Naming convention.

name-space		internal	external
==========		========	========
function		mobject__xxx	mobject_xxx
symbol variable		Mobject__xxx	Mobject_xxx
other variable		mobject__xxx	mobject_xxx
constant macro			MOBJECT_XXX
other macro			MOBJECT_XXX
type				MObject[Xxx]

A structure is named as MXxxxx and is `typedef'ed with the same name.
Ex: typedef struct MFace MFace

In comments, a structure member is denoted simply as `<member_name>',
but a member of a specific structure is denoted as
`MStruct->member_name'.  If the member itself is a structure (or a
pointer to a structure) and has a sub-member, the sub-member is
denoted as:
	`<member_name.sub_name>'
	or `<member_name->sub_name>'
	or `MStruct->member_name.subname'
	or `MStruct->member_name->subname'