Fix QGlyphRun text rendering

When drawing QGlyphRun objects through QPainter the QFont passed in
QStaticTextItem/QTextItem is not properly initialized with the correct
size, weight, style strategy etc. Shuffle things around so we always go
through QFontEngine for font data, as that should be more reliable.

Change-Id: I43811c868ebd4fb1d9e937ee28a6d637267b4c7f
Reviewed-by: Risto Avila <risto.avila@digia.com>
Reviewed-by: Andrew Knight <andrew.knight@digia.com>

2 files changed, 95 insertions, 129 deletions

diff --git a/src/plugins/platforms/direct2d/qwindowsdirect2dpaintengine.cpp b/src/plugins/platforms/direct2d/qwindowsdirect2dpaintengine.cpp
index 4c39560cbe..f131419140 100644
--- a/src/plugins/platforms/direct2d/qwindowsdirect2dpaintengine.cpp
+++ b/src/plugins/platforms/direct2d/qwindowsdirect2dpaintengine.cpp
@@ -48,11 +48,11 @@
 #include "qwindowsdirect2ddevicecontext.h"
 
 #include "qwindowsfontengine.h"
-#include "qwindowsfontenginedirectwrite.h"
 #include "qwindowsfontdatabase.h"
 #include "qwindowsintegration.h"
 
 #include <QtCore/QStack>
+#include <QtCore/QSettings>
 #include <QtGui/private/qpaintengine_p.h>
 #include <QtGui/private/qtextengine_p.h>
 #include <QtGui/private/qfontengine_p.h>
@@ -109,6 +109,13 @@ static inline ID2D1Factory1 *factory()
     return QWindowsDirect2DContext::instance()->d2dFactory();
 }
 
+inline static FLOAT pixelSizeToDIP(int pixelSize)
+{
+    FLOAT dpiX, dpiY;
+    QWindowsDirect2DContext::instance()->d2dFactory()->GetDesktopDpi(&dpiX, &dpiY);
+    return FLOAT(pixelSize) * 96.0f / dpiY;
+}
+
 class Direct2DPathGeometryWriter
 {
 public:
@@ -243,7 +250,7 @@ public:
 
     QPointF currentBrushOrigin;
 
-    QHash< QFont, ComPtr<IDWriteFontFace> > fontCache;
+    QHash< QFontDef, ComPtr<IDWriteFontFace> > fontCache;
 
