POLYLINE SET 3

PXPLS3

CALL SEQUENCE

CALL PXPLS3 (NLINES, IENDPT, XA, YA, ZA)

INPUT PARAMETERS

INTEGER

NLINES Number of polylines

INTEGER IENDPT(NLINES)

End vertex index for each polyline

REAL XA(_*)

X coordinates of each vertex in MC

REAL YA(_*)

Y coordinates of each vertex in MC

REAL ZA(_*)

Z coordinates of each vertex in MC

EFFECT

Depending on the edit mode, a Polyline Set 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.

At structure traversal time, each polyline in the set is rendered by sequentially connecting the points with straight lines, starting from the first point and ending with the last point of the polyline. The polylines are rendered using the current polyline attributes.

End Vertex Index For Each Polyline specifies the position within the XA, YA, and ZA arrays of the last vertex of each boundary.

Polyline attributes and their corresponding ASFs (aspect source flags) are:

Polyline attributes are taken from:

• the PHIGS state list if the corresponding ASFs are Individual, and the structure is non-retained
• the traversal state list if the corresponding ASFs are Individual, and the structure is retained
• the workstation bundle table if the corresponding ASFs are Bundled.

The polyline bundle index specifies which workstation polyline bundle is used.

For further information on specifying polyline attributes, see the references.

Performance Considerations

Polyline sets are useful because GPHIGS can process them more quickly than the equivalent number of separate polylines. They are stored in the structure database more quickly, and they are rendered more quickly. If you have several small polylines which all have the same attributes, it is more efficient to specify them as a polyline set.

Degenerate Polylines and Polyline Sets

A polyline set with zero or fewer polylines is inserted into the open structure but not displayed. A polyline with fewer than two vertices is not displayed.

ERRORS

5

Ignoring function, function requires either the state STNOP or the state STOP.

SEE ALSO

Line type, see PSLN

Line width scale factor, see PSLWSC

Polyline, see PPL, PPL3

Polyline set, see PPLS3C, PXPLS

Polyline bundle definition, see PSPLP, PSPLR, PSPLRP

Polyline bundle index, see PSPLI

Polyline color, see PSPLC, PSPLCI

Polyline extension, see PXARC

Inquire individual ASF, see PQIASF

Inquire line type, see PQLN

Inquire line width scale factor, see PQLWSC

Inquire polyline bundle definition, see PQPLP, PQPLR, PQPLRP

Inquire polyline bundle index, see PQPLI, PQEPLI

Inquire polyline color index, see PQPLCI

Inquire polyline facilities, see PQPLF