An application sub-window menu is laid out in a rectangular grid. It is possible, say in a spreadsheet application, to label rows and columns. These labels are known as Indices.

The format of the definition of indices is remarkably similar to that for the actual items in an application sub-window menu and similarly, the index item lists consist of a set of list entries, one for each column in a row (or each row in a column.)

Each index entry contains the item number for the object, the object type (text, sprite etc.), the justification (left, right or centre, top, bottom or centre) and a pointer to the actual object to be displayed in that particular index.

There are no action routines or item numbers in an index entry list. These are set to zero and minus 1 respectively.

Name      Off Size      Description
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wdm_xjst  $00  Byte  Object x justification rule.
wdm_yjst  $01  Byte  Object y justification rule.
wdm_type  $02  Byte  Object type: 0 = text, 
                                  2 = sprite, 
                                  4 = blob, 
                                  6 = pattern.
wdm_skey  $03  Byte  Item selection keystroke. (Uppercased)
wdm_pobj  $04  Word  Pointer to item object.
wdm_item  $06  Word  -1.
wdm_pact  $08  Word  Zero.
wdm.olen  $0A  n/a   Menu object / index list entry length.
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