_IMPLEMENTING GAMES FOR WINDOWS_
by James Finnegan

Example 1:

(a)

xor ax,ax
mov ah,80h
add ax, ax ;;Will o/flow in 16 bits
jc  short &n&_fix_cs


(b)

mov bx,cs
 ...
mov es,ax
mov di.sp
mov ax,000Bh
int 31h ;;; DPMI: Get the CS descr
;;; change the following to USE32
or  byte ptr es:[di+6],40h
mov ax,000Ch
int 31h ;;; DPMI.  Set the CS descr


(c)

xor eax,eax
mov ah,80h
add eax,eax ;; Doesn't overflow in 32 bits
jc  short &n&_fix_cs



Example 2:

(a)

WinGRecommendDIB Format((BITMAPINFO far*)&WinGDIBHeader.bmiHeader);


(b)

for(iColorIndex = 10;iColorIndex < 246;iColorIndex++)
{
WinGDIBHeader.bmiColors[iColorIndex].rgbRed                 =
                 LogicalPalette.palEntries[iColorIndex].peRed   =
                 pColorTable[icolorIndex].rgbRed;
        WinGDIBHeader.bmiColors[iColorIndexl.rgbGreen           =
                 LogicalPalette.palEntries[iColorIndex].peGreen =
                 pColorTable[iColorIndex].rgbGreen;
        WinGDIBHeader.bmiColors[iColorIndex].rgbBlue            =
                 LogicalPdlette.palEntries[iColorIndex].peBlue  =
                 pColorTable[icolorIndexl.rgbBlue:
        WinGDIBHeader.bmiColors[!ColorIndexj.rgbReserved        = 0;
                 // This flag includes PC_NOCOLLAPSE
        LogicalPalette.palEntries[iColorlndexl.peFlags          =
                 PC_RESERVED;
        }


(c)

// Get the 20 static colors
hDC = GetDC(O);
GetSystemPaletteEntries(hDC,0,10,LogicalPalette.palEntries);
GetSystemPaletteEntries(hDC,246,10,LogicalPalette.palEntries + 246):
ReleaseDC(0,hDC);


(d)

ghMSJIdentityPalette = CreatePalette((LOGPALETTE far*) &LogicalPalette):


(e)

SelectPalette(hDC,ghMSJldentityPalette,FALSE); 
RealizePalette(hDC);



Example 3:

(a)

ghWinGBackgroundDC = WinGCreateDC():


(b)

hBitmap = WinGCreateBitmap(ghWinGBackgroundDC,
                          (BITMAPINFO far*)&WinGBackgroundDIBHeader,
                          (void far*)&ghpWinGBackgroundBitmap);


(c)

gbm0ldBackgroundBitmap=(HBITMAP)SelectObject(ghWinGBackgroundDC,hBitmap);


(d)
StretchDIBits(ghWinGBackgroundDC,0,0,giWindowX,giWindowY,0,0,
  DibWidth(gpdibBackgroundBitmap),DibHeight(gpdibBackgroundBitmap),
  DibPtr(gpdibBackgroundBitmap),DibInfo(gpdibBackgroundBitmap),
  DIB_RGB_COLORS,SRCCOPY);


(e)

ghWinGDC = WinGCreateDC();
hBitmap = WinGCreateBitmap(ghWinGDC,(BITMAPINFO far*)&WinGDIBHeader, (void far *)&ghpWinGBitmap):
gbm0ldBitmap = (HBITMAP)SelectObject(ghWinGDC,hbitmap);


(f)

BitBlt(ghWinGDC,0,0,0,giWindowX,giWindowY,ghWinGBackgroundDC,0,0,SRCCOPY);



(g)

hDC = BeginPaint(hWnd,&ps);
SelectPalette(hDC,ghMSJldentityPalette,FALSE);
RealizePalette(hDC);
WinGBitBlt(hDC,0,0,giWindowX,giWindowY,ghWinGDC,0,0);
EndPaint(hWnd,&ps);



Example 4:

(a)

 mcConfig.wSize         = sizeof(MIXCONFIG);
 mcConfig.dwFlags   = WMIX_CONFIG_CHANNELS;
 mcConfig.wChannels = 2:
                    // Start up Wavemix
 ghMixSession           = WaveMixConfigureInit(&mcConfig);


(b)

glpMixl=WaveMixOpenWave(ghMixSession,"1.wav",NULL,WMIX_FILE);
glpMix2=WaveMixOpenWave(ghMixSession,"2.wav",NULL,WMIX_FILE);
glpMix3=WaveMixOpenWave(ghMixSession,"3.wav",NULL.WMIX_FILE);
glpMix4=WaveMixOpenWave(ghMixSession,"4.wav",NULL,WMIX_FILE);


(c)

WaveMixOpenChannel(ghMixSession,4,WHIX_OPENCOUNT):


(d)

case WM_ACTIVATE:
      // WA_INACTIVE == FALSE;
     WaveMixActivate(ghMixSession, wparam);
     break;


(e)
MixPlayParams.wSize = sizeof(MIXPLAYPARAMS);
MixPlayParams.hMixSession = ghMixSession;
MixPlayParams.hWndNotify = NULL:
MixP]ayParams.dwFlags=WMIX_HIPRIORITY;
MixPlayParams.wLoops=0;
MixPlayParams.iChannel=3;
MixPlayParams.lpMixWave=glpMix4;
WaveMixPlay(&MixPlayParams);