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//-----------------------------------------------------------------------------// File: DDEx1.CPP//// Desc: Direct Draw example program 1.  Creates a Direct Draw//       object and then a primary surface with a back buffer.//       Slowly flips between the primary surface and the back//       buffer.  Press F12 to terminate the program.//// Copyright (c) 1995-1999 Microsoft Corporation. All rights reserved.//-----------------------------------------------------------------------------#ifndef WIN32_LEAN_AND_MEAN#define WIN32_LEAN_AND_MEAN#endif//-----------------------------------------------------------------------------// Include files//-----------------------------------------------------------------------------#include <windows.h>#include <ddraw.h>#include <stdio.h>#include <stdarg.h>#include "resource.h"//-----------------------------------------------------------------------------// Local definitions//-----------------------------------------------------------------------------#define NAME                "DDExample1"#define TITLE               "Direct Draw Example 1"//-----------------------------------------------------------------------------// Default settings//-----------------------------------------------------------------------------#define TIMER_ID            1#define TIMER_RATE          500//-----------------------------------------------------------------------------// Global data//-----------------------------------------------------------------------------LPDIRECTDRAW7               g_pDD = NULL;        // DirectDraw objectLPDIRECTDRAWSURFACE7        g_pDDSPrimary = NULL;// DirectDraw primary surfaceLPDIRECTDRAWSURFACE7        g_pDDSBack = NULL;   // DirectDraw back surfaceBOOL                        g_bActive = FALSE;   // Is application active?//-----------------------------------------------------------------------------// Local data//-----------------------------------------------------------------------------static char                 szMsg[] = "Page Flipping Test: Press F12 to exit";static char                 szFrontMsg[] = "Front buffer (F12 to quit)";static char                 szBackMsg[] = "Back buffer (F12 to quit)";//-----------------------------------------------------------------------------// Name: ReleaseAllObjects()// Desc: Finished with all objects we use; release them//-----------------------------------------------------------------------------static voidReleaseAllObjects(void){    if (g_pDD != NULL)    {        if (g_pDDSPrimary != NULL)        {            g_pDDSPrimary->Release();            g_pDDSPrimary = NULL;        }        g_pDD->Release();        g_pDD = NULL;    }}//-----------------------------------------------------------------------------// Name: InitFail()// Desc: This function is called if an initialization function fails//-----------------------------------------------------------------------------HRESULTInitFail(HWND hWnd, HRESULT hRet, LPCTSTR szError,...){    char                        szBuff[128];    va_list                     vl;    va_start(vl, szError);    vsprintf(szBuff, szError, vl);    ReleaseAllObjects();    MessageBox(hWnd, szBuff, TITLE, MB_OK);    DestroyWindow(hWnd);    va_end(vl);    return hRet;}//-----------------------------------------------------------------------------// Name: UpdateFrame()// Desc: Displays the proper text for the page//-----------------------------------------------------------------------------static voidUpdateFrame(HWND hWnd){    static BYTE                 phase = 0;    HDC                         hdc;    DDBLTFX                     ddbltfx;    RECT                        rc;    SIZE                        size;    // Use the blter to do a color fill to clear the back buffer    ZeroMemory(&ddbltfx, sizeof(ddbltfx));    ddbltfx.dwSize = sizeof(ddbltfx);    ddbltfx.dwFillColor = 0;    g_pDDSBack->Blt(NULL, NULL, NULL, DDBLT_COLORFILL | DDBLT_WAIT, &ddbltfx);    if (g_pDDSBack->GetDC(&hdc) == DD_OK)    {        SetBkColor(hdc, RGB(0, 0, 255));        SetTextColor(hdc, RGB(255, 255, 0));        if (phase)        {            GetClientRect(hWnd, &rc);            GetTextExtentPoint(hdc, szMsg, lstrlen(szMsg), &size);            TextOut(hdc, (rc.right - size.cx) / 2, (rc.bottom - size.cy) / 2,                    szMsg, sizeof(szMsg) - 1);            TextOut(hdc, 0, 0, szFrontMsg, lstrlen(szFrontMsg));            phase = 0;        }        else        {            TextOut(hdc, 0, 0, szBackMsg, lstrlen(szBackMsg));            phase = 1;        }        g_pDDSBack->ReleaseDC(hdc);    }}//-----------------------------------------------------------------------------// Name: WindowProc()// Desc: The Main Window Procedure//-----------------------------------------------------------------------------long FAR PASCALWindowProc(HWND hWnd, UINT message, WPARAM wParam, LPARAM lParam){    HRESULT                     hRet;    switch (message)    {        case WM_ACTIVATE:            // Pause if minimized            g_bActive = !