drawinglayer/source/primitive2d/unifiedalphaprimitive2d.cxx

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   2  *
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   5  *  $RCSfile: unifiedalphaprimitive2d.cxx,v $
   6  *
   7  *  $Revision: 1.5 $
   8  *
   9  *  last change: $Author: aw $ $Date: 2008-05-27 14:11:20 $
  10  *
  11  *  The Contents of this file are made available subject to
  12  *  the terms of GNU Lesser General Public License Version 2.1.
  13  *
  14  *
  15  *    GNU Lesser General Public License Version 2.1
  16  *    =============================================
  17  *    Copyright 2005 by Sun Microsystems, Inc.
  18  *    901 San Antonio Road, Palo Alto, CA 94303, USA
  19  *
  20  *    This library is free software; you can redistribute it and/or
  21  *    modify it under the terms of the GNU Lesser General Public
  22  *    License version 2.1, as published by the Free Software Foundation.
  23  *
  24  *    This library is distributed in the hope that it will be useful,
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  26  *    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  27  *    Lesser General Public License for more details.
  28  *
  29  *    You should have received a copy of the GNU Lesser General Public
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  31  *    Foundation, Inc., 59 Temple Place, Suite 330, Boston,
  32  *    MA  02111-1307  USA
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  34  ************************************************************************/
  35
  36 // MARKER(update_precomp.py): autogen include statement, do not remove
  37 #include "precompiled_drawinglayer.hxx"
  38
  39 #include <drawinglayer/primitive2d/unifiedalphaprimitive2d.hxx>
  40 #include <basegfx/polygon/b2dpolygon.hxx>
  41 #include <basegfx/polygon/b2dpolygontools.hxx>
  42 #include <basegfx/color/bcolor.hxx>
  43 #include <drawinglayer/primitive2d/polypolygonprimitive2d.hxx>
  44 #include <drawinglayer/primitive2d/alphaprimitive2d.hxx>
  45 #include <drawinglayer/primitive2d/drawinglayer_primitivetypes2d.hxx>
  46 #include <drawinglayer/primitive2d/polygonprimitive2d.hxx>
  47
  48 //////////////////////////////////////////////////////////////////////////////
  49
  50 using namespace com::sun::star;
  51
  52 //////////////////////////////////////////////////////////////////////////////
  53
  54 namespace drawinglayer
  55 {
  56     namespace primitive2d
  57     {
  58         Primitive2DSequence UnifiedAlphaPrimitive2D::createLocalDecomposition(const geometry::ViewInformation2D& rViewInformation) const
  59         {
  60             if(0.0 == getAlpha())
  61             {
  62                 // no transparence used, so just use the content
  63                 return getChildren();
  64             }
  65             else if(getAlpha() > 0.0 && getAlpha() < 1.0)
  66             {
  67                 // The idea is to create a AlphaPrimitive2D with alpha content using a fill color
  68                 // corresponding to the alpha value. Problem is that in most systems, the right
  69                 // and bottom pixel array is not filled when filling polygons, thus this would not
  70                 // always produce a complete alpha bitmap. There are some solutions:
  71                 //
  72                 // - Grow the used polygon range by one discrete unit in X and Y. This
  73                 // will make the decomposition view-dependent.
  74                 //
  75                 // - For all filled polygon renderings, dra wthe polygon outline extra. This
  76                 // would lead to unwanted side effects when using concatenated polygons.
  77                 //
  78                 // - At this decomposition, add a filled polygon and a hairline polygon. This
  79                 // solution stays view-independent.
  80                 //
  81                 // I will take the last one here. The small overhead of two primitives will only be
  82                 // used when UnifiedAlphaPrimitive2D is not handled directly.
  83                 const basegfx::B2DRange aPolygonRange(getB2DRangeFromPrimitive2DSequence(getChildren(), rViewInformation));
  84                 const basegfx::B2DPolygon aPolygon(basegfx::tools::createPolygonFromRect(aPolygonRange));
  85                 const basegfx::BColor aGray(getAlpha(), getAlpha(), getAlpha());
  86                 Primitive2DSequence aAlphaContent(2);
  87
  88                 aAlphaContent[0] = Primitive2DReference(new PolyPolygonColorPrimitive2D(basegfx::B2DPolyPolygon(aPolygon), aGray));
  89                 aAlphaContent[1] = Primitive2DReference(new PolygonHairlinePrimitive2D(aPolygon, aGray));
  90
  91                 // create sub-transparence group with a gray-colored rectangular fill polygon
  92                 const Primitive2DReference xRefB(new AlphaPrimitive2D(getChildren(), aAlphaContent));
  93                 return Primitive2DSequence(&xRefB, 1L);
  94             }
  95             else
  96             {
  97                 // completely transparent or invalid definition, add nothing
  98                 return Primitive2DSequence();
  99             }
 100         }
 101
 102         UnifiedAlphaPrimitive2D::UnifiedAlphaPrimitive2D(
 103             const Primitive2DSequence& rChildren,
 104             double fAlpha)
 105         :       GroupPrimitive2D(rChildren),
 106             mfAlpha(fAlpha)
 107         {
 108         }
 109
 110         bool UnifiedAlphaPrimitive2D::operator==(const BasePrimitive2D& rPrimitive) const
 111         {
 112             if(GroupPrimitive2D::operator==(rPrimitive))
 113             {
 114                 const UnifiedAlphaPrimitive2D& rCompare = (UnifiedAlphaPrimitive2D&)rPrimitive;
 115
 116                 return (getAlpha() == rCompare.getAlpha());
 117             }
 118
 119             return false;
 120         }
 121
 122         // provide unique ID
 123         ImplPrimitrive2DIDBlock(UnifiedAlphaPrimitive2D, PRIMITIVE2D_ID_UNIFIEDALPHAPRIMITIVE2D)
 124
 125     } // end of namespace primitive2d
 126 } // end of namespace drawinglayer
 127
 128 //////////////////////////////////////////////////////////////////////////////
 129 // eof