include/basegfx/polygon/b2dlinegeometry.hxx

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  19
  20 #ifndef INCLUDED_BASEGFX_POLYGON_B2DLINEGEOMETRY_HXX
  21 #define INCLUDED_BASEGFX_POLYGON_B2DLINEGEOMETRY_HXX
  22
  23 #include <basegfx/numeric/ftools.hxx>
  24 #include <basegfx/polygon/b2dpolypolygon.hxx>
  25 #include <basegfx/polygon/b2dpolygon.hxx>
  26 #include <com/sun/star/drawing/LineCap.hpp>
  27 #include <basegfx/basegfxdllapi.h>
  28 #include <basegfx/polygon/b2dpolygontriangulator.hxx>
  29
  30 namespace basegfx
  31 {
  32     namespace utils
  33     {
  34         /** Create line start/end geometry element, mostly arrows and things like that.
  35
  36             @param rCandidate
  37             The polygon which needs to get that line ends and needs to have two points
  38             at least.
  39
  40             @param rArrow
  41             The line start/end geometry. It is assumed that the tip is pointing
  42             upwards. Result will be rotated and scaled to fit.
  43
  44             @param bStart
  45             describes if creation is for start or end of candidate.
  46
  47             @param fWidth
  48             defines the size of the element, it's describing the target width in X
  49             of the arrow.
  50
  51             @param fDockingPosition needs to be in [0.0 ..1.0] range, where 0.0 means
  52             that the tip of the arrow will be aligned with the polygon start, 1.0 means
  53             the bottom. The default of 0.5 describes a centered arrow.
  54
  55             @param pConsumedLength
  56             Using this parameter it is possible to get back how much from the candidate
  57             geometry is overlapped by the created element (consumed).
  58
  59             @param fCandidateLength
  60             This should contain the length of rCandidate to allow work without
  61             again calculating the length (which may be expensive with beziers). If 0.0 is
  62             given, the length is calculated on demand.
  63
  64             @param fShift
  65             When it is necessary to count with the thickness of the line, it
  66             makes sense to move the start position slightly - so define the shift.
  67
  68             @return
  69             The Line start and end polygon, correctly rotated and scaled
  70         */
  71         BASEGFX_DLLPUBLIC B2DPolyPolygon createAreaGeometryForLineStartEnd(
  72             const B2DPolygon& rCandidate,
  73             const B2DPolyPolygon& rArrow,
  74             bool bStart,
  75             double fWidth,
  76             double fCandidateLength, // 0.0 -> calculate self
  77             double fDockingPosition, // 0->top, 1->bottom
  78             double* pConsumedLength = nullptr,
  79             double fShift = 0.0);
  80
  81         /** create filled polygon geometry for lines with a line width
  82
  83             This method will create bezier based, fillable polygons which
  84             will resample the curve if it was extended for the given half
  85             line width. It will remove extrema positions from contained
  86             bezier segments and get as close as possible and defined by
  87             the given parameters to the ideal result.
  88
  89             It will check edges for trivial bezier to avoid unnecessary
  90             bezier polygons. Care is taken to produce the in-between
  91             polygon points (the ones original on the source polygon) since
  92             it has showed that without those, the raster converters leave
  93             non-filled gaps.
  94
  95             @param rCandidate
  96             The source polygon defining the hairline polygon path
  97
  98             @param fHalfLineWidth
  99             The width of the line to one side
 100
 101             @param eJoin
 102             The LineJoin if the edges meeting in a point do not have a C1
 103             or C2 continuity
 104
 105             @param eCap
 106             The kind of cap, which is added to the line.
 107
 108             @param fMaxAllowedAngle
 109             Allows to hand over the maximum allowed angle between an edge and
 110             it's control vectors. The smaller, the more subdivisions will be
 111             needed to create the filled geometry. Allowed range is cropped to
 112             [F_PI2 .. 0.01 * F_PI2].
 113
 114             @param fMaxPartOfEdge
 115             Allows to influence from with relative length of a control vector
 116             compared to its edge a split is forced. The smaller, the more
 117             subdivisions will be needed to create the filled geometry. Allowed
 118             range is cropped to [1.0 .. 0.01]
 119
 120             @param fMiterMinimumAngle
 121             The minimum wanted angle between two edges when edge rounding
 122             is using miter. When an edge is smaller than this (tighter)
 123             the usual fallback to bevel is used. Allowed range is cropped
 124             to [F_PI .. 0.01 * F_PI].
 125
 126             @param pTriangles
 127             If given, the method will additionally add the created geometry as
 128             B2DTriangle's
 129
 130             @return
 131             The tools::PolyPolygon containing the geometry of the extended line by
 132             it's line width. Contains bezier segments and edge roundings as
 133             needed and defined.
 134         */
 135         BASEGFX_DLLPUBLIC B2DPolyPolygon createAreaGeometry(
 136             const B2DPolygon& rCandidate,
 137             double fHalfLineWidth,
 138             B2DLineJoin eJoin,
 139             css::drawing::LineCap eCap,
 140             double fMaxAllowedAngle = basegfx::deg2rad(12.5),
 141             double fMaxPartOfEdge = 0.4,
 142             double fMiterMinimumAngle = basegfx::deg2rad(15.0),
 143             basegfx::triangulator::B2DTriangleVector* pTriangles = nullptr);
 144
 145     } // end of namespace utils
 146 } // end of namespace basegfx
 147
 148 #endif // INCLUDED_BASEGFX_POLYGON_B2DLINEGEOMETRY_HXX
 149
 150 /* vim:set shiftwidth=4 softtabstop=4 expandtab: */