((BOOL)HIWORD(wParam));            return 0L;        case WM_DESTROY:            // Clean up and close the app            ReleaseAllObjects();            PostQuitMessage(0);            return 0L;        case WM_KEYDOWN:            // Handle any non-accelerated key commands            switch (wParam)            {                case VK_ESCAPE:                case VK_F12:                    PostMessage(hWnd, WM_CLOSE, 0, 0);                    return 0L;            }            break;        case WM_SETCURSOR:            // Turn off the cursor since this is a full-screen app            SetCursor(NULL);            return TRUE;        case WM_TIMER:            // Update and flip surfaces            if (g_bActive && TIMER_ID == wParam)            {                UpdateFrame(hWnd);                while (TRUE)                {                    hRet = g_pDDSPrimary->Flip(NULL, 0);                    if (hRet == DD_OK)                        break;                    if (hRet == DDERR_SURFACELOST)                    {                        hRet = g_pDDSPrimary->Restore();                        if (hRet != DD_OK)                            break;                    }                    if (hRet != DDERR_WASSTILLDRAWING)                        break;                }            }            break;    }    return DefWindowProc(hWnd, message, wParam, lParam);}//-----------------------------------------------------------------------------// Name: InitApp()// Desc: Do work required for every instance of the application://          Create the window, initialize data//-----------------------------------------------------------------------------static HRESULTInitApp(HINSTANCE hInstance, int nCmdShow){    HWND                        hWnd;    WNDCLASS                    wc;    DDSURFACEDESC2              ddsd;    DDSCAPS2                    ddscaps;    HRESULT                     hRet;    // Set up and register window class    wc.style = CS_HREDRAW | CS_VREDRAW;    wc.lpfnWndProc = WindowProc;    wc.cbClsExtra = 0;    wc.cbWndExtra = 0;    wc.hInstance = hInstance;    wc.hIcon = LoadIcon(hInstance, MAKEINTRESOURCE(IDI_MAIN_ICON));    wc.hCursor = LoadCursor(NULL, IDC_ARROW);    wc.hbrBackground = (HBRUSH )GetStockObject(BLACK_BRUSH);    wc.lpszMenuName = NAME;    wc.lpszClassName = NAME;    RegisterClass(&wc);    // Create a window    hWnd = CreateWindowEx(WS_EX_TOPMOST,                          NAME,                          TITLE,                          WS_POPUP,                          0,                          0,                          GetSystemMetrics(SM_CXSCREEN),                          GetSystemMetrics(SM_CYSCREEN),                          NULL,                          NULL,                          hInstance,                          NULL);    if (!hWnd)        return FALSE;    ShowWindow(hWnd, nCmdShow);    UpdateWindow(hWnd);    SetFocus(hWnd);    ///////////////////////////////////////////////////////////////////////////    // Create the main DirectDraw object    ///////////////////////////////////////////////////////////////////////////    hRet = DirectDrawCreateEx(NULL, (VOID**)&g_pDD, IID_IDirectDraw7, NULL);    if (hRet != DD_OK)        return InitFail(hWnd, hRet, "DirectDrawCreateEx FAILED");    // Get exclusive mode    hRet = g_pDD->SetCooperativeLevel(hWnd, DDSCL_EXCLUSIVE | DDSCL_FULLSCREEN);    if (hRet != DD_OK)        return InitFail(hWnd, hRet, "SetCooperativeLevel FAILED");    // Set the video mode to 640x480x8    hRet = g_pDD->SetDisplayMode(640, 480, 8, 0, 0);    if (hRet != DD_OK)        return InitFail(hWnd, hRet, "SetDisplayMode FAILED");    // Create the primary surface with 1 back buffer    ZeroMemory(&ddsd, sizeof(ddsd));    ddsd.dwSize = sizeof(ddsd);    ddsd.dwFlags = DDSD_CAPS | DDSD_BACKBUFFERCOUNT;    ddsd.ddsCaps.dwCaps = DDSCAPS_PRIMARYSURFACE | DDSCAPS_FLIP |                          DDSCAPS_COMPLEX;    ddsd.dwBackBufferCount = 1;    hRet = g_pDD->CreateSurface(&ddsd, &g_pDDSPrimary, NULL);    if (hRet != DD_OK)        return InitFail(hWnd, hRet, "CreateSurface FAILED");    // Get a pointer to the back buffer    ZeroMemory(&ddscaps, sizeof(ddscaps));    ddscaps.dwCaps = DDSCAPS_BACKBUFFER;    hRet = g_pDDSPrimary->GetAttachedSurface(&ddscaps, &g_pDDSBack);    if (hRet != DD_OK)        return InitFail(hWnd, hRet, "GetAttachedSurface FAILED");    // Create a timer to flip the pages    if (TIMER_ID != SetTimer(hWnd, TIMER_ID, TIMER_RATE, NULL))        return InitFail(hWnd, hRet, "SetTimer FAILED");    return DD_OK;}//-----------------------------------------------------------------------------// Name: WinMain()// Desc: Initialization, message loop//-----------------------------------------------------------------------------int PASCALWinMain(HINSTANCE hInstance,        HINSTANCE hPrevInstance,        LPSTR lpCmdLine,        int nCmdShow){    MSG                         msg;    if (InitApp(hInstance, nCmdShow) != DD_OK)        return FALSE;    while (GetMessage(&msg, NULL, 0, 0))    {        TranslateMessage(&msg);        DispatchMessage(&msg);    }    return msg.wParam;}

//{{NO_DEPENDENCIES}}// Microsoft Developer Studio generated include file.// Used by Script1.rc//#define IDI_ICON1                       101// Next default values for new objects// #ifdef APSTUDIO_INVOKED#ifndef APSTUDIO_READONLY_SYMBOLS#define _APS_NEXT_RESOURCE_VALUE        102#define _APS_NEXT_COMMAND_VALUE         40001#define _APS_NEXT_CONTROL_VALUE         1000#define _APS_NEXT_SYMED_VALUE           101#endif#endif