tdf#161154: pass "scaling is done externally" information down the stack

VclProcessor2D::RenderTextSimpleOrDecoratedPortionPrimitive2D does the
scaling, taking into account the font scaling. Before commit
8557ea84c9336ba8061246f1f46ddb6e02f413a1, D2DWriteTextOutRenderer was
doing own scaling in addition, but it seems that it somehow didn't
affect the result much. The said commit removed the scalng from
D2DWriteTextOutRenderer. As tdf#160901 demonstrated, the scaling is
necessary in different code paths - and it turns out, that we need to
know, if the caller does its own scaling or not, to make a decision,
if the scaling should be fone in D2DWriteTextOutRenderer.

This hack passes this from VclProcessor2D to D2DWriteTextOutRenderer
through OutputDevice. Thanks to Miklos for the isea. I still don't
understand, why all this seemingly doesn't affect other renderers.

Change-Id: I001036f4574898b8e7606652525638df43c35240
Reviewed-on: https://gerrit.libreoffice.org/c/core/+/167786
Reviewed-by: Mike Kaganski <mike.kaganski@collabora.com>
Tested-by: Jenkins

5 files changed, 31 insertions, 14 deletions

diff --git a/drawinglayer/source/processor2d/vclprocessor2d.cxx b/drawinglayer/source/processor2d/vclprocessor2d.cxx
index f7a21a8e698c..f6b8dbc8f953 100644
--- a/drawinglayer/source/processor2d/vclprocessor2d.cxx
+++ b/drawinglayer/source/processor2d/vclprocessor2d.cxx
@@ -441,17 +441,21 @@ void VclProcessor2D::RenderTextSimpleOrDecoratedPortionPrimitive2D(
             mpOutputDevice->SetFont(aFont);
             mpOutputDevice->SetTextColor(Color(aRGBFontColor));
 
-            if (!aDXArray.empty())
             {
-                const SalLayoutGlyphs* pGlyphs = SalLayoutGlyphsCache::self()->GetLayoutGlyphs(
-                    mpOutputDevice, aText, nPos, nLen);
-                mpOutputDevice->DrawTextArray(aStartPoint, aText, aDXArray,
-                                              rTextCandidate.getKashidaArray(), nPos, nLen,
-                                              SalLayoutFlags::NONE, pGlyphs);
-            }
-            else
-            {
-                mpOutputDevice->DrawText(aStartPoint, aText, nPos, nLen);
+                // For D2DWriteTextOutRenderer, we must pass a flag to not use font scaling
+                auto guard = mpOutputDevice->ScopedNoFontScaling();
+                if (!aDXArray.empty())
+                {
+                    const SalLayoutGlyphs* pGlyphs = SalLayoutGlyphsCache::self()->GetLayoutGlyphs(
+                        mpOutputDevice, aText, nPos, nLen);
+                    mpOutputDevice->DrawTextArray(aStartPoint, aText, aDXArray,
+                                                  rTextCandidate.getKashidaArray(), nPos, nLen,
+                                                  SalLayoutFlags::NONE, pGlyphs);
+                }
+                else
+                {
+                    mpOutputDevice->DrawText(aStartPoint, aText, nPos, nLen);
+                }
             }
 
             if (rTextCandidate.getFontAttribute().getRTL())
diff --git a/include/vcl/outdev.hxx b/include/vcl/outdev.hxx
index bdbb2ecd1847..15c6cd130f71 100644
--- a/include/vcl/outdev.hxx
+++ b/include/vcl/outdev.hxx
@@ -21,6 +21,7 @@
 
 #include <sal/config.h>
 
+#include <comphelper/flagguard.hxx>
 #include <tools/gen.hxx>
 #include <tools/ref.hxx>
 #include <tools/solar.h>
@@ -259,6 +260,8 @@ private:
     mutable bool                    mbRefPoint : 1;
     mutable bool                    mbEnableRTL : 1;
 
