remove_names_from_set(3G)

NAME

remove_names_from_set, remove_all_names_from_set − remove names from the current name set

SYNOPSIS

C Syntax:

void remove_names_from_set ( fildes, count, names )
int fildes, count, names[];

void remove_all_names_from_set ( fildes )
int fildes;

FORTRAN77 Syntax:

subroutine remove_names_from_set ( fildes, count, names )
integer*4 fildes, count, names ( count )

subroutine remove_all_names_from_set ( fildes )
integer*4 fildes

Pascal Syntax:

procedure remove_names_from_set ( fildes, count: integer;
var names[lo..hi:integer] of integer );

procedure remove_all_names_from_set ( fildes:integer );

DESCRIPTION

Input Parameters

fildes Integer file descriptor returned by gopen when an I/O path to a graphics device is opened.

count Number of integers in the names array that represent bit strings of names.

names Array of integer bit strings representing names to be added to the current name set.

Discussion

Remove_names_from_set removes some of the names from the current name set. Remove_all_names_from_set removes all names from the current name set. Names are added to the current name set by add_names_to_set(3G). The use of name sets allows the programmer to divide a segment hierarchy into logical sections, the visibility, pickability, and highlighting of which may be controlled by the invisibility, pick, and highlighting filters (see set_invisibility_filter(3G), set_highlighting_filter(3G), and set_pick_filter(3G)).

Each bit in each integer represents a unique name. Assuming integers are 32 bits, this means that 32 names may be represented with one integer, 64 names with two integers, 96 names with three, etc. The maximum number of names allowed is limited only by available memory.

When remove_names_from_set, remove_all_names_from_set, or one of their respective elements is executed, the specified names are removed (mathematical set difference) from the current name set. This changes the current name set, which (in conjunction with the current filters) controls how display list traversal processes subsequent elements. See the manual pages for each filter for descriptions of their effects.

Remove_all_names_from_set is normally used to clear the current nameset before a traversal to remove any names remaining from the previous traversal.

EXAMPLE

For an example of how to use remove_names_from_set, see add_names_to_set(3G).

ERRORS

1 Graphics device is not initialized for this operation.

6 Invalid parameter value − count less than 0.

DEFAULTS

When a graphics device is gopen’ed, the current name set of the display list of that device is empty.

Museum

Related Articles