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21 
22 // MARKER(update_precomp.py): autogen include statement, do not remove
23 #include "precompiled_svgio.hxx"
24 
25 #include <svgio/svgreader/svgclippathnode.hxx>
26 #include <drawinglayer/primitive2d/transformprimitive2d.hxx>
27 #include <drawinglayer/primitive2d/maskprimitive2d.hxx>
28 #include <basegfx/matrix/b2dhommatrixtools.hxx>
29 #include <drawinglayer/geometry/viewinformation2d.hxx>
30 #include <drawinglayer/processor2d/contourextractor2d.hxx>
31 #include <basegfx/polygon/b2dpolypolygoncutter.hxx>
32 #include <basegfx/polygon/b2dpolygontools.hxx>
33 
34 //////////////////////////////////////////////////////////////////////////////
35 
36 namespace svgio
37 {
38     namespace svgreader
39     {
40         SvgClipPathNode::SvgClipPathNode(
41             SvgDocument& rDocument,
42             SvgNode* pParent)
43         :   SvgNode(SVGTokenClipPathNode, rDocument, pParent),
44             maSvgStyleAttributes(*this),
45             mpaTransform(0),
46             maClipPathUnits(userSpaceOnUse)
47         {
48         }
49 
50         SvgClipPathNode::~SvgClipPathNode()
51         {
52             if(mpaTransform) delete mpaTransform;
53         }
54 
55         const SvgStyleAttributes* SvgClipPathNode::getSvgStyleAttributes() const
56         {
57             return &maSvgStyleAttributes;
58         }
59 
60         void SvgClipPathNode::parseAttribute(const rtl::OUString& rTokenName, SVGToken aSVGToken, const rtl::OUString& aContent)
61         {
62             // call parent
63             SvgNode::parseAttribute(rTokenName, aSVGToken, aContent);
64 
65             // read style attributes
66             maSvgStyleAttributes.parseStyleAttribute(rTokenName, aSVGToken, aContent);
67 
68             // parse own
69             switch(aSVGToken)
70             {
71                 case SVGTokenStyle:
72                 {
73                     maSvgStyleAttributes.readStyle(aContent);
74                     break;
75                 }
76                 case SVGTokenTransform:
77                 {
78                     const basegfx::B2DHomMatrix aMatrix(readTransform(aContent, *this));
79 
80                     if(!aMatrix.isIdentity())
81                     {
82                         setTransform(&aMatrix);
83                     }
84                     break;
85                 }
86                 case SVGTokenClipPathUnits:
87                 {
88                     if(aContent.getLength())
89                     {
90                         if(aContent.match(commonStrings::aStrUserSpaceOnUse, 0))
91                         {
92                             setClipPathUnits(userSpaceOnUse);
93                         }
94                         else if(aContent.match(commonStrings::aStrObjectBoundingBox, 0))
95                         {
96                             setClipPathUnits(objectBoundingBox);
97                         }
98                     }
99                     break;
100                 }
101                 default:
102                 {
103                     break;
104                 }
105             }
106         }
107 
108         void SvgClipPathNode::decomposeSvgNode(drawinglayer::primitive2d::Primitive2DSequence& rTarget, bool bReferenced) const
109         {
110             drawinglayer::primitive2d::Primitive2DSequence aNewTarget;
111 
112             // decompose childs
113             SvgNode::decomposeSvgNode(aNewTarget, bReferenced);
114 
115             if(aNewTarget.hasElements())
116             {
117                 if(getTransform())
118                 {
119                     // create embedding group element with transformation
120                     const drawinglayer::primitive2d::Primitive2DReference xRef(
121                         new drawinglayer::primitive2d::TransformPrimitive2D(
122                             *getTransform(),
123                             aNewTarget));
124 
125                     drawinglayer::primitive2d::appendPrimitive2DReferenceToPrimitive2DSequence(rTarget, xRef);
126                 }
127                 else
128                 {
129                     // append to current target
130                     drawinglayer::primitive2d::appendPrimitive2DSequenceToPrimitive2DSequence(rTarget, aNewTarget);
131                 }
132             }
133         }
134 
135         void SvgClipPathNode::apply(drawinglayer::primitive2d::Primitive2DSequence& rContent) const
136         {
137             if(rContent.hasElements() && Display_none != getDisplay())
138             {
139                 const drawinglayer::geometry::ViewInformation2D aViewInformation2D;
140                 drawinglayer::primitive2d::Primitive2DSequence aClipTarget;
141                 basegfx::B2DPolyPolygon aClipPolyPolygon;
142 
143                 // get clipPath definition as primitives
144                 decomposeSvgNode(aClipTarget, true);
145 
146                 if(aClipTarget.hasElements())
147                 {
148                     // extract filled plygons as base for a mask PolyPolygon
149                     drawinglayer::processor2d::ContourExtractor2D aExtractor(aViewInformation2D, true);
150 
151                     aExtractor.process(aClipTarget);
152 
153                     const basegfx::B2DPolyPolygonVector& rResult(aExtractor.getExtractedContour());
154                     const sal_uInt32 nSize(rResult.size());
155 
156                     if(nSize > 1)
157                     {
158                         // merge to single clipPolyPolygon
159                         aClipPolyPolygon = basegfx::tools::mergeToSinglePolyPolygon(rResult);
