win7 support

Photino.Native/Photino.Native.vcxproj

@@ -159,6 +159,7 @@ COPY .\$(OutDir)WebView2Loader.dll ..\Photino.Test\bin\Debug\net5.0\</Command>
     <ClCompile Include="Photino.Linux.cpp" />
     <ClCompile Include="Photino.Windows.cpp" />
     <ClCompile Include="Photino.Windows.DarkMode.cpp" />
+    <ClCompile Include="Photino.Windows.DpiHelp.cpp" />
   </ItemGroup>
   <ItemGroup>
     <ClInclude Include="Dependencies\wintoastlib.h" />
@@ -168,6 +169,7 @@ COPY .\$(OutDir)WebView2Loader.dll ..\Photino.Test\bin\Debug\net5.0\</Command>
     <ClInclude Include="Photino.Mac.UrlSchemeHandler.h" />
     <ClInclude Include="Photino.Windows.ToastHandler.h" />
     <ClInclude Include="Photino.Windows.DarkMode.h" />
+    <ClInclude Include="Photino.Windows.DpiHelp.h" />
   </ItemGroup>
   <ItemGroup>
     <None Include="packages.config" />

Photino.Native/Photino.Native.vcxproj.filters

@@ -30,6 +30,9 @@
     <ClCompile Include="Photino.Windows.DarkMode.cpp">
       <Filter>Source Files</Filter>
     </ClCompile>
+    <ClCompile Include="Photino.Windows.DpiHelp.cpp">
+      <Filter>Source Files</Filter>
+    </ClCompile>
   </ItemGroup>
   <ItemGroup>
     <None Include="packages.config" />
@@ -69,5 +72,8 @@
     <ClInclude Include="Photino.Windows.DarkMode.h">
       <Filter>Source Files</Filter>
     </ClInclude>
+    <ClInclude Include="Photino.Windows.DpiHelp.h">
+      <Filter>Header Files</Filter>
+    </ClInclude>
   </ItemGroup>
 </Project>

Photino.Native/Photino.Windows.DpiHelp.cpp

@@ -0,0 +1,124 @@
+#include "Photino.Windows.DpiHelp.h"
+
+// =============================================
+//
+// Types
+//
+// ===================
+typedef UINT(WINAPI *_GetDpiForWindowFunc)(HWND hwnd);
+typedef DPI_AWARENESS_CONTEXT(WINAPI *_SetThreadDpiAwarenessContextFunc)(DPI_AWARENESS_CONTEXT dpiContext);
+typedef int(WINAPI *_GetSystemMetricsForDpiFunc)(int nIndex, UINT dpi);
+
+// =============================================
+//
+// Forward declarations
+//
+// ===================
+UINT FallbackGetDpiForWindow(HWND hwnd);
+DPI_AWARENESS_CONTEXT FallbackSetThreadDpiAwarenessContext(DPI_AWARENESS_CONTEXT dpiContext);
+int FallbackGetSystemMetricsForDpiFunc(int nIndex, UINT dpi);
+
+// =============================================
+//
+// Statics
+//
+// ===================
+static HMODULE s_user32 = nullptr;
+
+static _GetDpiForWindowFunc _getDpiForWindow = FallbackGetDpiForWindow;
+static _GetSystemMetricsForDpiFunc _getSystemMetricsForDpi = FallbackGetSystemMetricsForDpiFunc;
+static _SetThreadDpiAwarenessContextFunc _setThreadDpiAwarenessContext = FallbackSetThreadDpiAwarenessContext;
+
+// =============================================
+//
+// Helpers
+//
+// ===================
+static UINT FallbackGetDpiForWindow(HWND hwnd)
+{
+	return 96;
+}
+
+static DPI_AWARENESS_CONTEXT FallbackSetThreadDpiAwarenessContext(DPI_AWARENESS_CONTEXT dpiContext)
+{
+	return nullptr;
+}
+
+static int FallbackGetSystemMetricsForDpiFunc(int nIndex, UINT dpi)
+{
+	return GetSystemMetrics(nIndex);
+}
+
+static void SetFallbacks()
+{
+	_getDpiForWindow = FallbackGetDpiForWindow;
+	_getSystemMetricsForDpi = FallbackGetSystemMetricsForDpiFunc;
+	_setThreadDpiAwarenessContext = FallbackSetThreadDpiAwarenessContext;
+}
+
+// =============================================	
+//
+// Exports
+//
+// ===================
+void CloseDpiHelper()
+{
+	SetFallbacks();
+
+	if (s_user32 != nullptr)
+	{
+		FreeLibrary(s_user32);
+		s_user32 = nullptr;
+	}
+}
+
+int GetScreenHeight(int dpi)
+{
+	return _getSystemMetricsForDpi(SM_CYSCREEN, dpi);
+}
+
+int GetScreenWidth(int dpi)
+{
+	return _getSystemMetricsForDpi(SM_CXSCREEN, dpi);
+}
+
+unsigned int GetWindowDpi(HWND hwnd)
+{
+	return _getDpiForWindow(hwnd);
+}
+
+void InitDpiHelper()
+{
+	SetFallbacks();
+
+	s_user32 = LoadLibrary(L"User32.dll");
+	if (s_user32 == nullptr)
+	{
+		return;
+	}
+
+	auto win10GetDpiForWindow = (_GetDpiForWindowFunc)GetProcAddress(s_user32, "GetDpiForWindow");
+	if (win10GetDpiForWindow != nullptr)
+	{
+		_getDpiForWindow = win10GetDpiForWindow;
+	}
+
+	auto win10GetSystemMetricsForDpi = (_GetSystemMetricsForDpiFunc)GetProcAddress(s_user32, "GetSystemMetricsForDpi");
+	if (win10GetSystemMetricsForDpi != nullptr)
+	{
+		_getSystemMetricsForDpi = win10GetSystemMetricsForDpi;
+	}
+
+	auto win10SetThreadDpiAwarenessContext = (_SetThreadDpiAwarenessContextFunc)GetProcAddress(s_user32, "SetThreadDpiAwarenessContext");
+	if (win10SetThreadDpiAwarenessContext != nullptr)
+	{
+		auto oldVal = win10SetThreadDpiAwarenessContext(DPI_AWARENESS_CONTEXT_PER_MONITOR_AWARE);
+		if (oldVal == nullptr)
+		{
+			CloseDpiHelper(); // failed init of the win10+ apis
+			return;
+		}
+
+		_setThreadDpiAwarenessContext = win10SetThreadDpiAwarenessContext;
+	}
+}

