cv::Point2f recursive_bezier(const std::vector<cv::Point2f> &control_points, float t)
{
// TODO: Implement de Casteljau's algorithm
//return cv::Point2f();
if (control_points.size() < 2)
{
return control_points[0];
}
std::vector<cv::Point2f> temp_control_points = {};
for (int i = 0; i < control_points.size() - 1; i++)
{
cv::Point2f temp_point = (1 - t) * control_points[i] + t * control_points[i + 1];
temp_control_points.push_back(temp_point);
}
return recursive_bezier(temp_control_points, t);
}
bezier每次传入的t都会返回一个在对应t下贝塞尔曲线上的点。
void bezier(const std::vector<cv::Point2f> &control_points, cv::Mat &window)
{
// TODO: Iterate through all t = 0 to t = 1 with small steps, and call de Casteljau's
// recursive Bezier algorithm.
for (double t = 0.0; t <= 1.0; t += 0.001)
{
cv::Point2f point = recursive_bezier(control_points, t);
window.at<cv::Vec3b>(point.y, point.x)[1] = 255;
}
修改点的数量只需要修改mouse_handler里的点的数量的限制和main函数点的数量
void mouse_handler(int event, int x, int y, int flags, void *userdata)
{
if (event == cv::EVENT_LBUTTONDOWN && control_points.size() < 5)
{
std::cout << "Left button of the mouse is clicked - position (" << x << ", "
<< y << ")" << '\n';
control_points.emplace_back(x, y);
}
}
if (control_points.size() == 5)
{
naive_bezier(control_points, window);
bezier(control_points, window);
cv::imshow("Bezier Curve", window);
cv::imwrite("my_bezier_curve.png", window);
key = cv::waitKey(0);
return 0;
}
结果