如何访问这个指针正确结构体？ [英] How do I access the pointer in this struct correctly?

问题描述

下面是2结构，然后使用它们很短的方法体的定义。
我不明白为什么编译器会引发错误：

  

physics.c：95：错误：不兼容的类型分配

cpBody 和 cpSpace 从外部库，这不是问题的一部分类型。

  typedef结构gameBody gameBody;结构gameBody
{
    cpBody *体;
    诠释numberOfShapes;
    cpShape * arrayOfShapes; //这个存储指针数组形状
};//结构体，它存储cpSpace对象和指针数组到主体对象
typedef结构游戏空间游戏空间;游戏空间结构
{
    cpSpace *空间;
    诠释numberOfObjects;
    gameBody * arrayOfObjects; //这个存储gameBodys数组
};无效physicsAddBody（*游戏空间空间，gameBody *身体，诠释objectIndex）
{
    gameBody *阵列=空间 - ＆GT; arrayOfObjects;
    数组[objectIndex] =身体; //这就是引发错误
}
 

解决方案

  

数组[objectIndex] =身体;

在左侧是一个 gameBody ，右侧一个 gameBody * 。

您尝试复制结构或做你想做的指针分配到一个指针数组？

Below are definitions for 2 structs, then a short method body that uses them. I don't understand why the compiler throws the error:

physics.c:95: error: incompatible types in assignment

cpBody and cpSpace are types from an external library, which isn't part of the problem.

typedef struct gameBody gameBody;

struct gameBody
{
    cpBody *body;
    int numberOfShapes;
    cpShape *arrayOfShapes; //This stores an array of pointers to Shapes
};

//Struct that stores the cpSpace object and the array of pointers to the body objects
typedef struct gameSpace gameSpace;

struct gameSpace
{ 
    cpSpace *space;
    int numberOfObjects;
    gameBody *arrayOfObjects;       //This stores an array of gameBodys
};

void physicsAddBody(gameSpace *space, gameBody *body, int objectIndex)
{
    gameBody *array = space -> arrayOfObjects;
    array[objectIndex] = body; //THIS IS WHERE THE ERROR IS THROWN
}

解决方案

array[objectIndex] = body;

On the left side is a gameBody, on the right side a gameBody*.

Do you try to copy the struct or do you want to assign the pointer into a pointer-array?

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