Layer Purpose Definitions

The Layer Purpose Definitions form is displayed when you select the Layer Purpose Definitions button on the Draft System Defaults form.

The scrollable list shows all currently defined layer defaults. The highlighted layer is the one that will be updated by any new settings that you enter.

All layers have a PURP attribute which is set to a four character keyword which identifies the purpose for which that layer is intended to be used. Layer purposes cannot be duplicated under any one owning View. The Layer Purpose box on the form allows you to specify the purpose as a three-character string (the fourth character is added automatically when setting PURP so that multiple layers of a given type can be created under a single View).

For example, if you have defined a layer with its purpose defined as DIM and a user decides to have three dimension layers in each View for, say, steelwork (STLDIM), equipment (EQUDIM) and piping (PIPDIM), then the View contents might be as follows:

where the fourth character of the PURP (A, B or C) distinguishes the individual DIM layers.

Note: The purpose keyword TAG is reserved for autotagging layers. This is a requirement of the application (see Chapter 14) and must always be defined in the layer defaults. If it is omitted, a TAG layer purpose definition will be appended automatically during default initialization. The TAG layer purpose definition cannot be deleted.

The Setup File box is used to specify the macro file that will be executed to set the layer attributes after a layer has been created. Default macro files are supplied with the product. For example, DRA-GEN-DEFLAY defines the default attribute values for layers. This ensures that all users create layer annotation to a common standard.

You can copy and modify these macro files to meet your company and/or project standards. You can also create new files for other purpose types of your own definition.

The Attribute Group check boxes (Dim, Note, Text, Lab and Symb) allow you to specify which attribute types will be displayed on the Layer Attributes form. The combination which applies to each of the currently defined layers is shown by the + (selected) and - (unselected) codes in the scrollable list.

• To change these, turn the attributes on and off as required and then click the Apply button.