tdf#53004 tdf#142495 WMF EMF Fix displaying Text with OPAQUE and CLIPPED

With OPAQUE option enabled, the rectangle need to be drawn,
before drawing text.

With CLIPPED option enabled, the text needs to be drawn
only inside rectangle.

In previous implementation, the rectangle read was skipped and
it was not drawn (for OPAQUE).

For CLIPPED the rectangle was read but Clip was not applied
to text drawing

This commit fix that issues, and allow to draw rectangle correctly,
with BGColor (background color), and add support for Text Clipping
according to [MS-WMF] and [MS-EMF] specification.
The fix applied to EMR_EXTTEXTOUTW, EMR_EXTTEXTOUTA and EXTTEXTOUT records

Change-Id: I0f6248bb9465e6d5f797cddb53f058afb0815a2d
Reviewed-on: https://gerrit.libreoffice.org/c/core/+/116072
Tested-by: Jenkins
Reviewed-by: Bartosz Kosiorek <gang65@poczta.onet.pl>

3 files changed, 62 insertions, 33 deletions

diff --git a/emfio/source/reader/emfreader.cxx b/emfio/source/reader/emfreader.cxx
index 9a8784c7e631..e6a758175fb5 100644
--- a/emfio/source/reader/emfreader.cxx
+++ b/emfio/source/reader/emfreader.cxx
@@ -1795,14 +1795,18 @@ namespace emfio
                         [[fallthrough]];
                     case EMR_EXTTEXTOUTW :
                     {
-                        sal_Int32   nLeft, nTop, nRight, nBottom, ptlReferenceX, ptlReferenceY, nGfxMode, nXScale, nYScale;
-                        sal_uInt32  nOffString, nOptions, offDx;
-                        sal_Int32   nLen;
+                        sal_Int32   nLeft, nTop, nRight, nBottom;
+                        sal_uInt32  nGfxMode;
+                        float       nXScale, nYScale;
+                        sal_Int32   ptlReferenceX, ptlReferenceY;
+                        sal_uInt32  nLen, nOffString, nOptions, offDx;
+                        sal_Int32   nLeftRect, nTopRect, nRightRect, nBottomRect;
 
                         nCurPos = mpInputStream->Tell() - 8;
 
-                        mpInputStream->ReadInt32( nLeft ).ReadInt32( nTop ).ReadInt32( nRight ).ReadInt32( nBottom ).ReadInt32( nGfxMode ).ReadInt32( nXScale ).ReadInt32( nYScale )
-                           .ReadInt32( ptlReferenceX ).ReadInt32( ptlReferenceY ).ReadInt32( nLen ).ReadUInt32( nOffString ).ReadUInt32( nOptions );
+                        mpInputStream->ReadInt32( nLeft ).ReadInt32( nTop ).ReadInt32( nRight ).ReadInt32( nBottom )
+                           .ReadUInt32( nGfxMode ).ReadFloat( nXScale ).ReadFloat( nYScale )
+                           .ReadInt32( ptlReferenceX ).ReadInt32( ptlReferenceY ).ReadUInt32( nLen ).ReadUInt32( nOffString ).ReadUInt32( nOptions );
 
                         SAL_INFO("emfio", "\t\tBounds: " << nLeft << ", " << nTop << ", " << nRight << ", " << nBottom);
                         SAL_INFO("emfio", "\t\tiGraphicsMode: 0x" << std::hex << nGfxMode << std::dec);
@@ -1810,7 +1814,13 @@ namespace emfio
                         SAL_INFO("emfio", "\t\teyScale: " << nYScale);
                         SAL_INFO("emfio", "\t\tReference: (" << ptlReferenceX << ", " << ptlReferenceY << ")");
 
-                        mpInputStream->SeekRel( 0x10 );
+                        mpInputStream->ReadInt32( nLeftRect ).ReadInt32( nTopRect ).ReadInt32( nRightRect ).ReadInt32( nBottomRect );
+                        const tools::Rectangle aRect( nLeftRect, nTopRect, nRightRect, nBottomRect );
+                        BkMode mnBkModeBackup = mnBkMode;
+                        if ( nOptions & ETO_NO_RECT ) // Don't draw the background rectangle
+                            mnBkMode = BkMode::Transparent;
+                        if ( nOptions & ETO_OPAQUE )
+                            DrawRectWithBGColor( aRect );
                         mpInputStream->ReadUInt32( offDx );
 
