MCGR: consolidations/cleanups for changes so far

Change-Id: I85cf40e4803b0485bb40349d8e81adc8123666c4
Reviewed-on: https://gerrit.libreoffice.org/c/core/+/151706
Tested-by: Jenkins
Reviewed-by: Armin Le Grand <Armin.Le.Grand@me.com>

7 files changed, 170 insertions, 116 deletions

diff --git a/drawinglayer/inc/texture/texture.hxx b/drawinglayer/inc/texture/texture.hxx
index 01d3ec5c64c5..5128a30cf2a8 100644
--- a/drawinglayer/inc/texture/texture.hxx
+++ b/drawinglayer/inc/texture/texture.hxx
@@ -49,21 +49,18 @@ namespace drawinglayer::texture
             basegfx::ODFGradientInfo            maGradientInfo;
             basegfx::B2DRange                   maDefinitionRange;
             sal_uInt32                          mnRequestedSteps;
-            basegfx::ColorStops                 mnColorStops;
+            basegfx::BColorStops                mnColorStops;
             double                              mfBorder;
 
             // provide a single buffer entry used for gradient texture
             // mapping, see ::modifyBColor implementations
-            mutable basegfx::ColorStopRange     maLastColorStopRange;
-
-            // check if we need last-ColorStop-correction
-            bool checkPenultimate();
+            mutable basegfx::BColorStops::BColorStopRange     maLastColorStopRange;
 
         public:
             GeoTexSvxGradient(
                 const basegfx::B2DRange& rDefinitionRange,
                 sal_uInt32 nRequestedSteps,
-                const basegfx::ColorStops& rColorStops,
+                const basegfx::BColorStops& rColorStops,
                 double fBorder);
             virtual ~GeoTexSvxGradient() override;
 
@@ -86,7 +83,7 @@ namespace drawinglayer::texture
                 const basegfx::B2DRange& rDefinitionRange,
                 const basegfx::B2DRange& rOutputRange,
                 sal_uInt32 nRequestedSteps,
-                const basegfx::ColorStops& rColorStops,
+                const basegfx::BColorStops& rColorStops,
                 double fBorder,
                 double fAngle);
             virtual ~GeoTexSvxGradientLinear() override;
@@ -106,7 +103,7 @@ namespace drawinglayer::texture
                 const basegfx::B2DRange& rDefinitionRange,
                 const basegfx::B2DRange& rOutputRange,
                 sal_uInt32 nRequestedSteps,
-                const basegfx::ColorStops& rColorStops,
+                const basegfx::BColorStops& rColorStops,
                 double fBorder,
                 double fAngle);
             virtual ~GeoTexSvxGradientAxial() override;
@@ -122,7 +119,7 @@ namespace drawinglayer::texture
             GeoTexSvxGradientRadial(
                 const basegfx::B2DRange& rDefinitionRange,
                 sal_uInt32 nRequestedSteps,
-                const basegfx::ColorStops& rColorStops,
+                const basegfx::BColorStops& rColorStops,
                 double fBorder,
                 double fOffsetX,
                 double fOffsetY);
@@ -139,7 +136,7 @@ namespace drawinglayer::texture
             GeoTexSvxGradientElliptical(
                 const basegfx::B2DRange& rDefinitionRange,
                 sal_uInt32 nRequestedSteps,
-                const basegfx::ColorStops& rColorStops,
+                const basegfx::BColorStops& rColorStops,
                 double fBorder,
                 double fOffsetX,
                 double fOffsetY,
@@ -157,7 +154,7 @@ namespace drawinglayer::texture
             GeoTexSvxGradientSquare(
                 const basegfx::B2DRange& rDefinitionRange,
                 sal_uInt32 nRequestedSteps,
-                const basegfx::ColorStops& rColorStops,
+                const basegfx::BColorStops& rColorStops,
                 double fBorder,
                 double fOffsetX,
                 double fOffsetY,
@@ -175,7 +172,7 @@ namespace drawinglayer::texture
             GeoTexSvxGradientRect(
                 const basegfx::B2DRange& rDefinitionRange,
                 sal_uInt32 nRequestedSteps,
-                const basegfx::ColorStops& rColorStops,
+                const basegfx::BColorStops& rColorStops,
                 double fBorder,
                 double fOffsetX,
                 double fOffsetY,
diff --git a/drawinglayer/qa/unit/vclpixelprocessor2d.cxx b/drawinglayer/qa/unit/vclpixelprocessor2d.cxx
index 6ccf1e7c55ab..7f59e7e3edd0 100644
--- a/drawinglayer/qa/unit/vclpixelprocessor2d.cxx
+++ b/drawinglayer/qa/unit/vclpixelprocessor2d.cxx
@@ -16,8 +16,10 @@
 #include <tools/stream.hxx>
 #include <drawinglayer/geometry/viewinformation2d.hxx>
 #include <drawinglayer/primitive2d/fillgradientprimitive2d.hxx>
+#include <drawinglayer/primitive2d/maskprimitive2d.hxx>
 #include <drawinglayer/processor2d/baseprocessor2d.hxx>
 #include <drawinglayer/processor2d/processor2dtools.hxx>
+#include <basegfx/polygon/b2dpolygontools.hxx>
 #include <basegfx/utils/gradienttools.hxx>
 
