Editing ExtraData (section)

==Creating ExtraData Linedefs ==

Linedef records in ExtraData are associated either with lines which bear the ExtraData Control Line Special (270), or with any linedef in a DOOM-format map which uses a parameterized line special. You can place the 270 special, as well as parameterized special numbers, into the normal "special" field of a line using virtually any map editor. Editors with Eternity-specific configurations should support these specials natively.

Each control linedef (or directly-used parameterized special) specifies its corresponding ExtraData linedef record number as an integer value in its linedef tag field. If your editor does not allow entering arbitrary values up to 32767 into the tag field of linedefs, you will need to use the BOOM command-line editor, CLED. As of the initial writing time of this document, both DETH and Doom Builder support entering arbitrary integer values for the tag field. Check your editor's documentation or user interface to verify if it supports this. 

The flags, sidedefs, textures, and location of the ExtraData control linedef are used normally by the line and cannot be altered from within ExtraData. The true special (if 270 is used) and tag fields of the linedef, along with any extended fields, are specified in the ExtraData record which the control linedef references. 

Any number of linedefs can reference the same ExtraData record. In the event that a control linedef references a non-existent ExtraData record or the ExtraData script for a level is missing, the special and tag of the ExtraData control linedef will both be set to zero.