.layer file

Layer definition file. In AutoCAD Map 3D, a file that saves all of the information required to recreate a layer, that is, the references to the source data and the styles that have been applied to it.

adjacent sheet block

An annotation block used to indicate adjacent tiles.


Text and graphics used to label objects in a drawing dynamically.

annotation definitions

Specially created blocks containing attributes with Map expression assigned to the attribute properties. Used with drawing data.


Data that depicts the final installed configuration (physical or functional). As-built data incorporates any field markups on the original construction drawings.


Data that depicts the original plan for construction or installation, for example, the design for a new electric service or a new pipe installation.


Direction of ground slope.

attributes or attribute data

Tabular data that describes the characteristics of feature or drawing objects, for example, the number of lanes and pavement-type belonging to a road. For features, attributes can be stored with the geometry, or stored in a database and joined to feature data. For drawing objects, attributes are stored in a database and linked to selected drawing objects. See also property, external data and object data.

auto-generated field (metadata)

A type of field in the Metadata feature, the value of which is derived from the data source, and populated automatically by AutoCAD Map 3D. Metadata auto-generation is triggered by selecting the resource in the Metadata Viewer. See also: forced-update field

AutoCAD layer

A layer in AutoCAD. An AutoCAD layer differs from a map layer you create in Display Manager. See also layer, drawing layer, feature layer, or surface layer.

Autodesk Design Review

The free viewer and editor for the DWF file format (formerly DWF Viewer).


A clockwise angle measured from a reference meridian. Also known as north azimuth. It can range from 0 to 360 degrees. A negative azimuth is converted to a clockwise value.


An angle measured from North or South, whichever is nearest, with the added designation of East or West. The angle is always less than 90 degrees (PI/2 radians or 100 grads) and is usually referenced by a quadrant number.

best route analysis

Calculates the shortest path or optimal route from a start point in a drawing, one or more intermediate points, and back to the start point. For example, the best route to follow on a street map when visiting multiple customer sites.


In AutoCAD or AutoCAD Map 3D, compound objects that have been saved for reuse in the drawing or in multiple drawings, for example, a North arrow. In MapGuide Studio, blocks are converted into symbols when they are loaded. See also symbol.


A zone of a specific radius created around a selected feature. Used to select features within a specific distance of another feature. In AutoCAD Map 3D, you can define buffers for drawing topologies and for features, but you define them differently.

buffer fence

A fence, or line, at a specified distance from a center line. Used to define a selection boundary.


For contours that contain curves, the bulge value is a maximum mid-ordinate distance along a polyline curve. If the mid-ordinate distance is longer than specified, then points are added to better define the shape of the curve.

The bulge factor can add more vertices to a polyline curve, making it appear more curve-like. The smaller the value, the more vertices are added.

Cartesian coordinate system

A global coordinate system defined using three perpendicular axes (X, Y, and Z) to specify locations in three-dimensional space. Compare with spherical coordinate system.

cartographic coordinate system

A global coordinate system that is referenced directly to an ellipsoid. Compare with geodetic coordinate system.


Points or blocks that are part of a polygon in a drawing topology. The centroid holds information about the area and perimeter of the polygon.

chained join

An advanced type of join, where two or more secondary tables are joined to a primary table in a chain-like fashion, that is primary linked to secondary linked to another secondary, and so on.


The action of locking features in a data store before editing them. See also explicit checkout, implicit checkout.

classified DWG

An AutoCAD Map 3D DWG (drawing) file that contains object classes, and uses them to represent real-world objects in the drawing. A DWG file that contains object class definitions, but does not have any objects to which these definitions are applied, is not considered a classified DWG.

clustered nodes

Nodes within a specified tolerance of one another.


Short for Coordinate Geometry. COGO inquiry commands extract geometric information from drawing objects such as lines, curves, closed polylines, and polygons. This information is useful if you want to verify the accuracy of your data, or send the data to the field. Inquiry commands are specific to drawing objects. They do not work on features.