 using namespace drawinglayer;
@@ -58,16 +60,59 @@ public:
             processor2d::createProcessor2DFromOutputDevice(*device, view));
         CPPUNIT_ASSERT(processor);
 
+        // I stumbled over this when hunting another problem, but I have to correct
+        // this: This test does test something that is not supported. It seems to be
+        // based on the *misunderstanding* that in the version of the constructor of
+        // FillGradientPrimitive2D (and similar others) with two ranges the 2nd
+        // B2DRange parameter 'OutputRange' is a 'clipping' parameter. This is *not*
+        // the case --- it is in fact the *contrary*, it is there to *extend* the
+        // usual definition/paintRange of a gradient:
+        // It was originally needed to correctly display TextFrames (TF) in Writer: If you
+        // have a TF in SW filled with a gradient and that TF has sub-frames, it inhertits
+        // the gradient fill. Since you can freely move those sub-TFs even outside the
+        // parent TF there has to be a way to not only paint gradients in ther definition
+        // range (classical, all DrawObjects do that), but extended from that. This is
+        // needed e.g. for linerar gradients, but - dependent of e.g. the center settings -
+        // also for all other ones, all can have geometry 'outside' the DefinitionRange.
+        // This is now also used in various other locations which is proof that this is
+        // useful and needed. It is possible to see that basic history/reason for this
+        // parameter by following the git history and why and under which circumstances
+        // that parameter was originally added. Other hints are: It is *not* named
+        // 'ClipRange'. Using a B2DRange to define a ClipRange topology would be bad due
+        // to not being transformable, a PolyPolygon would be used in that case. Using as
+        // clipping mechanism would offer a 2nd pinciple to add clipping for primitives
+        // besides MaskPrimitive2D - always bad style in a sub-system. A quick look
+        // on it's usages gives hints, too.
+        // This means that when defining a outputRange tat resides completely *inside*
+        // the definitionRange *no change* at all is done by definition since this does
+        // not *extend* the target area of the gradient paint region at all. If an
+        // implementation does clip and limit output to 'outputRange' that should do no
+        // harm, but is not the expected/reliable way to paint primitives clipped.
+        // That's why all DrawObjects with gradient fill (and other fills do the same)
+        // embed the fill that is defined for a range (usually the BoundRange of a
+        // PolyPolygon) in a MaskPrimitive2D defined by the outline PolyPolygon of the
+        // shape. Nothing speaks against renderers detecting that combination and do
+        // something optimized if they want to, especially SDPRs, but this is not
+        // required. The standard embedded clipping of the mplementations of the
+        // MaskPrimitive2D do the right thing.
+        // This test intends to paint the lower part of a gradient, so define the
+        // gradient for the full target range and embed it to a MaskPrimitive2D
+        // defining the lower part of that area to do that.
+
         basegfx::B2DRange definitionRange(0, 0, 100, 200);
         basegfx::B2DRange outputRange(0, 100, 100, 200); // Paint only lower half of the gradient.
-        attribute::FillGradientAttribute attributes(
-            css::awt::GradientStyle_LINEAR, 0, 0, 0, 0,
-            basegfx::utils::createColorStopsFromStartEndColor(COL_WHITE.getBColor(),
-                                                              COL_BLACK.getBColor()));
-        rtl::Reference<primitive2d::FillGradientPrimitive2D> gradientPrimitive(
-            new primitive2d::FillGradientPrimitive2D(outputRange, definitionRange, attributes));
-        primitive2d::Primitive2DContainer primitives;
-        primitives.push_back(primitive2d::Primitive2DReference(gradientPrimitive));
+
+        const primitive2d::Primitive2DContainer primitives{
+            rtl::Reference<primitive2d::MaskPrimitive2D>(new primitive2d::MaskPrimitive2D(
+                basegfx::B2DPolyPolygon(basegfx::utils::createPolygonFromRect(outputRange)),
+                primitive2d::Primitive2DContainer{
+                    rtl::Reference<primitive2d::FillGradientPrimitive2D>(
+                        new primitive2d::FillGradientPrimitive2D(
+                            definitionRange, attribute::FillGradientAttribute(
+                                                 css::awt::GradientStyle_LINEAR, 0, 0, 0, 0,
+                                                 basegfx::BColorStops(COL_WHITE.getBColor(),
+                                                                      COL_BLACK.getBColor())))) }))
+        };
         processor->process(primitives);
 
