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⇒ gsearc(3) — AIX/RT 2.2.1

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gsearc

Purpose

     Draws an elliptical arc between two points.

C Syntax

     int gsearc_ (cx, cy, ma, mi, ang, bx, by, ex, ey, rot)

     int *cx, *cy, *ma, *mi, *ang, *bx, *by, *ex, *ey, *rot;

FORTRAN Syntax

     INTEGER function gsearc (cx, cy, ma, mi, ang, bx, by, ex, ey, rot)

     INTEGER cx, cy, ma, mi, ang, bx, by, ex, ey, rot

Pascal Syntax

     FUNCTION gsearc_ (

     VAR cx, cy, ma, mi, ang, bx, by, ex, ey, rot : INTEGER
     ): INTEGER [PUBLIC|;

Description

     The gsearc subroutine draws a counterclockwise elliptical
     arc of  the specified axes  and angle from  the beginning
     point to  the ending  point.  The  axes are  expressed in
     number of pixels.

     The angle specifications are  given in tenths of degrees,
     from  0 to  3600.  Values  outside this  range cause  the
     gsearc subroutine to fail.

     The relevant attributes are:

     o   Color map
     o   Plane mask
     o   Line color index
     o   Line style
     o   Logical operation.

     Parameters

     cx, cy    Define  the coordinates  of the  center of  the
               ellipse.

               For displays, the center is restricted to -2048
               to 2048.

               For  printers  and   plotters,  the  center  is
               restricted to screen coordinates.

     ma, mi    Define  half of  the non-zero  major and  minor
               axes of the ellipse.

     ang       Defines the  angle between  the major  axis and
               the x-axis.  If ang is  zero, the major axis is
               on  the x-axis  and the  minor axis  is on  the
               y-axis.  The  angle is  expressed in  tenths of
               degrees, from 0 to 3600.

     bx, by    Define the  coordinates of the  beginning point
               on the ellipse.

     ex, ey    Define the  coordinates of the ending  point on
               the ellipse.

     rot       Specifies whether the  application must perform
               rotational  transformation.   Possible  setting
               are:

               0     The  coordinates  of  the  beginning  and
                     ending points  passed by  the application
                     correspond  to an  arc  of an  orthogonal
                     ellipse.  No rotational transformation is
                     performed, thus improving performance.

               1     The  beginning  and   ending  points  are
                     transformed by the application and lie on
                     the off-axis ellipse.

               All other  values are reserved and  must not be
               used,   as  they   may  produce   unpredictable
               results.

     If the beginning and ending points are identical, regard-
     less of  whether or not they  are on the ellipse,  a full
     ellipse is drawn.

Return Value

     GS_SUCC   Successful.
     GS_CORD   Invalid coordinate.
     GS_ELMM   Invalid major or minor axis.
     GS_INAC   Virtual terminal inactive.
     GS_ANGL   Invalid angle.
     GS_NMEM   Insufficient resources.
     GS_AEND   Invalid end point.
     GS_ASTR   Invalid start point.

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