Start High-DPI support by scaling the parent window according to the DPI.

1 files changed, 117 insertions, 0 deletions

diff --git a/src/dutil/dpiutil.cpp b/src/dutil/dpiutil.cpp
new file mode 100644
index 00000000..edab8f01
--- /dev/null
+++ b/src/dutil/dpiutil.cpp
@@ -0,0 +1,117 @@
+// Copyright (c) .NET Foundation and contributors. All rights reserved. Licensed under the Microsoft Reciprocal License. See LICENSE.TXT file in the project root for full license information.
+
+#include "precomp.h"
+
+// Exit macros
+#define DpiuExitOnLastError(x, s, ...) ExitOnLastErrorSource(DUTIL_SOURCE_DPIUTIL, x, s, __VA_ARGS__)
+#define DpiuExitOnLastErrorDebugTrace(x, s, ...) ExitOnLastErrorDebugTraceSource(DUTIL_SOURCE_DPIUTIL, x, s, __VA_ARGS__)
+#define DpiuExitWithLastError(x, s, ...) ExitWithLastErrorSource(DUTIL_SOURCE_DPIUTIL, x, s, __VA_ARGS__)
+#define DpiuExitOnFailure(x, s, ...) ExitOnFailureSource(DUTIL_SOURCE_DPIUTIL, x, s, __VA_ARGS__)
+#define DpiuExitOnRootFailure(x, s, ...) ExitOnRootFailureSource(DUTIL_SOURCE_DPIUTIL, x, s, __VA_ARGS__)
+#define DpiuExitOnFailureDebugTrace(x, s, ...) ExitOnFailureDebugTraceSource(DUTIL_SOURCE_DPIUTIL, x, s, __VA_ARGS__)
+#define DpiuExitOnNull(p, x, e, s, ...) ExitOnNullSource(DUTIL_SOURCE_DPIUTIL, p, x, e, s, __VA_ARGS__)
+#define DpiuExitOnNullWithLastError(p, x, s, ...) ExitOnNullWithLastErrorSource(DUTIL_SOURCE_DPIUTIL, p, x, s, __VA_ARGS__)
+#define DpiuExitOnNullDebugTrace(p, x, e, s, ...)  ExitOnNullDebugTraceSource(DUTIL_SOURCE_DPIUTIL, p, x, e, s, __VA_ARGS__)
+#define DpiuExitOnInvalidHandleWithLastError(p, x, s, ...) ExitOnInvalidHandleWithLastErrorSource(DUTIL_SOURCE_DPIUTIL, p, x, s, __VA_ARGS__)
+#define DpiuExitOnWin32Error(e, x, s, ...) ExitOnWin32ErrorSource(DUTIL_SOURCE_DPIUTIL, e, x, s, __VA_ARGS__)
+
+static PFN_GETDPIFORMONITOR vpfnGetDpiForMonitor = NULL;
+static PFN_GETDPIFORWINDOW vpfnGetDpiForWindow = NULL;
+
+static HMODULE vhShcoreDll = NULL;
+static HMODULE vhUser32Dll = NULL;
+static BOOL vfDpiuInitialized = FALSE;
+
+DAPI_(void) DpiuInitialize()
+{
+    HRESULT hr = S_OK;
+
+    hr = LoadSystemLibrary(L"Shcore.dll", &vhShcoreDll);
+    if (SUCCEEDED(hr))
+    {
+        // Ignore failures.
+        vpfnGetDpiForMonitor = reinterpret_cast<PFN_GETDPIFORMONITOR>(::GetProcAddress(vhShcoreDll, "GetDpiForMonitor"));
+    }
+
+    hr = LoadSystemLibrary(L"User32.dll", &vhUser32Dll);
+    if (SUCCEEDED(hr))
+    {
+        // Ignore failures.
+        vpfnGetDpiForWindow = reinterpret_cast<PFN_GETDPIFORWINDOW>(::GetProcAddress(vhUser32Dll, "GetDpiForWindow"));
+    }
+
+    vfDpiuInitialized = TRUE;
+}
+
+DAPI_(void) DpiuUninitialize()
+{
+    if (vhShcoreDll)
+    {
+        ::FreeLibrary(vhShcoreDll);
+    }
+
+    if (vhUser32Dll)
+    {
+        ::FreeLibrary(vhUser32Dll);
+    }
+
+    vhShcoreDll = NULL;
+    vhUser32Dll = NULL;
+    vpfnGetDpiForMonitor = NULL;
+    vpfnGetDpiForWindow = NULL;
+    vfDpiuInitialized = FALSE;
+}
+
+DAPI_(void) DpiuGetWindowContext(
+    __in HWND hWnd,
+    __in DPIU_WINDOW_CONTEXT* pWindowContext
+    )
+{
+    HRESULT hr = S_OK;
+    HMONITOR hMonitor = NULL;
+    UINT dpiX = 0;
+    UINT dpiY = 0;
+    HDC hdc = NULL;
+
+    pWindowContext->nDpi = USER_DEFAULT_SCREEN_DPI;
+
+    if (vpfnGetDpiForWindow)
+    {
+        pWindowContext->nDpi = vpfnGetDpiForWindow(hWnd);
+        ExitFunction();
+    }
+
+    if (vpfnGetDpiForMonitor)
+    {
+        hMonitor = ::MonitorFromWindow(hWnd, MONITOR_DEFAULTTONEAREST);
+        if (hMonitor)
+        {
+            hr = vpfnGetDpiForMonitor(hMonitor, MDT_EFFECTIVE_DPI, &dpiX, &dpiY);
+            if (SUCCEEDED(hr))
+            {
+                pWindowContext->nDpi = dpiX;
+                ExitFunction();
+            }
+        }
+    }
+
+    hdc = ::GetDC(hWnd);
+    if (hdc)
+    {
+        pWindowContext->nDpi = ::GetDeviceCaps(hdc, LOGPIXELSX);
+    }
+
+LExit:
+    if (hdc)
+    {
+        ::ReleaseDC(hWnd, hdc);
+    }
+}
+
+DAPI_(int) DpiuScaleValue(
+    __in int nDefaultDpiValue,
+    __in UINT nTargetDpi
+    )
+{
+    return ::MulDiv(nDefaultDpiValue, nTargetDpi, USER_DEFAULT_SCREEN_DPI);
+}