         exportDevice("test-tdf139000.png", device);
diff --git a/drawinglayer/source/attribute/fillgradientattribute.cxx b/drawinglayer/source/attribute/fillgradientattribute.cxx
index 0233195113af..e02fdd4a5dad 100644
--- a/drawinglayer/source/attribute/fillgradientattribute.cxx
+++ b/drawinglayer/source/attribute/fillgradientattribute.cxx
@@ -30,7 +30,7 @@ namespace drawinglayer::attribute
             double                                  mfOffsetX;
             double                                  mfOffsetY;
             double                                  mfAngle;
-            basegfx::ColorStops                     maColorStops;
+            basegfx::BColorStops                    maColorStops;
             css::awt::GradientStyle                 meStyle;
             sal_uInt16                              mnSteps;
 
@@ -40,7 +40,7 @@ namespace drawinglayer::attribute
                 double fOffsetX,
                 double fOffsetY,
                 double fAngle,
-                const basegfx::ColorStops& rColorStops,
+                const basegfx::BColorStops& rColorStops,
                 sal_uInt16 nSteps)
             :   mfBorder(fBorder),
                 mfOffsetX(fOffsetX),
@@ -57,7 +57,7 @@ namespace drawinglayer::attribute
                 // This is what the usages of this in primitives need.
                 // Since FillGradientAttribute is read-only doing this
                 // once here in the constructor is sufficient
-                basegfx::utils::sortAndCorrectColorStops(maColorStops);
+                maColorStops.sortAndCorrect();
 
                 // sortAndCorrectColorStops is rigid and can return
                 // an empty result. To keep things simple, add a single
@@ -87,18 +87,9 @@ namespace drawinglayer::attribute
             double getOffsetX() const { return mfOffsetX; }
             double getOffsetY() const { return mfOffsetY; }
             double getAngle() const { return mfAngle; }
-            const basegfx::ColorStops& getColorStops() const { return maColorStops; }
+            const basegfx::BColorStops& getColorStops() const { return maColorStops; }
             sal_uInt16 getSteps() const { return mnSteps; }
 
-            bool hasSingleColor() const
-            {
-                // No entry (should not happen, see comments for startColor above)
-                // or single entry -> no gradient.
-                // No need to check for all-the-same color since this is checked/done
-                // in the constructor already, see there
-                return maColorStops.size() < 2;
-            }
-
             bool operator==(const ImpFillGradientAttribute& rCandidate) const
             {
                 return (getStyle() == rCandidate.getStyle()
@@ -126,7 +117,7 @@ namespace drawinglayer::attribute
             double fOffsetX,
             double fOffsetY,
             double fAngle,
-            const basegfx::ColorStops& rColorStops,
+            const basegfx::BColorStops& rColorStops,
             sal_uInt16 nSteps)
         :   mpFillGradientAttribute(ImpFillGradientAttribute(
                 eStyle, fBorder, fOffsetX, fOffsetY, fAngle, rColorStops, nSteps))
@@ -149,11 +140,6 @@ namespace drawinglayer::attribute
             return mpFillGradientAttribute.same_object(theGlobalDefault());
         }
 
-        bool FillGradientAttribute::hasSingleColor() const
-        {
-            return mpFillGradientAttribute->hasSingleColor();
-        }
-
         // MCGR: Check if rendering cannot be handled by old vcl stuff
         bool FillGradientAttribute::cannotBeHandledByVCL() const
         {
@@ -202,7 +188,7 @@ namespace drawinglayer::attribute
             return rCandidate.mpFillGradientAttribute == mpFillGradientAttribute;
         }
 
-        const basegfx::ColorStops& FillGradientAttribute::getColorStops() const
+        const basegfx::BColorStops& FillGradientAttribute::getColorStops() const
         {
             return mpFillGradientAttribute->getColorStops();
         }
diff --git a/drawinglayer/source/primitive3d/textureprimitive3d.cxx b/drawinglayer/source/primitive3d/textureprimitive3d.cxx
index ebae584e9dbf..ceeca0489487 100644
--- a/drawinglayer/source/primitive3d/textureprimitive3d.cxx
+++ b/drawinglayer/source/primitive3d/textureprimitive3d.cxx
@@ -95,9 +95,9 @@ namespace drawinglayer::primitive3d
                 const basegfx::BColor aGray(getTransparence(), getTransparence(), getTransparence());
 