A specific category of information in a table, such as Address or Diameter, also called a FGDC CSDGM Standard. See also table.

compound element (metadata)

A group of data elements in the FGDC CSDGM Standard. A compound element can consist of individual data elements, other compound elements, or both.

conformal projection, conformality

Conformal projections maintain local angles. A map projection is conformal when the scale is the same in every direction at any point. Meridians and parallels intersect at right angles; the shape of small areas and angles with very short sides are preserved. Most larger area sizes are distorted.

conic projection

A map projection in which the surface of the Earth is drawn as it would appear if projected on a cone wrapped around the earth. The Lambert Conformal Conic is often used for maps of the continental United States, France, and other countries.


In a database, a restriction specified for a certain feature class, which is validated when a new feature is added to that class. For example, a "minor road" feature class may have a constraint that specifies that the speed attribute must always be 25, 30, or 50 miles per hour.

continuous data

Data that can fall anywhere in a broad range. When creating a theme, continuous data is usually organized into smaller ranges that show data trends. For example, property value is continuous data that can be placed into the ranges 0 to $50,000, $50,000 to $100,000, and over $100,000, with each range displayed in a different color. Compare with discrete data.

contour lines

A line that connects points of the same elevation or value relative to a specified reference datum. The lines can help you determine the elevation at a specific location on a surface, help clarify and analyze the 3D surface terrain, and help with things like navigation.

control points

Locations with established latitude and longitude, and often elevation, used for accuracy and precise location of maps. A system of geodetic control points covers the entire United States. Similar systems exist for all countries, such as Bench Marks and Trigonometry Points in the United Kingdom. See also monuments, geodetic coordinate system.

coordinate geometry commands


coordinate system

The user ID and password required to connect to a database.

cylindrical projection

A map projection, in which the surface of the Earth is drawn as it would appear if projected on a cylinder wrapped around the earth in a north-south direction. Compare with transverse cylindrical projection. See also Mercator projection and conic projection.


A link or line, one end of which lacks a connection to another link or node.

Data Connect

The window you use to connect a geospatial data store to your map. You specify each feature class from that data store to add to your map.

data element (metadata)

A single piece of data that can be entered directly, as a value in a field. In the Metadata feature, single data elements are expressed as fields to be completed with values defined in the FGDC CSDGM Standard. See also: compound element (metadata).

data provider

A recognized FDO feature source provider, used to connect to geospatial data.

data source

A UDL (universal data link) file that points to a collection of data and provides information on how to access the data.

data store

In FDO, a collection of feature classes contained in a single storage location. The data store consists of an integrated set of objects, which are modeled by classes or feature classes defined within one or more schemas. Data stores can be either file-based, such as SDF, or a database, such as Oracle Spatial. See also FDO provider and feature class.

Data Table

In AutoCAD Map 3D, a grid based on FDO data, in which you can view and edit attributes of selected map features, perform searches, and work with selection sets.

Data View

In AutoCAD Map 3D, the grid in which you can view and edit external database tables that are linked to drawing objects.

database query

A set of conditions for specifying the selection of records from a database. External database queries, also called views, are created using your database software and can be run from the Map Explorer tab of the Task Pane. See also map query.


A mathematical model that provides a smooth approximation of the earths surface. Each datum includes both an ellipsoid, which specifies the size and shape of the earth, and a base point for latitude and longitude. If two maps use different datums, points on the map may not line up. Also called a geodetic coordinate system.


Digital Elevation Model. A file that contains a representation of surface terrain. The surface is stored as a grid in which each cell can have any one of several different meanings, such as elevation, color, density, and so on.


To convert existing data from paper maps, aerial photos, or raster images into digital form by tracing the maps on a digitizer. Object locations are recorded as X,Y coordinates.

discrete data

Data that falls into explicit categories. For a feature layer that uses a theme, each value is displayed differently. For example, an agricultural thematic map might show each crop in a different color. Compare with continuous data.

display information

A description of the appearance of a drawing object: includes items such as layer, color, hatch pattern, and line type.

Display Manager

A view of the Task Pane that shows each Display Manager layer in your current display map, and has commands for styling and managing those layers. To view Display Manager, select its tab in the Task Pane.

