basegfx/source/range/b2xrange.cxx

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  30
  31 // MARKER(update_precomp.py): autogen include statement, do not remove
  32 #include "precompiled_basegfx.hxx"
  33
  34 #include <basegfx/range/b2drange.hxx>
  35 #include <basegfx/range/b2irange.hxx>
  36 #include <basegfx/range/b2ibox.hxx>
  37
  38
  39 namespace basegfx
  40 {
  41     namespace
  42     {
  43         /** Generic implementation of the difference set computation
  44
  45             @tpl RangeType
  46             Type to operate on. Must provide ValueType and TraitsType
  47             nested types.
  48          */
  49         template< class RangeType > void doComputeSetDifference(
  50             ::std::vector< RangeType >& o_rRanges,
  51             const RangeType&                    a,
  52             const RangeType&                    b )
  53         {
  54             o_rRanges.clear();
  55
  56             // special-casing the empty rect case (this will fail most
  57             // of the times below, because of the DBL_MIN/MAX special
  58             // values denoting emptyness in the rectangle.
  59             if( a.isEmpty() )
  60             {
  61                 o_rRanges.push_back( b );
  62                 return;
  63             }
  64             if( b.isEmpty() )
  65             {
  66                 o_rRanges.push_back( a );
  67                 return;
  68             }
  69
  70             const typename RangeType::ValueType                                         ax(a.getMinX());
  71             const typename RangeType::ValueType                                         ay(a.getMinY());
  72             const typename RangeType::TraitsType::DifferenceType        aw(a.getWidth());
  73             const typename RangeType::TraitsType::DifferenceType        ah(a.getHeight());
  74             const typename RangeType::ValueType                                         bx(b.getMinX());
  75             const typename RangeType::ValueType                                         by(b.getMinY());
  76             const typename RangeType::TraitsType::DifferenceType        bw(b.getWidth());
  77             const typename RangeType::TraitsType::DifferenceType        bh(b.getHeight());
  78
  79             const typename RangeType::TraitsType::DifferenceType        h0( (by > ay) ? by - ay : 0 );
  80             const typename RangeType::TraitsType::DifferenceType        h3( (by + bh < ay + ah) ? ay + ah - by - bh : 0 );
  81             const typename RangeType::TraitsType::DifferenceType        w1( (bx > ax) ? bx - ax : 0 );
  82             const typename RangeType::TraitsType::DifferenceType        w2( (ax + aw > bx + bw) ? ax + aw - bx - bw : 0 );
  83             const typename RangeType::TraitsType::DifferenceType        h12( (h0 + h3 < ah) ? ah - h0 - h3 : 0 );
  84
  85             // TODO(E2): Use numeric_cast instead of static_cast here,
  86             // need range checks!
  87             if (h0 > 0)
  88                 o_rRanges.push_back(
  89                     RangeType(ax,ay,
  90                               static_cast<typename RangeType::ValueType>(ax+aw),
  91                               static_cast<typename RangeType::ValueType>(ay+h0)) );
  92
  93             if (w1 > 0 && h12 > 0)
  94                 o_rRanges.push_back(
  95                     RangeType(ax,
  96                               static_cast<typename RangeType::ValueType>(ay+h0),
  97                               static_cast<typename RangeType::ValueType>(ax+w1),
  98                               static_cast<typename RangeType::ValueType>(ay+h0+h12)) );
  99
 100             if (w2 > 0 && h12 > 0)
 101                 o_rRanges.push_back(
 102                     RangeType(static_cast<typename RangeType::ValueType>(bx+bw),
 103                               static_cast<typename RangeType::ValueType>(ay+h0),
 104                               static_cast<typename RangeType::ValueType>(bx+bw+w2),
 105                               static_cast<typename RangeType::ValueType>(ay+h0+h12)) );
 106
 107             if (h3 > 0)
 108                 o_rRanges.push_back(
 109                     RangeType(ax,
 110                               static_cast<typename RangeType::ValueType>(ay+h0+h12),
 111                               static_cast<typename RangeType::ValueType>(ax+aw),
 112                               static_cast<typename RangeType::ValueType>(ay+h0+h12+h3)) );
 113         }
 114     }
 115
 116     ::std::vector< B2IRange >& computeSetDifference( ::std::vector< B2IRange >& o_rResult,
 117                                                      const B2IRange&                    rFirst,
 118                                                      const B2IRange&                    rSecond )
 119     {
 120         doComputeSetDifference( o_rResult, rFirst, rSecond );
 121
 122         return o_rResult;
 123     }
 124
 125     ::std::vector< B2DRange >& computeSetDifference( ::std::vector< B2DRange >& o_rResult,
 126                                                      const B2DRange&                    rFirst,
 127                                                      const B2DRange&                    rSecond )
 128     {
 129         doComputeSetDifference( o_rResult, rFirst, rSecond );
 130
 131         return o_rResult;
 132     }
 133
 134     ::std::vector< B2IBox >& computeSetDifference( ::std::vector< B2IBox >&     o_rResult,
 135                                                    const B2IBox&                        rFirst,
 136                                                    const B2IBox&                        rSecond )
 137     {
 138         doComputeSetDifference( o_rResult, rFirst, rSecond );
 139
 140         return o_rResult;
 141     }
 142
 143 } // end of namespace basegfx
 144
 145 // eof