                 // create ColorStops with StartColor == EndColor == aGray
-                const basegfx::ColorStops aColorStops {
-                    basegfx::ColorStop(0.0, aGray),
-                    basegfx::ColorStop(1.0, aGray) };
+                const basegfx::BColorStops aColorStops {
+                    basegfx::BColorStop(0.0, aGray),
+                    basegfx::BColorStop(1.0, aGray) };
 
                 const attribute::FillGradientAttribute aFillGradient(css::awt::GradientStyle_LINEAR, 0.0, 0.0, 0.0, 0.0, aColorStops);
                 const Primitive3DReference xRef(new TransparenceTexturePrimitive3D(aFillGradient, getChildren(), getTextureSize()));
diff --git a/drawinglayer/source/processor3d/defaultprocessor3d.cxx b/drawinglayer/source/processor3d/defaultprocessor3d.cxx
index 20d81871dbd7..0d07b0a5c343 100644
--- a/drawinglayer/source/processor3d/defaultprocessor3d.cxx
+++ b/drawinglayer/source/processor3d/defaultprocessor3d.cxx
@@ -61,8 +61,9 @@ namespace drawinglayer::processor3d
             const basegfx::B2DRange aOutlineRange(0.0, 0.0, rPrimitive.getTextureSize().getX(), rPrimitive.getTextureSize().getY());
             const css::awt::GradientStyle aGradientStyle(rFillGradient.getStyle());
             std::shared_ptr< texture::GeoTexSvx > pNewTex;
+            basegfx::BColor aSingleColor;
 
-            if(!rFillGradient.hasSingleColor())
+            if (!rFillGradient.getColorStops().isSingleColor(aSingleColor))
             {
                 switch(aGradientStyle)
                 {
@@ -147,8 +148,7 @@ namespace drawinglayer::processor3d
             else
             {
                 // only one color, so no real gradient -> use simple texture
-                const basegfx::BColor aStart(rFillGradient.getColorStops().front().getStopColor());
-                pNewTex = std::make_shared<texture::GeoTexSvxMono>(aStart, 1.0 - aStart.luminance());
+                pNewTex = std::make_shared<texture::GeoTexSvxMono>(aSingleColor, 1.0 - aSingleColor.luminance());
                 mbSimpleTextureActive = true;
             }
 
diff --git a/drawinglayer/source/texture/texture.cxx b/drawinglayer/source/texture/texture.cxx
index eb9df6469225..5176838d610e 100644
--- a/drawinglayer/source/texture/texture.cxx
+++ b/drawinglayer/source/texture/texture.cxx
@@ -73,7 +73,7 @@ namespace drawinglayer::texture
         GeoTexSvxGradient::GeoTexSvxGradient(
             const basegfx::B2DRange& rDefinitionRange,
             sal_uInt32 nRequestedSteps,
-            const basegfx::ColorStops& rColorStops,
+            const basegfx::BColorStops& rColorStops,
             double fBorder)
         : maDefinitionRange(rDefinitionRange)
         , mnRequestedSteps(nRequestedSteps)
@@ -99,47 +99,11 @@ namespace drawinglayer::texture
                 && mfBorder == pCompare->mfBorder);
         }
 
-        bool GeoTexSvxGradient::checkPenultimate()
-        {
-            // not needed when no ColorStops
-            if (mnColorStops.empty())
-                return false;
-
-            // not needed when last ColorStop at the end or outside
-            if (basegfx::fTools::moreOrEqual(mnColorStops.back().getStopOffset(), 1.0))
-                return false;
-
-            // get penultimate entry
-            const auto penultimate(mnColorStops.rbegin() + 1);
-
-            // if there is none, we need no correction and are done
-            if (penultimate == mnColorStops.rend())
-                return false;
-
-            // not needed when the last two ColorStops have different offset, then
-            // a visible range will be processed already
-            if (!basegfx::fTools::equal(mnColorStops.back().getStopOffset(), penultimate->getStopOffset()))
-                return false;
-
-            // not needed when the last two ColorStops have the same Color, then the
-            // range before solves the problem
-            if (mnColorStops.back().getStopColor() == penultimate->getStopColor())
-                return false;
-
-            // Here we need to temporarily add a ColorStop entry with the
-            // same color as the last entry to correctly 'close' the
-            // created gradient geometry.
-            // The simplest way is to temporarily add an entry to the local
-            // ColorStops for this at 1.0 (using same color)
-            mnColorStops.emplace_back(1.0, mnColorStops.back().getStopColor());
-            return true;
-        }
-
         GeoTexSvxGradientLinear::GeoTexSvxGradientLinear(
             const basegfx::B2DRange& rDefinitionRange,
             const basegfx::B2DRange& rOutputRange,
             sal_uInt32 nRequestedSteps,
-            const basegfx::ColorStops& rColorStops,
+            const basegfx::BColorStops& rColorStops,
             double fBorder,
             double fAngle)
         : GeoTexSvxGradient(rDefinitionRange, nRequestedSteps, rColorStops, fBorder)
@@ -180,7 +144,17 @@ namespace drawinglayer::texture
                 return;
 