     struct {
         bool emulate;
@@ -836,6 +843,74 @@ public:
     {
         dc()->SetAntialiasMode(antialiasMode());
     }
+
+    void drawGlyphRun(const D2D1_POINT_2F &pos,
+                      IDWriteFontFace *fontFace,
+                      const QFontDef &fontDef,
+                      int numGlyphs,
+                      const UINT16 *glyphIndices,
+                      const FLOAT *glyphAdvances,
+                      const DWRITE_GLYPH_OFFSET *glyphOffsets,
+                      bool rtl)
+    {
+        Q_Q(QWindowsDirect2DPaintEngine);
+
+        DWRITE_GLYPH_RUN glyphRun = {
+            fontFace,                           //    IDWriteFontFace           *fontFace;
+            pixelSizeToDIP(fontDef.pixelSize),  //    FLOAT                     fontEmSize;
+            numGlyphs,                          //    UINT32                    glyphCount;
+            glyphIndices,                       //    const UINT16              *glyphIndices;
+            glyphAdvances,                      //    const FLOAT               *glyphAdvances;
+            glyphOffsets,                       //    const DWRITE_GLYPH_OFFSET *glyphOffsets;
+            FALSE,                              //    BOOL                      isSideways;
+            rtl ? 1 : 0                         //    UINT32                    bidiLevel;
+        };
+
+        const bool antiAlias = bool((q->state()->renderHints & QPainter::TextAntialiasing)
+                                    && !(fontDef.styleStrategy & QFont::NoAntialias));
+        dc()->SetTextAntialiasMode(antiAlias ? D2D1_TEXT_ANTIALIAS_MODE_CLEARTYPE
+                                             : D2D1_TEXT_ANTIALIAS_MODE_ALIASED);
+
+        dc()->DrawGlyphRun(pos,
+                           &glyphRun,
+                           NULL,
+                           pen.brush.Get(),
+                           DWRITE_MEASURING_MODE_GDI_CLASSIC);
+    }
+
+    ComPtr<IDWriteFontFace> fontFaceFromFontEngine(QFontEngine *fe)
+    {
+        const QFontDef fontDef = fe->fontDef;
+        ComPtr<IDWriteFontFace> fontFace = fontCache.value(fontDef);
+        if (fontFace)
+            return fontFace;
+
+        LOGFONT lf = QWindowsFontDatabase::fontDefToLOGFONT(fontDef);
+
+        // Get substitute name
+        static const char keyC[] = "HKEY_LOCAL_MACHINE\\Software\\Microsoft\\Windows NT\\CurrentVersion\\FontSubstitutes";
+        const QString familyName = QString::fromWCharArray(lf.lfFaceName);
+        const QString nameSubstitute = QSettings(QLatin1String(keyC), QSettings::NativeFormat).value(familyName, familyName).toString();
+        memcpy(lf.lfFaceName, nameSubstitute.utf16(), sizeof(wchar_t) * qMin(nameSubstitute.length() + 1, LF_FACESIZE));
+
+        ComPtr<IDWriteFont> dwriteFont;
+        HRESULT hr = QWindowsDirect2DContext::instance()->dwriteGdiInterop()->CreateFontFromLOGFONT(&lf, &dwriteFont);
+        if (FAILED(hr)) {
+            qDebug("%s: CreateFontFromLOGFONT failed: %#x", __FUNCTION__, hr);
+            return fontFace;
+        }
+
+        hr = dwriteFont->CreateFontFace(&fontFace);
+        if (FAILED(hr)) {
+            qDebug("%s: CreateFontFace failed: %#x", __FUNCTION__, hr);
+            return fontFace;
+        }
+
+        if (fontFace)
+            fontCache.insert(fontDef, fontFace);
+
+        return fontFace;
+    }
 };
 
 QWindowsDirect2DPaintEngine::QWindowsDirect2DPaintEngine(QWindowsDirect2DBitmap *bitmap)
@@ -1411,7 +1486,7 @@ void QWindowsDirect2DPaintEngine::drawStaticTextItem(QStaticTextItem *staticText
         return;
     }
 
-    ComPtr<IDWriteFontFace> fontFace = fontFaceFromFontEngine(staticTextItem->font, staticTextItem->fontEngine());
+    ComPtr<IDWriteFontFace> fontFace = d->fontFaceFromFontEngine(staticTextItem->fontEngine());
     if (!fontFace) {
         qWarning("%s: Could not find font - falling back to slow text rendering path.", __FUNCTION__);
         QPaintEngineEx::drawStaticTextItem(staticTextItem);
@@ -1432,14 +1507,14 @@ void QWindowsDirect2DPaintEngine::drawStaticTextItem(QStaticTextItem *staticText
         glyphOffsets[i].ascenderOffset = staticTextItem->glyphPositions[i].y.toReal() * -1;
     }
 
-    drawGlyphRun(D2D1::Point2F(0, 0),
-                 fontFace.Get(),
-                 staticTextItem->font,
-                 staticTextItem->numGlyphs,
-                 glyphIndices.constData(),
-                 glyphAdvances.constData(),
-                 glyphOffsets.constData(),
-                 false);
+    d->drawGlyphRun(D2D1::Point2F(0, 0),
+                    fontFace.Get(),
+                    staticTextItem->fontEngine()->fontDef,
+                    staticTextItem->numGlyphs,
+                    glyphIndices.constData(),
+                    glyphAdvances.constData(),
+                    glyphOffsets.constData(),
+                    false);
 }
 
 void QWindowsDirect2DPaintEngine::drawTextItem(const QPointF &p, const QTextItem &textItem)
@@ -1459,7 +1534,7 @@ void QWindowsDirect2DPaintEngine::drawTextItem(const QPointF &p, const QTextItem
         return;
     }
 
