c++ - 在 C++ 中传递对象会出现 'invalid use of non-static member' 错误

Question

所以，我正在制作一个游戏，当 throw 者(球)落在蹦床上时，我需要改变 throw 者的速度。我已经在 main 中有一个名为 detect_collision 的函数，它位于文件 main.cpp

中

所以，在蹦床类中，我有这个功能:

蹦床.cpp:

#include "trampoline.h"
#include "main.h"
#include "thrower.h"

//other functions

void Trampoline::landed(Thrower* thrower){
    if (detect_collision(this->bounding_box, thrower->bounding_box))
        thrower->speed.y = -2* thrower->speed.y;
  }

在 main.cpp 中:

#include "trampoline.h"
#include "main.h"
#include "thrower.h"

// other functions    

bool detect_collision(bounding_box_t a, bounding_box_t b) {
        return (abs(a.x - b.x) * 2 < (a.width + b.width)) &&
               (abs(a.y - b.y) * 2 < (a.height + b.height));
    }

编译时出现如下错误:

error: invalid use of non-static member function ‘bounding_box_t Trampoline::bounding_box()’
     if (detect_collision(this->bounding_box, thrower->bounding_box))
                                                                   ^

其他类似的问题没有多大帮助。

Answer 1

似乎您已将 thrower->bounding_box 定义为成员 function 而不是成员 variable。所以你需要将它用作thrower->bounding_box()

所以你的代码应该是

#include "trampoline.h"
#include "main.h"
#include "thrower.h"

//other functions

void Trampoline::landed(Thrower* thrower){
    if (detect_collision(this->bounding_box, thrower->bounding_box()))
        thrower->speed.y = -2* thrower->speed.y;
  }