moving in tunnel

boring sunday & i had couple of hours free from kid .so i came up with this very dumb and raw program of using arrow keys"up and down arrows only" to move a ball in this if i can call it 3d tunnel .i got called upon and couldnt finish it.so if any one can give advice on fixing its many shortcomings u welcome.

there are few problems like;

white flickers as u move the ball ahead or back.


by the way if this should be in game programming section

please feel free to move it.

Code:

---

*------------------------------------------------------------
 
                Sia k
  ------------------------------------------------------------*/

#include <windows.h>

#include <stdio.h>
#define ID_TIMER 1

LRESULT CALLBACK WndProc (HWND, UINT, WPARAM, LPARAM) ;

int WINAPI WinMain (HINSTANCE hInstance, HINSTANCE hPrevInstance,
                    PSTR szCmdLine, int iCmdShow)
{
    static char szAppName[] = TEXT ("Hello Lovely Sara") ;
       
    HWND        hwnd ;
    MSG          msg ;
    WNDCLASSEX    wndclass ;
    wndclass.cbSize        = sizeof(wndclass);
    wndclass.style        = CS_HREDRAW | CS_VREDRAW | CS_OWNDC ;
    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(WHITE_BRUSH);
    wndclass.lpszMenuName  = NULL ;
    wndclass.lpszClassName = szAppName ;
    wndclass.hIconSm      = LoadIcon(NULL, IDI_APPLICATION);

    RegisterClassEx(&wndclass);
   
     
                   
     
   
   
    hwnd = CreateWindow (szAppName,                  // window class name
                          TEXT ("The, Hello Lovely Sara"), // window caption
                          WS_OVERLAPPEDWINDOW,        // window style
                          CW_USEDEFAULT,              // initial x position
                          CW_USEDEFAULT,              // initial y position
                          CW_USEDEFAULT,              // initial x size
                          CW_USEDEFAULT,              // initial y size
                          NULL,                      // parent window handle
                          NULL,                      // window menu handle
                          hInstance,                  // program instance handle
                          NULL) ;                    // creation parameters
   
    ShowWindow (hwnd, iCmdShow) ;
    UpdateWindow (hwnd) ;
   
    while (GetMessage (&msg, NULL, 0, 0))
    {
          TranslateMessage (&msg) ;
          DispatchMessage (&msg) ;
    }
    return msg.wParam ;
}

LRESULT CALLBACK WndProc (HWND hwnd, UINT message, WPARAM wParam, LPARAM lParam)
{
            BOOL b = TRUE;
   
static  HDC  hdc;
        PAINTSTRUCT ps ;
static  HBRUSH hbrush;

       
static int cxchar, cychar, cxclient, cyclient, i, j = 0, p = 0, n = 255, m = 25, f = 50, d = 50, s = 130,
                cxs, cys;
            //HINSTANCE hInstance;
            TEXTMETRIC tm;
static        RECT rect;
static  HRGN ergn;                //not utilized yet
       
       
       
       
       
 
    switch (message)
    {
    case WM_CREATE:
        // SetTimer(hwnd, ID_TIMER, 500, NULL);            //not utilized yet
       
       

               
             
           

               
                  hdc = GetDC(hwnd);
               
                  GetTextMetrics(hdc, &tm);
         
                  cxchar = tm.tmAveCharWidth;
                  cychar = tm.tmHeight + tm.tmExternalLeading;
          ReleaseDC(hwnd, hdc);
               
               
       
                  return 0;
      case WM_SIZE:
                         
                  cxclient = LOWORD(lParam);
                       
          cyclient = HIWORD(lParam);
                       
                return 0;
        case WM_PAINT:
                  hdc =  BeginPaint (hwnd, &ps) ;
               
   
       
       
       
         
                for(i = 0; i < 130 ; i++){
          rect.left  =            i * cxclient / 255 ;
          rect.top    =            i * cyclient / 255 ;
          rect.right  = cxclient - i * cxclient / 255 ;
          rect.bottom = cyclient - i * cyclient / 255 ;

         


          hbrush = CreateSolidBrush(RGB(255 - p, 255 - p, 255 - p));
        p += 2;
       
              FillRect(hdc, &rect, hbrush);
                }
       
                hbrush = CreateSolidBrush(RGB(245, 245, 245));
        SelectObject(hdc, hbrush);

        Rectangle(hdc,s * cxclient / 255  ,s * cyclient / 255,
        cxclient - s * cxclient / 255, cyclient - s * cyclient / 255);
                   
         

     

        DeleteObject(hbrush);
        hbrush = CreateSolidBrush(RGB(255, 0, 0));
        SelectObject(hdc, hbrush);

        Ellipse(hdc, (cxclient / 2)- 5 ,cyclient - m, cxclient / 2 + f, (cyclient - m) + d);
            DeleteObject(hbrush);
        // }
            p = 0;
            EndPaint (hwnd, &ps) ;
            return 0 ; 
       
    // case WM_TIMER:
               
                // b = !b;                        //not utilized yet
                // return 0;
    case WM_KEYDOWN:
                switch(wParam){
                case VK_UP:
    if(m < (cyclient / 2)  && f > 0 && d > 0){
            m += 15;
                f -=2;
                d -=2;
         
                }
                s--;
                break;
                case VK_DOWN:
      if(m < (cyclient / 2) && m >= 25 && f > 0 && d > 0){
            m -= 15;
                f +=2;
                d +=2;
         
                }
                s++;
                break;
                }
                InvalidateRect(hwnd, NULL, TRUE);
          return 0;
    case WM_DESTROY:
               
                  //KillTimer(hwnd, ID_TIMER);
       
       
                  DeleteObject(hbrush);
          PostQuitMessage (0) ;
          return 0 ;
    }
    return DefWindowProc (hwnd, message, wParam, lParam) ;
}

---

Try some double buffering.

You are doing all the drawing in the paint function.
Try having two HDC's (CreateCompatibleDC() ) create at start and kill at end of program,

On the move or timer do the drawing to one. When finished the drawing copy this HDC to the second.
Call for a paint (InvalidateRect() ect)

In the paint msg just copy the second HDC to the one from begin paint.

This will mean keep the old image on screen while the new one is assembled reducing filcker.

(Use GetUpdateRect() BEFORE the call to begin paint to find if only a small area needs painting)

THX novacain . as u noticed this was a very crude & no proof checking program without much thought put into it .

but since my last post i came up with the solution very similar to yours and it works fine and added logic for left and right arrow.
,plus a bitmap "road extension" at the end of the tunnel.and opened a second tunnel off the side of this one,(move away quake here we come) hehe! but your GetUpdateRect() helped quite a bit.

by the way how many of you get your best ideas or code solutions when you hit the bed "when u r actually suppose to sleep"?:

I 'found' a memory error that had been crashing my app (and I had been looking for for two days) while I was driving down the road. One second there are cars all around me, next second they are miles in front and I have the solution.

Lucky my car knows the way home......