                         ComplexTextLayoutFlags nTextLayoutMode = ComplexTextLayoutFlags::Default;
@@ -1820,15 +1830,14 @@ namespace emfio
                         SAL_WARN_IF( ( nOptions & ( ETO_PDY | ETO_GLYPH_INDEX ) ) != 0, "emfio", "SJ: ETO_PDY || ETO_GLYPH_INDEX in EMF" );
 
                         Point aPos( ptlReferenceX, ptlReferenceY );
-                        bool bLenSane = nLen > 0 && nLen < static_cast<sal_Int32>( SAL_MAX_UINT32 / sizeof(sal_Int32) );
                         bool bOffStringSane = nOffString <= mnEndPos - nCurPos;
-                        if (bLenSane && bOffStringSane)
+                        if ( bOffStringSane )
                         {
                             mpInputStream->Seek( nCurPos + nOffString );
                             OUString aText;
                             if ( bFlag )
                             {
-                                if ( nLen <= static_cast<sal_Int32>( mnEndPos - mpInputStream->Tell() ) )
+                                if ( nLen <= ( mnEndPos - mpInputStream->Tell() ) )
                                 {
                                     std::unique_ptr<char[]> pBuf(new char[ nLen ]);
                                     mpInputStream->ReadBytes(pBuf.get(), nLen);
@@ -1862,7 +1871,7 @@ namespace emfio
                                 for (sal_Int32 i = 0; i < aText.getLength(); ++i)
                                 {
                                     sal_Int32 nDxCount = 1;
-                                    if (aText.getLength() != nLen)
+                                    if (aText.getLength() != static_cast<sal_Int32>( nLen ) )
                                     {
                                         sal_Unicode cUniChar = aText[i];
                                         OString aTmp(&cUniChar, 1, GetCharSet());
@@ -1894,7 +1903,15 @@ namespace emfio
                                     }
                                 }
                             }
+                            if ( nOptions & ETO_CLIPPED )
+                            {
+                                Push(); // Save the current clip. It will be restored after text drawing
+                                IntersectClipRect( aRect );
+                            }
                             DrawText(aPos, aText, pDXAry.get(), pDYAry.get(), mbRecordPath, nGfxMode);
+                            if ( nOptions & ETO_CLIPPED )
+                                Pop();
+                            mnBkMode = mnBkModeBackup;
                         }
                     }
                     break;
diff --git a/emfio/source/reader/mtftools.cxx b/emfio/source/reader/mtftools.cxx
index d68e36e361ef..6bf0d98a3e76 100644
--- a/emfio/source/reader/mtftools.cxx
+++ b/emfio/source/reader/mtftools.cxx
@@ -1051,14 +1051,8 @@ namespace emfio
         {
             return; // empty rectangles cause trouble
         }
-        Point aPoints[] { Point(rRect.Left(), rRect.Top()),
-                          Point(rRect.Right(), rRect.Top()),
-                          Point(rRect.Right(), rRect.Bottom()),
-                          Point(rRect.Left(), rRect.Bottom()) };
-        tools::Polygon aPoly(4, aPoints);
-        aPoly = ImplMap( aPoly );
-        aPoly.Optimize( PolyOptimizeFlags::CLOSE );
-        tools::PolyPolygon aPolyPolyRect( aPoly );
+        tools::Polygon aPoly( rRect );
+        const tools::PolyPolygon aPolyPolyRect( ImplMap( aPoly ) );
         maClipPath.intersectClip( aPolyPolyRect.getB2DPolyPolygon() );
     }
 
@@ -1067,15 +1061,8 @@ namespace emfio
         if (utl::ConfigManager::IsFuzzing())
             return;
         mbClipNeedsUpdate=true;
-
-        Point aPoints[] { Point(rRect.Left(), rRect.Top()),
-                          Point(rRect.Right(), rRect.Top()),
-                          Point(rRect.Right(), rRect.Bottom()),
-                          Point(rRect.Left(), rRect.Bottom()) };
-        tools::Polygon aPoly(4, aPoints);
-        aPoly = ImplMap( aPoly );
-        aPoly.Optimize( PolyOptimizeFlags::CLOSE );
-        tools::PolyPolygon aPolyPolyRect( aPoly );
+        tools::Polygon aPoly( rRect );
+        const tools::PolyPolygon aPolyPolyRect( ImplMap( aPoly ) );
         maClipPath.excludeClip( aPolyPolyRect.getB2DPolyPolygon() );
     }
 