             // check if we need last-ColorStop-correction
-            const bool bPenultimateUsed(checkPenultimate());
+            const bool bPenultimateUsed(mnColorStops.checkPenultimate());
+
+            if (bPenultimateUsed)
+            {
+                // Here we need to temporarily add a ColorStop entry with the
+                // same color as the last entry to correctly 'close' the
+                // created gradient geometry.
+                // The simplest way is to temporarily add an entry to the local
+                // ColorStops for this at 1.0 (using same color)
+                mnColorStops.emplace_back(1.0, mnColorStops.back().getStopColor());
+            }
 
             // prepare unit range transform
             basegfx::B2DHomMatrix aPattern;
@@ -200,7 +174,7 @@ namespace drawinglayer::texture
                 const double fOffsetStart(cs_l->getStopOffset());
                 const double fOffsetEnd(cs_r->getStopOffset());
 
-                // same offset, empty ColorStopRange, continue with next step
+                // same offset, empty BColorStopRange, continue with next step
                 if (basegfx::fTools::equal(fOffsetStart, fOffsetEnd))
                     continue;
 
@@ -249,7 +223,10 @@ namespace drawinglayer::texture
             }
 
             if (bPenultimateUsed)
+            {
+                // correct temporary change
                 mnColorStops.pop_back();
+            }
         }
 
         void GeoTexSvxGradientLinear::modifyBColor(const basegfx::B2DPoint& rUV, basegfx::BColor& rBColor, double& /*rfOpacity*/) const
@@ -267,14 +244,14 @@ namespace drawinglayer::texture
 
             // texture-back-transform X/Y -> t [0.0..1.0] and determine color
             const double fScaler(basegfx::utils::getLinearGradientAlpha(rUV, maGradientInfo));
-            rBColor = basegfx::utils::modifyBColor(mnColorStops, fScaler, mnRequestedSteps, maLastColorStopRange);
+            rBColor = mnColorStops.getInterpolatedBColor(fScaler, mnRequestedSteps, maLastColorStopRange);
         }
 
         GeoTexSvxGradientAxial::GeoTexSvxGradientAxial(
             const basegfx::B2DRange& rDefinitionRange,
             const basegfx::B2DRange& rOutputRange,
             sal_uInt32 nRequestedSteps,
-            const basegfx::ColorStops& rColorStops,
+            const basegfx::BColorStops& rColorStops,
             double fBorder,
             double fAngle)
         : GeoTexSvxGradient(rDefinitionRange, nRequestedSteps, rColorStops, fBorder)
@@ -285,7 +262,7 @@ namespace drawinglayer::texture
             // with the other gradients. Either stay 'thinking reverse' for the
             // rest of time or adapt it here and go in same order as the other five,
             // so unifications/tooling will be possible
-            basegfx::utils::reverseColorStops(mnColorStops);
+            mnColorStops.reverseColorStops();
 
             maGradientInfo = basegfx::utils::createAxialODFGradientInfo(
                 rDefinitionRange,
@@ -319,7 +296,13 @@ namespace drawinglayer::texture
                 return;
 
             // check if we need last-ColorStop-correction
-            const bool bPenultimateUsed(checkPenultimate());
+            const bool bPenultimateUsed(mnColorStops.checkPenultimate());
+
+            if (bPenultimateUsed)
+            {
+                // temporarily add a ColorStop entry
+                mnColorStops.emplace_back(1.0, mnColorStops.back().getStopColor());
+            }
 
             // prepare unit range transform
             basegfx::B2DHomMatrix aPattern;
@@ -339,7 +322,7 @@ namespace drawinglayer::texture
                 const double fOffsetStart(cs_l->getStopOffset());
                 const double fOffsetEnd(cs_r->getStopOffset());
 
-                // same offset, empty ColorStopRange, continue with next step
+                // same offset, empty BColorStopRange, continue with next step
                 if (basegfx::fTools::equal(fOffsetStart, fOffsetEnd))
                     continue;
 
