SDL+C简单游戏例子

#include <SDL.h> #include <stdio.h> #define NUM_SOUNDS 2 struct sample { Uint8 *data; Uint32 dpos; Uint32 dlen; } sounds[NUM_SOUNDS]; //this is callback function,it is executed in separate thread. void mixaudio(void *unused, Uint8 *stream, int len) { int i; Uint32 amount; for ( i=0; i<len ) { amount = len; } //convert original sound data from wav file to destnation format SDL_MixAudio(stream, &sounds.data[sounds.dpos], amount, SDL_MIX_MAXVOLUME); sounds.dpos += amount; } int Open_Audio() { SDL_AudioSpec fmt; //open audio device and set properties fmt.freq = 22050; fmt.format = AUDIO_S16; fmt.channels = 2; fmt.samples = 512; fmt.callback = mixaudio; fmt.userdata = NULL; if ( SDL_OpenAudio(&fmt, NULL) < 0 ) { debug("无法打开音频： %s＼n", SDL_GetError()); return -1; } //begin play SDL_PauseAudio(0); } void PlaySound(char *file) { int index; SDL_AudioSpec wave; Uint8 *data; Uint32 dlen; SDL_AudioCVT cvt; //find an empty sound port for ( index=0; index<NUM_SOUNDS; ++index ) { if ( sounds[index].dpos == sounds[index].dlen ) { break; } } if ( index == NUM_SOUNDS ) return; //load wav file, and copy sound data to buffer if ( SDL_LoadWAV(file, &wave, &data, &dlen) == NULL ) { debug("call SDL_LoadWAV failed＼n"); return; } //build audio convertion struct SDL_BuildAudioCVT(&cvt, wave.format, wave.channels, wave.freq,AUDIO_S16, 2,22050); //build cvt.buf, and copy sound data to this buffer,then free sound data buffer cvt.buf = (Uint8 *)malloc(dlen*cvt.len_mult); memcpy(cvt.buf, data, dlen); cvt.len = dlen; SDL_ConvertAudio(&cvt); SDL_FreeWAV(data); //free history sound buffer,it is equal to cvt.buf if ( sounds[index].data ) { free(sounds[index].data); } //protect resource which will be used in thread mixaudio SDL_LockAudio(); sounds[index].data = cvt.buf; sounds[index].dlen = cvt.len_cvt; sounds[index].dpos = 0; SDL_UnlockAudio(); //open audio to play Open_Audio(); } //用键盘控制精灵移动 int main(int argc, char ** argv) { SDL_Surface * screen; //主表面 SDL_Surface * image; //用来放MM-----的图片信息(像素) SDL_Surface * PlayerImage; //用来测试的图片 SDL_Event event; Uint32 BeginTicks, EndTicks; SDL_Rect PRect, BRect; //PRect对应精灵的移动的小图位置（实现动画），BRect对应精灵在屏幕的位置。 unsigned char PlayerStarts = 0; unsigned char PlayerIndex = 0; bool bAppRun = true; //初始化SDL if (SDL_Init(SDL_INIT_VIDEO | SDL_INIT_TIMER) == -1) { fprintf(stderr, "SDL_Init %s\n", SDL_GetError()); return -1; } //初始化成功设置退出要调用的函数SDL_Quit atexit(SDL_Quit); //创建一个640X480 16-bit 模式的主表面 16位可以让MM的效果好看一点 screen = SDL_SetVideoMode(230, 230, 16, SDL_SWSURFACE); if (screen == NULL) { fprintf(stderr, "Couldn't set 640x480x8 video mode %s\n", SDL_GetError()); return -1; } //读取MM图片信息，并创建一个表面，并把数据填入该表面中。 image = SDL_LoadBMP("./mm.bmp"); //请在终端里运行该程序 if (image == NULL) { fprintf(stderr, "Couldn't load MM, %s\n", SDL_GetError()); //遗憾你不能显示MM了,不过你可以用图片浏览程序看。 