c中typedef结构中的函数指针

Question

I have been working on this code and keep coming across a segmentation fault. I am almost positive that it is coming from how I initialized my function point in the OBJ_T type. Here's what I have:

typedef struct obj
{
    COLOR_T color;
    int (*intersect)(RAY_T ray, struct obj, VP_T *int_pt, VP_T *normal, double *t);

    union geom
    {
       SPHERE_T sphere;
       PLANE_T plane;
    }geom;

} OBJ_T;

This is the line I get the seg fault:

if((*(objs[i].intersect))(ray, objs[i], &int_pt, &normal, &t) == 1)

Answer 1

if((*(objs[i].intersect))(ray, objs[i], &int_pt, &normal, &t) == 1)

The memory is not allocated for that pointer that time you will get the segmentation fault.

To solve this, fist you have to allocate the memory for the structure member.

int (*intersect)(RAY_T ray, struct obj, VP_T *int_pt, VP_T *normal, double t);