@@ -373,7 +356,10 @@ namespace drawinglayer::texture
             }
 
             if (bPenultimateUsed)
+            {
+                // correct temporary change
                 mnColorStops.pop_back();
+            }
         }
 
         void GeoTexSvxGradientAxial::modifyBColor(const basegfx::B2DPoint& rUV, basegfx::BColor& rBColor, double& /*rfOpacity*/) const
@@ -394,14 +380,14 @@ namespace drawinglayer::texture
             const double fScaler(basegfx::utils::getAxialGradientAlpha(rUV, maGradientInfo));
 
                 // we use the reverse ColorSteps here, so mirror scaler value
-            rBColor = basegfx::utils::modifyBColor(mnColorStops, 1.0 - fScaler, mnRequestedSteps, maLastColorStopRange);
+            rBColor = mnColorStops.getInterpolatedBColor(1.0 - fScaler, mnRequestedSteps, maLastColorStopRange);
         }
 
 
         GeoTexSvxGradientRadial::GeoTexSvxGradientRadial(
             const basegfx::B2DRange& rDefinitionRange,
             sal_uInt32 nRequestedSteps,
-            const basegfx::ColorStops& rColorStops,
+            const basegfx::BColorStops& rColorStops,
             double fBorder,
             double fOffsetX,
             double fOffsetY)
@@ -430,7 +416,13 @@ namespace drawinglayer::texture
                 return;
 
             // check if we need last-ColorStop-correction
-            const bool bPenultimateUsed(checkPenultimate());
+            const bool bPenultimateUsed(mnColorStops.checkPenultimate());
+
+            if (bPenultimateUsed)
+            {
+                // temporarily add a ColorStop entry
+                mnColorStops.emplace_back(1.0, mnColorStops.back().getStopColor());
+            }
 
             // outer loop over ColorStops, each is from cs_l to cs_r
             for (auto cs_l(mnColorStops.begin()), cs_r(cs_l + 1); cs_r != mnColorStops.end(); cs_l++, cs_r++)
@@ -439,7 +431,7 @@ namespace drawinglayer::texture
                 const double fOffsetStart(cs_l->getStopOffset());
                 const double fOffsetEnd(cs_r->getStopOffset());
 
-                // same offset, empty ColorStopRange, continue with next step
+                // same offset, empty BColorStopRange, continue with next step
                 if (basegfx::fTools::equal(fOffsetStart, fOffsetEnd))
                     continue;
 
@@ -468,7 +460,10 @@ namespace drawinglayer::texture
             }
 
             if (bPenultimateUsed)
+            {
+                // correct temporary change
                 mnColorStops.pop_back();
+            }
         }
 
         void GeoTexSvxGradientRadial::modifyBColor(const basegfx::B2DPoint& rUV, basegfx::BColor& rBColor, double& /*rfOpacity*/) const
@@ -486,14 +481,14 @@ namespace drawinglayer::texture
 
             // texture-back-transform X/Y -> t [0.0..1.0] and determine color
             const double fScaler(basegfx::utils::getRadialGradientAlpha(rUV, maGradientInfo));
-            rBColor = basegfx::utils::modifyBColor(mnColorStops, fScaler, mnRequestedSteps, maLastColorStopRange);
+            rBColor = mnColorStops.getInterpolatedBColor(fScaler, mnRequestedSteps, maLastColorStopRange);
         }
 
 
         GeoTexSvxGradientElliptical::GeoTexSvxGradientElliptical(
             const basegfx::B2DRange& rDefinitionRange,
             sal_uInt32 nRequestedSteps,
-            const basegfx::ColorStops& rColorStops,
+            const basegfx::BColorStops& rColorStops,
             double fBorder,
             double fOffsetX,
             double fOffsetY,
@@ -524,7 +519,13 @@ namespace drawinglayer::texture
                 return;
 
             // check if we need last-ColorStop-correction
-            const bool bPenultimateUsed(checkPenultimate());
+            const bool bPenultimateUsed(mnColorStops.checkPenultimate());
+
+            if (bPenultimateUsed)
+            {
+                // temporarily add a ColorStop entry
+                mnColorStops.emplace_back(1.0, mnColorStops.back().getStopColor());
+            }
 
             // prepare vars dependent on aspect ratio
             const double fAR(maGradientInfo.getAspectRatio());
@@ -537,7 +538,7 @@ namespace drawinglayer::texture
                 const double fOffsetStart(cs_l->getStopOffset());
                 const double fOffsetEnd(cs_r->getStopOffset());
 
-                // same offset, empty ColorStopRange, continue with next step
+                // same offset, empty BColorStopRange, continue with next step
                 if (basegfx::fTools::equal(fOffsetStart, fOffsetEnd))
                     continue;
 
