GDP ELLIPSE 3

PXELL3

CALL SEQUENCE

CALL PXELL3	(ITYPE, XPOS, YPOS, ZPOS, XMINOR, YMINOR, ZMINOR, XMAJOR, YMAJOR, ZMAJOR, DEVIAT)

INPUT PARAMETERS

INTEGER ITYPE

Primitive type

1	PXPL	polyline
2	PXFA	fill area
3	PXFAS	fill area set
4	PXPM	polymarker

REAL XPOS

X coordinate of the center in MC

REAL YPOS

Y coordinate of the center in MC

REAL ZPOS

Z coordinate of the center in MC

REAL XMINOR

Minor axis X component in MC

REAL YMINOR

Minor axis Y component in MC

REAL ZMINOR

Minor axis Z component in MC

REAL XMAJOR

Major axis X component in MC

REAL YMAJOR

Major axis Y component in MC

REAL ZMAJOR

Major axis Z component in MC

REAL DEVIAT

Chordal deviation in millimeter

EFFECT

Depending on the edit mode, a GDP Ellipse 3 element is inserted into the open structure after the current element or replaces the current element. The newly inserted element becomes the current element.

As specified by Primitive Type, the new element will be rendered as a polyline, fill area, fill area set, or polymarker, using the current attributes for that element type.

If the specified major and minor axes are not perpendicular, GPHIGS will generate an error, and the function will be ignored.

Chordal deviation refers to the maximum distance between the desired curve and the midpoint of a segment making up the polyline approximation of the curve. Thus, the smaller the chordal deviation, the smoother the curve. Since the smoothness of a curve is ultimately limited by the resolution of the workstation display, specifying a chordal deviation which is smaller than the workstation pixel size will not improve the display, and will slow GPHIGS considerably, because it is forced to calculate and draw an excessive number of vertices.

ERRORS

1

Ignoring function, function requires state PHOP.

5

Ignoring function, function requires state STNOP or state STOP.

SEE ALSO

GDP circle, see PXCRCL

GDP ellipse, see PXELL

GDP elliptical arc, see PXEAR, PXEAR3