Display Manager layer

A set of objects in Display Manager. The set could be all the objects on a layer or in a feature class, or objects that share a certain property. Each layer can be styled or themed individually.

display map

A set of map presentations, consisting of Display Manager layers, that can be stored in a DWG file. See Display Manager layer.

display properties

To remove the boundaries that exist between polygons sharing a specific attribute.


To use a pattern of solid dots to simulate more colors than are available when displaying images.

domain (metadata)

In the Metadata feature, the domain refers to element values that are defined as valid within the FGDC CSDGM Standard. A domain can be a list of pre-defined values in a menu, a range of numbers, free-form text, or any other type of value that can be assigned to a given field.

dot variable

Variable that refers to an object property. It consists of a period (.) followed by the variable name for that property. Dot variables can be entered in expressions used for building a template file for Report mode queries and for property alteration. See also query and expression.


The process of overlaying feature or a raster image on a surface so that the features or the image reflect the underlying terrain.


The process of overlaying a set of feature or a raster image on a surface so that the features or the image reflect the underlying terrain.

drawing layer

A layer in Display Manager that contains drawing objects from a DWG file. See also AutoCAD layer, feature layer, layer, surface layer.

drawing layerdrawing objectdrawing source

A layer in Display Manager that contains drawing objects from a DWG file. See also AutoCAD layer, drawing layer, feature layer, and surface layer.

Objects that exist in a drawing (DWG) file or come from an attached drawing. Compare to features.

In AutoCAD Map 3D, a drawing source is a drawing (DWG) file and also its associated information, such as attached drawing files, drawing-based feature classes, linked template data, and topologies.

drawing objects

Objects that exist in a drawing file (DWG) or come from an attached drawing. Compare to feature.

drawing set

The set of source drawings attached to a drawing. See source drawing.

drawing source

In AutoCAD Map 3D, a drawing source is a drawing (DWG) file and also its associated information, such as attached drawing files, drawing-based feature classes, linked template data, and topologies. Compare with feature source.

drive alias

The mechanism that points to the folder where attached DWG files are stored.

drive alias

In AutoCAD Map 3D, the mechanism that points to the folder where attached DWG files are stored.


Digital Terrain Elevation Data.

duplicate objects

Objects that share the same start and end points. Object types that can be considered duplicate include linear objects, points, blocks, text, and mtext.


An Autodesk file format for sharing 2D, 3D, and spatially enabled design data. DWF files are easy to publish and view on the web. See also georeferenced DWF, Autodesk Design Review.


Drawing file. The Autodesk file format for storing 2D, 3D, and spatially enabled design data.

edge matching

A DWG cleanup function available in AutoCAD Map 3D that allows for distortion between adjacent maps, and produces a true match of drawing objects at the edges of maps.


When users decide to lock objects in Oracle Spatial, those objects are immediately locked. Edits of locked objects are put into an EditSet. You can then update the database, which updates the locked records with the contents of the EditSet.

element (Oracle Spatial database)

The basic building block of an Oracle Spatial geometry (Oracle Spatial database). The supported spatial element types are points, line strings, and polygons. For example, elements might model water wells (point clusters), roads (line strings), and county boundaries (polygons).


The vertical distance from a datum to a point or object on the surface of the Earth. The datum is generally considered to be at sea level. Equivalent to the Z coordinate in an XYZ coordinate system.


An approximation of the shape of the Earth that does not account for variations caused by the nonuniform density of the earth. Synonymous with spheroid. See also geoid.

equal area

A map projection in which every part, as well as the whole, has the same area as the corresponding part on the earth, at the same reduced scale. No flat map can be equal area and represent true shape.

equidistant projections

Projections showing true distances only from the center of the projection or along a special set of lines. No flat map can be both equidistant and equal area.

explicit checkout

The action of checking out features using the Check Out Features command. See also checkout, implicit checkout.


An automatic calculation used to specify values for URL, tooltip, and feature labels. For example, you might create a text expression that specifies a state name and population for a label. To express the population in millions, you might apply a number expression that divides the population value by 1,000,000.

expression evaluator

The mechanism that analyzes the statement you enter in the Expression box in the Output Report Options dialog box or the Property Alteration dialog box.

external data

Attribute data linked to a drawing object but contained in a database apart from the drawing file. See also attributes or attribute data and object data.


