MFC 适配DPI （win7系统 + vs2015）

[zlxi]

在win7下开发的程序，移动2k，3K屏幕上，字体变小，BITMAP 图像也缩小了。根据dpi修改字体大小，和加载不一样的图像

[zgl7903]

Setting the default DPI awareness for a process

[zlxi]

引用 1 楼 zgl7903 的回复:

Setting the default DPI awareness for a process

win8 系统以上才行，win7 系统没有相关接口

[zlxi]

引用 3 楼 schlafenhamster 的回复:

// Codes are shown here for reading ! not tested !
void CVcDispResDlg::ChangeResolution()
{
	if(!m_bAllowToChange) return;
//
	LPCTSTR psz;
	UINT nMBBtn;
	// Keep the current refresh rate
	m_DevSelect.dmDisplayFrequency = GetDeviceCaps((HDC)GetDC(), VREFRESH);
	// Attempt to change the display resolution.
	switch (ChangeDisplaySettings(&m_DevSelect, CDS_UPDATEREGISTRY))
	{
	case DISP_CHANGE_SUCCESSFUL:
		psz = __TEXT("Display change successful."); 
		break;
		
	case DISP_CHANGE_RESTART:
		psz = __TEXT("You must restart your computer before the ")
			  __TEXT("new settings will take effect.\n\n")
			  __TEXT("Do you want to restart your computer now?"); 
		nMBBtn = MB_YESNO; 
		break;
		
	case DISP_CHANGE_BADFLAGS:
		psz = __TEXT("An invalid set of flags was passed in."); 
		break;
		
	case DISP_CHANGE_FAILED:
		psz =__TEXT("The display driver couldn't change the display.");
		break;
		
	case DISP_CHANGE_BADMODE:
		psz = __TEXT("Invalid settings."); 
		break;
		
	case DISP_CHANGE_NOTUPDATED:
		psz = __TEXT("Unable to write settings to the registry."); 
		break;
	}
	// Show the user the results
	if (IDYES == AfxMessageBox( psz, nMBBtn | MB_ICONINFORMATION))
	{   // If the user wants to reboot the computer, do so.
        // Windows NT: We must enable our shutdown privilege,assumming we have it.
        // Windows 95: OpenProcessToken, LookupPrivilegeValue, and 
        //             AdjustTokenPrivileges are not implemented and
        //             are ignored.
        HANDLE hToken;
        TOKEN_PRIVILEGES tkp;
        // We want to adjust our process's privileges.
        OpenProcessToken(GetCurrentProcess(), TOKEN_ADJUST_PRIVILEGES, &hToken);
        // Get the LUID for shutdown privilege
        LookupPrivilegeValue(NULL, SE_SHUTDOWN_NAME, &tkp.Privileges[0].Luid);
        tkp.PrivilegeCount = 1;  // one privilege to set
        tkp.Privileges[0].Attributes = SE_PRIVILEGE_ENABLED;
        // Turn the SE_SHUTDOWN_NAME privilege on for our process
        AdjustTokenPrivileges(hToken, FALSE, &tkp, 0, NULL, 0);
        CloseHandle(hToken);
        // Shut down and reboot the system.
        ExitWindowsEx(EWX_REBOOT, 0);
	}
}

DEVMODE The DEVMODE data structure contains information about the device initialization and environment of a printer. typedef struct _devicemode { // dvmd BCHAR dmDeviceName[CCHDEVICENAME]; WORD dmSpecVersion; WORD dmDriverVersion; WORD dmSize; WORD dmDriverExtra; DWORD dmFields; union { struct { short dmOrientation; short dmPaperSize; short dmPaperLength; short dmPaperWidth; }; POINTL dmPosition; }; short dmScale; short dmCopies; short dmDefaultSource; short dmPrintQuality; short dmColor; short dmDuplex; short dmYResolution; short dmTTOption; short dmCollate; BCHAR dmFormName[CCHFORMNAME]; WORD dmLogPixels; DWORD dmBitsPerPel; DWORD dmPelsWidth; DWORD dmPelsHeight; DWORD dmDisplayFlags; DWORD dmDisplayFrequency; #if(WINVER >= 0x0400) DWORD dmICMMethod; DWORD dmICMIntent; DWORD dmMediaType; DWORD dmDitherType; DWORD dmReserved1; DWORD dmReserved2; #if (WINVER >= 0x0500) || (_WIN32_WINNT >= 0x0400) DWORD dmPanningWidth; DWORD dmPanningHeight; #endif #endif /* WINVER >= 0x0400 */ } DEVMODE; DEVMODE m_DevSelect;

麻烦描述一下，看功能好像修改屏幕分辨率。 不能修改屏幕分辨率

[zlxi]

引用 1 楼 zgl7903 的回复:

Setting the default DPI awareness for a process

https://bbs.csdn.net/topics/40373091 这里有讲一个，没看明白 ，大神能否帮忙解释一下

[schlafenhamster]

