gseara
Purpose
Draws an elliptical arc between two angles.
C Syntax
int gseara_ (cx, cy, ma, mi, ang, sa, ea)
int *cx, *cy, *ma, *mi, *ang, *sa, *ea;
FORTRAN Syntax
INTEGER function gseara (cx, cy, ma, mi, ang, sa, ea)
INTEGER cx, cy, ma, mi, ang, sa, ea
Pascal Syntax
FUNCTION gseara_ (
VAR cx, cy, ma, mi, ang, sa, ea : INTEGER
): INTEGER [PUBLIC|;
Description
The gseara subroutine draws a counterclockwise elliptical
arc of the specified axes and angle from the beginning
point defined by an angle specification to the ending
point defined by an angle specification. 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
gseara 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.
sa Defines the angle of the starting point of the
elliptical arc, measured counterclockwise from
the major axis. The angle is expressed in
tenths of degrees, from 0 to 3600.
ea Defines the angle of the ending point of the
elliptical arc, measured counterclockwise from
the major axis. The angle is expressed in
tenths of degrees, from 0 to 3600.
If the beginning and ending points are identical, 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.