Feature Data Objects (FDO) data access technology. An Autodesk software standard and general purpose API for accessing features and geospatial data regardless of the underlying data store. See also feature, feature class.

FDO provider

An implementation of the FDO API that provides access to data in a particular data store, such as an Oracle or ArcSDE database, or to a file-based data store, such as SDF or SHP.


An abstraction of a natural or man-made real world object. A spatial feature has one or more geometric properties. For example, a road feature might be represented by a line, and a hydrant might be represented by a point. A non-spatial feature does not have geometry, but can be related to a spatial feature that does. For example, a road feature may contain a sidewalk feature that is defined as not containing any geometry. In AutoCAD Map 3D, features are accessed and added to maps using Data Connect (FDO). See also attributes or attribute data. Compare to drawing objects.

feature class

For feature data, a schema element that describes a type of real-world object. It includes a class name and property definitions. Commonly used to refer to a set of features of a particular class, for example, the feature class "roads" or the feature class "hydrants." See also FDO, property, schema.

Feature Data Objects

See FDO.

feature layer

A layer in Display Manager containing feature from a feature source such as SDF, ESRI SHP, or ArcSDE. Feature layers are brought in using Data Connect. See also AutoCAD layer, layer, drawing layer, or surface layer.

feature source

In AutoCAD Map 3D, any source of feature data that has been connected by means of FDO. In MapGuide Studio, one of the two types of resources created either by loading file-based data or by connecting to a spatial database. Feature sources are stored in the repository either in SDF 3 format or as database connections and contain raw geometry only. Compare with drawing source.


Content Standard for Digital Geospatial Metadata. A standard XML schema for publishing and sharing GIS metadata, released by the United States Federal Geographic Data Committee (FGDC) in 1998. The schema is comprised of seven major sections, each of which contains several individual data elements and compound elements. Depending upon the nature of the GIS data, each section, element, and compound element is mandatory, optional, or conditional (mandatory if applicable).


A specific category of information in a data file, such as Address or Diameter. Also called a column. See also table.

filtered record

A record that matches the conditions of an SQL filter or spatial filter and is therefore available for selection.

flood trace

For a network topology, a trace that begins at a specified point and traces out in all directions for a specified distance or resistance.

forced-update field

A type of auto-generated field (metadata) in the Metadata feature, the value of which is required to be derived from the data source within a GIS resource (metadata), according to the rules of the FGDC CSDGM Standard. Forced-update fields are updated each time metadata is updated.


A method of reducing the number of vertices in the source data by a specific percentage.

geodetic coordinate system

A coordinate system that is referenced directly to a datum. Compare with cartographic coordinate system.

geographic analysis

Analytical techniques that identify existing conditions of a geographic location, a spatial area, or a linear network, and predict the effects of certain future events on these features.

geographic data

Information about geographic features. See feature.


An ellipsoid with a highly irregular surface used to describe the shape of the earth. See also ellipsoid.

geometry (Oracle Spatial database)

The representation of a spatial feature, modeled as an ordered set of primitive elements. See element (Oracle Spatial database).

geometry mapping

The process of transforming the geometry elements of AutoCAD Map 3D objects to Oracle Spatial geometry, and transforming the geometry elements of the records back to AutoCAD Map 3D objects.

georeferenced DWF

A DWF file published by AutoCAD Map 3D or AutoCAD Civil 3D 2008 that contains a global coordinate system and defined latitude and longitude coordinates based on the WGS84 datum. See also DWF, Autodesk Design Review.

georeferenced image

An image that references real-world coordinates in its correlation source. Example: Georeferenced images include GeoSPOT, GeoTIFF, and images that use world files as their correlation source.


A type of tagged image file format (TIFF) that supports georeferencing information.

