svx UnoGraphicExporter: allow a custom AA just for that particular export

This has an effect for text only since the cairo text renderer no longer
ignores the "disable AA" requests.

To use it, instantiate com.sun.star.drawing.GraphicExportFilter, call
its filter() method with an argument that has a FilterData, which has an
AntiAliasing sub-key with a boolean value.

Change-Id: I4f51bc685a97141eb0fdeae5e4afed26787b1fb8
Reviewed-on: https://gerrit.libreoffice.org/58194Reviewed-by: Miklos Vajna <vmiklos@collabora.co.uk>
Tested-by: Jenkins

svx/source/unodraw/UnoGraphicExporter.cxx

@@ -108,6 +108,8 @@ namespace {
         Fraction    maScaleX;
         Fraction    maScaleY;
 
+        TriState meAntiAliasing = TRISTATE_INDET;
+
         explicit ExportSettings(const SdrModel* pSdrModel);
     };
 
@@ -584,6 +586,12 @@ void GraphicExporter::ParseSettings( const Sequence< PropertyValue >& aDescripto
                     if( pDataValues->Value >>= nVal )
                         rSettings.maScaleY = Fraction( rSettings.maScaleY.GetNumerator(), nVal );
                 }
+                else if (pDataValues->Name == "AntiAliasing")
+                {
+                    bool bAntiAliasing;
+                    if (pDataValues->Value >>= bAntiAliasing)
+                        rSettings.meAntiAliasing = bAntiAliasing ? TRISTATE_TRUE : TRISTATE_FALSE;
+                }
 
                 pDataValues++;
             }
@@ -1020,7 +1028,16 @@ sal_Bool SAL_CALL GraphicExporter::filter( const Sequence< PropertyValue >& aDes
 
     ErrCode nStatus = ERRCODE_NONE;
     if (!maGraphic)
+    {
+        SvtOptionsDrawinglayer aOptions;
+        bool bAntiAliasing = aOptions.IsAntiAliasing();
+        if (aSettings.meAntiAliasing != TRISTATE_INDET)
+            // This is safe to do globally as we own the solar mutex.
+            aOptions.SetAntiAliasing(aSettings.meAntiAliasing == TRISTATE_TRUE);
         nStatus = GetGraphic( aSettings, aGraphic, bVectorType ) ? ERRCODE_NONE : ERRCODE_GRFILTER_FILTERERROR;
+        if (aSettings.meAntiAliasing != TRISTATE_INDET)
+            aOptions.SetAntiAliasing(bAntiAliasing);
+    }
 
     if( nStatus == ERRCODE_NONE )
     {