所以我基本上按照Shaun Mitchell的一本名为SDL游戏开发的书。 我是第58页的最新信息，它告诉我们如何实现多态性。
到目前为止，我所拥有的是：
- 创建我们进行所有渲染更新等的主代码（Game.cpp和Game.h）
- 创建纹理管理器作为单例（TextureManager.h和TextureManager.cpp）
- 创建GameObject（GameObject.h和GameObject.cpp）
- 创建一个继承GameObject（Player.h和Player.cpp）的播放器
所以我的GameObject类基本上有3种方法：加载，绘制和更新。 加载基本上加载图像，我使用我的TextureManager来执行此操作。 绘制它并更新只是改变它的位置和当前帧。
我传递了图像的名称，它基本上是我称之为Game类的目录，渲染器和textureID。
基本上问题是我将两个不同的目录传递给GameObject 和一个播放器，但它只加载我传入的最后一个目录。因为GameObject和Player都变成了同一个图像。
所以我认为问题在于Game类，Player类或GameObject类。 我在Game类中创建了对象，并在init.c函数中将它们传递到了Game.cpp中 在哪里说
m_go->load(100, 100, 96, 60, "assets/simba.bmp", "animate",m_pRenderer);
m_player->load(300, 300, 96, 60, "assets/download.bmp", "animate",m_pRenderer);
GameObject.h
#ifndef GAMEOBJECT_H
#define GAMEOBJECT_H
#include <string>
#include <iostream>
#include "SDL_image.h"
#include "TextureManager.h"
class GameObject
{
public:
virtual bool load(int x, int y, int width, int height, std::string name, std::string textureID, SDL_Renderer* pRenderer);
virtual void draw(SDL_Renderer* pRenderer);
virtual void update();
virtual void clean();
protected:
std::string m_textureID;
int m_currentFrame;
int m_currentRow;
int m_x;
int m_y;
int m_width;
int m_height;
};
#endif // GAMEOBJECT_H
GameObject.cpp
#include "GameObject.h"
bool GameObject::load(int x, int y, int width, int height, std::string name, std::string textureID, SDL_Renderer* pRenderer)
{
m_x = x;
m_y = y;
m_width = width;
m_height = height;
m_textureID = textureID;
m_currentRow = 1;
m_currentFrame = 1;
if(!TextureManager::Instance()->load(name, textureID, pRenderer))
{
return false;
}
return true;
}
void GameObject::draw(SDL_Renderer* pRenderer)
{
TextureManager::Instance()->drawFrame(m_textureID, m_x, m_y,m_width, m_height, m_currentRow, m_currentFrame, pRenderer);
}
void GameObject::update()
{
m_x += 1;
m_currentFrame = int(((SDL_GetTicks() / 100) % 6));
}
void GameObject::clean()
{
}
在我的Player类中，我做同样的事情，除了我使用已经在GameObject中创建的方法
Player.h
#ifndef PLAYER_H
#define PLAYER_H
#include "GameObject.h"
class Player : public GameObject
{
public:
bool load(int x, int y, int width, int height, std::string name, std::string textureID, SDL_Renderer* pRenderer);
void draw(SDL_Renderer* pRenderer);
void update();
void clean();
};
#endif // PLAYER_H
Player.cpp
#include "Player.h"
bool Player::load(int x, int y, int width, int height, std::string name, std::string textureID, SDL_Renderer* pRenderer)
{
if(!GameObject::load(x, y, width, height, name, textureID, pRenderer))
{
return false;
}
return true;
}
void Player::draw(SDL_Renderer* pRenderer)
{
GameObject::draw(pRenderer);
}
void Player::update()
{
m_currentFrame = int(((SDL_GetTicks() / 100) % 6));
m_x -= 1;
}
void Player::clean()
{
}
这是图像不会在Game.cpp中加载相同内容的部分 所以我基本上创建了一个包含GameObjects的向量，它告诉我使用它，以便每当我想绘制对象时我只能循环遍历它
Game.h
#ifndef GAME_H
#define GAME_H
#include <SDL.h>
#include <SDL_image.h>
#include <string.h>
#include <iostream>
#include <vector>
#include "TextureManager.h"
#include "Player.h"
class Game
{
public:
Game() {}
~Game() {}
bool init(const char* title, int xpos, int ypos, int width, int height, int flags);
void render();
void update();
void handleEvents();
void clean();
// a function to access the private running variable
bool running() { return m_bRunning; }
private:
SDL_Window* m_pWindow;
SDL_Renderer* m_pRenderer;
int m_currentFrame;
bool m_bRunning;
GameObject* m_go;
GameObject* m_player;
std::vector<GameObject*> m_gameObjects;
};
#endif
Game.cpp
#include "Game.h"
typedef TextureManager TheTextureManager; // Singleton TextureManager
Game* g_game = 0; // Game Object
bool Game::init(const char* title, int xpos, int ypos, int width,int height, int flags)
{
// attempt to initialize SDL
if(SDL_Init(SDL_INIT_EVERYTHING) == 0)
{
std::cout << "SDL init success\n";
// init the window
m_pWindow = SDL_CreateWindow(title, xpos, ypos,width, height, flags);
if(m_pWindow != 0) // window init success
{
std::cout << "window creation success\n";
m_pRenderer = SDL_CreateRenderer(m_pWindow, -1, 0);
if(m_pRenderer != 0) // renderer init success
{
std::cout << "renderer creation success\n";
SDL_SetRenderDrawColor(m_pRenderer,255,255,255,255);
}
else
{
std::cout << "renderer init fail\n";
return false; // renderer init fail
}
}
else
{
std::cout << "window init fail\n";
return false; // window init fail
