Defining VIEW Contents Using Id Lists

You can add many elements to a VIEW by displaying the contents of an Id List (IDLI element). The Id List contains a list of the elements to be displayed. Id Lists are contained within Drawing List Libraries (DLLB elements).

Starting at World level, the library part of the database is set up as in the following example:

NEW LIBY /LIB1

NEW DLLB /DLB1

NEW IDLI /ID1

(See the left-hand part of Figure 3:2 in Creating a Drawing, a Sheet and a View)

• Library (LIBY) elements can appear at four positions in the hierarchy (see Appendix A). They are administrative elements used to group together several types of sub-library. The type of sub-library of interest here is the Drawing List Library (DLLB) .

• The DLLB is used to group together Id List (IDLI) elements.

The Id List is constructed by using ADD and REMOVE commands as in the following examples:

ADD /ZONE.PIPES2-1

ADD /ZONE.EQUI2-1

REMOVE /PIPE2-1-12

REM /PUMP2-1-12

ADD and REMOVE may be combined on a single line, for example:

ADD /ZONE1.EQUIP, /ZONE1.PIPES REMOVE /VESS1, BRAN 2 OF /PIPE3

The ADD and REMOVE commands automatically create the Add Entry (ADDE) and Remove Entry (REME) elements shown in Figure 3:2 in Creating a Drawing, a Sheet and a View, also setting those ADDE and REME attributes which refer to (in this example) appropriate elements in the Design database. Other Id Lists may be added or removed in the same way. For example:

NEW IDLI /LIST1

ADD /ZONE1

ADD /LIST2

REM /LIST3

Note: When evaluated individually both /LIST2 and /LIST3 must define a set of design elements which are then added to/removed from /LIST1, respectively. In particular if /LIST3 is being used to remove a number of Branches (say) from /LIST1 then it should be defined as:

ADD /BRAN1, /BRAN2, /BRAN3

and NOT as:

REM /BRAN1, /BRAN2, /BRAN3

If an Id List has Remove entries then the member list order is important. For an entry to be removed it must have been (implicitly) added previously. Hence a Remove Entry should never be the first element in an Id List. Consider the command sequences:

In Sequence 1 the final command removes all branches owned by /PIPE1 - including /PIPE1-1 which has been added by the second command (and implicitly by the first). In Sequence 2 these commands have been reordered so that having removed all branches in /PIPE1 (second command) the required Branch (/PIPE1-1) is added by the final command.

Having created an Id List it can be used to define the contents of a VIEW by setting the VIEW's IDLN attribute directly:

IDLI /ID1

or indirectly:

AUTO /ID1

as described in Defining Views Using the AUTO Commands.

Note: GRIDSYstem and GRIDAXis elements may be added to IDLists but may not be the sole member of the IDList. When drawn their GRIDLNs will be considered to be of infinite length and so will be extended to the VIEW boundary. AUTO commands ignore these elements when calculating the VSCA, THPOS, and SIZE attributes of a VIEW.