Object Object Type Property Symbol Line Polyline Polygon Object Components Node Intrinsic End Properties Edge Boundary Interior       Rotation       MBR   Direction   Geometric Centroid Derived Shifted MBR Centroid Properties Visual Centroid       Principal Axes Side All   Aspect All   Applied Properties Style symbol style line style line style region style

For a polyline aspect and side are determined at the segment containing the centroid. Node means any node defined for an object. For a polygon, end is any single node on the boundary. Whilst a polygon has a defined start node, its definition is arbitrary, likely to change with basic manipulation and thus of dubious value. An edge match includes the nodes defining that edge. The centroid of a region may be outside the region boundary. (eg. U-shape) A point object has all sides and aspects. A region object has no sides or aspect definition. The end segments of linear objects may be considered as extending to the limit of data bounds for the purposes of side and aspect. The actual extent is usually determined by a buffering method. Style attributes are only mentioned here because they can change the apparent (visual) properties of objects. (eg. hide the boundary of a polygon). Object collection properties are a superset of object properties. eg. A multi-section polyline will contain multiple pairs of ends. A region is a collection of polygons. Principal Axes: Ixx is the moment of inertia (2nd moment of area) about the x-axis Iyy is the moment about Y Ixy is the product of inertia I1,I2 are principal moments of inertia. Theta is the angle of the principal axes to the X axis. References: http://www.infogoaround.org/JBook/Inertia.html http://web.umr.edu/~oci/Topic12/frame12-1.html

Spatial Relationships

The SQL method compares object pairs in the following manner:

Spatial Operator	Description	As defined by
Intersects	The boundary or interior of the objects intersect	MapInfo
Within	The centroid of the first object is within the boundary of the second object	MapInfo
Entirely within	The boundary of the first object is entirely within the boundary of the second object.	MapInfo
Contains	The boundary of the first object contains the centroid of the second object	MapInfo
Contains entire	The boundary of the first object contains the boundary of the second object	MapInfo
Touch	A node on one object intersects the boundary of the second object	spatialSQL
Touch Ends	One or both ends of the objects touch. Regions touch at a single node	spatialSQL
Touch Edge	One or more edges of the objects touch along the full length of one edge.	spatialSQL
Disjoint	Boundary and interior of the objects dont intersect	spatialSQL
Equals Scalar	The boundary of the objects have identical geometry but in either node order.	spatialSQL
Equals	The boundary of the objects have identical geometry and the direction of the objects are identical.	spatialSQL