Related: tdf#94238 PPTX import: handle subset of radial gradient fill

Handle the case when the horizontal center is at 50%. Other cases are
still unhandled, those are more complex.

After fixing the style, center and border, the gradient fill looks
similar to how PowerPoint renders it.

Change-Id: I419da70482de37031aa2c7fc735692019d7665f5
Reviewed-on: https://gerrit.libreoffice.org/67168Reviewed-by: Miklos Vajna <vmiklos@collabora.com>
Tested-by: Jenkins

include/oox/drawingml/color.hxx

@@ -103,6 +103,9 @@ public:
     /** Translates between color transformation token names and the corresponding token */
     static sal_Int32    getColorTransformationToken( const OUString& sName );
 
+    /// Compares this color with rOther.
+    bool equals(const Color& rOther, const GraphicHelper& rGraphicHelper, ::Color nPhClr) const;
+
 private:
     /** Internal helper for getColor(). */
     void                setResolvedRgb( ::Color nRgb ) const;

oox/source/drawingml/color.cxx

@@ -431,6 +431,14 @@ sal_Int32 Color::getColorTransformationToken( const OUString& sName )
     return XML_TOKEN_INVALID;
 }
 
+bool Color::equals(const Color& rOther, const GraphicHelper& rGraphicHelper, ::Color nPhClr) const
+{
+    if (getColor(rGraphicHelper, nPhClr) != rOther.getColor(rGraphicHelper, nPhClr))
+        return false;
+
+    return getTransparency() == rOther.getTransparency();
+}
+
 void Color::clearTransparence()
 {
     mnAlpha = MAX_PERCENT;

oox/source/drawingml/fillproperties.cxx

@@ -154,6 +154,30 @@ const awt::Size lclGetOriginalSize( const GraphicHelper& rGraphicHelper, const R
     return aSizeHmm;
 }
 
+/**
+ * Looks for a last gradient transition and possibly sets a gradient border
+ * based on that.
+ */
+void extractGradientBorderFromStops(const GradientFillProperties& rGradientProps,
+                                    const GraphicHelper& rGraphicHelper, ::Color nPhClr,
+                                    awt::Gradient& rGradient)
+{
+    if (rGradientProps.maGradientStops.size() <= 1)
+        return;
+
+    auto it = rGradientProps.maGradientStops.rbegin();
+    double fLastPos = it->first;
+    Color aLastColor = it->second;
+    ++it;
+    double fLastButOnePos = it->first;
+    Color aLastButOneColor = it->second;
+    if (!aLastColor.equals(aLastButOneColor, rGraphicHelper, nPhClr))
+        return;
+
+    // Last transition has the same color, we can map that to a border.
+    rGradient.Border = rtl::math::round((fLastPos - fLastButOnePos) * 100);
+}
+
 } // namespace
 
 void GradientFillProperties::assignUsed( const GradientFillProperties& rSourceProps )
@@ -354,15 +378,28 @@ void FillProperties::pushToPropMap( ShapePropertyMap& rPropMap,
 
