point(0, 7 * WINDOW_WIDTH / 8),Point(WINDOW_WIDTH, WINDOW_WIDTH),Scalar(0, 255, 255),-1,8);//3、绘制一些线段DrawLine(rookImage, Point(0, 15 * WINDOW_WIDTH / 16), Point(WINDOW_WIDTH, 15 * WINDOW_WIDTH / 16));DrawLine(rookImage, Point(WINDOW_WIDTH / 4, 7 * WINDOW_WIDTH / 8), Point(WINDOW_WIDTH / 4, WINDOW_WIDTH));DrawLine(rookImage, Point(WINDOW_WIDTH / 2, 7 * WINDOW_WIDTH / 8), Point(WINDOW_WIDTH / 2, WINDOW_WIDTH));DrawLine(rookImage, Point(3 * WINDOW_WIDTH / 4, 7 * WINDOW_WIDTH / 8), Point(3 * WINDOW_WIDTH / 4, WINDOW_WIDTH));//三、显示绘制出的图像imshow(WINDOW_NAME1, atomImage);moveWindow(WINDOW_NAME1, 0, 200);imshow(WINDOW_NAME2, rookImage);moveWindow(WINDOW_NAME2, WINDOW_WIDTH, 200);waitKey(0);
}

2）DrawEllipse()实现了绘制不同角度、相同尺寸的椭圆：

void DrawEllipse(Mat img, double angle)
{int thickness = 2;int lineType = 8;ellipse(img,Point(WINDOW_WIDTH / 2, WINDOW_WIDTH / 2),	// 椭圆中心Size(WINDOW_WIDTH / 4, WINDOW_WIDTH / 16),	// 外切矩形angle,										// 椭圆旋转角度0,360,Scalar(255, 129, 0),						// 蓝色thickness,									// 线宽lineType);									// 线性 （连通性）
}

3）DrawFilledCircle()实现了实心圆的绘制：

void DrawFilledCircle(Mat img, Point center)
{int thickness = -1;int lineType = 8;circle(img,center,WINDOW_WIDTH / 32,Scalar(0, 0, 255),thickness,lineType);
}

4）DrawPolygon()实现了凹多边形的绘制：

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] }; //	一个元素的 point 指针数组：每个元素表示指向一个point结构类型的存储地址//const Point** ppt = &(rookPoints[0]);//int npt[] = { 20 };int ival = 20;int *npt = &ival;fillPoly(img,&ppt[0],			// 多边形顶点集合npt,				// 多边形顶点数目1,Scalar(255, 255, 255),lineType);
}

5)DrawLine()实现了线的绘制

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