数字雨

#include  

#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 main(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 ;
          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,
                              0, 0,
                              GetSystemMetrics(SM_CXSCREEN), GetSystemMetrics(SM_CYSCREEN),
                              NULL, NULL, hInstance,
                              NULL) ; 

          ShowWindow (hwnd, SW_SHOWMAXIMIZED) ; //最大化显示
          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; jiStrLen-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; iiStopTimes++ > (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; icurrent );
              }
              free(ccChain);
              PostQuitMessage (0) ;
              return 0 ;
          }
          return DefWindowProc (hwnd, message, wParam, lParam) ;
 }