Made DPI dynamic to fix errors where running on Win7 failed

BeefySysLib/platform/win/WinBFApp.cpp

@@ -1016,12 +1016,22 @@ static int WinBFReportHook( int reportType, char *message, int *returnValue )
 
 extern HINSTANCE gDLLInstance;
 
+typedef UINT(NTAPI *GetDpiForWindow_t)(HWND);
+static GetDpiForWindow_t gGetDpiForWindow = NULL;
+static HMODULE gUserDll = NULL;
+
 WinBFApp::WinBFApp()
 {		
 #ifndef BF_MINGW
 	//_CrtSetReportHook(WinBFReportHook);
 #endif
 
+	if (gUserDll == NULL)
+	{
+		gUserDll = ::LoadLibraryA("user32.dll");
+		gGetDpiForWindow = (GetDpiForWindow_t)::GetProcAddress(gUserDll, "GetDpiForWindow");
+	}
+
 	mRunning = false;
 	mRenderDevice = NULL;	
 
@@ -1341,6 +1351,13 @@ bool WinBFWindow::IsMouseCaptured()
 	return (mHWnd != NULL) && (GetCapture() == mHWnd);
 }
 
+int WinBFWindow::GetDPI()
+{
+	if (gGetDpiForWindow != NULL)
+		return (int)gGetDpiForWindow(mHWnd);
+	return 96; // Default DPI
+}
+
 uint32 WinBFApp::GetClipboardFormat(const StringImpl& format)
 {
 	if (format == "text")

BeefySysLib/platform/win/WinBFApp.h

@@ -75,7 +75,7 @@ public:
 	virtual void			SetAlpha(float alpha, uint32 destAlphaSrcMask, bool isMouseVisible) override;
 	virtual void			CaptureMouse() override;
 	virtual bool			IsMouseCaptured() override;
-	virtual int				GetDPI() { return ::GetDpiForWindow(mHWnd); }
+	virtual int				GetDPI() override; // { return ::GetDpiForWindow(mHWnd); }
 
 	virtual BFMenu*			AddMenuItem(BFMenu* parent, int insertIdx, const char* text, const char* hotKey, BFSysBitmap* bitmap, bool enabled, int checkState, bool radioCheck) override;
 	virtual void			ModifyMenuItem(BFMenu* item, const char* text, const char* hotKey, BFSysBitmap* bitmap, bool enabled, int checkState, bool radioCheck) override;