include/basegfx/utils/tools.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 <sal/types.h>
  23 #include <basegfx/basegfxdllapi.h>
  24
  25 namespace basegfx
  26 {
  27     class B2DPoint;
  28     class B2DRange;
  29     class B2DPolyPolygon;
  30 }
  31
  32 namespace basegfx::utils
  33 {
  34         /** Expand given parallelogram, such that it extends beyond
  35             bound rect in a given direction.
  36
  37             This method is useful when e.g. generating one-dimensional
  38             gradients, such as linear or axial gradients: those
  39             gradients vary only in one direction, the other has
  40             constant color. Most of the time, those gradients extends
  41             infinitely in the direction with the constant color, but
  42             practically, one always has a limiting bound rect into
  43             which the gradient is painted. The method at hand now
  44             extends a given parallelogram (e.g. the transformed
  45             bounding box of a gradient) virtually into infinity to the
  46             top and to the bottom (i.e. normal to the line io_rLeftTop
  47             io_rRightTop), such that the given rectangle is guaranteed
  48             to be covered in that direction.
  49
  50             @attention There might be some peculiarities with this
  51             method, that might limit its usage to the described
  52             gradients. One of them is the fact that when determining
  53             how far the parallelogram has to be extended to the top or
  54             the bottom, the upper and lower border are assumed to be
  55             infinite lines.
  56
  57             @param io_rLeftTop
  58             Left, top edge of the parallelogramm. Note that this need
  59             not be the left, top edge geometrically, it's just used
  60             when determining the extension direction. Thus, it's
  61             perfectly legal to affine-transform a rectangle, and given
  62             the transformed point here. On method return, this
  63             parameter will contain the adapted output.
  64
  65             @param io_rLeftBottom
  66             Left, bottom edge of the parallelogramm. Note that this need
  67             not be the left, bottom edge geometrically, it's just used
  68             when determining the extension direction. Thus, it's
  69             perfectly legal to affine-transform a rectangle, and given
  70             the transformed point here. On method return, this
  71             parameter will contain the adapted output.
  72
  73             @param io_rRightTop
  74             Right, top edge of the parallelogramm. Note that this need
  75             not be the right, top edge geometrically, it's just used
  76             when determining the extension direction. Thus, it's
  77             perfectly legal to affine-transform a rectangle, and given
  78             the transformed point here. On method return, this
  79             parameter will contain the adapted output.
  80
  81             @param io_rRightBottom
  82             Right, bottom edge of the parallelogramm. Note that this need
  83             not be the right, bottom edge geometrically, it's just used
  84             when determining the extension direction. Thus, it's
  85             perfectly legal to affine-transform a rectangle, and given
  86             the transformed point here. On method return, this
  87             parameter will contain the adapted output.
  88
  89             @param rFitTarget
  90             The rectangle to fit the parallelogram into.
  91          */
  92         BASEGFX_DLLPUBLIC void infiniteLineFromParallelogram( ::basegfx::B2DPoint&      io_rLeftTop,
  93                                             ::basegfx::B2DPoint&        io_rLeftBottom,
  94                                             ::basegfx::B2DPoint&        io_rRightTop,
  95                                             ::basegfx::B2DPoint&        io_rRightBottom,
  96                                             const ::basegfx::B2DRange&  rFitTarget  );
  97
  98         /** Creates polypolygon with the given number as seven-segment
  99             digits
 100
 101             @param fVal
 102             Value to convert
 103
 104             @param nTotalDigits
 105             Total number of digits to display. If less is needed for
 106             given number, fill space with blanks.
 107
 108             @param nDecPlaces
 109             Decimal places to show. When 0, display as integer. When
 110             negative, fill given number of before-the-decimal point
 111             with zero.
 112
 113             @param bLitSegments
 114             When true, return a polygon containing the segments that
 115             are 'lit' for the given number. Return un-lit segments
 116             otherwise.
 117          */
 118         BASEGFX_DLLPUBLIC B2DPolyPolygon number2PolyPolygon(double    fVal,
 119                                                             sal_Int32 nTotalDigits,
 120                                                             sal_Int32 nDecPlaces,
 121                                                             bool      bLitSegments=true);
 122 }
 123
 124 /* vim:set shiftwidth=4 softtabstop=4 expandtab: */