As discussed in the introduction, Objects are represented by O tags. Contained in these O tags are attributes that describe or provide additional information regarding the object.
<O N="Object1" T="Surface" Extends="Surface1" />
<O N="Object2" T="Surface" Extends="Surface1" Y="Object1.h/2" Z="w/2" RX="PI" />
NOTE:
Object1 and Object2 each extends (inherits from) Surface1. This means that each of them implicitly has the same parameters and sub objects of Surface1. If a parameter that is inherited from Surface1 also exists either in Object1 or Object2, then Object1's or Object2's parameter overrides (Surface1's parameter is ignored).
In the syntax above, Object2's Y-axis translation is attributed to Object1.h/2. This syntax will make Object2 use Object1's h parameter specifically. If the object is not specified, it will use any h parameter it finds in the project, particularly the one closest to the expression using it.