OpenCV畫任意圓弧曲線

2020-01-26 13:34:44

字體：大中小

來源：轉載

供稿：網友

逆時針畫圓弧，原理：將360度分割成36份，分別標出每10度角度時的坐標點，然后將每個點連接起來。

#include <iostream> #include <opencv2/core/core.hpp>#include <opencv2/opencv.hpp> #include <opencv2/highgui/highgui.hpp> #include <opencv2/contrib/contrib.hpp>  #include <fstream> #include <windows.h> using namespace cv;using namespace std; // 圖像、圓心、開始點、結束點、線寬void DrawArc(Mat *src, Point ArcCenter, Point StartPoint, Point EndPoint, int Fill){ if (Fill <= 0) return;  vector<Point> Dots; double Angle1 = atan2((StartPoint.y - ArcCenter.y), (StartPoint.x - ArcCenter.x)); double Angle2 = atan2((EndPoint.y - ArcCenter.y), (EndPoint.x - ArcCenter.x)); double Angle = Angle1 - Angle2; Angle = Angle * 180.0 / CV_PI;  if (Angle < 0) Angle = 360 + Angle; if (Angle == 0) Angle = 360; int brim = floor(Angle / 10); // 向下取整  Dots.push_back(StartPoint); for (int i = 0; i < brim; i++) { double dSinRot = sin(-(10 * (i + 1)) * CV_PI / 180); double dCosRot = cos(-(10 * (i + 1)) * CV_PI / 180); int x = ArcCenter.x + dCosRot * (StartPoint.x - ArcCenter.x) - dSinRot * (StartPoint.y - ArcCenter.y); int y = ArcCenter.y + dSinRot * (StartPoint.x - ArcCenter.x) + dCosRot * (StartPoint.y - ArcCenter.y); Dots.push_back(Point(x, y)); } Dots.push_back(EndPoint); 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); } Dots.clear();} int main(){ Mat Img = Mat::zeros(800, 800, CV_8UC3); int64 tim = getTickCount();  // 坐標零點 400,400 Point ZeroPoint = Point(400, 400); // 起始坐標 150，-100 Point StartPoint = Point(ZeroPoint.x +150, ZeroPoint.y - (-100)); // 結束坐標 -150，-100 Point EndPoint = Point(ZeroPoint.x - 150, ZeroPoint.y - (-100));  // 圓心相對起始點的坐標 -150,200 int I = StartPoint.x - 150; int J = StartPoint.y - (+200);  Point Arc = Point(I, J);  // 顯示圓心坐標 circle(Img, Arc, 5, Scalar(0, 0, 255), -1); // 顯示起始點坐標 circle(Img, StartPoint, 5, Scalar(255, 0, 0), -1); // 顯示結束點坐標 circle(Img, EndPoint, 5, Scalar(0, 255, 0), -1);  // 圖像、圓心、開始點、結束點、線寬 DrawArc(&Img, Arc, StartPoint, EndPoint, 2); imshow("正多邊形", Img);  tim = getTickCount() - tim; printf("處理耗時: %fms/n/n", tim * 1000 / getTickFrequency()); waitKey(0); return 0;}

效果如下：