}
}
else
{
std::cout << "SDL init fail\n";
return false; // SDL init fail
}
std::cout << "init success\n";
m_go = new GameObject();
m_player = new Player();
m_go->load(100, 100, 96, 60, "assets/simba.bmp", "animate",m_pRenderer);
m_player->load(300, 300, 96, 60, "assets/download.bmp", "animate",m_pRenderer);
m_gameObjects.push_back(m_go);
m_gameObjects.push_back(m_player);
m_bRunning = true; // everything inited successfully, start the main loop
return true;
}
void Game::render()
{
SDL_RenderClear(m_pRenderer); // clear the renderer to the draw color
//m_go.draw(m_pRenderer);
//m_player.draw(m_pRenderer);
for(std::vector<GameObject*>::size_type i = 0; i != m_gameObjects.size(); i++)
{
m_gameObjects[i]->draw(m_pRenderer);
}
SDL_RenderPresent(m_pRenderer); // draw to the screen
}
void Game::clean()
{
std::cout << "cleaning game\n";
SDL_DestroyWindow(m_pWindow);
SDL_DestroyRenderer(m_pRenderer);
SDL_Quit();
}
void Game::handleEvents()
{
SDL_Event event;
if(SDL_PollEvent(&event))
{
switch (event.type)
{
case SDL_QUIT:
m_bRunning = false;
break;
default:
break;
}
}
}
void Game::update()
{
//m_currentFrame = int(((SDL_GetTicks() / 100) % 6));
//m_go.update();
//m_player.update();
for(std::vector<GameObject*>::size_type i = 0; i != m_gameObjects.size(); i++)
{
m_gameObjects[i]->update();
}
}
int main(int argc, char* argv[])
{
g_game = new Game();
g_game->init("Chapter 1", 100, 100, 640, 480, 0);
while(g_game->running())
{
g_game->render();
g_game->handleEvents();
g_game->update();
SDL_Delay(10); // add the delay
}
g_game->clean();
return 0;
}
正如你在init函数结束时看到的那样，我有m_go加载simba，m_player加载下载。即使它们向不同的方向移动（GameObject向右移动，播放器向左移动，如更新方法中的类所示）。
我的程序只为两者加载下载。
我不确定TextureManager类是否相关，但我还是会发布它 TextureManager.h
#ifndef TEXTUREMANAGER_H
#define TEXTUREMANAGER_H
#include <SDL.h>
#include <SDL_image.h>
#include <string.h>
#include <iostream>
#include <map>
class TextureManager
{
public:
bool load(std::string fileName,std::string id,SDL_Renderer* pRenderer);
void draw(std::string id, int x, int y, int width, int height, SDL_Renderer* pRenderer, SDL_RendererFlip flip = SDL_FLIP_NONE);
void drawFrame(std::string id, int x, int y, int width, int height, int currentRow, int currentFrame, SDL_Renderer* pRenderer, SDL_RendererFlip flip = SDL_FLIP_NONE);
std::map <std::string, SDL_Texture*> m_textureMap;
static TextureManager* Instance()
{
if(s_pInstance == 0)
{
s_pInstance = new TextureManager();
return s_pInstance;
}
return s_pInstance;
}
//typedef TextureManager TheTextureManager;
protected:
private:
TextureManager(){}
static TextureManager* s_pInstance;
};
#endif // TEXTUREMANAGER_H
TextureManager.cpp
#include "TextureManager.h"
TextureManager* TextureManager::s_pInstance = 0;
bool TextureManager::load(std::string fileName, std::string id, SDL_Renderer* pRenderer)
{
SDL_Surface* pTempSurface = IMG_Load(fileName.c_str());
if(pTempSurface == 0)
{
return false;
}
SDL_Texture* pTexture =
SDL_CreateTextureFromSurface(pRenderer, pTempSurface);
SDL_FreeSurface(pTempSurface);
// everything went ok, add the texture to our list
if(pTexture != 0)
{
m_textureMap[id] = pTexture;
return true;
}
// reaching here means something went wrong
return false;
}
void TextureManager::draw(std::string id, int x, int y, int width, int height, SDL_Renderer* pRenderer, SDL_RendererFlip flip)
{
SDL_Rect srcRect;
SDL_Rect destRect;
srcRect.x = 0;
srcRect.y = 0;
srcRect.w = destRect.w = width;
srcRect.h = destRect.h = height;
destRect.x = x;
destRect.y = y;
SDL_RenderCopyEx(pRenderer, m_textureMap[id], &srcRect,
&destRect, 0, 0, flip);
}
void TextureManager::drawFrame(std::string id, int x, int y, int width, int height, int currentRow, int currentFrame, SDL_Renderer *pRenderer, SDL_RendererFlip flip)
{
SDL_Rect srcRect;
SDL_Rect destRect;
srcRect.x = width * currentFrame;
srcRect.y = height * (currentRow - 1);
srcRect.w = destRect.w = width;
srcRect.h = destRect.h = height;
destRect.x = x;
destRect.y = y;
SDL_RenderCopyEx(pRenderer, m_textureMap[id], &srcRect,
&destRect, 0, 0, flip);
}
答案 0 :(得分：0)
您正在使用＆＃34; animate＆＃34; textureID不止一次 - 这需要是唯一的
您的密码：
m_go->load(100, 100, 96, 60, "assets/simba.bmp", "animate", m_pRenderer);
m_player->load(300, 300, 96, 60, "assets/download.bmp", "animate", m_pRenderer)
纹理被加载会发生什么，但它会覆盖现有的纹理，该纹理具有＆＃34; animate＆＃34;键入地图。使它们独一无二，这应该可以解决您的问题。