@@ -569,7 +570,10 @@ namespace drawinglayer::texture
             }
 
             if (bPenultimateUsed)
+            {
+                // correct temporary change
                 mnColorStops.pop_back();
+            }
         }
 
         void GeoTexSvxGradientElliptical::modifyBColor(const basegfx::B2DPoint& rUV, basegfx::BColor& rBColor, double& /*rfOpacity*/) const
@@ -587,14 +591,14 @@ namespace drawinglayer::texture
 
             // texture-back-transform X/Y -> t [0.0..1.0] and determine color
             const double fScaler(basegfx::utils::getEllipticalGradientAlpha(rUV, maGradientInfo));
-            rBColor = basegfx::utils::modifyBColor(mnColorStops, fScaler, mnRequestedSteps, maLastColorStopRange);
+            rBColor = mnColorStops.getInterpolatedBColor(fScaler, mnRequestedSteps, maLastColorStopRange);
         }
 
 
         GeoTexSvxGradientSquare::GeoTexSvxGradientSquare(
             const basegfx::B2DRange& rDefinitionRange,
             sal_uInt32 nRequestedSteps,
-            const basegfx::ColorStops& rColorStops,
+            const basegfx::BColorStops& rColorStops,
             double fBorder,
             double fOffsetX,
             double fOffsetY,
@@ -625,7 +629,13 @@ namespace drawinglayer::texture
                 return;
 
             // check if we need last-ColorStop-correction
-            const bool bPenultimateUsed(checkPenultimate());
+            const bool bPenultimateUsed(mnColorStops.checkPenultimate());
+
+            if (bPenultimateUsed)
+            {
+                // temporarily add a ColorStop entry
+                mnColorStops.emplace_back(1.0, mnColorStops.back().getStopColor());
+            }
 
             // outer loop over ColorStops, each is from cs_l to cs_r
             for (auto cs_l(mnColorStops.begin()), cs_r(cs_l + 1); cs_r != mnColorStops.end(); cs_l++, cs_r++)
@@ -634,7 +644,7 @@ namespace drawinglayer::texture
                 const double fOffsetStart(cs_l->getStopOffset());
                 const double fOffsetEnd(cs_r->getStopOffset());
 
-                // same offset, empty ColorStopRange, continue with next step
+                // same offset, empty BColorStopRange, continue with next step
                 if (basegfx::fTools::equal(fOffsetStart, fOffsetEnd))
                     continue;
 
@@ -663,7 +673,10 @@ namespace drawinglayer::texture
             }
 
             if (bPenultimateUsed)
+            {
+                // correct temporary change
                 mnColorStops.pop_back();
+            }
         }
 
         void GeoTexSvxGradientSquare::modifyBColor(const basegfx::B2DPoint& rUV, basegfx::BColor& rBColor, double& /*rfOpacity*/) const
@@ -681,14 +694,14 @@ namespace drawinglayer::texture
 
             // texture-back-transform X/Y -> t [0.0..1.0] and determine color
             const double fScaler(basegfx::utils::getSquareGradientAlpha(rUV, maGradientInfo));
-            rBColor = basegfx::utils::modifyBColor(mnColorStops, fScaler, mnRequestedSteps, maLastColorStopRange);
+            rBColor = mnColorStops.getInterpolatedBColor(fScaler, mnRequestedSteps, maLastColorStopRange);
         }
 
 
         GeoTexSvxGradientRect::GeoTexSvxGradientRect(
             const basegfx::B2DRange& rDefinitionRange,
             sal_uInt32 nRequestedSteps,
-            const basegfx::ColorStops& rColorStops,
+            const basegfx::BColorStops& rColorStops,
             double fBorder,
             double fOffsetX,
             double fOffsetY,
@@ -719,7 +732,13 @@ namespace drawinglayer::texture
                 return;
 
             // check if we need last-ColorStop-correction
-            const bool bPenultimateUsed(checkPenultimate());
+            const bool bPenultimateUsed(mnColorStops.checkPenultimate());
+
+            if (bPenultimateUsed)
+            {
+                // temporarily add a ColorStop entry
+                mnColorStops.emplace_back(1.0, mnColorStops.back().getStopColor());
+            }
 
             // prepare vars dependent on aspect ratio
             const double fAR(maGradientInfo.getAspectRatio());
@@ -732,7 +751,7 @@ namespace drawinglayer::texture
                 const double fOffsetStart(cs_l->getStopOffset());
                 const double fOffsetEnd(cs_r->getStopOffset());
 
-                // same offset, empty ColorStopRange, continue with next step
+                // same offset, empty BColorStopRange, continue with next step
                 if (basegfx::fTools::equal(fOffsetStart, fOffsetEnd))
                     continue;
 
