SDL做的一個簡單Button

#include "SDL.h"
#include "SDL_gfxPrimitives.h"

#define BMP_NAME "icon.bmp"
#define ICON "sample.bmp"
#define TITLE_NAME "TestSDL"
#define ICON_NAME  "My WinFrame"        //最小化icon的name
#define WIDTH  640
#define HEIGTH 480

static SDL_Surface *screen = NULL;

int Init()                      //初始化SDL
{
    if(SDL_Init(SDL_INIT_VIDEO) == -1)
    {
        fprintf(stderr,"SDL init error:%s",SDL_GetError());
        return -1;
    }
    return 0;
}

SDL_Surface *loadBMP(char *fileName)            //加載一個bmp位圖
{
    SDL_Surface *bmp;
    bmp = SDL_LoadBMP(fileName);
    if(bmp == NULL)
    {
        fprintf(stderr,"Could not load %s: %s\n",fileName,SDL_GetError());
        exit(1);
    }
    return bmp;
}

void creatScreen(int width , int height , int bpp , Uint32 flags)       //創建一個VideoMode
{
    screen = SDL_SetVideoMode(width , height,  bpp , flags);
    if(screen == NULL)
    {
        fprintf(stderr,"Could not Creat a Screen!:%s\n",SDL_GetError());
        exit(1);
    }
    return ;
}


int Destory(SDL_Surface *file)                  //釋放空間
{
    SDL_FreeSurface( file );
    return 0;
}

void show_bmp(SDL_Surface *bmp ,SDL_Rect *rect) //顯示bmp圖
{

    SDL_BlitSurface(bmp , NULL , screen , rect);
    SDL_UpdateRect(screen , 0 , 0 , 0 , 0 );
    return ;
}

void draw_button(SDL_Rect *button_rect , int flag)  //繪出BUTTON
{
    boxColor(screen, button_rect->x , button_rect->y ,button_rect->x + button_rect->w , button_rect->y + button_rect->h, 0xffffffff);
    if(flag == 1)
    {
        hlineColor( screen, button_rect->x , button_rect->x + button_rect->w ,button_rect->y + button_rect->h , 0x000000ff);
        vlineColor( screen, button_rect->x + button_rect->w , button_rect->y , button_rect->y + button_rect->h , 0x000000ff);
    }

    show_bmp( screen , &(screen->clip_rect) );
    return ;
}

int main(int argc,char **argv)
{

    const SDL_VideoInfo *info = NULL;
    int flag = 1;
    int width = WIDTH;
    int heigth = HEIGTH;
    int bpp = 0;

    SDL_Rect button_rect;

    Init();
    creatScreen(width , heigth, bpp , SDL_SWSURFACE);

    button_rect.x = ( screen->w / 2 )- 20;
    button_rect.y = ( screen->h / 2 )- 20;
    button_rect.w = 40;
    button_rect.h = 40;

    info = SDL_GetVideoInfo();
    if(info == NULL)
    {
        fprintf( stderr, "Video query failed: %s\n",SDL_GetError( ) );
        exit(1);

    }
    bpp = info->vfmt->BitsPerPixel ;            //獲得VideoMode的bpp

    SDL_WM_SetCaption(TITLE_NAME, ICON_NAME);               //設置窗體的NAME和ICON的NAME
    SDL_WM_SetIcon(loadBMP(ICON) , NULL);                       //加載ICON
    SDL_FillRect(screen, &(screen->clip_rect) , 0xaac9ff);
    draw_button(&button_rect , 0);

    SDL_Event event;
    while(flag)
    {
        while(SDL_PollEvent(&event))            //把事件加入事件隊列
        {
            switch(event.type)
            {
                case SDL_KEYDOWN:
                    if(event.key.keysym.sym == SDLK_ESCAPE)
                    {
                        flag = 0;
                    }

                    SDL_FillRect(screen, &(screen->clip_rect) , 0x00);          //填充screen
                    SDL_UpdateRect(screen , 0 , 0 , 0 , 0 );
                    break;
                case SDL_KEYUP:
                    printf("Key up......\n");
                    break;
                case SDL_MOUSEMOTION:

                    break;
                case SDL_MOUSEBUTTONDOWN:
                    printf("mouse: x = %d , y = %d\n",event.button.x,event.button.y);
                    if((event.button.x >= button_rect.x && event.button.x <= (button_rect.x + button_rect.w)) && (event.button.y >= button_rect.y && event.button.y <= ( button_rect.y + button_rect.h )))
                    {
                        draw_button(&button_rect , 1);
                    }

                    break;
                case SDL_MOUSEBUTTONUP:

                    draw_button(&button_rect , 0);
                    break;
                case SDL_QUIT:
                    printf("quit\n");
                    flag = 0;
                    break;
            }
        }
    }

    Destory(screen);
    SDL_Quit();
    return 0;
}