Question

我需要帮助......拼命地。我正在制作游戏，我在函数apply_surface was not declared in this scope.中收到编译错误User::show() 错误在第95行。我不知道自己做错了什么。

编辑：现在它已经过了，图像＆＃34;阴茎＆＃34;，没有出现在屏幕上。抱歉编辑。

/*This source code copyrighted by Lazy Foo' Productions (2004-2013)
 and may not be redistributed without written permission.*/

//The headers
#include "SDL/SDL.h"
#include "SDL/SDL_image.h"
#include <string>

SDL_Surface *background = NULL;
SDL_Surface *screen = NULL;
SDL_Surface *penis = NULL;
SDL_Event event;

void cleanup()
{
    SDL_FreeSurface(background);
    SDL_FreeSurface(screen);
    SDL_FreeSurface(penis);
    SDL_Quit;
}

bool quit = false;

class User
{
private:
    SDL_Surface *penis = NULL;
    SDL_Surface *screen = NULL;
    int x;
    int y;
    int xVel;
    int yVel;
public:
    void keys();
    void move();
    void show();
    void user();
};
void User::keys()
{
    while(quit == false)
        if(SDL_PollEvent(&event))
        {
            if( event.type == SDL_QUIT )
                quit = true;
        }

    Uint8 *keystates = SDL_GetKeyState(NULL);


    if(keystates[SDLK_d] )
    {
        User::xVel+=50;
    }
    if(keystates[SDLK_a])
    {
        User::xVel-=50;
    }
    if(keystates[SDLK_s])
    {
        User::yVel+=50;
    }
    if(keystates[SDLK_w])
    {
        User::yVel-=50;
    }
    if(keystates[SDLK_ESCAPE])
    {
        cleanup();
    }
}

void User::user()
{
    x = 0;
    y = 0;
    xVel = 0;
    yVel = 0;
}

void User::move()
{
    x+=xVel;
    y+=yVel;
    x-=xVel;
}


void User::show()
{
    apply_surface(x,y,penis,screen);
    SDL_Flip( screen );
}

void apply_surface( int x, int y, SDL_Surface* source, SDL_Surface* destination )
{ //Temporary rectangle to hold the offsets

    SDL_Rect offset;
    //Get the offsets
    offset.x = x;
    offset.y = y; //Blit the surface
    SDL_BlitSurface( source, NULL, destination, &offset );
}



int main( int argc, char* argv[])
{
    SDL_Init(SDL_INIT_EVERYTHING);
    screen = SDL_SetVideoMode(640,400,32,SDL_SWSURFACE);
    background = IMG_Load("background.png");
    penis = IMG_Load("penis.png");
    apply_surface(0,0,background,screen);

    SDL_Flip(screen);

    while( quit == false )
    {
        User Penis;
        Penis.user();
        Penis.keys();
        Penis.move();
        Penis.show();
        if(quit == true)
        {
            cleanup();
        }        
    }
    return 0;
}

Answer 1

您的apply_surface()函数未在范围内声明

所以移动你的代码：

void apply_surface( int x, int y, SDL_Surface* source, SDL_Surface* destination )
{ //Temporary rectangle to hold the offsets

    SDL_Rect offset;
    //Get the offsets
    offset.x = x;
    offset.y = y; //Blit the surface
    SDL_BlitSurface( source, NULL, destination, &offset );
}

到顶部（在使用之前）

否则

在顶部添加一个函数原型，如下所示：

void apply_surface( int, int, SDL_Surface*, SDL_Surface*);

C ++错误，从函数调用类成员

1 个答案: