C++使用opencv判断一个点是否在多边形之内

代码如下：

#include 

CvMat* g_pMatContour = NULL;

static void process(...)
{
    if (g_pMatContour == NULL)
    {
        float points[] ={470,240, 1670,168, 1846,688, 714,928};
        int nContourNum = 4;

        g_pMatContour = cvCreateMat(1, nContourNum, CV_32FC2);
        for (int i=0; ileft + pClip->width /2;
    ptTest.y = pClip->top  + pClip->height/2;

    double jl = cvPointPolygonTest(g_pMatContour, ptTest, 1);
    //jl > 0表示在内部。jl 0)
    {
        //WARNING MESSAGE
    }