#DEFINE MONITOR_DEFAULTTONEAREST 2
DO declare
 
LOCAL hMonitor, cMonitorName, hPhysMonitor,;
    nPhysMonitorCount, cPhysMonitorArray, nResult
 
* find out on which monitor
* the main VFP window resides
hMonitor = MonitorFromWindow(_vfp.hWnd,;
    MONITOR_DEFAULTTONEAREST)
 
* find out the number of physical monitors
* associated with the hMonitor handle
nPhysMonitorCount=0
= GetNumberOfPhysicalMonitorsFromHMONITOR(hMonitor,;
    @nPhysMonitorCount)
 
IF nPhysMonitorCount = 0
    ? "No physical monitor detected."
    RETURN
ENDIF
 
* allocate space for the array
* of PHYSICAL_MONITOR structures
cPhysMonitorArray = REPLICATE(CHR(0), 4096)
 
* retrieves the physical monitors data
nResult = GetPhysicalMonitorsFromHMONITOR(hMonitor,;
    nPhysMonitorCount, @cPhysMonitorArray)
 
IF nResult = 0
    ? "GetPhysicalMonitorsFromHMONITOR() failed:",;
        GetLastError()
    RETURN
ENDIF
 
* this pseudo-handle starts with 0 and increments
* for each following physical monitor
hPhysMonitor = buf2dword(SUBSTR(cPhysMonitorArray, 1,4))
? "Physical Monitor handle:", hPhysMonitor
 
cMonitorName = SUBSTR(cPhysMonitorArray, 5)
cMonitorName = SUBSTR(m.cMonitorName, 1,;
    AT(CHR(0)+CHR(0), cMonitorName))
? "Monitor name:", STRCONV(cMonitorName,6)
 
LOCAL capMonitor, capColorTemp
STORE 0 TO capMonitor, capColorTemp
 
* takes about a second to return
IF GetMonitorCapabilities(hPhysMonitor,;
    @capMonitor, @capColorTemp) <> 0
    ? "Monitor Cap flags:", capMonitor
    ? "Monitor Color Temp flags:", capColorTemp
ENDIF
 
LOCAL minBrightness, curBrightness, maxBrightness
STORE 0 TO minBrightness, curBrightness, maxBrightness
 
* retrieving the brightness value (%) for the monitor
IF GetMonitorBrightness(hPhysMonitor,;
    @minBrightness, @curBrightness, @maxBrightness) <> 0
 
    ? "Brightness min, current, max:",;
        minBrightness, curBrightness, maxBrightness
 
    * setting the brightness
    * uncomment to try
    * = SetMonitorBrightness(hPhysMonitor, 100)
ELSE
    ? "GetMonitorBrightness() failed:",;
        GetLastError()
ENDIF
 
* this is the must on exit: closes the array of open
* physical monitor handles
= DestroyPhysicalMonitors(nPhysMonitorCount,;
    @cPhysMonitorArray)
 
* end of main
 
PROCEDURE declare
    DECLARE INTEGER MonitorFromWindow IN user32;
        INTEGER hWindow, INTEGER dwFlags
 
    DECLARE INTEGER GetLastError IN kernel32
 
    DECLARE INTEGER GetMonitorCapabilities IN dxva2;
        INTEGER hMonitor, LONG @pdwMonitorCapabilities,;
        LONG @pdwSupportedColorTemperatures
 
    DECLARE INTEGER GetPhysicalMonitorsFromHMONITOR IN dxva2;
        INTEGER hMonitor, LONG dwPhysicalMonitorArraySize,;
        STRING @pPhysicalMonitorArray
 
    DECLARE INTEGER GetNumberOfPhysicalMonitorsFromHMONITOR IN dxva2;
        INTEGER hMonitor, LONG @pdwNumberOfPhysicalMonitors
 
    DECLARE INTEGER DestroyPhysicalMonitors IN dxva2;
        LONG dwPhysicalMonitorArraySize, STRING @pPhysicalMonitorArray
 
    DECLARE INTEGER GetMonitorBrightness IN dxva2;
        INTEGER hMonitor, LONG @pdwMinimumBrightness,;
        LONG @pdwCurrentBrightness, LONG @pdwMaximumBrightness
 
    DECLARE INTEGER SetMonitorBrightness IN dxva2;
        INTEGER hMonitor, LONG dwNewBrightness
 
FUNCTION buf2dword(cBuffer)
RETURN Asc(SUBSTR(cBuffer, 1,1)) + ;
    BitLShift(Asc(SUBSTR(cBuffer, 2,1)),  8) +;
    BitLShift(Asc(SUBSTR(cBuffer, 3,1)), 16) +;
    BitLShift(Asc(SUBSTR(cBuffer, 4,1)), 24)