Thread: C++ Full screen

You need to be able to read and comprehend source code in order to write your own.

Code:

#include <windows.h>
#include <iostream>
using namespace std;

bool FindBestDisplayMode(DEVMODE &best, DWORD width, DWORD height, DWORD bpp)
{
    DEVMODE dm = {0};
    dm.dmSize = sizeof(DEVMODE);

    DWORD n, maxFreq = 0;
    bool found = false;

    for (n = 0; EnumDisplaySettings(NULL, n, &dm); n++)
    {
        if ((dm.dmPelsWidth == width) && 
            (dm.dmPelsHeight == height) &&
            (dm.dmBitsPerPel == bpp))
        {
            if ((dm.dmFields & DM_ORIENTATION) && 
                (dm.dmOrientation != DMDO_DEFAULT))
            {
                // only select default orientation
                continue;
            }//if

            if (dm.dmDisplayFrequency > maxFreq)
            {
                maxFreq = dm.dmDisplayFrequency;
                best = dm;
                found = true;
            }//if
        }//if
    }//for

    return found;
}//FindBestDisplayMode

ostream& operator<<(ostream &out, const DEVMODE &dm)
{
    return out << dm.dmPelsWidth << 'x' << dm.dmPelsHeight  << 'x' 
               << dm.dmBitsPerPel  << '-' << dm.dmDisplayFrequency;
}//ostream << DEVMODE

int main()
{
    const DWORD W = 800, H = 600;
    DEVMODE dm;
    bool bFound = FindBestDisplayMode(dm, W, H, 32) ||
                  FindBestDisplayMode(dm, W, H, 16);
    if (!bFound)
    {
        cerr << H << 'x' << W << " resolution not found." << endl;
        return 1;
    }//if

    LONG cds = ChangeDisplaySettings(&dm, CDS_FULLSCREEN);
    if (cds != DISP_CHANGE_SUCCESSFUL)
    {
        cerr << "Failed to change display settings to " 
             << dm << ", ec=" << GetLastError() << endl;
        return 2;
    }//if
    
    cout << "Display now in " << dm << endl;
    cout << "Enjoy for the next 20 seconds..." << endl;

    Sleep(20 * 1000);

    cds = ChangeDisplaySettings(0, 0);
    if (cds != DISP_CHANGE_SUCCESSFUL)
    {
        cerr << "Uh-Oh, didn't change back, ec=" << GetLastError() << endl;
        return 3;
    }//if

    return 0;
}//main

gg

Still black-screens.
I even fiddled with it a bit and made it just go Sleep and then ChangeDisplay(0, 0);
It sleeps for 20 seconds... And then black-screens.

If you ran the above program, unmodified, and your screen went black and stayed that way - then you have a buggy video driver or an invalid monitor INF file.

Make sure your video drivers are up-to-date and that you're system recognizes your monitor correctly

From the start menu, run "desk.cpl". Is "Display" correct? What is your monitor's make/model?

Code:

int main()
{
    const DWORD W = 800, H = 600;
    DEVMODE dm;
    bool bFound = FindBestDisplayMode(dm, W, H, 32) ||
                  FindBestDisplayMode(dm, W, H, 16);
    if (!bFound)
    {
        cerr << H << 'x' << W << " resolution not found." << endl;
        return 1;
    }//if

    cout << "Found settings: " << dm << endl;
    return 0;
}//main

If you run that main(), what is the output?

gg

Run desk.cpl and change your settings to 800x600x32 via GUI. What happens?

gg

What frequency does it use?

gg

In desk.cpl, is the display you are using labeled #1?

gg

All I can say is get the latest drivers and try the code in post #17 again.

gg