Element: entity.valid
Element: entity.validnumeric
Whether the entity has valid geometry. This has a value 1 for valid, 0 for invalid. Although an entity may have been created succesfully, subsequent changes to its properties may render it invalid when it comes to be drawn, or when other operations are performed on it.
The following entities can be considered "invalid":
A cell entity whose image file cannot be accessed.
A polygon entity which has crossovers or slithers. This is determined at creation or modification time by a validation check using the then-current value of the system identifier polygon_validation.
A gtext or glabel entity which refers to a text file which cannot be accessed.
An instance entity whose entity file cannot be accessed.
A compound entity, if one of its child entities is invalid.
All other entities are considered to be "valid".
The reason for any invalidity can be checked by examination of the
entity.invalidity attribute.
This element is read-only and cannot be changed directly.