C语言实现数字雨效果

#include <windows.h>#include <windowsx.h>#define ID_TIMER  1#define STRMAXLEN 25 //一个显示列的最大长度#define STRMINLEN 8 //一个显示列的最小长度LRESULT CALLBACK WndProc (HWND, UINT, WPARAM, LPARAM) ;////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////typedef struct tagCharChain //整个当作屏幕的一个显示列,这是个双向列表{    struct tagCharChain *prev; //链表的前个元素    TCHAR ch;         //一个显示列中的一个字符    struct tagCharChain *next; //链表的后个元素}CharChain, *pCharChain;typedef struct tagCharColumn{    CharChain *head, *current, *point;    int x, y, iStrLen; //显示列的开始显示的x,y坐标,iStrLen是这个列的长度    int iStopTimes, iMustStopTimes; //已经停滞的次数和必须停滞的次数,必须停滞的次数是随机的}CharColumn, *pCharColumn;int WINAPI WinMain(HINSTANCE hInstance, HINSTANCE hPrevInstance,          PSTR szCmdLine, int iCmdShow){    static TCHAR szAppName[] = TEXT ("matrix") ;    HWND      hwnd ;    MSG      msg ;    WNDCLASS  wndclass ;    wndclass.style        = CS_HREDRAW | CS_VREDRAW ; // class style    wndclass.lpfnWndProc    = WndProc ;    wndclass.cbClsExtra    = 0 ;    wndclass.cbWndExtra    = 0 ;    wndclass.hInstance    = hInstance ;    wndclass.hIcon        = LoadIcon (NULL, IDI_APPLICATION) ;    wndclass.hCursor    = LoadCursor (NULL, IDC_ARROW) ;    wndclass.hbrBackground    = (HBRUSH) GetStockObject (BLACK_BRUSH) ;    wndclass.lpszMenuName    = NULL ;    wndclass.lpszClassName    = szAppName ;    if(!RegisterClass (&wndclass))    {      MessageBox (NULL, TEXT ("此程序必须运行在NT下!"), szAppName, MB_ICONERROR) ;      return 0;    }    hwnd = CreateWindow (szAppName, NULL,              WS_DLGFRAME | WS_THICKFRAME | WS_POPUP, // windows style              0, 0,              GetSystemMetrics(SM_CXSCREEN), GetSystemMetrics(SM_CYSCREEN),              NULL, NULL, hInstance,              NULL) ;    ShowWindow (hwnd, SW_SHOWMAXIMIZED) ; //最大化显示 show windows    UpdateWindow (hwnd) ;    ShowCursor(FALSE); //隐藏鼠标光标        srand ((int) GetCurrentTime ()) ; //初始化随机数发生器    while (GetMessage (&msg, NULL, 0, 0))    {      TranslateMessage (&msg) ;      DispatchMessage (&msg) ;    }    ShowCursor(TRUE); //显示鼠标光标    return msg.wParam ;}TCHAR randomChar() //随机字符产生函数{    return (TCHAR)(rand()%(126-33)+33); //33到126之间}int init(CharColumn *cc, int cyScreen, int x) //初始化{    int j;    cc->iStrLen = rand()%(STRMAXLEN-STRMINLEN) + STRMINLEN; //显示列的长度    cc->x = x+3 ;    //显示列的开始显示的x坐标    cc->y =rand()%3?rand()%cyScreen:0; //显示列的开始显示的y坐标    cc->iMustStopTimes = rand()%6 ;    cc->iStopTimes  = 0 ;    cc->head = cc->current =            (pCharChain)calloc(cc->iStrLen, sizeof(CharChain)); //生成显示列    for(j=0; j<cc->iStrLen-1; j++)    {        cc->current->prev = cc->point; //cc->point一个显示列的前个元素        cc->current->ch = '/0';        cc->current->next = cc->current+1; //cc->current+1一个显示列的后个元素        cc->point     = cc->current++; //cc->point = cc->current; cc->current++;    }    cc->current->prev = cc->point; //最后一个节点    cc->current->ch = '/0';    cc->current->next = cc->head;    cc->head->prev  = cc->current; //头节点的前一个为此链的最后一个元素    cc->current = cc->point = cc->head; //free掉申请的内存要用current当参数    cc->head->ch = randomChar(); // 对链表头的 元素填充    return 0;}LRESULT CALLBACK WndProc (HWND hwnd, UINT message, WPARAM wParam, LPARAM lParam){   HDC   hdc ;   //ctn 用来确定一个显示链是否 向下前进,如果等待次数超过必须等待的次数,ctn就代表要向下前进   int i, j, temp, ctn; //j为一个显示链中除链表头外的在屏幕上显示的y坐标,temp绿色过度到黑色之用   