@@ -764,7 +783,10 @@ namespace drawinglayer::texture
             }
 
             if (bPenultimateUsed)
+            {
+                // correct temporary change
                 mnColorStops.pop_back();
+            }
         }
 
         void GeoTexSvxGradientRect::modifyBColor(const basegfx::B2DPoint& rUV, basegfx::BColor& rBColor, double& /*rfOpacity*/) const
@@ -782,7 +804,7 @@ namespace drawinglayer::texture
 
             // texture-back-transform X/Y -> t [0.0..1.0] and determine color
             const double fScaler(basegfx::utils::getRectangularGradientAlpha(rUV, maGradientInfo));
-            rBColor = basegfx::utils::modifyBColor(mnColorStops, fScaler, mnRequestedSteps, maLastColorStopRange);
+            rBColor = mnColorStops.getInterpolatedBColor(fScaler, mnRequestedSteps, maLastColorStopRange);
         }
 
 
diff --git a/drawinglayer/source/tools/wmfemfhelper.cxx b/drawinglayer/source/tools/wmfemfhelper.cxx
index 1b2b2d0a5abd..aa48149219f3 100644
--- a/drawinglayer/source/tools/wmfemfhelper.cxx
+++ b/drawinglayer/source/tools/wmfemfhelper.cxx
@@ -681,7 +681,7 @@ namespace wmfemfhelper
             static_cast<double>(rGradient.GetOfsX()) * 0.01,
             static_cast<double>(rGradient.GetOfsY()) * 0.01,
             toRadians(rGradient.GetAngle()),
-            basegfx::utils::createColorStopsFromStartEndColor(aStart, aEnd),
+            basegfx::BColorStops(aStart, aEnd),
             rGradient.GetSteps());
     }
 
@@ -882,11 +882,12 @@ namespace wmfemfhelper
         PropertyHolder const & rPropertyHolder)
     {
         drawinglayer::attribute::FillGradientAttribute aAttribute(createFillGradientAttribute(rGradient));
+        basegfx::BColor aSingleColor;
 
-        if(aAttribute.hasSingleColor())
+        if (aAttribute.getColorStops().isSingleColor(aSingleColor))
         {
             // not really a gradient. Create filled rectangle
-            return CreateColorWallpaper(rRange, aAttribute.getColorStops().front().getStopColor(), rPropertyHolder);
+            return CreateColorWallpaper(rRange, aSingleColor, rPropertyHolder);
         }
         else
         {
@@ -2052,8 +2053,9 @@ namespace wmfemfhelper
                             const Gradient& rGradient = pA->GetGradient();
                             drawinglayer::attribute::FillGradientAttribute aAttribute(createFillGradientAttribute(rGradient));
                             basegfx::B2DPolyPolygon aOutline(basegfx::utils::createPolygonFromRect(aRange));
+                            basegfx::BColor aSingleColor;
 
-                            if(aAttribute.hasSingleColor())
+                            if (aAttribute.getColorStops().isSingleColor(aSingleColor))
                             {
                                 // not really a gradient. Create filled rectangle
                                 createFillPrimitive(
@@ -2762,14 +2764,15 @@ namespace wmfemfhelper
                                 // check if gradient is a real gradient
                                 const Gradient& rGradient = pA->GetGradient();
                                 drawinglayer::attribute::FillGradientAttribute aAttribute(createFillGradientAttribute(rGradient));
+                                basegfx::BColor aSingleColor;
 
-                                if(aAttribute.hasSingleColor())
+                                if (aAttribute.getColorStops().isSingleColor(aSingleColor))
                                 {
                                     // not really a gradient; create UnifiedTransparencePrimitive2D
                                     rTargetHolders.Current().append(
                                         new drawinglayer::primitive2d::UnifiedTransparencePrimitive2D(
                                             std::move(xSubContent),
-                                            aAttribute.getColorStops().front().getStopColor().luminance()));
+                                            aSingleColor.luminance()));
                                 }
                                 else
                                 {
@@ -2882,14 +2885,15 @@ namespace wmfemfhelper
                                 // get and check if gradient is a real gradient
                                 const Gradient& rGradient = pMetaGradientExAction->GetGradient();
                                 drawinglayer::attribute::FillGradientAttribute aAttribute(createFillGradientAttribute(rGradient));
+                                basegfx::BColor aSingleColor;
 
-                                if(aAttribute.hasSingleColor())
+                                if (aAttribute.getColorStops().isSingleColor(aSingleColor))
                                 {
                                     // not really a gradient
                                     rTargetHolders.Current().append(
                                         new drawinglayer::primitive2d::PolyPolygonColorPrimitive2D(
                                             std::move(aPolyPolygon),
-                                            aAttribute.getColorStops().front().getStopColor()));
+                                            aSingleColor));
                                 }
                                 else
                                 {