ddmm.cpp

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//------------------------------------------------------------------------------
// File: DDMM.cpp
//
// Desc: DirectShow base classes - implements routines for using DirectDraw
//       on a multimonitor system.
//
// Copyright (c) 1995-2001 Microsoft Corporation.  All rights reserved.
//------------------------------------------------------------------------------


#include <streams.h>
#include <ddraw.h>
#include "ddmm.h"

/*
 * FindDeviceCallback
 */
typedef struct {
    LPSTR   szDevice;
    GUID*   lpGUID;
    GUID    GUID;
    BOOL    fFound;
}   FindDeviceData;

BOOL CALLBACK FindDeviceCallback(__in_opt GUID* lpGUID, __in LPSTR szName, __in LPSTR szDevice, __in LPVOID lParam)
{
    FindDeviceData *p = (FindDeviceData*)lParam;

    if (lstrcmpiA(p->szDevice, szDevice) == 0) {
        if (lpGUID) {
        p->GUID = *lpGUID;
        p->lpGUID = &p->GUID;
        } else {
        p->lpGUID = NULL;
        }
        p->fFound = TRUE;
        return FALSE;
    }
    return TRUE;
}


BOOL CALLBACK FindDeviceCallbackEx(__in_opt GUID* lpGUID, __in LPSTR szName, __in LPSTR szDevice, __in LPVOID lParam, HMONITOR hMonitor)
{
    FindDeviceData *p = (FindDeviceData*)lParam;

    if (lstrcmpiA(p->szDevice, szDevice) == 0) {
        if (lpGUID) {
        p->GUID = *lpGUID;
        p->lpGUID = &p->GUID;
        } else {
        p->lpGUID = NULL;
        }
        p->fFound = TRUE;
        return FALSE;
    }
    return TRUE;
}


/*
 * DirectDrawCreateFromDevice
 *
 * create a DirectDraw object for a particular device
 */
IDirectDraw * DirectDrawCreateFromDevice(__in_opt LPSTR szDevice, PDRAWCREATE DirectDrawCreateP, PDRAWENUM DirectDrawEnumerateP)
{
    IDirectDraw*    pdd = NULL;
    FindDeviceData  find;

    if (szDevice == NULL) {
        DirectDrawCreateP(NULL, &pdd, NULL);
        return pdd;
    }

    find.szDevice = szDevice;
    find.fFound   = FALSE;
    DirectDrawEnumerateP(FindDeviceCallback, (LPVOID)&find);

    if (find.fFound)
    {
        //
        // In 4bpp mode the following DDraw call causes a message box to be popped
        // up by DDraw (!?!).  It's DDraw's fault, but we don't like it.  So we
        // make sure it doesn't happen.
        //
        UINT ErrorMode = SetErrorMode(SEM_FAILCRITICALERRORS);
        DirectDrawCreateP(find.lpGUID, &pdd, NULL);
        SetErrorMode(ErrorMode);
    }

    return pdd;
}


/*
 * DirectDrawCreateFromDeviceEx
 *
 * create a DirectDraw object for a particular device
 */
IDirectDraw * DirectDrawCreateFromDeviceEx(__in_opt LPSTR szDevice, PDRAWCREATE DirectDrawCreateP, LPDIRECTDRAWENUMERATEEXA DirectDrawEnumerateExP)
{
    IDirectDraw*    pdd = NULL;
    FindDeviceData  find;

    if (szDevice == NULL) {
        DirectDrawCreateP(NULL, &pdd, NULL);
        return pdd;
    }

    find.szDevice = szDevice;
    find.fFound   = FALSE;
    DirectDrawEnumerateExP(FindDeviceCallbackEx, (LPVOID)&find,
                    DDENUM_ATTACHEDSECONDARYDEVICES);

    if (find.fFound)
    {
        //
        // In 4bpp mode the following DDraw call causes a message box to be popped
        // up by DDraw (!?!).  It's DDraw's fault, but we don't like it.  So we
        // make sure it doesn't happen.
        //
        UINT ErrorMode = SetErrorMode(SEM_FAILCRITICALERRORS);
        DirectDrawCreateP(find.lpGUID, &pdd, NULL);
        SetErrorMode(ErrorMode);
    }

    return pdd;
}