使用STL对2D数组排序

I have an array float points[keyCount][d]. d is a global variable, either 2 or 3. Additionally:

int axis = something // 0 or 1 -- depends on points stored in array

然后，我想使用类似以下内容的比较器对它们进行排序：

struct comp{
    int dim;
    comp(int dim){ this->dim = dim;}
    bool operator()(float* a, float* b){
        int otherDim = (dim + 1)%d;
        if(a[dim] < b[dim])
            return true;
        if(a[dim] > b[dim])
            return false;
        return a[otherDim] < b[otherDim];
    }
};

That is, use the variable axis to see which coordinate axis should be used to sort the points.

问题：

I tried sort function as:

sort(points, points + keyCount, comp(axis));

但这不起作用。

I also tried qsort, but wasn't able to figure out how to use the axis variable in that.

Also, note that I can't use vector or pair or array<>. Just the "normal" arrays. Is it possible to do this using STL?