include/basegfx/polygon/b2dlinegeometry.hxx

   1 /* -*- Mode: C++; tab-width: 4; indent-tabs-mode: nil; c-basic-offset: 4 -*- */
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  19
  20 #pragma once
  21
  22 #include <basegfx/numeric/ftools.hxx>
  23 #include <basegfx/polygon/b2dpolypolygon.hxx>
  24 #include <basegfx/polygon/b2dpolygon.hxx>
  25 #include <com/sun/star/drawing/LineCap.hpp>
  26 #include <basegfx/basegfxdllapi.h>
  27 #include <basegfx/polygon/b2dpolygontriangulator.hxx>
  28
  29 namespace basegfx::utils
  30 {
  31         /** Create line start/end geometry element, mostly arrows and things like that.
  32
  33             @param rCandidate
  34             The polygon which needs to get that line ends and needs to have two points
  35             at least.
  36
  37             @param rArrow
  38             The line start/end geometry. It is assumed that the tip is pointing
  39             upwards. Result will be rotated and scaled to fit.
  40
  41             @param bStart
  42             describes if creation is for start or end of candidate.
  43
  44             @param fWidth
  45             defines the size of the element, it's describing the target width in X
  46             of the arrow.
  47
  48             @param fDockingPosition needs to be in [0.0 ..1.0] range, where 0.0 means
  49             that the tip of the arrow will be aligned with the polygon start, 1.0 means
  50             the bottom. The default of 0.5 describes a centered arrow.
  51
  52             @param pConsumedLength
  53             Using this parameter it is possible to get back how much from the candidate
  54             geometry is overlapped by the created element (consumed).
  55
  56             @param fCandidateLength
  57             This should contain the length of rCandidate to allow work without
  58             again calculating the length (which may be expensive with beziers). If 0.0 is
  59             given, the length is calculated on demand.
  60
  61             @param fShift
  62             When it is necessary to count with the thickness of the line, it
  63             makes sense to move the start position slightly - so define the shift.
  64
  65             @return
  66             The Line start and end polygon, correctly rotated and scaled
  67         */
  68         BASEGFX_DLLPUBLIC B2DPolyPolygon createAreaGeometryForLineStartEnd(
  69             const B2DPolygon& rCandidate,
  70             const B2DPolyPolygon& rArrow,
  71             bool bStart,
  72             double fWidth,
  73             double fCandidateLength, // 0.0 -> calculate self
  74             double fDockingPosition, // 0->top, 1->bottom
  75             double* pConsumedLength = nullptr,
  76             double fShift = 0.0);
  77
  78         /** create filled polygon geometry for lines with a line width
  79
  80             This method will create bezier based, fillable polygons which
  81             will resample the curve if it was extended for the given half
  82             line width. It will remove extrema positions from contained
  83             bezier segments and get as close as possible and defined by
  84             the given parameters to the ideal result.
  85
  86             It will check edges for trivial bezier to avoid unnecessary
  87             bezier polygons. Care is taken to produce the in-between
  88             polygon points (the ones original on the source polygon) since
  89             it has showed that without those, the raster converters leave
  90             non-filled gaps.
  91
  92             @param rCandidate
  93             The source polygon defining the hairline polygon path
  94
  95             @param fHalfLineWidth
  96             The width of the line to one side
  97
  98             @param eJoin
  99             The LineJoin if the edges meeting in a point do not have a C1
 100             or C2 continuity
 101
 102             @param eCap
 103             The kind of cap, which is added to the line.
 104
 105             @param fMaxAllowedAngle
 106             Allows to hand over the maximum allowed angle between an edge and
 107             it's control vectors. The smaller, the more subdivisions will be
 108             needed to create the filled geometry. Allowed range is cropped to
 109             [M_PI_2 .. 0.01 * M_PI_2].
 110
 111             @param fMaxPartOfEdge
 112             Allows to influence from with relative length of a control vector
 113             compared to its edge a split is forced. The smaller, the more
 114             subdivisions will be needed to create the filled geometry. Allowed
 115             range is cropped to [1.0 .. 0.01]
 116
 117             @param fMiterMinimumAngle
 118             The minimum wanted angle between two edges when edge rounding
 119             is using miter. When an edge is smaller than this (tighter)
 120             the usual fallback to bevel is used. Allowed range is cropped
 121             to [M_PI .. 0.01 * M_PI].
 122
 123             Commit 51b5b93092d6231615de470c62494c24e54828a1 needs
 124             revert, we need the triangulation for X11 fat line drawing
 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 basegfx::utils
 146
 147 /* vim:set shiftwidth=4 softtabstop=4 expandtab: */