return -1; } //读取player.bmp PlayerImage = SDL_LoadBMP("./player.bmp"); //请在终端里运行该程序 if (image == NULL) { fprintf(stderr, "Couldn't load MM, %s\n", SDL_GetError()); //遗憾你不能显示MM了,不过你可以用图片浏览程序看。 return -1; } //读取第一个像素 Uint8 key = *((Uint8 *)PlayerImage->pixels); //设置色键 SDL_SetColorKey(PlayerImage, SDL_SRCCOLORKEY, key); //有了MM的表面了，就可以显示了。 //将MM的表面画在我们的主表面上,用MM来作为背景 if (SDL_BlitSurface(image, NULL, screen, NULL) < 0) { //解释一下NULL，第一个是按照image的尺寸显示，第二个是默认显示。你也可以指定大小，不过要用到SDL_Rect你可以看一看帮助。 fprintf(stderr, "BlitSurface error: %s\n", SDL_GetError()); //看看提示吧 return -1; } PRect.x = 0; //初始化动画显示的图片。 PRect.y = 0; PRect.w = 32; PRect.h = 48; BRect.x = 0; //初始化精灵的位置。 BRect.y = 0; BRect.w = 32; BRect.h = 48; //贴上测试用的表面 if (SDL_BlitSurface(PlayerImage, &PRect, screen, &BRect) < 0) { fprintf(stderr, "BlitSurface error: %s\n", SDL_GetError()); //看看提示吧 return -1; } //好了更新显示画出MM SDL_UpdateRect(screen, 0, 0, image->w, image->h); BeginTicks = SDL_GetTicks(); while (bAppRun) { //消息循环 if (SDL_PollEvent(&event)) { switch (event.type) { case SDL_KEYDOWN: switch (event.key.keysym.sym) { case SDLK_ESCAPE: bAppRun = false; //按下了ESC退出程序。 break; case SDLK_UP: PlayerStarts = 1; //向上移动。 PlayerIndex = 0; //动画序号清零 break; case SDLK_DOWN: PlayerStarts = 2; //向下移动。 PlayerIndex = 0; //动画序号清零 break; case SDLK_LEFT: PlayerStarts = 3; //向左移动 PlayerIndex = 0; //动画序号清零 break; case SDLK_RIGHT: PlayerStarts = 4; //向右移动 PlayerIndex = 0; //动画序号清零 break; } break; case SDL_KEYUP: PlayerStarts = 0; //按键松开。停止切换动画。 break; case SDL_QUIT: bAppRun = false; break; } } EndTicks = SDL_GetTicks(); if ((EndTicks - BeginTicks) > 50) { //到了50MS BeginTicks = EndTicks; SDL_FillRect(screen, &BRect, 0); //清除以前的图片。 if (PlayerStarts) { switch (PlayerStarts) { case 1: //向上移动。 if ((BRect.y - 5) > 0) { //要移动的位置是否到顶 BRect.y -= 5; //坐标减去5 } else { BRect.y = 0; //设置位置在顶部。 } PRect.x = PlayerIndex * 32; //使用序号计算该显示那个动画图片 PRect.y = 144; //向上的图组 PlayerIndex ++; //动画序号加1 if (PlayerIndex > 2) PlayerIndex = 0; //循环显示动画 break; case 2: //以下请大家自己分析。 if ((BRect.y + BRect.h + 5) < screen->h) { BRect.y += 5; } else { BRect.y = screen->h - BRect.h; } PRect.x = PlayerIndex * 32; PRect.y = 0; PlayerIndex ++; if (PlayerIndex > 2) PlayerIndex = 0; break; case 3: if ((BRect.x - 5) > 0) { BRect.x -= 5; } else { BRect.x = 0; } PRect.x = PlayerIndex * 32; PRect.y = 48; PlayerIndex ++; if (PlayerIndex > 2) PlayerIndex = 0; break; case 4: if ((BRect.x + BRect.w + 5) < screen->w) { BRect.x += 5; } else { BRect.x = screen->w - BRect.w; } PRect.x = PlayerIndex * 32; PRect.y = 96; PlayerIndex ++; if (PlayerIndex > 2) PlayerIndex = 0; break; } } if (SDL_BlitSurface(image, NULL, screen, NULL) < 0) { //解释一下NULL，第一个是按照image的尺寸显示，第二个是默认显示。你也可以指定大小，不过要用到SDL_Rect你可以看一看帮助。 fprintf(stderr, "BlitSurface error: %s\n", SDL_GetError()); //看看提示吧 return -1; } //贴上测试用的表面 if (SDL_BlitSurface(PlayerImage, &PRect, screen, &BRect) < 0) { fprintf(stderr, "BlitSurface error: %s\n", SDL_GetError()); //