drawinglayer/source/primitive2d/unifiedtransparenceprimitive2d.cxx

   1 /* -*- Mode: C++; tab-width: 4; indent-tabs-mode: nil; c-basic-offset: 4 -*- */
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  19
  20 #include <drawinglayer/primitive2d/unifiedtransparenceprimitive2d.hxx>
  21 #include <basegfx/polygon/b2dpolygon.hxx>
  22 #include <basegfx/polygon/b2dpolygontools.hxx>
  23 #include <basegfx/color/bcolor.hxx>
  24 #include <drawinglayer/primitive2d/PolygonHairlinePrimitive2D.hxx>
  25 #include <drawinglayer/primitive2d/PolyPolygonColorPrimitive2D.hxx>
  26 #include <drawinglayer/primitive2d/transparenceprimitive2d.hxx>
  27 #include <drawinglayer/primitive2d/drawinglayer_primitivetypes2d.hxx>
  28
  29
  30 using namespace com::sun::star;
  31
  32
  33 namespace drawinglayer::primitive2d
  34 {
  35         UnifiedTransparencePrimitive2D::UnifiedTransparencePrimitive2D(
  36             Primitive2DContainer&& aChildren,
  37             double fTransparence)
  38         :   GroupPrimitive2D(std::move(aChildren)),
  39             mfTransparence(fTransparence)
  40         {
  41         }
  42
  43         bool UnifiedTransparencePrimitive2D::operator==(const BasePrimitive2D& rPrimitive) const
  44         {
  45             if(GroupPrimitive2D::operator==(rPrimitive))
  46             {
  47                 const UnifiedTransparencePrimitive2D& rCompare = static_cast<const UnifiedTransparencePrimitive2D&>(rPrimitive);
  48
  49                 return (getTransparence() == rCompare.getTransparence());
  50             }
  51
  52             return false;
  53         }
  54
  55         basegfx::B2DRange UnifiedTransparencePrimitive2D::getB2DRange(const geometry::ViewInformation2D& rViewInformation) const
  56         {
  57             // do not use the fallback to decomposition here since for a correct BoundRect we also
  58             // need invisible (1.0 == getTransparence()) geometry; these would be deleted in the decomposition
  59             return getChildren().getB2DRange( rViewInformation);
  60         }
  61
  62         void UnifiedTransparencePrimitive2D::get2DDecomposition(Primitive2DDecompositionVisitor& rVisitor, const geometry::ViewInformation2D& rViewInformation) const
  63         {
  64             if(0.0 == getTransparence())
  65             {
  66                 // no transparence used, so just use the content
  67                 getChildren(rVisitor);
  68             }
  69             else if(getTransparence() > 0.0 && getTransparence() < 1.0)
  70             {
  71                 // The idea is to create a TransparencePrimitive2D with transparent content using a fill color
  72                 // corresponding to the transparence value. Problem is that in most systems, the right
  73                 // and bottom pixel array is not filled when filling polygons, thus this would not
  74                 // always produce a complete transparent bitmap. There are some solutions:
  75
  76                 // - Grow the used polygon range by one discrete unit in X and Y. This
  77                 // will make the decomposition view-dependent.
  78
  79                 // - For all filled polygon renderings, draw the polygon outline extra. This
  80                 // would lead to unwanted side effects when using concatenated polygons.
  81
  82                 // - At this decomposition, add a filled polygon and a hairline polygon. This
  83                 // solution stays view-independent.
  84
  85                 // I will take the last one here. The small overhead of two primitives will only be
  86                 // used when UnifiedTransparencePrimitive2D is not handled directly.
  87                 const basegfx::B2DRange aPolygonRange(getChildren().getB2DRange(rViewInformation));
  88                 basegfx::B2DPolygon aPolygon(basegfx::utils::createPolygonFromRect(aPolygonRange));
  89                 const basegfx::BColor aGray(getTransparence(), getTransparence(), getTransparence());
  90                 Primitive2DContainer aTransparenceContent(2);
  91
  92                 aTransparenceContent[0] = Primitive2DReference(new PolyPolygonColorPrimitive2D(basegfx::B2DPolyPolygon(aPolygon), aGray));
  93                 aTransparenceContent[1] = Primitive2DReference(new PolygonHairlinePrimitive2D(std::move(aPolygon), aGray));
  94
  95                 // create sub-transparence group with a gray-colored rectangular fill polygon
  96                 rVisitor.visit(new TransparencePrimitive2D(Primitive2DContainer(getChildren()), std::move(aTransparenceContent)));
  97             }
  98             else
  99             {
 100                 // completely transparent or invalid definition, add nothing
 101             }
 102         }
 103
 104         // provide unique ID
 105         sal_uInt32 UnifiedTransparencePrimitive2D::getPrimitive2DID() const
 106         {
 107             return PRIMITIVE2D_ID_UNIFIEDTRANSPARENCEPRIMITIVE2D;
 108         }
 109
 110 } // end of namespace
 111
 112 /* vim:set shiftwidth=4 softtabstop=4 expandtab: */