qpgraph.hlp (Topic list)
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_Arc... Procedures
  Summary Details Example                                   Back
 
  Arguments
 
    x1, y1        Upper-left corner of bounding rectangle
 
    x2, y2        Lower-right corner of bounding rectangle
 
    x3, y3        Arc begins at the intersection with a line which
                  starts at the rectangle's center and passes through
                  this point
 
    x4, y4        Arc ends at the intersection with a line which starts
                  at the rectangle's center and passes through this
                  point
 
    wxy1, wxy2    Window coordinates of upper-left and lower-right
                  corners of bounding rectangle
 
    wxy3, wxy4    Arc begins and ends at the intersection with lines
                  which start at the rectangle's center and pass
                  through these points
 
  Description
 
    The _Arc routines draw an arc given the bounding rectangle and
    beginning and ending line endpoints in viewport coordinates.
    The center of the arc is the center of the bounding rectangle
    defined by points (x1,y1) and (x2,y2). The arc starts where it
    intersects an imaginary line extending from the center of the arc
    through (x3,y3). It is drawn counterclockwise about the center of
    the arc, ending where it intersects an imaginary line extending
    from the center of the arc through (x4,y4).
 
    _Arc_wxy uses the window coordinate system. The center of the
    arc is the center of the bounding rectangle defined by window
    coordinates wxy1 and wxy2. The arc starts where it intersects
    an imaginary line extending from the center of the rectangle
    and passing though the points wxy3. Then the arc is drawn
    counterclockwise and ends where it intersects an imaginary line
    extending from the center of the arc through wxy4.
 
    In both cases, the arc is drawn using the current color. Since an
    arc does not define a closed area, it is not filled.
 
  _GrStatus Returns
 
    _GrClipped, _GrInvalidParameter, _GrNoOutput, _GrNotInProperMode