c++ - C++ 中的“未命名类型”错误

Question

我有以下头文件:

#include <stdlib.h>
#include <stdio.h>
#include <string.h>
#include <stddef.h> 
#include <GL/glew.h>
#include <GL/glfw.h>
#include <glm/glm.hpp>
#include <glm/gtc/matrix_transform.hpp>
#include <glm/gtc/type_ptr.hpp>
#include <stdlib.h>
#include <vector>

class Sphere
{   
    public:
        Sphere();
        int count_sphere_vertices(int ,int, int);
        Vertex* create_sphere(int ,int , int);
};

现在，当我编译我的代码时，我得到了这个:

Sphere.h:18:3: error: ‘Vertex’ does not name a type
Sphere.cpp:48:1: error: ‘Vertex’ does not name a type

和

test_1.cpp: In function ‘int main()’: 
test_1.cpp:318:38: error: ‘class Sphere’ has no member named ‘create_sphere’

什么是

‘Vertex’ does not name a type

是什么意思？为什么我得到

‘class Sphere’ has no member named ‘create_sphere’

因为我的 Sphere.cpp 中有这个:

//Calculating points for the sphere (the algorithm is implemented here)
Vertex* Sphere::create_sphere(int dtheta,int dphi, int no_vertices)
{

    GLdouble x,y,z,x2,y2,z2;
    GLdouble magnitude=0;
    int n=-1;
    int theta,phi;
    const double PI = 3.1415926535897;
    GLdouble DTOR = (PI/180);//degrees to radians
    Vertex* sphere_vertices = new Vertex[no_vertices];


   for (theta=-90;theta<=90-dtheta;theta+=dtheta) {
      for (phi=0;phi<=360-dphi;phi+=dphi) {

    //calculating Vertex 1
     x = cos(theta*DTOR) * cos(phi*DTOR);
     y = cos(theta*DTOR) * sin(phi*DTOR);
         z = sin(theta*DTOR);

    n+=1;
    sphere_vertices[n].position[0] = x;
    sphere_vertices[n].position[1] = y;
    sphere_vertices[n].position[2] = z;


    //calculating Vertex 2
      x = cos((theta+dtheta)*DTOR) * cos(phi*DTOR);
      y = cos((theta+dtheta)*DTOR) * sin(phi*DTOR);
      z = sin((theta+dtheta)*DTOR);

    n+=1;
    sphere_vertices[n].position[0] = x;
    sphere_vertices[n].position[1] = y;
    sphere_vertices[n].position[2] = z;

     //calculating Vertex 3
     x = cos((theta+dtheta)*DTOR) * cos((phi+dphi)*DTOR);
     y = cos((theta+dtheta)*DTOR) * sin((phi+dphi)*DTOR);
     z = sin((theta+dtheta)*DTOR);

    n+=1;
    sphere_vertices[n].position[0] = x;
    sphere_vertices[n].position[1] = y;
    sphere_vertices[n].position[2] = z;

     //adding Vertex_1 again to divide the Quad into 2 triangles so it can be later filled with triangles!!!    
     //adding Vertex 1 again!
     x = cos(theta*DTOR) * cos(phi*DTOR);
     y = cos(theta*DTOR) * sin(phi*DTOR);
         z = sin(theta*DTOR);

     n+=1;
     sphere_vertices[n].position[0] = x;
     sphere_vertices[n].position[1] = y;
     sphere_vertices[n].position[2] = z;

        if (theta > -90 && theta < 90) {

            //calculating Vertex 4
            x = cos(theta*DTOR) * cos((phi+dphi)*DTOR);
            y = cos(theta*DTOR) * sin((phi+dphi)*DTOR);
            z = sin(theta*DTOR);

            n+=1;
            sphere_vertices[n].position[0] = x;
            sphere_vertices[n].position[1] = y;
            sphere_vertices[n].position[2] = z;

             }
        }
   }

   //Setting the color
    for(int i=0; i<no_vertices; i+=1)
    {
        sphere_vertices[i].color[0] = 1;
        sphere_vertices[i].color[1] = 0;
        sphere_vertices[i].color[2] = 0;
    }
    printf("%d >> \n", n);

    return sphere_vertices;
}

谢谢

编辑:这包含在我的“主要”方法所在的 test_1.cpp 中。

#include "Sphere.h"
#include "Terrain.h"

using namespace std;

//Vertex Structure
struct Vertex {

    GLdouble position[3];
    GLfloat color[3];
    GLfloat texture[2];
};

然后我像这样创建一个球体

 sphere_vertices_final = planet_1->create_sphere(5,5,no_sphere_vertices);

我应该如何在 Sphere.h 文件中包含 Vertex？

Answer 1

这意味着编译器不知道什么是Vertex。它未在您包含的任何头文件中定义(或未正确定义)。因此，试图返回一个指针的函数也不能被编译。

因为您只在头文件中处理指向 Vertex 的指针，所以您可以转发声明该类:

class Vertex;

class Sphere
{   
    public:
      // ...

...但是，在访问类的任何方法或其他成员之前，您必须在 cpp 文件中包含正确的定义。