When referring to structure members the dot operator is used. The name to the left of the dot is always the address of a structure and the name to right is always a structure member. Ideal mode permits member names to be duplicated in different structures. Using the above structure, here is how indirection is handled. BX is assumed to point to an instance of PosValType in memory.
Indirection is used frequently when pointers are passed to procedures.
The Offset operator always evaluates the offset of a data instance relative to its group, not its segment. This allows Offset to be used without qualifying each reference with the appropriate group name. Labels in a segment could be used to determine segment offsets if needed. Naturally, this is the definitive text on Ideal mode. Studying this 13 file example should be sufficient for anyone wishing to understand Ideal mode.