OpenCV 绘制正多边形

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 OpenCV 绘制正多边形

#include <iostream>    
#include <opencv2\core\core.hpp>
#include <opencv2\opencv.hpp>    
#include <opencv2\highgui\highgui.hpp>    
#include <opencv2\contrib\contrib.hpp>    

#include <fstream> 

using namespace cv;
using namespace std;

void DeleteRepetition(vector<Point> &Data)
{
	vector<Point>::iterator it, it1;
	for (it = ++Data.begin(); it != Data.end();) {
		it1 = find(Data.begin(), it, *it);
		if (it1 != it) it = Data.erase(it);
		else it++;
	}
}

void Patterns(Mat *src, vector<Point> Dots, int fill)
{
    DeleteRepetition(Dots);
	if (fill == -1)
	{
		Point *ImgDot = new Point(Dots.size());
		for (int i = 0; i < Dots.size(); i++) {
			ImgDot[i] = Dots[i];
		}
		const Point* ppt = ImgDot;
		int npt = Dots.size();
		RNG &rng = theRNG();
		Scalar color = Scalar(rng.uniform(100, 255), rng.uniform(100, 255), rng.uniform(100, 255));
		cv::fillPoly(*src, &ppt, &npt, 1, color);
	}
	else
	{
		Dots.push_back(Dots[0]);
		RNG &rng = theRNG();
		Scalar color = Scalar(rng.uniform(100, 255), rng.uniform(100, 255), rng.uniform(100, 255));
		for (int i = 0; i < Dots.size() - 1; i++)
		{
			line(*src, Dots[i], Dots[i + 1], color, fill);
		}
	}
}

// https://www.w3cplus.com/canvas/drawing-regular-polygons.html
// http://www.cnblogs.com/xcywt/p/9456526.html
// 图像、中心点、半径、边数、旋转角度、线宽
void EquilateralPolygon(Mat *src, Point origin, int radius, int brim, int rotate, int fill)
{
	if (brim < 3) return;
	if (rotate > 360) return;

#define PI 3.14159265
#define ROTATE_COUNT 180

	double nAgree = 360 / brim;  // 计算旋转角度
	double a = radius * cos(PI / brim);      // 计算垂直向下的长度
	double s = 2 * radius * sin(PI / brim);  // 计算边长

	vector<Point> Dots;
	Point D1, D2;
	D1.x = origin.x + radius*cos(-(((180 - nAgree) / 2) + rotate) * PI / 180);
	D1.y = origin.y - radius*sin(-(((180 - nAgree) / 2) + rotate) * PI / 180);
	D2.x = origin.x + radius*cos(-(((180 - nAgree) / 2) + nAgree + rotate) * PI / 180);
	D2.y = origin.y - radius*sin(-(((180 - nAgree) / 2) + nAgree + rotate) * PI / 180);

	// 第一条边的两个点
	Dots.push_back(D1);
	Dots.push_back(D2);

	for (int i = 0; i < brim - 2; i++)
	{
		double dSinRot = sin((nAgree * (i + 1)) * PI / 180);
		double dCosRot = cos((nAgree * (i + 1)) * PI / 180);
		int x = origin.x + dCosRot * (D2.x - origin.x) - dSinRot * (D2.y - origin.y);
		int y = origin.y + dSinRot * (D2.x - origin.x) + dCosRot * (D2.y - origin.y);
		Dots.push_back(Point(x, y));
	}
	Patterns(src, Dots, fill);
	Dots.clear();
}

int main()
{

	Mat	Img = Mat::zeros(800, 800, CV_8UC3);
	Point O = Point(400, 400);

	circle(Img, O, 2, Scalar(0, 0, 255), -1); //中心点

	EquilateralPolygon(&Img, O, 100, 3, 0, -1); // 填充的正三角形
	EquilateralPolygon(&Img, O, 200, 3, 0, 1);  // 不填充的正三角形
	EquilateralPolygon(&Img, O, 200, 3, 30, 1); // 不填充的正三角形，顺时针旋转30度
	EquilateralPolygon(&Img, O, 200, 3, 60, 1); // 不填充的正三角形，顺时针旋转60度
	EquilateralPolygon(&Img, O, 200, 3, 90, 1); // 不填充的正三角形，顺时针旋转90度
	EquilateralPolygon(&Img, O, 200, 3, 120, 1);// 不填充的正三角形，顺时针旋转120度
	EquilateralPolygon(&Img, O, 200, 3, 150, 1);// 不填充的正三角形，顺时针旋转150度
	EquilateralPolygon(&Img, O, 200, 3, 180, 1);// 不填充的正三角形，顺时针旋转180度

	EquilateralPolygon(&Img, O, 230, 4, 0, 2); // 不填充的正四边形
	EquilateralPolygon(&Img, O, 250, 5, 0, 3); // 不填充的正五边形
	EquilateralPolygon(&Img, O, 270, 6, 0, 4); // 不填充的正六边形
	EquilateralPolygon(&Img, O, 290, 7, 0, 5); // 不填充的正七边形
	EquilateralPolygon(&Img, O, 310, 8, 0, 6); // 不填充的正八边形
	EquilateralPolygon(&Img, O, 330, 9, 0, 7); // 不填充的正九边形
	EquilateralPolygon(&Img, O, 350, 10, 0, 8);// 不填充的正十边形

	imshow("正多边形", Img);
	waitKey(0);
	return 0;
}

效果如下：