Fix printing with unhinted fonts

On high-dpi displays or when you explicitly select an unhinted font,
we pick a DirectWrite font engine. This hit an uncovered code path
on Windows, because we relied on being able to get the HFONT from
the font engine.

To fix this, we introduce an alternative code path which gets the
HFONT based on the DirectWrite font when this font engine is active.

[ChangeLog][Windows] Fixed an issue where the characters in printed
text would look too small.

Pick-to: 6.1 6.2
Fixes: QTBUG-95720
Change-Id: Ifd609e92512e1f25f0ee2aace35cb5ccedf09030
Reviewed-by: Lars Knoll <lars.knoll@qt.io>

1 files changed, 16 insertions, 0 deletions

diff --git a/src/gui/text/windows/qwindowsfontenginedirectwrite.cpp b/src/gui/text/windows/qwindowsfontenginedirectwrite.cpp
index 0dac9769ef..55aab15132 100644
--- a/src/gui/text/windows/qwindowsfontenginedirectwrite.cpp
+++ b/src/gui/text/windows/qwindowsfontenginedirectwrite.cpp
@@ -337,6 +337,22 @@ QString QWindowsFontEngineDirectWrite::filenameFromFontFile(IDWriteFontFile *fon
     return ret;
 }
 
+HFONT QWindowsFontEngineDirectWrite::createHFONT() const
+{
+    if (m_fontEngineData == nullptr || m_directWriteFontFace == nullptr)
+        return NULL;
+
+    LOGFONT lf;
+    HRESULT hr = m_fontEngineData->directWriteGdiInterop->ConvertFontFaceToLOGFONT(m_directWriteFontFace,
+                                                                                   &lf);
+    if (SUCCEEDED(hr)) {
+        lf.lfHeight = -qRound(fontDef.pixelSize);
+        return CreateFontIndirect(&lf);
+    } else {
+        return NULL;
+    }
+}
+
 void QWindowsFontEngineDirectWrite::initializeHeightMetrics() const
 {
     DWRITE_FONT_METRICS metrics;