GIS (Geographic Information System)

A computerized decision support system that integrates geographic data, attribute data, and other spatially referenced data. A GIS is used to capture, store, retrieve, analyze, and display spatial data.

global coordinate system

A method that converts the spherical coordinates of the Earth representing latitude and longitude into an AutoCAD Map 3D drawings Cartesian coordinate system, and accounts for the curvature of the surface of the Earth with a projection. A coordinate system is usually defined by a projection, an ellipsoid definition, a datum definition, one or more standard parallels, and a central meridian.

grid surface

See surface.


A regular pattern used to fill an area with a series of cross-angled lines.


The addition of shading to a surface to suggest three-dimensionality, shadow, or degrees of light and dark. Hillshading adds shading by casting the light of the sun across a surface from the direction and angle you specify.

implicit checkout

The action of checking out features by selecting them, without using the Check Out Features command. See also checkout, explicit checkout.

inner join

A type of join where records in the primary table are displayed only if there is a matching record in the joined secondary table. See also join, left outer join.

intersection (expression)

Two or more conditions joined with the logical operator And. An item is selected only if the item meets all specified conditions. Compare with union.

intersection (geometry)

The location where one line, surface, or solid crosses another so as to have one or more points in common.


A relationship that is established between attribute data and feature sources for the purposes of creating a new view of the data or for ad-hoc analysis.


An advanced raster image format from Joint Photographics Expert Group, featuring options for lossless compression, wavelet compression, incremental decompression, and support for up to 48-bit color.

key column

One or more columns in a table whose values are used to uniquely identify a record. To provide useful links, a key column should contain a unique value for each record. Also called a key field.

key value

A value stored on an object that specifies that value to match in the key field of a table.

key view

In a map book, an overview of the entire map with the current tile boundaries displayed.


Text placed on or near map feature to describe or identify them.


The first part of a spherical coordinate system used to record positions on the earths surface. Latitude indicates the angular distance north or south of the equator. See also longitude.


A resource that references a feature source or a drawing source. The layer contains styling and theming information, and optionally a collection of scale ranges. You add a layer to your map using Display Manager. Specific types of layers are drawing layer, feature layer, and surface layer.

layout template

In a map book, a named composition of viewports and annotation in paperspace. It includes the intended paper size and output scale for plotting and publishing. See also map book template.

left outer join

A type of join where all records in the primary table are displayed, whether they have a matching record in the joined secondary table or not.


Light Detection And Ranging. A remote-sensing method that can be used to generate an image of a surface.

link (external databases)

The connection between a drawing object and its related database data. The link data is stored on the linked drawing object and contains the name of the link template and the key value used to identify the associated record in the linked table. An object may have more than one link.

link (geometry)

An element of geometry that connects nodes. In a polygon topology, a link defines a polygon edge. Links can contain vertices and true arcs, and can be represented as a line, polyline, or arc. See also node.

link template

A data structure that contains the path information to a database table and specifies one or more key fields in that table.


To make all or part of a disk file read-only so that it cannot be modified by other users on a network. Object locking applies to objects that are being edited by another user. File locking applies to entire files, for example when an AutoCAD user wants to open a file while the file is being edited in AutoCAD Map 3D.

logical operator

A symbol such as And, Or, Not, =, >, >=, <, and <= used to define logical relationships.

long transaction

Transactions that extend over hours, days, or months, unlike the more typical database transactions that last for only seconds. Long transactions support atomicity, consistency, and durability, and can be committed or rolled back.


The second part of a spherical coordinate system used to record positions on the earths surface. Longitude measures angular distance east or west of the prime meridian, which runs through Greenwich, England. See also latitude.

main viewport

The viewport that represents a map tile in a sheet. See also viewport (paper space).


A collection of layers displayed within a consistent coordinate system and extents. See also layer.

Map Book

Manages your map book and contains commands for creating, editing, and publishing them. To view Map Book, click its tab in the Task Pane.

map book

A publishing option that divides a map into tiles and formats them into pages with a legend and an index/key. Create and edit map books from the Map Book tab in the Task Pane.

map book template

A special type of sheet set template used by a map book to generate sheets. The map tiles are generated based on the layout and viewport placeholder properties.

