From 10fec15751ee00ab1b1482b889c0e261fdd40e2f Mon Sep 17 00:00:00 2001
From: Maarten Bent <MaartenBent@users.noreply.github.com>
Date: Sun, 25 Aug 2019 15:27:28 +0200
Subject: [PATCH] Calculate correct font pointSize for GetNonClientMetrics

wxNativeFontInfo constructor calculates the pointSize using the main screen DPI.
But lfHeight returned by GetNonClientMetrics is based on the window DPI.
---
 src/msw/menuitem.cpp | 10 +++++++++-
 src/msw/msgdlg.cpp   | 13 +++++++++++--
 src/msw/settings.cpp | 11 ++++++++++-
 3 files changed, 30 insertions(+), 4 deletions(-)

diff --git a/src/msw/menuitem.cpp b/src/msw/menuitem.cpp
index 83733eb4aa..cbf114bb9a 100644
--- a/src/msw/menuitem.cpp
+++ b/src/msw/menuitem.cpp
@@ -392,7 +392,15 @@ void MenuDrawData::Init()
 
         Offset = -12;
 
-        Font = wxFont(wxNativeFontInfo(metrics.lfMenuFont));
+        wxNativeFontInfo info(metrics.lfMenuFont);
+        // wxNativeFontInfo constructor calculates the pointSize using the
+        // main screen DPI. But lfHeight is based on the window DPI.
+        if ( window )
+        {
+            info.pointSize = wxNativeFontInfo::GetPointSizeAtPPI(
+                                 info.lf.lfHeight, window->GetDPI().y);
+        }
+        Font = wxFont(info);
 
         Theme = false;
     }
diff --git a/src/msw/msgdlg.cpp b/src/msw/msgdlg.cpp
index 8e2a101a55..21fbfc4e4b 100644
--- a/src/msw/msgdlg.cpp
+++ b/src/msw/msgdlg.cpp
@@ -397,8 +397,17 @@ void wxMessageDialog::AdjustButtonLabels()
 wxFont wxMessageDialog::GetMessageFont()
 {
     const wxWindow* win = wxTheApp ? wxTheApp->GetTopWindow() : NULL;
-    const NONCLIENTMETRICS& ncm = wxMSWImpl::GetNonClientMetrics(win);
-    return wxNativeFontInfo(ncm.lfMessageFont);
+    wxNativeFontInfo info(wxMSWImpl::GetNonClientMetrics(win).lfMessageFont);
+
+    // wxNativeFontInfo constructor calculates the pointSize using the
+    // main screen DPI. But lfHeight is based on the window DPI.
+    if ( win )
+    {
+        info.pointSize = wxNativeFontInfo::GetPointSizeAtPPI(
+                             info.lf.lfHeight, win->GetDPI().y);
+    }
+
+    return info;
 }
 
 int wxMessageDialog::ShowMessageBox()
diff --git a/src/msw/settings.cpp b/src/msw/settings.cpp
index fc1783c1ac..c2029cc67f 100644
--- a/src/msw/settings.cpp
+++ b/src/msw/settings.cpp
@@ -183,8 +183,17 @@ wxFont wxSystemSettingsNative::GetFont(wxSystemFont index)
             // controls may prefer to use lfStatusFont or lfCaptionFont if it
             // is more appropriate for them
             const wxWindow* win = wxTheApp ? wxTheApp->GetTopWindow() : NULL;
-            const wxNativeFontInfo
+            wxNativeFontInfo
                 info(wxMSWImpl::GetNonClientMetrics(win).lfMessageFont);
+
+            // wxNativeFontInfo constructor calculates the pointSize using the
+            // main screen DPI. But lfHeight is based on the window DPI.
+            if ( win )
+            {
+                info.pointSize = wxNativeFontInfo::GetPointSizeAtPPI(
+                                     info.lf.lfHeight, win->GetDPI().y);
+            }
+
             gs_fontDefault = new wxFont(info);
         }