GHOST_DisplayManagerWin32.cpp

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/*
 * ***** BEGIN GPL LICENSE BLOCK *****
 *
 * This program is free software; you can redistribute it and/or
 * modify it under the terms of the GNU General Public License
 * as published by the Free Software Foundation; either version 2
 * of the License, or (at your option) any later version.
 *
 * This program is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License
 * along with this program; if not, write to the Free Software Foundation,
 * Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
 *
 * The Original Code is Copyright (C) 2001-2002 by NaN Holding BV.
 * All rights reserved.
 *
 * The Original Code is: all of this file.
 *
 * Contributor(s): none yet.
 *
 * ***** END GPL LICENSE BLOCK *****
 */

#include "GHOST_DisplayManagerWin32.h"
#include "GHOST_Debug.h"

#define _WIN32_WINNT 0x501 // require Windows XP or newer
#define WIN32_LEAN_AND_MEAN
#include <windows.h>

// We do not support multiple monitors at the moment
#define COMPILE_MULTIMON_STUBS
#ifndef FREE_WINDOWS
#include <multimon.h>
#endif


GHOST_DisplayManagerWin32::GHOST_DisplayManagerWin32(void)
{
}


GHOST_TSuccess GHOST_DisplayManagerWin32::getNumDisplays(GHOST_TUns8& numDisplays) const
{
    // We do not support multiple monitors at the moment
    numDisplays = ::GetSystemMetrics(SM_CMONITORS);
    return numDisplays > 0 ? GHOST_kSuccess : GHOST_kFailure;
}


/*
 * When you call EnumDisplaySettings with iModeNum set to zero, the operating system 
 * initializes and caches information about the display device. When you call 
 * EnumDisplaySettings with iModeNum set to a non-zero value, the function returns 
 * the information that was cached the last time the function was called with iModeNum
 * set to zero. 
 */
GHOST_TSuccess GHOST_DisplayManagerWin32::getNumDisplaySettings(GHOST_TUns8 display, GHOST_TInt32& numSettings) const
{
    GHOST_ASSERT((display==kMainDisplay), "GHOST_DisplayManagerWin32::getNumDisplaySettings(): only main displlay is supported");
    numSettings = 0;
    DEVMODE dm;
    while (::EnumDisplaySettings(NULL, numSettings, &dm)) {
        numSettings++;
    }
    return GHOST_kSuccess;
}


GHOST_TSuccess GHOST_DisplayManagerWin32::getDisplaySetting(GHOST_TUns8 display, GHOST_TInt32 index, GHOST_DisplaySetting& setting) const
{
    GHOST_ASSERT((display==kMainDisplay), "GHOST_DisplayManagerWin32::getDisplaySetting(): only main display is supported");
    GHOST_TSuccess success;
    DEVMODE dm;
    if (::EnumDisplaySettings(NULL, index, &dm)) {
#ifdef GHOST_DEBUG
        printf("display mode: width=%d, height=%d, bpp=%d, frequency=%d\n", dm.dmPelsWidth, dm.dmPelsHeight, dm.dmBitsPerPel, dm.dmDisplayFrequency);
#endif // GHOST_DEBUG
        setting.xPixels     = dm.dmPelsWidth;
        setting.yPixels     = dm.dmPelsHeight;
        setting.bpp         = dm.dmBitsPerPel;
        /* When you call the EnumDisplaySettings function, the dmDisplayFrequency member
         * may return with the value 0 or 1. These values represent the display hardware's
         * default refresh rate. This default rate is typically set by switches on a display 
         * card or computer motherboard, or by a configuration program that does not use 
         * Win32 display functions such as ChangeDisplaySettings. 
         */
        /* First, we tried to explicitly set the frequency to 60 if EnumDisplaySettings
         * returned 0 or 1 but this doesn't work since later on an exact match will
         * be searched. And this will never happen if we change it to 60. Now we rely
         * on the default h/w setting.
         */
        setting.frequency = dm.dmDisplayFrequency;
        success = GHOST_kSuccess;
    }
    else {
        success = GHOST_kFailure;
    }
    return success;
}


GHOST_TSuccess GHOST_DisplayManagerWin32::getCurrentDisplaySetting(GHOST_TUns8 display, GHOST_DisplaySetting& setting) const
{
    GHOST_ASSERT((display==kMainDisplay), "GHOST_DisplayManagerWin32::getCurrentDisplaySetting(): only main display is supported");
    return getDisplaySetting(kMainDisplay, ENUM_CURRENT_SETTINGS, setting);
}


GHOST_TSuccess GHOST_DisplayManagerWin32::setCurrentDisplaySetting(GHOST_TUns8 display, const GHOST_DisplaySetting& setting)
{
    GHOST_ASSERT((display==kMainDisplay), "GHOST_DisplayManagerWin32::setCurrentDisplaySetting(): only main display is supported");

    GHOST_DisplaySetting match;
    findMatch(display, setting, match);
    DEVMODE dm;
    int i = 0;
    while (::EnumDisplaySettings(NULL, i++, &dm)) {
        if ((dm.dmBitsPerPel == match.bpp) &&
            (dm.dmPelsWidth == match.xPixels) &&
            (dm.dmPelsHeight == match.yPixels) &&
            (dm.dmDisplayFrequency == match.frequency)) {
            break;
        }
    }
    /*
    dm.dmBitsPerPel = match.bpp;
    dm.dmPelsWidth = match.xPixels;
    dm.dmPelsHeight = match.yPixels;
    dm.dmDisplayFrequency = match.frequency;
    dm.dmFields = DM_BITSPERPEL | DM_PELSWIDTH | DM_PELSHEIGHT | DM_DISPLAYFREQUENCY;
    dm.dmSize = sizeof(DEVMODE);
    dm.dmDriverExtra = 0;
    */
#ifdef GHOST_DEBUG
    printf("display change: Requested settings:\n");
    printf("  dmBitsPerPel=%d\n", dm.dmBitsPerPel);
    printf("  dmPelsWidth=%d\n", dm.dmPelsWidth);
    printf("  dmPelsHeight=%d\n", dm.dmPelsHeight);
    printf("  dmDisplayFrequency=%d\n", dm.dmDisplayFrequency);
#endif // GHOST_DEBUG

    LONG status = ::ChangeDisplaySettings(&dm, CDS_FULLSCREEN);
#ifdef GHOST_DEBUG
    switch (status)
    {
    case DISP_CHANGE_SUCCESSFUL:
        printf("display change: The settings change was successful.\n");
        break;
    case DISP_CHANGE_RESTART:
        printf("display change: The computer must be restarted in order for the graphics mode to work.\n");
        break;
    case DISP_CHANGE_BADFLAGS:
        printf("display change: An invalid set of flags was passed in.\n");
        break;
    case DISP_CHANGE_BADPARAM:
        printf("display change: An invalid parameter was passed in. This can include an invalid flag or combination of flags.\n");
        break;
    case DISP_CHANGE_FAILED:
        printf("display change: The display driver failed the specified graphics mode.\n");
        break;
    case DISP_CHANGE_BADMODE:
        printf("display change: The graphics mode is not supported.\n");
        break;
    case DISP_CHANGE_NOTUPDATED:
        printf("display change: Windows NT: Unable to write settings to the registry.\n");
        break;
    default:
        printf("display change: Return value invalid\n");
        break;
    }
#endif // GHOST_DEBUG
    return status == DISP_CHANGE_SUCCESSFUL? GHOST_kSuccess : GHOST_kFailure;
}