c++转换为js

Question

这段代码转换为js，求帮忙
void createCurve(CvPoint *originPoint,int originCount,vector<CvPoint> &curvePoint){

//控制点收缩系数 ，经调试0.6较好，CvPoint是OpenCV的，可自行定义结构体(x,y)  
float scale = 0.6;  
CvPoint midpoints[originCount];  
//生成中点       
for(int i = 0 ;i < originCount ; i++){      
    int nexti = (i + 1) % originCount;  
    midpoints[i].x = (originPoint[i].x + originPoint[nexti].x)/2.0;  
    midpoints[i].y = (originPoint[i].y + originPoint[nexti].y)/2.0;  
}      
  
//平移中点  
CvPoint extrapoints[2 * originCount];   
for(int i = 0 ;i < originCount ; i++){  
     int nexti = (i + 1) % originCount;  
     int backi = (i + originCount - 1) % originCount;  
     CvPoint midinmid;  
     midinmid.x = (midpoints[i].x + midpoints[backi].x)/2.0;  
     midinmid.y = (midpoints[i].y + midpoints[backi].y)/2.0;  
     int offsetx = originPoint[i].x - midinmid.x;  
     int offsety = originPoint[i].y - midinmid.y;  
     int extraindex = 2 * i;  
     extrapoints[extraindex].x = midpoints[backi].x + offsetx;  
     extrapoints[extraindex].y = midpoints[backi].y + offsety;  
     //朝 originPoint[i]方向收缩   
     int addx = (extrapoints[extraindex].x - originPoint[i].x) * scale;  
     int addy = (extrapoints[extraindex].y - originPoint[i].y) * scale;  
     extrapoints[extraindex].x = originPoint[i].x + addx;  
     extrapoints[extraindex].y = originPoint[i].y + addy;  
       
     int extranexti = (extraindex + 1)%(2 * originCount);  
     extrapoints[extranexti].x = midpoints[i].x + offsetx;  
     extrapoints[extranexti].y = midpoints[i].y + offsety;  
     //朝 originPoint[i]方向收缩   
     addx = (extrapoints[extranexti].x - originPoint[i].x) * scale;  
     addy = (extrapoints[extranexti].y - originPoint[i].y) * scale;  
     extrapoints[extranexti].x = originPoint[i].x + addx;  
     extrapoints[extranexti].y = originPoint[i].y + addy;  
       
}      
  
CvPoint controlPoint[4];  
//生成4控制点，产生贝塞尔曲线  
for(int i = 0 ;i < originCount ; i++){  
       controlPoint[0] = originPoint[i];  
       int extraindex = 2 * i;  
       controlPoint[1] = extrapoints[extraindex + 1];  
       int extranexti = (extraindex + 2) % (2 * originCount);  
       controlPoint[2] = extrapoints[extranexti];  
       int nexti = (i + 1) % originCount;  
       controlPoint[3] = originPoint[nexti];      
       float u = 1;  
       while(u >= 0){  
           int px = bezier3funcX(u,controlPoint);  
           int py = bezier3funcY(u,controlPoint);  
           //u的步长决定曲线的疏密  
           u -= 0.005;  
           CvPoint tempP = cvPoint(px,py);  
           //存入曲线点   
           curvePoint.push_back(tempP);  
       }      
}  

}
//三次贝塞尔曲线
float bezier3funcX(float uu,CvPoint *controlP){
float part0 = controlP[0].x uu uu * uu;
float part1 = 3 controlP[1].x uu uu (1 - uu);
float part2 = 3 controlP[2].x uu (1 - uu) (1 - uu);
float part3 = controlP[3].x (1 - uu) (1 - uu) * (1 - uu);
return part0 + part1 + part2 + part3;
}
float bezier3funcY(float uu,CvPoint *controlP){
float part0 = controlP[0].y uu uu * uu;
float part1 = 3 controlP[1].y uu uu (1 - uu);
float part2 = 3 controlP[2].y uu (1 - uu) (1 - uu);
float part3 = controlP[3].y (1 - uu) (1 - uu) * (1 - uu);
return part0 + part1 + part2 + part3;
}

