basegfx/source/range/b2xrange.cxx

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  27
  28 // MARKER(update_precomp.py): autogen include statement, do not remove
  29 #include "precompiled_basegfx.hxx"
  30
  31 #include <basegfx/range/b2drange.hxx>
  32 #include <basegfx/range/b2irange.hxx>
  33 #include <basegfx/range/b2ibox.hxx>
  34
  35
  36 namespace basegfx
  37 {
  38     namespace
  39     {
  40         /** Generic implementation of the difference set computation
  41
  42             @tpl RangeType
  43             Type to operate on. Must provide ValueType and TraitsType
  44             nested types.
  45          */
  46         template< class RangeType > void doComputeSetDifference(
  47             ::std::vector< RangeType >& o_rRanges,
  48             const RangeType&            a,
  49             const RangeType&            b )
  50         {
  51             o_rRanges.clear();
  52
  53             // special-casing the empty rect case (this will fail most
  54             // of the times below, because of the DBL_MIN/MAX special
  55             // values denoting emptyness in the rectangle.
  56             if( a.isEmpty() )
  57             {
  58                 o_rRanges.push_back( b );
  59                 return;
  60             }
  61             if( b.isEmpty() )
  62             {
  63                 o_rRanges.push_back( a );
  64                 return;
  65             }
  66
  67             const typename RangeType::ValueType                     ax(a.getMinX());
  68             const typename RangeType::ValueType                     ay(a.getMinY());
  69             const typename RangeType::TraitsType::DifferenceType    aw(a.getWidth());
  70             const typename RangeType::TraitsType::DifferenceType    ah(a.getHeight());
  71             const typename RangeType::ValueType                     bx(b.getMinX());
  72             const typename RangeType::ValueType                     by(b.getMinY());
  73             const typename RangeType::TraitsType::DifferenceType    bw(b.getWidth());
  74             const typename RangeType::TraitsType::DifferenceType    bh(b.getHeight());
  75
  76             const typename RangeType::TraitsType::DifferenceType    h0( (by > ay) ? by - ay : 0 );
  77             const typename RangeType::TraitsType::DifferenceType    h3( (by + bh < ay + ah) ? ay + ah - by - bh : 0 );
  78             const typename RangeType::TraitsType::DifferenceType    w1( (bx > ax) ? bx - ax : 0 );
  79             const typename RangeType::TraitsType::DifferenceType    w2( (ax + aw > bx + bw) ? ax + aw - bx - bw : 0 );
  80             const typename RangeType::TraitsType::DifferenceType    h12( (h0 + h3 < ah) ? ah - h0 - h3 : 0 );
  81
  82             // TODO(E2): Use numeric_cast instead of static_cast here,
  83             // need range checks!
  84             if (h0 > 0)
  85                 o_rRanges.push_back(
  86                     RangeType(ax,ay,
  87                               static_cast<typename RangeType::ValueType>(ax+aw),
  88                               static_cast<typename RangeType::ValueType>(ay+h0)) );
  89
  90             if (w1 > 0 && h12 > 0)
  91                 o_rRanges.push_back(
  92                     RangeType(ax,
  93                               static_cast<typename RangeType::ValueType>(ay+h0),
  94                               static_cast<typename RangeType::ValueType>(ax+w1),
  95                               static_cast<typename RangeType::ValueType>(ay+h0+h12)) );
  96
  97             if (w2 > 0 && h12 > 0)
  98                 o_rRanges.push_back(
  99                     RangeType(static_cast<typename RangeType::ValueType>(bx+bw),
 100                               static_cast<typename RangeType::ValueType>(ay+h0),
 101                               static_cast<typename RangeType::ValueType>(bx+bw+w2),
 102                               static_cast<typename RangeType::ValueType>(ay+h0+h12)) );
 103
 104             if (h3 > 0)
 105                 o_rRanges.push_back(
 106                     RangeType(ax,
 107                               static_cast<typename RangeType::ValueType>(ay+h0+h12),
 108                               static_cast<typename RangeType::ValueType>(ax+aw),
 109                               static_cast<typename RangeType::ValueType>(ay+h0+h12+h3)) );
 110         }
 111     }
 112
 113     ::std::vector< B2IRange >& computeSetDifference( ::std::vector< B2IRange >& o_rResult,
 114                                                      const B2IRange&            rFirst,
 115                                                      const B2IRange&            rSecond )
 116     {
 117         doComputeSetDifference( o_rResult, rFirst, rSecond );
 118
 119         return o_rResult;
 120     }
 121
 122     ::std::vector< B2DRange >& computeSetDifference( ::std::vector< B2DRange >& o_rResult,
 123                                                      const B2DRange&            rFirst,
 124                                                      const B2DRange&            rSecond )
 125     {
 126         doComputeSetDifference( o_rResult, rFirst, rSecond );
 127
 128         return o_rResult;
 129     }
 130
 131     ::std::vector< B2IBox >& computeSetDifference( ::std::vector< B2IBox >& o_rResult,
 132                                                    const B2IBox&            rFirst,
 133                                                    const B2IBox&            rSecond )
 134     {
 135         doComputeSetDifference( o_rResult, rFirst, rSecond );
 136
 137         return o_rResult;
 138     }
 139
 140 } // end of namespace basegfx
 141
 142 // eof