+    bool mbNoFontScaling = false; // Used only by D2DWriteTextOutRenderer
+
 protected:
     mutable std::shared_ptr<vcl::font::PhysicalFontCollection> mxFontCollection;
     mutable std::shared_ptr<ImplFontCache> mxFontCache;
@@ -341,6 +344,8 @@ public:
     /// request XSpriteCanvas render interface
     css::uno::Reference< css::rendering::XSpriteCanvas > GetSpriteCanvas() const;
 
+    auto ScopedNoFontScaling() { return comphelper::FlagRestorationGuard(mbNoFontScaling, true); }
+
 protected:
 
     /** Acquire a graphics device that the output device uses to draw on.
diff --git a/include/vcl/vcllayout.hxx b/include/vcl/vcllayout.hxx
index c946f6f67884..b37e8ff6e45b 100644
--- a/include/vcl/vcllayout.hxx
+++ b/include/vcl/vcllayout.hxx
@@ -22,6 +22,7 @@
 #include <basegfx/point/b2dpoint.hxx>
 #include <basegfx/polygon/b2dpolypolygon.hxx>
 #include <basegfx/range/b2drectangle.hxx>
+#include <comphelper/flagguard.hxx>
 #include <i18nlangtag/languagetag.hxx>
 #include <tools/gen.hxx>
 #include <tools/degree.hxx>
@@ -110,6 +111,9 @@ public:
 
     virtual SalLayoutGlyphs GetGlyphs() const;
 
+    auto ScopedFontScaling(bool v) { return comphelper::FlagRestorationGuard(mbScaleFont, v); }
+    bool ScaleFont() const { return mbScaleFont; }
+
 protected:
     // used by layout engines
     SalLayout();
@@ -118,6 +122,8 @@ private:
     SalLayout(const SalLayout&) = delete;
     SalLayout& operator=(const SalLayout&) = delete;
 
+    bool mbScaleFont = true; // Used only by D2DWriteTextOutRenderer
+
 protected:
     int             mnMinCharPos;
     int             mnEndCharPos;
diff --git a/vcl/source/outdev/text.cxx b/vcl/source/outdev/text.cxx
index b68602e9e90c..edd215943a3c 100644
--- a/vcl/source/outdev/text.cxx
+++ b/vcl/source/outdev/text.cxx
@@ -449,7 +449,7 @@ void OutputDevice::ImplDrawSpecialText( SalLayout& rSalLayout )
 
 void OutputDevice::ImplDrawText( SalLayout& rSalLayout )
 {
-
+    auto guard = rSalLayout.ScopedFontScaling(!mbNoFontScaling);
     if( mbInitClipRegion )
         InitClipRegion();
     if( mbOutputClipped )
diff --git a/vcl/win/gdi/DWriteTextRenderer.cxx b/vcl/win/gdi/DWriteTextRenderer.cxx
index ff39275b36b9..6a28cb4b4d98 100644
--- a/vcl/win/gdi/DWriteTextRenderer.cxx
+++ b/vcl/win/gdi/DWriteTextRenderer.cxx
@@ -332,12 +332,14 @@ WinFontTransformGuard::WinFontTransformGuard(ID2D1RenderTarget* pRenderTarget,
                                              bool bIsVertical)
     : mpRenderTarget(pRenderTarget)
 {
-    const float hscale = [&font = rLayout.GetFont()]
+    const float hscale = [&rLayout]
     {
-        const auto& rPattern = font.GetFontSelectPattern();
+        if (!rLayout.ScaleFont())
+            return 1.0;
+        const auto& rPattern = rLayout.GetFont().GetFontSelectPattern();
         if (!rPattern.mnHeight || !rPattern.mnWidth)
             return 1.0;
-        return rPattern.mnWidth * font.GetAverageWidthFactor() / rPattern.mnHeight;
+        return rPattern.mnWidth * rLayout.GetFont().GetAverageWidthFactor() / rPattern.mnHeight;
     }();
 
     Degree10 angle = rLayout.GetOrientation();