Photino.Native/Photino.Windows.DpiHelp.h

@@ -0,0 +1,9 @@
+#pragma once
+
+#include <Windows.h>
+
+void CloseDpiHelper();
+int GetScreenHeight(int dpi);
+int GetScreenWidth(int dpi);
+unsigned int GetWindowDpi(HWND hwnd);
+void InitDpiHelper();

Photino.Native/Photino.Windows.cpp

@@ -10,6 +10,10 @@
 
 #include "Photino.Windows.DarkMode.h"
 
+#ifdef COMPAT_DPI
+#include "Photino.Windows.DpiHelp.h"
+#endif
+
 #pragma comment(lib, "Urlmon.lib")
 #pragma warning(disable: 4996)		//disable warning about wcscpy vs. wcscpy_s
 
@@ -65,7 +69,11 @@ void Photino::Register(HINSTANCE hInstance)
 
 	RegisterClassEx(&wcx);
 
+#ifdef COMPAT_DPI
+	InitDpiHelper();
+#else
 	SetThreadDpiAwarenessContext(DPI_AWARENESS_CONTEXT_PER_MONITOR_AWARE);
+#endif
 }
 
 
@@ -232,6 +240,10 @@ Photino::Photino(PhotinoInitParams* initParams)
 
 Photino::~Photino()
 {
+#ifdef COMPAT_DPI
+	CloseDpiHelper();
+#endif
+
 	if (_startUrl != NULL) delete[]_startUrl;
 	if (_startString != NULL) delete[]_startString;
 	if (_temporaryFilesPath != NULL) delete[]_temporaryFilesPath;
@@ -370,9 +382,15 @@ LRESULT CALLBACK WindowProc(HWND hwnd, UINT uMsg, WPARAM wParam, LPARAM lParam)
 
 void Photino::Center()
 {
+#ifdef COMPAT_DPI
+	int screenDpi = GetWindowDpi(_hWnd);
+	int screenHeight = GetScreenHeight(screenDpi);
+	int screenWidth = GetScreenWidth(screenDpi);
+#else
 	int screenDpi = GetDpiForWindow(_hWnd);
 	int screenHeight = GetSystemMetricsForDpi(SM_CYSCREEN, screenDpi);
 	int screenWidth = GetSystemMetricsForDpi(SM_CXSCREEN, screenDpi);
+#endif
 
 	RECT windowRect = {};
 	GetWindowRect(_hWnd, &windowRect);
@@ -454,7 +472,11 @@ void Photino::GetResizable(bool* resizable)
 
 unsigned int Photino::GetScreenDpi()
 {
+#ifdef COMPAT_DPI
+	return GetWindowDpi(_hWnd);
+#else
 	return GetDpiForWindow(_hWnd);
+#endif
 }
 
 void Photino::GetSize(int* width, int* height)

Photino.Native/Photino.h

@@ -1,6 +1,14 @@
 #pragma once
 
 #ifdef _WIN32
+
+#define COMPAT_DPI
+
+#ifdef COMPAT_DPI
+#define WINVER _WIN32_WINNT_WIN7
+#define _WIN32_WINNT _WIN32_WINNT_WIN7
+#endif
+
 #include <Windows.h>
 #include <wil/com.h>
 #include <WebView2.h>