OpenCV 基本图形绘制函数

• 用于绘制直线的line函数；
• 用于绘制椭圆的ellipse函数；
• 用于绘制矩形的rectangle函数；
• 用于绘制圆的circle函数；
• 用于绘制填充的多边形的fillPoly函数。

#include <opencv2/core/core.hpp>
#include <opencv2/imgproc/imgproc.hpp>
#include <opencv2/highgui/highgui.hpp>

using namespace cv;
using namespace std;

#define WINDOW_WIDTH 600 // 定义窗口大小的宏
#define WINDOW_NAME1 "原子图"        //为窗口标题定义的宏 
#define WINDOW_NAME2 "多边形图以及画线"        //为窗口标题定义的宏 

/***绘制椭圆***/
void DrawEllipse(Mat img, double angle)
{
    int thickness = 2; //  线宽
    int lineType = 8; // 线性，8 代表联通线性

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

/*绘制实心圆*/
void DrawFilledCircle(Mat img, Point center)
{
    int thickness = -1; //  线粗-1，代表实心
    int lineType = 8; // 线性，8 代表联通线性

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

/*凹多边形绘制*/
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] }; // 多边形定点集
    int npt[] = { 20 }; // 多边形定点数目

    fillPoly(img, 
        ppt, 
        npt, 
        1, 
        Scalar(255, 255, 255),  // 多边形颜色：白色
        lineType);
}

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


int main(int argc, char ** argv)
{
    Mat atomImage = Mat::zeros(WINDOW_WIDTH, WINDOW_WIDTH, CV_8UC3);
    Mat rookImage = Mat::zeros(WINDOW_WIDTH, WINDOW_WIDTH, CV_8UC3);

    // 椭圆绘制
    DrawEllipse(atomImage, 0);
    DrawEllipse(atomImage, 90);
    DrawEllipse(atomImage, 45);
    DrawEllipse(atomImage, -45);
    // 绘制圆心
    DrawFilledCircle(atomImage, Point(WINDOW_WIDTH / 2, WINDOW_WIDTH / 2));


    // 绘制多边形
    DrawPolygon(rookImage);

    // 绘制矩形
    rectangle(rookImage,
        Point(0, 7 * WINDOW_WIDTH / 8),
        Point(WINDOW_WIDTH, WINDOW_WIDTH),
        Scalar(0, 255, 255),
        -1,
        8);

    // 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));

    // ---------------------------<3>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);
    return(0);
}

运行：

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参考：

《OpenCV3 编程入门》 毛星云 P104