-    ComPtr<IDWriteFontFace> fontFace = fontFaceFromFontEngine(*ti.f, ti.fontEngine);
+    ComPtr<IDWriteFontFace> fontFace = d->fontFaceFromFontEngine(ti.fontEngine);
     if (!fontFace) {
         qWarning("%s: Could not find font - falling back to slow text rendering path.", __FUNCTION__);
         QPaintEngine::drawTextItem(p, textItem);
@@ -1482,72 +1557,14 @@ void QWindowsDirect2DPaintEngine::drawTextItem(const QPointF &p, const QTextItem
     const bool rtl = (ti.flags & QTextItem::RightToLeft);
     const QPointF offset(rtl ? ti.width.toReal() : 0, 0);
 
-    drawGlyphRun(to_d2d_point_2f(p + offset),
-                 fontFace.Get(),
-                 ti.font(),
-                 ti.glyphs.numGlyphs,
-                 glyphIndices.constData(),
-                 glyphAdvances.constData(),
-                 glyphOffsets.constData(),
-                 rtl);
-}
-
-inline static FLOAT pointSizeToDIP(qreal pointSize, FLOAT dpiY)
-{
-    return (pointSize + (pointSize / qreal(3.0))) * (dpiY / 96.0f);
-}
-
-inline static FLOAT pixelSizeToDIP(int pixelSize, FLOAT dpiY)
-{
-    return FLOAT(pixelSize) * 96.0f / dpiY;
-}
-
-inline static FLOAT fontSizeInDIP(const QFont &font)
-{
-    FLOAT dpiX, dpiY;
-    QWindowsDirect2DContext::instance()->d2dFactory()->GetDesktopDpi(&dpiX, &dpiY);
-
-    if (font.pixelSize() == -1) {
-        // font size was set as points
-        return pointSizeToDIP(font.pointSizeF(), dpiY);
-    } else {
-        // font size was set as pixels
-        return pixelSizeToDIP(font.pixelSize(), dpiY);
-    }
-}
-
-void QWindowsDirect2DPaintEngine::drawGlyphRun(const D2D1_POINT_2F &pos,
-                                               IDWriteFontFace *fontFace,
-                                               const QFont &font,
-                                               int numGlyphs,
-                                               const UINT16 *glyphIndices,
-                                               const FLOAT *glyphAdvances,
-                                               const DWRITE_GLYPH_OFFSET *glyphOffsets,
-                                               bool rtl)
-{
-    Q_D(QWindowsDirect2DPaintEngine);
-
-    DWRITE_GLYPH_RUN glyphRun = {
-        fontFace,               //    IDWriteFontFace           *fontFace;
-        fontSizeInDIP(font),    //    FLOAT                     fontEmSize;
-        numGlyphs,              //    UINT32                    glyphCount;
-        glyphIndices,           //    const UINT16              *glyphIndices;
-        glyphAdvances,          //    const FLOAT               *glyphAdvances;
-        glyphOffsets,           //    const DWRITE_GLYPH_OFFSET *glyphOffsets;
-        FALSE,                  //    BOOL                      isSideways;
-        rtl ? 1 : 0             //    UINT32                    bidiLevel;
-    };
-
-    const bool antiAlias = bool((state()->renderHints & QPainter::TextAntialiasing)
-                                && !(font.styleStrategy() & QFont::NoAntialias));
-    d->dc()->SetTextAntialiasMode(antiAlias ? D2D1_TEXT_ANTIALIAS_MODE_CLEARTYPE
-                                            : D2D1_TEXT_ANTIALIAS_MODE_ALIASED);
-
-    d->dc()->DrawGlyphRun(pos,
-                          &glyphRun,
-                          NULL,
-                          d->pen.brush.Get(),
-                          DWRITE_MEASURING_MODE_GDI_CLASSIC);
+    d->drawGlyphRun(to_d2d_point_2f(p + offset),
+                    fontFace.Get(),
+                    ti.fontEngine->fontDef,
+                    ti.glyphs.numGlyphs,
+                    glyphIndices.constData(),
+                    glyphAdvances.constData(),
+                    glyphOffsets.constData(),
+                    rtl);
 }
 