Map Explorer

Manages your mapping resources. To view Map Explorer, click its tab in the Task Pane.

map projection

A systematic representation of a spherical body, such as the earth, in a flat (planar) surface. Each map projection has specific properties that make it suitable for specific mapping needs.

map query

A set of conditions that specify the selection of drawing objects from source drawings. Conditions in a Map query can be based on the location or properties of an object or on data stored in the drawing or in a linked database table. See also topology query and database query.

map tile

A specific region of a map (model space view) for use on an individual sheet.

MapGuide Enterprise

A software platform for distributing spatial data over the Internet or on an intranet. MapGuide Enterprise is supported by Autodesk.

MapGuide Open Source

A software platform for distributing spatial data over the Internet or on an intranet. MapGuide Open Source is supported by the community (

MapGuide Server

The component of MapGuide Open Source or MapGuide Enterprise that hosts services and responds to requests from client applications through TCP/IP protocol.

MapGuide Viewer (AJAX viewer)

The version of the MapGuide Viewer component that does not need a download (also known as “zero-client viewer”). It works with Microsoft Internet Explorer, running on Windows, or with browsers such as Firefox on other operating systems, such as MacOS or Linux.

MapGuide Viewer (DWF Viewer)

The version of the MapGuide Viewer component that is based on a Microsoft ActiveX Control and has full support for the DWF format. It works with the Microsoft Internet Explorer browser only.

MapGuide Web Server Extensions

The MapGuide component that exposes the services offered by the MapGuide Server to client applications over the Internet or on an intranet using HTTP protocol.

Mercator projection

A map projection, designed by Gerhardus Mercator, in which the surface of the Earth is drawn as it would appear if projected on a cylinder wrapped around the earth. See also cylindrical projection.


A great circle passing through both poles, corresponding to a line of longitude.


Data about data. In the GIS context, metadata consists of information that describes the essential characteristics of geospatial data sets. See also FGDC CSDGM Standard.


Features with known coordinates, used to establish accurate and precise location on a map. See also control points.


A polygon object. A polygon differs from a closed polyline in that it stores information about its inner and outer boundaries.

naming scheme

The method of determining an individual map tile name. Examples include column/row, sequential, and data driven.

network analysis, network flood trace
network topology

A description of the spatial relationship between linear drawing objects (links and, sometimes, nodes). For example, a network topology can represent pipelines, streets, electrical transmission lines, and rivers.


A single point or a link end point or intersection in a topology. A node can be represented as a block or point object.

node topology

A description of the spatial relationship between geographic point objects in a drawing. Examples of node topologies include point sources of pollution and road signs.


In a theme, the scaling of data values relative to another data value. A common example is adjusting the thematic value based on the area, length, or perimeter of the entity.

object class

All the drawing objects that have been created using a specific object class definition. Use object classification to organize objects in your drawing based on the real-world features they represent, such as roads. Object classes allow you to create new objects that automatically have the appropriate properties and values for objects in your drawing. See also feature class.

object class definition

A definition of how to create a classified drawing object in a drawing. An object class definition can include information about the object type, default properties of the object, or default data that should be attached to the object.

object data

Attribute data attached to an object and stored in the drawing file. Compare with external data.


Open Geospatial Consortium. A non-profit, international, voluntary consensus standards organization that leads the development of standards for geospatial and location based services. (

one-to-many join

A join in which one record in the primary table corresponds to more than one record in the secondary table.

one-to-one join

A join in which one record in the primary table corresponds to one record in the secondary table.

OpenGIS Agent

The component of the MapGuide Server Web Extensions that implements several OpenGIS Web-mapping protocols to expose the services offered by the MapGuide Server to standards-based OpenGIS clients.

Oracle schema

See schema.

Oracle Spatial (OSE) feature

An earlier version of the Feature Data Objects (FDO) feature, used to store maps in Oracle Spatial.


Open Source Geospatial Foundation. A foundation created to support and build the highest-quality open source geospatial software. The goalof the foundation is to encourage the use and collaborative development of community-led projects. (


To create a new topology by combining elements of two distinct topologies. At least one of the original topologies must be a polygon topology.

overlay analysis

In AutoCAD Map 3D, a tool that provides spatial and data analysis capabilities for two sets of geospatial features.


