c++求两条直线的交点

交点"/>

c++求两条直线的交点

一、已知每条直线的两个点：

cv::Point2d get2lineIPoint(cv::Point2d lineOnePt1, cv::Point2d lineOnePt2, cv::Point2d lineTwoPt1, cv::Point2d lineTwoPt2)
{double x;double y;cv::Point2d result(-1,-1);double k = (lineOnePt1.y - lineOnePt2.y) / (lineOnePt1.x- lineOnePt2.x);double b = lineOnePt1.y - k * lineOnePt1.x;double k1 = (lineTwoPt1.y - lineTwoPt2.y) / (lineTwoPt1.x - lineTwoPt2.x);double b1 = lineTwoPt1.y - k1 * lineTwoPt1.x;x = (b1 - b) / (k - k1);y = k * x + b;result.x = x;result.y = y;return result;
}

测试如下：

二、已知每条直线的一个点和方向(点斜式直线)

cv::Point2d get2lineIPoint(cv::Vec4f lineParam1, cv::Vec4f lineParam2)
{//Vec4f :参数的前半部分给出的是直线的方向，而后半部分给出的是直线上的一点cv::Point2d result(-1, -1);double cos_theta = lineParam1[0];double sin_theta = lineParam1[1];double x = lineParam1[2];double y = lineParam1[3];double k = sin_theta / cos_theta;double b = y - k * x;cos_theta = lineParam2[0];sin_theta = lineParam2[1];x = lineParam2[2];y = lineParam2[3];double k1 = sin_theta / cos_theta;double b1 = y - k1 * x;result.x = (b1 - b) / (k - k1);result.y = k * result.x + b;return result;
}