                     if( maGradientProps.moGradientPath.has() )
                     {
-                        aGradient.Style = (maGradientProps.moGradientPath.get() == XML_circle) ? awt::GradientStyle_ELLIPTICAL : awt::GradientStyle_RECT;
-                        // position of gradient center (limited to [30%;70%], otherwise gradient is too hidden)
+                        // position of gradient center (limited to [30%;100%], otherwise gradient is too hidden)
                         IntegerRectangle2D aFillToRect = maGradientProps.moFillToRect.get( IntegerRectangle2D( 0, 0, MAX_PERCENT, MAX_PERCENT ) );
                         sal_Int32 nCenterX = (MAX_PERCENT + aFillToRect.X1 - aFillToRect.X2) / 2;
-                        aGradient.XOffset = getLimitedValue< sal_Int16, sal_Int32 >( nCenterX / PER_PERCENT, 30, 70 );
+                        aGradient.XOffset = getLimitedValue<sal_Int16, sal_Int32>(
+                            nCenterX / PER_PERCENT, 30, 100);
+
+                        // Style should be radial at least when the horizontal center is at 50%.
+                        awt::GradientStyle eCircle = aGradient.XOffset == 50
+                                                         ? awt::GradientStyle_RADIAL
+                                                         : awt::GradientStyle_ELLIPTICAL;
+                        aGradient.Style = (maGradientProps.moGradientPath.get() == XML_circle)
+                                              ? eCircle
+                                              : awt::GradientStyle_RECT;
+
                         sal_Int32 nCenterY = (MAX_PERCENT + aFillToRect.Y1 - aFillToRect.Y2) / 2;
-                        aGradient.YOffset = getLimitedValue< sal_Int16, sal_Int32 >( nCenterY / PER_PERCENT, 30, 70 );
+                        aGradient.YOffset = getLimitedValue<sal_Int16, sal_Int32>(
+                            nCenterY / PER_PERCENT, 30, 100);
                         ::std::swap( aGradient.StartColor, aGradient.EndColor );
                         ::std::swap( nStartTrans, nEndTrans );
+
+                        extractGradientBorderFromStops(maGradientProps, rGraphicHelper, nPhClr,
+                                                       aGradient);
                     }
                     else if (!maGradientProps.maGradientStops.empty())
                     {
@@ -394,8 +431,7 @@ void FillProperties::pushToPropMap( ShapePropertyMap& rPropMap,
                             GradientFillProperties::GradientStopMap::const_iterator aItZ(std::prev(aGradientStops.end()));
                             while( bSymmetric && aItA->first < aItZ->first )
                             {
-                                if( aItA->second.getColor( rGraphicHelper, nPhClr ) != aItZ->second.getColor( rGraphicHelper, nPhClr ) ||
-                                    aItA->second.getTransparency() != aItZ->second.getTransparency() )
+                                if (!aItA->second.equals(aItZ->second, rGraphicHelper, nPhClr))
                                     bSymmetric = false;
                                 else
                                 {

sd/qa/unit/import-tests.cxx

@@ -190,6 +190,7 @@ public:
     void testTdf119015();
     void testTdf120028();
     void testTdf120028b();
+    void testTdf94238();
 
     CPPUNIT_TEST_SUITE(SdImportTest);
 
@@ -273,6 +274,7 @@ public:
     CPPUNIT_TEST(testTdf119015);
     CPPUNIT_TEST(testTdf120028);
     CPPUNIT_TEST(testTdf120028b);
+    CPPUNIT_TEST(testTdf94238);
 
     CPPUNIT_TEST_SUITE_END();
 };
@@ -2592,6 +2594,37 @@ void SdImportTest::testTdf120028b()
     xDocShRef->DoClose();
 }
 
+void SdImportTest::testTdf94238()
+{
+    // Assert how the gradient fill of the only shape in the document is
+    // imported.
+    ::sd::DrawDocShellRef xDocShRef
+        = loadURL(m_directories.getURLFromSrc("/sd/qa/unit/data/pptx/tdf94238.pptx"), PPTX);
+    uno::Reference<drawing::XDrawPagesSupplier> xDoc(xDocShRef->GetDoc()->getUnoModel(),
+                                                     uno::UNO_QUERY);
+    CPPUNIT_ASSERT(xDoc.is());
+
+    uno::Reference<drawing::XDrawPage> xPage(xDoc->getDrawPages()->getByIndex(0), uno::UNO_QUERY);
+    CPPUNIT_ASSERT(xPage.is());
+
+    uno::Reference<beans::XPropertySet> xShape(getShape(0, xPage));
+    CPPUNIT_ASSERT(xShape.is());
+
+    awt::Gradient aGradient;
+    CPPUNIT_ASSERT(xShape->getPropertyValue("FillGradient") >>= aGradient);
+
+    // Without the accompanying fix in place, this test would have failed with
+    // the following details:
+    // - aGradient.Style was awt::GradientStyle_ELLIPTICAL
+    // - aGradient.YOffset was 70
+    // - aGradient.Border was 0
+    CPPUNIT_ASSERT_EQUAL(awt::GradientStyle_RADIAL, aGradient.Style);
+    CPPUNIT_ASSERT_EQUAL(static_cast<sal_Int16>(100), aGradient.YOffset);
+    CPPUNIT_ASSERT_EQUAL(static_cast<sal_Int16>(39), aGradient.Border);
+
+    xDocShRef->DoClose();
+}
+
 CPPUNIT_TEST_SUITE_REGISTRATION(SdImportTest);
 
 CPPUNIT_PLUGIN_IMPLEMENT();