static HDC hdcMem;   HFONT  hFont;   static HBITMAP hBitmap;   static int cxScreen, cyScreen; //屏幕的宽度 高度.   static int iFontWidth=10, iFontHeight=15, iColumnCount; //字体的宽度 高度, 列数   static CharColumn *ccChain;   switch (message)   {    case WM_CREATE:      cxScreen = GetSystemMetrics(SM_CXSCREEN) ; //屏幕宽度      cyScreen = GetSystemMetrics(SM_CYSCREEN) ;      SetTimer (hwnd, ID_TIMER, 10, NULL) ;      hdc = GetDC(hwnd);      hdcMem = CreateCompatibleDC(hdc);      hBitmap = CreateCompatibleBitmap(hdc, cxScreen, cyScreen);      SelectObject(hdcMem, hBitmap);      ReleaseDC(hwnd, hdc);      //创建字体      hFont = CreateFont(iFontHeight, iFontWidth-5, 0, 0, FW_BOLD, 0, 0, 0,                DEFAULT_CHARSET, OUT_DEFAULT_PRECIS, CLIP_DEFAULT_PRECIS,                DRAFT_QUALITY, FIXED_PITCH | FF_SWISS, TEXT("Fixedsys"));      SelectObject(hdcMem, hFont);      DeleteObject (hFont) ;      SetBkMode(hdcMem, TRANSPARENT); //设置背景模式为 透明      iColumnCount = cxScreen/(iFontWidth*3/2); //屏幕所显示字母雨的列数      ccChain = (pCharColumn)calloc(iColumnCount, sizeof(CharColumn));      for(i=0; i<iColumnCount; i++)      {        init(ccChain+i, cyScreen, (iFontWidth*3/2)*i);      }      return 0 ;    case WM_TIMER:      hdc = GetDC(hwnd);      PatBlt (hdcMem, 0, 0, cxScreen, cyScreen, BLACKNESS) ; //将内存设备映像刷成黑色      for(i=0; i<iColumnCount; i++)      {        ctn = (ccChain+i)->iStopTimes++ > (ccChain+i)->iMustStopTimes;        //        (ccChain+i)->point = (ccChain+i)->head; //point用于遍历整个显示列                //第一个字符显示为 白色        SetTextColor(hdcMem, RGB(255, 255, 255));        TextOut(hdcMem, (ccChain+i)->x, (ccChain+i)->y, &((ccChain+i)->point->ch), 1);        j = (ccChain+i)->y;         (ccChain+i)->point = (ccChain+i)->point->next;        //遍历整个显示列,将这个显示列里的字符从下往上显示        temp = 0 ; //temp绿色过度到黑色之用        while((ccChain+i)->point != (ccChain+i)->head && (ccChain+i)->point->ch)        {            SetTextColor(hdcMem, RGB(0, 255-(255*(temp++)/(ccChain+i)->iStrLen), 0));            TextOut(hdcMem, (ccChain+i)->x, j-=iFontHeight, &((ccChain+i)->point->ch), 1);            (ccChain+i)->point = (ccChain+i)->point->next;        }        if(ctn)          (ccChain+i)->iStopTimes = 0 ;        else continue;        (ccChain+i)->y += iFontHeight; //下次开始显示的y坐标 为当前的y坐标加上 一个字符的高度        //如果开始显示的y坐标减去 整个显示列的长度超过了屏幕的高度        if( (ccChain+i)->y-(ccChain+i)->iStrLen*iFontHeight > cyScreen)        {            free( (ccChain+i)->current );            init(ccChain+i, cyScreen, (iFontWidth*3/2)*i);        }        //链表的头 为此链表的前个元素,因为下次开始显示的时候 就相当与在整个显示列的开头添加个元素,然后在开始往上显示        (ccChain+i)->head = (ccChain+i)->head->prev;        (ccChain+i)->head->ch = randomChar();      }            BitBlt(hdc, 0, 0, cxScreen, cyScreen, hdcMem, 0, 0, SRCCOPY);      ReleaseDC(hwnd, hdc);      return 0;    case WM_RBUTTONDOWN:      KillTimer (hwnd, ID_TIMER) ;      return 0;    case WM_RBUTTONUP:      SetTimer (hwnd, ID_TIMER, 10, NULL) ;      return 0;    //处理善后工作    case WM_KEYDOWN:    case WM_LBUTTONDOWN:    case WM_DESTROY:      KillTimer (hwnd, ID_TIMER) ;      DeleteObject(hBitmap);      DeleteDC(hdcMem);      for(i=0; i<iColumnCount; i++)      {        free( (ccChain+i)->current );      }      free(ccChain);      PostQuitMessage (0) ;      return 0 ;    }    return DefWindowProc (hwnd, message, wParam, lParam) ;}