// Codes are shown here for reading ! not tested !
void CVcDispResDlg::ChangeResolution()
{
	if(!m_bAllowToChange) return;
//
	LPCTSTR psz;
	UINT nMBBtn;
	// Keep the current refresh rate
	m_DevSelect.dmDisplayFrequency = GetDeviceCaps((HDC)GetDC(), VREFRESH);
	// Attempt to change the display resolution.
	switch (ChangeDisplaySettings(&m_DevSelect, CDS_UPDATEREGISTRY))
	{
	case DISP_CHANGE_SUCCESSFUL:
		psz = __TEXT("Display change successful."); 
		break;
		
	case DISP_CHANGE_RESTART:
		psz = __TEXT("You must restart your computer before the ")
			  __TEXT("new settings will take effect.\n\n")
			  __TEXT("Do you want to restart your computer now?"); 
		nMBBtn = MB_YESNO; 
		break;
		
	case DISP_CHANGE_BADFLAGS:
		psz = __TEXT("An invalid set of flags was passed in."); 
		break;
		
	case DISP_CHANGE_FAILED:
		psz =__TEXT("The display driver couldn't change the display.");
		break;
		
	case DISP_CHANGE_BADMODE:
		psz = __TEXT("Invalid settings."); 
		break;
		
	case DISP_CHANGE_NOTUPDATED:
		psz = __TEXT("Unable to write settings to the registry."); 
		break;
	}
	// Show the user the results
	if (IDYES == AfxMessageBox( psz, nMBBtn | MB_ICONINFORMATION))
	{   // If the user wants to reboot the computer, do so.
        // Windows NT: We must enable our shutdown privilege,assumming we have it.
        // Windows 95: OpenProcessToken, LookupPrivilegeValue, and 
        //             AdjustTokenPrivileges are not implemented and
        //             are ignored.
        HANDLE hToken;
        TOKEN_PRIVILEGES tkp;
        // We want to adjust our process's privileges.
        OpenProcessToken(GetCurrentProcess(), TOKEN_ADJUST_PRIVILEGES, &hToken);
        // Get the LUID for shutdown privilege
        LookupPrivilegeValue(NULL, SE_SHUTDOWN_NAME, &tkp.Privileges[0].Luid);
        tkp.PrivilegeCount = 1;  // one privilege to set
        tkp.Privileges[0].Attributes = SE_PRIVILEGE_ENABLED;
        // Turn the SE_SHUTDOWN_NAME privilege on for our process
        AdjustTokenPrivileges(hToken, FALSE, &tkp, 0, NULL, 0);
        CloseHandle(hToken);
        // Shut down and reboot the system.
        ExitWindowsEx(EWX_REBOOT, 0);
	}
}

DEVMODE
The DEVMODE data structure contains information about the device initialization and environment of a printer.

typedef struct _devicemode { // dvmd
BCHAR dmDeviceName[CCHDEVICENAME];
WORD dmSpecVersion;
WORD dmDriverVersion;
WORD dmSize;
WORD dmDriverExtra;
DWORD dmFields;
union {
struct {
short dmOrientation;
short dmPaperSize;
short dmPaperLength;
short dmPaperWidth;
};
POINTL dmPosition;
};
short dmScale;
short dmCopies;
short dmDefaultSource;
short dmPrintQuality;
short dmColor;
short dmDuplex;
short dmYResolution;
short dmTTOption;
short dmCollate;
BCHAR dmFormName[CCHFORMNAME];
WORD dmLogPixels;
DWORD dmBitsPerPel;
DWORD dmPelsWidth;
DWORD dmPelsHeight;
DWORD dmDisplayFlags;
DWORD dmDisplayFrequency;
#if(WINVER >= 0x0400)
DWORD dmICMMethod;
DWORD dmICMIntent;
DWORD dmMediaType;
DWORD dmDitherType;
DWORD dmReserved1;
DWORD dmReserved2;
#if (WINVER >= 0x0500) || (_WIN32_WINNT >= 0x0400)
DWORD dmPanningWidth;
DWORD dmPanningHeight;
#endif
#endif /* WINVER >= 0x0400 */
} DEVMODE;

DEVMODE m_DevSelect;

[zgl7903]

试一试修改窗口的字体大小来适配 LOGFONT 中有这样的说明 For the MM_TEXT mapping mode, you can use the following formula to specify a height for a font with a given point size: lfHeight = -MulDiv(PointSize, GetDeviceCaps(hDC, LOGPIXELSY), 72);

[zlxi]

引用 6 楼 zgl7903 的回复:

试一试修改窗口的字体大小来适配 LOGFONT 中有这样的说明 For the MM_TEXT mapping mode, you can use the following formula to specify a height for a font with a given point size: lfHeight = -MulDiv(PointSize, GetDeviceCaps(hDC, LOGPIXELSY), 72);

请教 PointSize 这个是什么值，该如何获取

[zgl7903]

字号、磅与尺寸对照表