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我一直在使用SDL2.0和C++进行这个游戏，并且遇到了麻烦。我创建了移动功能并调用了正确的矩形。并且已经在主循环中调用移动功能，并且它不移动。SDL2.0移动雪碧键盘
这是代码。
//
// Window.cpp
// Galaxy Shooter
//
// Created by Samrith on 02/03/14.
// Copyright (c) 2014 Sam Shankar. All rights reserved.
//
#include "Window.h"
void Window::create() {
Resources r;
SDL_Init(SDL_INIT_EVERYTHING);
window = SDL_CreateWindow("Galaxy Shooter", SDL_WINDOWPOS_UNDEFINED, SDL_WINDOWPOS_UNDEFINED, SCREEN_WIDTH, SCREEN_HEIGHT, SDL_WINDOW_SHOWN);
screen = SDL_GetWindowSurface(window);
if(window == NULL)
std::cout << " Window cannot be created. Error: " << SDL_GetError();
else {
r.load();
SDL_UpdateWindowSurface(window);
}
}
void Window::destroy() {
Resources r;
SDL_DestroyWindow(window);
r.free();
SDL_Quit();
}
void Window::run() {
bool done = false;
Resources r;
create();
while(!done)
{
while(SDL_PollEvent(&event) != 0)
{
if(event.type == SDL_QUIT)
{
done = true;
destroy();
}
r.move(event); //This is the move function
SDL_UpdateWindowSurface(window);
}
r.projectile();
SDL_UpdateWindowSurface(window);
}
}
SDL_Window * Window::getWindow() {
return window;
}
SDL_Surface * Window::getSurface() {
return screen;
}
这里是资源源文件，其中包含了移动功能：
//
// Resources.cpp
// Galaxy Shooter
//
// Created by Samrith on 06/03/14.
// Copyright (c) 2014 Sam Shankar. All rights reserved.
//
#include "Resources.h"
bool b[4] = {0, 0, 0, 0};
void Resources::load() {
background();
rocket();
//r.create();
}
void Resources::free() {
Sound s;
SDL_FreeSurface(bgimage);
SDL_FreeSurface(rimage);
//SDL_FreeSurface(screen);
s.destroy();
}
//void Resources::run() {
// Window w;
// w.run();
//}
void Resources::background() {
Window w;
Sound s;
//Load screen
screen = SDL_GetWindowSurface(w.getWindow());
if(screen == NULL)
std::cout << "Surface (background) error: " << SDL_GetError();
//Load image
bgimage = IMG_Load("bg2.jpg");
if(bgimage == NULL)
std::cout << "Image (background) error: " << SDL_GetError();
//Load rectangle and set values
bgrect.x = 0;
bgrect.y = 0;
bgrect.h = w.screenH();
bgrect.w = w.screenW();
//Blit image to screen
SDL_BlitScaled(bgimage, NULL, screen, &bgrect);
s.init(1);
}
void Resources::rocket() {
Window w;
Sound s;
//Load screen
screen = SDL_GetWindowSurface(w.getWindow());
if(screen == NULL)
std::cout << "Surface (rocket) error: " << SDL_GetError();
//Load image
rimage = IMG_Load("rocket.png");
if(rimage == NULL)
std::cout << "Image (rocket) error: " << SDL_GetError();
//Load rectangle and set values
rrect.x = 15;
rrect.y = w.screenH()/2;
rrect.h = 75;
rrect.w = 75;
//Blit image to screen
SDL_BlitScaled(rimage, NULL, screen, &rrect);
//s.init(2);
}
void Resources::move(SDL_Event event) {
//bool done = false;
Window w;
switch(event.type)
{
case SDL_KEYDOWN:
switch(event.key.keysym.sym)
{
case SDLK_UP:
b[0] = 1; break;
case SDLK_DOWN:
b[1] = 1; break;
case SDLK_RIGHT:
b[2] = 1; break;
case SDLK_LEFT:
b[3] = 1; break;
}
break;
case SDL_KEYUP:
switch(event.key.keysym.sym)
{
case SDLK_UP:
b[0] = 0; break;
case SDLK_DOWN:
b[1] = 0; break;
case SDLK_RIGHT:
b[2] = 0; break;
case SDLK_LEFT:
b[3] = 0; break;
}
break;
}
if(b[0]==true)
rrect.y += 10;
if(b[1]==true)
rrect.y -= 10;
if(b[2]==true)
rrect.x += 10;
if(b[3]==true)
rrect.x -= 10;
}
void Resources::projectile() {
Window w;
SDL_PumpEvents();
int x, y;
SDL_GetMouseState(&x, &y);
if(SDL_GetMouseState(&x, &y) & SDL_BUTTON(1))
{
rrect.x = x;
rrect.y = y;
SDL_BlitScaled(rimage, NULL, screen, &rrect);
for(int i=rrect.x; i<=w.screenW(); i++)
rrect.x+=2;
}
}
另外，我用Google搜索这个问题，并尝试了各种教程和文档。这是我最后的选择，而不是我转向这个问题的第一位。所以请善待。 :)
在我看来，你的问题是你声明资源r;在每个函数的堆栈中。例如，当你调用'void Window :: create（）'时，你声明r并加载它加载的任何东西，但是一旦函数返回r就会被销毁。所以你在运行时声明的r永远不会调用它的load（）函数。 – Hjorthenify
@Hjorthenify我明白你的意思。所以我应该理想地创建一个全局函数并在整个函数中使用它，以确保它不会超出范围？ – Sam
全局变量被认为是不好的做法，你应该把它变成你的窗口类的成员变量。 – Hjorthenify