160                     }
161                     else
162                     {
163                         aClipPolyPolygon = rResult[0];
164                     }
165                 }
166 
167                 if(aClipPolyPolygon.count())
168                 {
169                     if(objectBoundingBox == getClipPathUnits())
170                     {
171                         // clip is object-relative, transform using content transformation
172                         const basegfx::B2DRange aContentRange(
173                             drawinglayer::primitive2d::getB2DRangeFromPrimitive2DSequence(
174                                 rContent,
175                                 aViewInformation2D));
176 
177                         aClipPolyPolygon.transform(
178                             basegfx::tools::createScaleTranslateB2DHomMatrix(
179                                 aContentRange.getRange(),
180                                 aContentRange.getMinimum()));
181                     }
182 
183                     // #124313# try to avoid creating an embedding to a MaskPrimitive2D if
184                     // possible; MaskPrimitive2D processing is potentially expensive
185                     bool bCreateEmbedding(true);
186                     bool bAddContent(true);
187 
188                     if(basegfx::tools::isRectangle(aClipPolyPolygon))
189                     {
190                         // ClipRegion is a rectangle, thus it is not expensive to tell
191                         // if the content is completely inside or outside of it; get ranges
192                         const basegfx::B2DRange aClipRange(aClipPolyPolygon.getB2DRange());
193                         const basegfx::B2DRange aContentRange(
194                             drawinglayer::primitive2d::getB2DRangeFromPrimitive2DSequence(
195                                 rContent,
196                                 aViewInformation2D));
197 
198                         if(aClipRange.isInside(aContentRange))
199                         {
200                             // completely contained, no need to clip at all, so no need for embedding
201                             bCreateEmbedding = false;
202                         }
203                         else if(aClipRange.overlaps(aContentRange))
204                         {
205                             // overlap; embedding needed. ClipRegion can be minimized by using
206                             // the intersection of the ClipRange and the ContentRange. Minimizing
207                             // the ClipRegion potentially enhances further processing since
208                             // usually clip operations are expensive.
209                             basegfx::B2DRange aCommonRange(aContentRange);
210 
211                             aCommonRange.intersect(aClipRange);
212                             aClipPolyPolygon = basegfx::B2DPolyPolygon(basegfx::tools::createPolygonFromRect(aCommonRange));
213                         }
214                         else
215                         {
216                             // not inside and no overlap -> completely outside
217                             // no need for embedding, no need for content at all
218                             bCreateEmbedding = false;
219                             bAddContent = false;
220                         }
221                     }
222                     else
223                     {
224                         // ClipRegion is not a simple rectangle, it would be possible but expensive to
225                         // tell if the content needs clipping or not. It is also dependent of
226                         // the content's decomposition. To do this, a processor would be needed that
227                         // is capable if processing the given sequence of primitives and decide
228                         // if all is inside or all is outside. Such a ClipProcessor could be written,
229                         // but for now just create the embedding
230                     }
231 
232                     if(bCreateEmbedding)
233                     {
234                         // redefine target. Use MaskPrimitive2D with created clip
235                         // geometry. Using the automatically set mbIsClipPathContent at
236                         // SvgStyleAttributes the clip definition is without fill, stroke,
237                         // and strokeWidth and forced to black
238                         const drawinglayer::primitive2d::Primitive2DReference xEmbedTransparence(
239                             new drawinglayer::primitive2d::MaskPrimitive2D(
240                                 aClipPolyPolygon,
241                                 rContent));
242 
243                         rContent = drawinglayer::primitive2d::Primitive2DSequence(&xEmbedTransparence, 1);
244                     }
245                     else
246                     {
247                         if(!bAddContent)
248                         {
249                             rContent.realloc(0);
250                         }
251                     }
252                 }
253                 else
254                 {
255                     // An empty clipping path will completely clip away the element that had
256                     // the �clip-path� property applied. (Svg spec)
257                     rContent.realloc(0);
258                 }
259             }
260         }
261 
262     } // end of namespace svgreader
263 } // end of namespace svgio
264 
265 //////////////////////////////////////////////////////////////////////////////
266 // eof
267