@@ -1390,6 +1377,20 @@ namespace emfio
         maActPos = aDest;
     }
 
+    void MtfTools::DrawRectWithBGColor(const tools::Rectangle& rRect)
+    {
+        WinMtfFillStyle aFillStyleBackup = maFillStyle;
+        bool            aTransparentBackup = maLineStyle.bTransparent;
+
+        const tools::Polygon aPoly( rRect );
+        maLineStyle.bTransparent = true;
+        maFillStyle = maBkColor;
+        ImplSetNonPersistentLineColorTransparenz();
+        DrawPolygon(aPoly, false);
+        maFillStyle = aFillStyleBackup;
+        maLineStyle.bTransparent = aTransparentBackup;
+    }
+
     void MtfTools::DrawRect( const tools::Rectangle& rRect, bool bEdge )
     {
         UpdateClipRegion();
diff --git a/emfio/source/reader/wmfreader.cxx b/emfio/source/reader/wmfreader.cxx
index 2f0aafabfaa9..f14949135ad4 100644
--- a/emfio/source/reader/wmfreader.cxx
+++ b/emfio/source/reader/wmfreader.cxx
@@ -666,8 +666,9 @@ namespace emfio
                 Point aPosition = ReadYX();
                 sal_uInt16 nLen = 0, nOptions = 0;
                 mpInputStream->ReadUInt16( nLen ).ReadUInt16( nOptions );
-
-                if (nOptions & ETO_CLIPPED)
+                SAL_INFO( "emfio", "\t\t\t Pos: " << aPosition.getX() << ":" << aPosition.getY() << " String Length: " << nLen << " Options: " << nOptions );
+                tools::Rectangle aRect;
+                if ( ( nOptions & ETO_CLIPPED ) || ( nOptions & ETO_OPAQUE ) )
                 {
                     nNonStringLen += 2 * sizeof(sal_uInt16);
 
@@ -676,10 +677,12 @@ namespace emfio
                         SAL_WARN("emfio", "W_META_TEXTOUT too short");
                         break;
                     }
-
-                    ReadPoint();
-                    ReadPoint();
-                    SAL_WARN("emfio", "clipping unsupported");
+                    const Point aTopLeft = ReadPoint();
+                    const Point aBottomRight = ReadPoint();
+                    aRect = tools::Rectangle( aTopLeft, aBottomRight );
+                    if ( nOptions & ETO_OPAQUE )
+                        DrawRectWithBGColor( aRect );
+                    SAL_INFO( "emfio", "\t\t\t Rectangle : " << aTopLeft.getX() << ":" << aTopLeft.getY() << ", " << aBottomRight.getX() << ":" << aBottomRight.getY() );
                 }
 
                 ComplexTextLayoutFlags nTextLayoutMode = ComplexTextLayoutFlags::Default;
@@ -709,6 +712,12 @@ namespace emfio
                                                                                        // dxAry will not fit
                     if ( nNewTextLen )
                     {
+                        if ( nOptions & ETO_CLIPPED )
+                        {
+                            Push(); // Save the current clip. It will be restored after text drawing
+                            IntersectClipRect( aRect );
+                        }
+                        SAL_INFO( "emfio", "\t\t\t Text : " << aText );
                         std::unique_ptr<tools::Long[]> pDXAry, pDYAry;
                         auto nDxArySize =  nMaxStreamPos - mpInputStream->Tell();
                         auto nDxAryEntries = nDxArySize >> 1;
@@ -768,6 +777,8 @@ namespace emfio
                             DrawText( aPosition, aText, pDXAry.get(), pDYAry.get() );
                         else
                             DrawText( aPosition, aText );
+                        if ( nOptions & ETO_CLIPPED )
+                            Pop();
                     }
                 }
             }