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 <sal/types.h>
  24 #include <basegfx/numeric/ftools.hxx>
  25 #include <basegfx/polygon/b2dpolypolygon.hxx>
  26 #include <basegfx/polygon/b2dpolygon.hxx>
  27 #include <com/sun/star/drawing/LineCap.hpp>
  28 #include <basegfx/basegfxdllapi.h>
  29
  30
  31
  32 namespace basegfx
  33 {
  34     namespace tools
  35     {
  36         /** Create line start/end geometry element, mostly arrows and things like that.
  37
  38             @param rCandidate
  39             The polygon which needs to get that line ends and needs to have two points
  40             at least.
  41
  42             @param rArrow
  43             The line start/end geometry. It is assumed that the tip is pointing
  44             upwards. Result will be rotated and scaled to fit.
  45
  46             @param bStart
  47             describes if creation is for start or end of candidate.
  48
  49             @param fWidth
  50             defines the size of the element, it's describing the target width in X
  51             of the arrow.
  52
  53             @param fDockingPosition needs to be in [0.0 ..1.0] range, where 0.0 means
  54             that the tip of the arrow will be aligned with the polygon start, 1.0 means
  55             the bottom. The default of 0.5 describes a centered arrow.
  56
  57             @param pConsumedLength
  58             Using this parameter it is possible to get back how much from the candidate
  59             geometry is overlapped by the created element (consumed).
  60
  61             @param fCandidateLength
  62             This should contain the length of rCandidate to allow work without
  63             again calculating the length (which may be expensive with beziers). If 0.0 is
  64             given, the length is calculated on demand.
  65
  66             @param fShift
  67             When it is necessary to count with the thickness of the line, it
  68             makes sense to move the start position slightly - so define the shift.
  69
  70             @return
  71             The Line start and end polygon, correctly rotated and scaled
  72         */
  73         BASEGFX_DLLPUBLIC B2DPolyPolygon createAreaGeometryForLineStartEnd(
  74             const B2DPolygon& rCandidate,
  75             const B2DPolyPolygon& rArrow,
  76             bool bStart,
  77             double fWidth,
  78             double fCandidateLength = 0.0, // 0.0 -> calculate self
  79             double fDockingPosition = 0.5, // 0->top, 1->bottom
  80             double* pConsumedLength = 0L,
  81             double fShift = 0.0);
  82
  83         /** create filled polygon geometry for lines with a line width
  84
  85             This method will create bezier based, fillable polygons which
  86             will resample the curve if it was extended for the given half
  87             line width. It will remove extrema positions from contained
  88             bezier segments and get as close as possible and defined by
  89             the given parameters to the ideal result.
  90
  91             It will check edges for trivial bezier to avoid unnecessary
  92             bezier polygons. Care is taken to produce the in-between
  93             polygon points (the ones original on the source poygon) since
  94             it has showed that without those, the raster converters leave
  95             non-filled gaps.
  96
  97             @param rCandidate
  98             The source polygon defining the hairline polygon path
  99
 100             @param fHalfLineWidth
 101             The width of the line to one side
 102
 103             @param eJoin
 104             The LineJoin if the edges meeting in a point do not have a C1
 105             or C2 continuity
 106
 107             @param eCap
 108             The kind of cap, which is added to the line.
 109
 110             @param fMaxAllowedAngle
 111             Allows to hand over the maximum allowed angle between an edge and
 112             it's control vectors. The smaller, the more subdivisions will be
 113             needed to create the filled geometry. Allowed range is cropped to
 114             [F_PI2 .. 0.01 * F_PI2].
 115
 116             @param fMaxPartOfEdge
 117             Allows to influence from with relative length of a control vector
 118             compared to it's edge a split is forced. The smaller, the more
 119             subdivisions will be needed to create the filled geometry. Allowed
 120             range is cropped to [1.0 .. 0.01]
 121
 122             @praram fMiterMinimumAngle
 123             The minimum wanted angle between two edges when edge rounding
 124             is using miter. When an edge is smaller than this (tighter)
 125             the usual fallback to bevel is used. Allowed range is cropped
 126             to [F_PI .. 0.01 * F_PI].
 127
 128             @return
 129             The PolyPolygon containing the geometry of the extended line by
 130             it's line width. Contains bezier segments and edge roundings as
 131             needed and defined.
 132         */
 133         BASEGFX_DLLPUBLIC B2DPolyPolygon createAreaGeometry(
 134             const B2DPolygon& rCandidate,
 135             double fHalfLineWidth,
 136             B2DLineJoin eJoin = B2DLINEJOIN_ROUND,
 137             com::sun::star::drawing::LineCap eCap = com::sun::star::drawing::LineCap_BUTT,
 138             double fMaxAllowedAngle = (12.5 * F_PI180),
 139             double fMaxPartOfEdge = 0.4,
 140             double fMiterMinimumAngle = (15.0 * F_PI180));
 141     } // end of namespace tools
 142 } // end of namespace basegfx
 143
 144 #endif // INCLUDED_BASEGFX_POLYGON_B2DLINEGEOMETRY_HXX
 145
 146 /* vim:set shiftwidth=4 softtabstop=4 expandtab: */