Answer 1

把类型去掉，修改一下声明方式就行了，大概其是（没测试）：

function createCurve(originPoint, originCount, curvePoint){
//控制点收缩系数 ，经调试0.6较好，CvPoint是OpenCV的，可自行定义结构体(x,y)  
let scale = 0.6;  
let midpoints = [];  
//生成中点       
for(let i = 0 ;i < originCount ; i++){      
    let nexti = (i + 1) % originCount;  
    midpoints[i].x = (originPoint[i].x + originPoint[nexti].x)/2.0;  
    midpoints[i].y = (originPoint[i].y + originPoint[nexti].y)/2.0;  
}      
  
//平移中点  
let extrapoints = [];   
for(let i = 0 ;i < originCount ; i++){  
     let nexti = (i + 1) % originCount;  
     let backi = (i + originCount - 1) % originCount;  
     let midinmid;  
     midinmid.x = (midpoints[i].x + midpoints[backi].x)/2.0;  
     midinmid.y = (midpoints[i].y + midpoints[backi].y)/2.0;  
     let offsetx = originPoint[i].x - midinmid.x;  
     let offsety = originPoint[i].y - midinmid.y;  
     let extraindex = 2 * i;  
     extrapoints[extraindex].x = midpoints[backi].x + offsetx;  
     extrapoints[extraindex].y = midpoints[backi].y + offsety;  
     //朝 originPoint[i]方向收缩   
     let addx = (extrapoints[extraindex].x - originPoint[i].x) * scale;  
     let addy = (extrapoints[extraindex].y - originPoint[i].y) * scale;  
     extrapoints[extraindex].x = originPoint[i].x + addx;  
     extrapoints[extraindex].y = originPoint[i].y + addy;  
       
     let extranexti = (extraindex + 1)%(2 * originCount);  
     extrapoints[extranexti].x = midpoints[i].x + offsetx;  
     extrapoints[extranexti].y = midpoints[i].y + offsety;  
     //朝 originPoint[i]方向收缩   
     addx = (extrapoints[extranexti].x - originPoint[i].x) * scale;  
     addy = (extrapoints[extranexti].y - originPoint[i].y) * scale;  
     extrapoints[extranexti].x = originPoint[i].x + addx;  
     extrapoints[extranexti].y = originPoint[i].y + addy;  
       
}      
  
let controlPoint = [];  
//生成4控制点，产生贝塞尔曲线  
for(let i = 0 ;i < originCount ; i++){  
       controlPoint[0] = originPoint[i];  
       let extraindex = 2 * i;  
       controlPoint[1] = extrapoints[extraindex + 1];  
       let extranexti = (extraindex + 2) % (2 * originCount);  
       controlPoint[2] = extrapoints[extranexti];  
       let nexti = (i + 1) % originCount;  
       controlPoint[3] = originPoint[nexti];      
       let u = 1;  
       while(u >= 0){  
           let px = bezier3funcX(u,controlPoint);  
           let py = bezier3funcY(u,controlPoint);  
           //u的步长决定曲线的疏密  
           u -= 0.005;  
           let tempP = cvPoint(px,py);  
           //存入曲线点   
           curvePoint.push_back(tempP);  
       }      
}  
}

//三次贝塞尔曲线 
function bezier3funcX(uu, controlP){ 
let part0 = controlP[0].x * uu * uu * uu; 
let part1 = 3 * controlP[1].x * uu * uu * (1 - uu); 
let part2 = 3 * controlP[2].x * uu * (1 - uu) * (1 - uu); 
let part3 = controlP[3].x * (1 - uu) * (1 - uu) * (1 - uu); 
return part0 + part1 + part2 + part3; 
} 
function bezier3funcY(float uu,CvPoint *controlP){ 
let part0 = controlP[0].y * uu * uu * uu; 
let part1 = 3 controlP[1].y * uu * uu * (1 - uu); 
let part2 = 3 controlP[2].y * uu * (1 - uu) * (1 - uu); 
let part3 = controlP[3].y * (1 - uu) * (1 - uu) * (1 - uu); 
return part0 + part1 + part2 + part3; 
}

Answer 2

可以考虑用ajax、前台只需Js传参就OK、就让该方法在后台处理、非要搬去前台不麻烦么