include/basegfx/polygon/b2dtrapezoid.hxx

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  19
  20 #ifndef INCLUDED_BASEGFX_POLYGON_B2DTRAPEZOID_HXX
  21 #define INCLUDED_BASEGFX_POLYGON_B2DTRAPEZOID_HXX
  22
  23 #include <basegfx/polygon/b2dpolygon.hxx>
  24 #include <vector>
  25 #include <basegfx/basegfxdllapi.h>
  26
  27
  28 namespace basegfx { class B2DPolyPolygon; }
  29 namespace basegfx { class B2DPoint; }
  30
  31 namespace basegfx
  32 {
  33     // class to hold a single trapezoid
  34     class BASEGFX_DLLPUBLIC B2DTrapezoid
  35     {
  36     private:
  37         // Geometry data. YValues are down-oriented, this means bottom should
  38         // be bigger than top to be below it. The constructor implementation
  39         // guarantees:
  40
  41         // - mfBottomY >= mfTopY
  42         // - mfTopXRight >= mfTopXLeft
  43         // - mfBottomXRight >= mfBottomXLeft
  44         double              mfTopXLeft;
  45         double              mfTopXRight;
  46         double              mfTopY;
  47         double              mfBottomXLeft;
  48         double              mfBottomXRight;
  49         double              mfBottomY;
  50
  51     public:
  52         // constructor
  53         B2DTrapezoid(
  54             const double& rfTopXLeft,
  55             const double& rfTopXRight,
  56             const double& rfTopY,
  57             const double& rfBottomXLeft,
  58             const double& rfBottomXRight,
  59             const double& rfBottomY);
  60
  61         // data read access
  62         const double& getTopXLeft() const { return mfTopXLeft; }
  63         const double& getTopXRight() const { return mfTopXRight; }
  64         const double& getTopY() const { return mfTopY; }
  65         const double& getBottomXLeft() const { return mfBottomXLeft; }
  66         const double& getBottomXRight() const { return mfBottomXRight; }
  67         const double& getBottomY() const { return mfBottomY; }
  68
  69         // convenience method to get content as Polygon
  70         B2DPolygon getB2DPolygon() const;
  71     };
  72
  73     typedef ::std::vector< B2DTrapezoid > B2DTrapezoidVector;
  74
  75 } // end of namespace basegfx
  76
  77
  78 namespace basegfx
  79 {
  80     namespace utils
  81     {
  82         // convert SourcePolyPolygon to trapezoids. The trapezoids will be appended to
  83         // ro_Result. ro_Result will not be cleared. If SourcePolyPolygon contains curves,
  84         // it's default AdaptiveSubdivision will be used.
  85         // CAUTION: Trapezoids are orientation-dependent in the sense that the upper and lower
  86         // lines have to be parallel to the X-Axis, thus this subdivision is NOT simply usable
  87         // for primitive decompositions. To use it, the shear and rotate parts of the
  88         // involved transformations HAVE to be taken into account.
  89         BASEGFX_DLLPUBLIC void trapezoidSubdivide(
  90             B2DTrapezoidVector& ro_Result,
  91             const B2DPolyPolygon& rSourcePolyPolygon);
  92
  93         // directly create trapezoids from given edge. Depending on the given geometry,
  94         // none up to three trapezoids will be created
  95         BASEGFX_DLLPUBLIC void createLineTrapezoidFromEdge(
  96             B2DTrapezoidVector& ro_Result,
  97             const B2DPoint& rPointA,
  98             const B2DPoint& rPointB,
  99             double fLineWidth);
 100
 101         // create trapezoids for all edges of the given polygon. The closed state of
 102         // the polygon is taken into account. If curves are contained, the default
 103         // AdaptiveSubdivision will be used.
 104         BASEGFX_DLLPUBLIC void createLineTrapezoidFromB2DPolygon(
 105             B2DTrapezoidVector& ro_Result,
 106             const B2DPolygon& rPolygon,
 107             double fLineWidth);
 108
 109     } // end of namespace utils
 110 } // end of namespace basegfx
 111
 112
 113 #endif // INCLUDED_BASEGFX_POLYGON_B2DTRAPEZOID_HXX
 114
 115 /* vim:set shiftwidth=4 softtabstop=4 expandtab: */