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
  28 namespace basegfx::utils
  29 {
  30         /** Create line start/end geometry element, mostly arrows and things like that.
  31
  32             @param rCandidate
  33             The polygon which needs to get that line ends and needs to have two points
  34             at least.
  35
  36             @param rArrow
  37             The line start/end geometry. It is assumed that the tip is pointing
  38             upwards. Result will be rotated and scaled to fit.
  39
  40             @param bStart
  41             describes if creation is for start or end of candidate.
  42
  43             @param fWidth
  44             defines the size of the element, it's describing the target width in X
  45             of the arrow.
  46
  47             @param fDockingPosition needs to be in [0.0 ..1.0] range, where 0.0 means
  48             that the tip of the arrow will be aligned with the polygon start, 1.0 means
  49             the bottom. The default of 0.5 describes a centered arrow.
  50
  51             @param pConsumedLength
  52             Using this parameter it is possible to get back how much from the candidate
  53             geometry is overlapped by the created element (consumed).
  54
  55             @param fCandidateLength
  56             This should contain the length of rCandidate to allow work without
  57             again calculating the length (which may be expensive with beziers). If 0.0 is
  58             given, the length is calculated on demand.
  59
  60             @param fShift
  61             When it is necessary to count with the thickness of the line, it
  62             makes sense to move the start position slightly - so define the shift.
  63
  64             @return
  65             The Line start and end polygon, correctly rotated and scaled
  66         */
  67         BASEGFX_DLLPUBLIC B2DPolyPolygon createAreaGeometryForLineStartEnd(
  68             const B2DPolygon& rCandidate,
  69             const B2DPolyPolygon& rArrow,
  70             bool bStart,
  71             double fWidth,
  72             double fCandidateLength, // 0.0 -> calculate self
  73             double fDockingPosition, // 0->top, 1->bottom
  74             double* pConsumedLength = nullptr,
  75             double fShift = 0.0);
  76
  77         /** create filled polygon geometry for lines with a line width
  78
  79             This method will create bezier based, fillable polygons which
  80             will resample the curve if it was extended for the given half
  81             line width. It will remove extrema positions from contained
  82             bezier segments and get as close as possible and defined by
  83             the given parameters to the ideal result.
  84
  85             It will check edges for trivial bezier to avoid unnecessary
  86             bezier polygons. Care is taken to produce the in-between
  87             polygon points (the ones original on the source polygon) since
  88             it has showed that without those, the raster converters leave
  89             non-filled gaps.
  90
  91             @param rCandidate
  92             The source polygon defining the hairline polygon path
  93
  94             @param fHalfLineWidth
  95             The width of the line to one side
  96
  97             @param eJoin
  98             The LineJoin if the edges meeting in a point do not have a C1
  99             or C2 continuity
 100
 101             @param eCap
 102             The kind of cap, which is added to the line.
 103
 104             @param fMaxAllowedAngle
 105             Allows to hand over the maximum allowed angle between an edge and
 106             it's control vectors. The smaller, the more subdivisions will be
 107             needed to create the filled geometry. Allowed range is cropped to
 108             [M_PI_2 .. 0.01 * M_PI_2].
 109
 110             @param fMaxPartOfEdge
 111             Allows to influence from with relative length of a control vector
 112             compared to its edge a split is forced. The smaller, the more
 113             subdivisions will be needed to create the filled geometry. Allowed
 114             range is cropped to [1.0 .. 0.01]
 115
 116             @param fMiterMinimumAngle
 117             The minimum wanted angle between two edges when edge rounding
 118             is using miter. When an edge is smaller than this (tighter)
 119             the usual fallback to bevel is used. Allowed range is cropped
 120             to [M_PI .. 0.01 * M_PI].
 121
 122             Commit 51b5b93092d6231615de470c62494c24e54828a1 needs
 123             revert, we need the triangulation for X11 fat line drawing
 124
 125             @param pTriangles
 126             If given, the method will additionally add the created geometry as
 127             B2DTriangle's
 128
 129             @return
 130             The tools::PolyPolygon containing the geometry of the extended line by
 131             it's line width. Contains bezier segments and edge roundings as
 132             needed and defined.
 133         */
 134         BASEGFX_DLLPUBLIC B2DPolyPolygon createAreaGeometry(
 135             const B2DPolygon& rCandidate,
 136             double fHalfLineWidth,
 137             B2DLineJoin eJoin,
 138             css::drawing::LineCap eCap,
 139             double fMaxAllowedAngle = basegfx::deg2rad(12.5),
 140             double fMaxPartOfEdge = 0.4,
 141             double fMiterMinimumAngle = basegfx::deg2rad(15.0));
 142
 143 } // end of namespace basegfx::utils
 144
 145 /* vim:set shiftwidth=4 softtabstop=4 expandtab: */