C++ SFML Sprite 未绘制，但未发生错误

Question

我一直在尝试使用类在 C++ SFML 中制作 Sprite 显示。但是，当我编译并运行该程序时，什么也没有出现:也没有错误。

(main 中唯一发生的事情是创建了一个“游戏”对象)

游戏.h

    #ifndef GAME_H
    #define GAME_H
    #include <SFML/Graphics.hpp>
    #include "Player.h"
    
    
    class Game
    {
        public:
            Game();
        private:
            //Variables
            sf::RenderWindow _mainWindow;
            enum _gameState { Playing, Paused, Splash, Menu };
    
            //Methods
            void gameLoop();
    };
    
    #endif // GAME_H

游戏.cpp

#include "Game.h"
#include "Player.h"

Game::Game() {

    //Variables
    _mainWindow.create(sf::VideoMode(960, 640), "Game", sf::Style::Titlebar | sf::Style::Close);
    _mainWindow.setFramerateLimit(60);

   //Start Game Loop
    gameLoop();

}

void Game::gameLoop() {

    Player player;

    while(_mainWindow.isOpen()) {

        sf::Event ev;
        while(_mainWindow.pollEvent(ev)) {
            if(ev.type == sf::Event::Closed)
                _mainWindow.close();
            if(ev.type == sf::Event::KeyPressed) {
                if(ev.key.code == sf::Keyboard::Escape)
                    _mainWindow.close();
            }
        }


        //Draw Stuff
        _mainWindow.clear(sf::Color::White);
        player.drawSprite(_mainWindow);
        _mainWindow.display();

    }

}

Player.h

#ifndef PLAYER_H
#define PLAYER_H
#include <SFML/Graphics.hpp>
#include <iostream>


class Player
{
    public:
        Player();
        void drawSprite(sf::RenderWindow& window);
    private:
        bool loadSprite();
        sf::Texture _playerTexture;
        sf::Sprite _playerSprite;
};

#endif // PLAYER_H

Player.cpp

#include "Player.h"
#include "Game.h"


Player::Player()
{
    if(!Player::loadSprite()){
        return;
    }
}

bool Player::loadSprite() {

    sf::Texture _playerTexture;
    if(!_playerTexture.loadFromFile("img/darkguy.png", sf::IntRect(32,32,32,32))) {
        std::cout << "Failed to load player image" << std::endl;
        return false;
    } else {
        sf::Sprite _playerSprite;
        _playerSprite.setTexture(_playerTexture);
    }

    return true;
}

void Player::drawSprite(sf::RenderWindow& window) {

    //sprite.setTextureRect(sf::IntRect(10, 10, 32, 32));
    window.draw(_playerSprite);
    std::cout << "Sprite Drawn Successfully" << std::endl;

}

Answer 1

您在这里声明了一个新的本地 _playerSprite:

} else {
    sf::Sprite _playerSprite;
    _playerSprite.setTexture(_playerTexture);
}

相反，使用现有的类成员:

} else {
    _playerSprite.setTexture(_playerTexture);
}

您可能还想删除此代码的第一行，同样的问题:

bool Player::loadSprite() 
{
    sf::Texture _playerTexture; // <--- local redeclaration