 void QWindowsDirect2DPaintEngine::ensureBrush()
@@ -1678,49 +1695,4 @@ void QWindowsDirect2DPaintEngine::adjustForAliasing(QPointF *point)
         (*point) += adjustment;
 }
 
-Microsoft::WRL::ComPtr<IDWriteFontFace> QWindowsDirect2DPaintEngine::fontFaceFromFontEngine(const QFont &font, QFontEngine *fe)
-{
-    Q_D(QWindowsDirect2DPaintEngine);
-
-    ComPtr<IDWriteFontFace> fontFace = d->fontCache.value(font);
-    if (fontFace)
-        return fontFace;
-
-    switch (fe->type()) {
-    case QFontEngine::Win:
-    {
-        QWindowsFontEngine *wfe = static_cast<QWindowsFontEngine *>(fe);
-        QSharedPointer<QWindowsFontEngineData> wfed = wfe->fontEngineData();
-
-        HGDIOBJ oldfont = wfe->selectDesignFont();
-        HRESULT hr = QWindowsDirect2DContext::instance()->dwriteGdiInterop()->CreateFontFaceFromHdc(wfed->hdc, &fontFace);
-        DeleteObject(SelectObject(wfed->hdc, oldfont));
-        if (FAILED(hr))
-            qWarning("%s: Could not create DirectWrite fontface from HDC: %#x", __FUNCTION__, hr);
-
-    }
-        break;
-
-#ifndef QT_NO_DIRECTWRITE
-
-    case QFontEngine::DirectWrite:
-    {
-        QWindowsFontEngineDirectWrite *wfedw = static_cast<QWindowsFontEngineDirectWrite *>(fe);
-        fontFace = wfedw->directWriteFontFace();
-    }
-        break;
-
-#endif // QT_NO_DIRECTWRITE
-
-    default:
-        qWarning("%s: Unknown font engine!", __FUNCTION__);
-        break;
-    }
-
-    if (fontFace)
-        d->fontCache.insert(font, fontFace);
-
-    return fontFace;
-}
-
 QT_END_NAMESPACE
diff --git a/src/plugins/platforms/direct2d/qwindowsdirect2dpaintengine.h b/src/plugins/platforms/direct2d/qwindowsdirect2dpaintengine.h
index c91a951ebe..1469d32876 100644
--- a/src/plugins/platforms/direct2d/qwindowsdirect2dpaintengine.h
+++ b/src/plugins/platforms/direct2d/qwindowsdirect2dpaintengine.h
@@ -105,10 +105,6 @@ public:
     void drawTextItem(const QPointF &p, const QTextItem &textItem) Q_DECL_OVERRIDE;
 
 private:
-    void drawGlyphRun(const D2D1_POINT_2F &pos, IDWriteFontFace *fontFace, const QFont &font,
-                      int numGlyphs, const UINT16 *glyphIndices, const FLOAT *glyphAdvances,
-                      const DWRITE_GLYPH_OFFSET *glyphOffsets, bool rtl);
-
     void ensureBrush();
     void ensureBrush(const QBrush &brush);
     void ensurePen();
@@ -122,8 +118,6 @@ private:
     bool antiAliasingEnabled() const;
     void adjustForAliasing(QRectF *rect);
     void adjustForAliasing(QPointF *point);
-
-    Microsoft::WRL::ComPtr<IDWriteFontFace> fontFaceFromFontEngine(const QFont &font, QFontEngine *fe);
 };
 
 QT_END_NAMESPACE