In MapGuide, a compressed file that can speed up the process of loading data onto the server. Large source-data files can be zipped up in this file format and saved to a network location or copied to a CD.


A degree of latitude that circles the earth parallel to the Equator.

path trace

For a network topology, a trace begins at a specified point, finds the shortest distance to another point and is based on resistance (the length by default).

persistent locking

The ability to edit checked-out objects while you are offline, and then save your changes back to the data source when you return online.


Specifies location and size of elements (viewports, scale bar, north arrow, legend) in a map sheet.

plot template block

An AutoCAD block that contains plotting information such as title page text, plot layouts, legend, and other map annotation.


A polygon is a closed area that stores information about its inner and outer boundaries, and about other polygons nested within it or grouped with it. In a polygon topology, the polygon can be enclosed by any lines or arcs in the drawing. In addition, AutoCAD Map 3D supports a polygon object, sometimes called an Mpolygon or mapping polygon.

polygon topology

A description of the spatial relationship between geographic area features. Polygon topologies contain geometric links, nodes, and centroids. Examples of polygon topologies are land use and land cover maps, political boundaries, parcels, and soil types.

primary key

The property whose value uniquely identifies each feature within a feature class. Many feature classes use a single property for this purpose, for example, FeatureId. However, a feature class could have a list of properties such as street number, street name, and street type to uniquely identify a house address. You cannot edit primary key values for joined data.

prime meridian

The line of longitude drawn through Greenwich, England, used as the origin for longitude measurements.


User-defined settings specific to a given drawing.


For feature data, a single attribute of a class. A class is described by one or more property definitions. For example, a Road feature class may have properties called Name, NumberLanes, or Location. See also attributes or attribute data.

property alteration definition

The definition of properties you want to change during a query.

property data

Values associated with a geographic object, such as river depth, road width, or pipe diameter. In AutoCAD Map 3D, these items are represented as block attributes, values in object data tables, or values in a linked external database.

pseudo node

An unnecessary node in a geometric link. A pseudo node can be used to store information about geographic point location or to represent change from one link to another.


To generate output from a map book.


To remove all unused object definitions from an open drawing.


A set of executable statements that retrieve specific objects. For example, a layer-based query that displays only the objects on the layers that contain state and district boundaries. See map query, topology query, and database query.

Query Library

The set of queries saved in a drawing. You can add, delete, and modify queries in the Query Library.


A sequence of display properties used to render a theme; for example, a sequence of colors, line styles, or hatch patterns.

range of values

In a theme, a segment of data along a continuum, such as property value, temperature, or population.


Images containing individual dots (called pixels or cells) with color values, arranged in a rectangular, evenly spaced array. Aerial photographs and satellite images are examples of raster images used in mapping. Compare with vector.

raster-based surface layer
reference point

For a symbol, the point that controls the position of a symbol over a feature in a map. The default reference point is the center of the symbol.


The preparation of a map for digitizing by calibrating a digitizing table to convert an analog source to a digital file. See digitize.


Resistance is a measure of how hard it is to travel a link. The default measure of resistance is the length of the link. You can set the resistance to be related to what the link represents, such as pipe diameter or traffic speed.


In a raster image, the density of pixels-per-inch (PPI) or dots-per-inch.


In MapGuide, a feature source, drawing source, or application component that is stored in the resource repository and can be reused and shared.

resource (metadata)

In the Metadata feature, a resource is a generic term meaning any type of data set for which AutoCAD Map 3D can generate metadata. A resource could be a feature class, an object class, a schema, or a file.

resource repository

In MapGuide, an XML database that stores the resources created either by loading file-based data or by connecting to databases.

rubber sheeting

An editing method, used only when necessary, that attempts to correct errors by stretching a map to fit known control points or monuments.

rule (for feature themes)

A feature theme consists of a collection of rules. Each rule specifies a style and feature label for the features that meet the specified condition. You can add a legend label to provide a description of the condition of a rule. As a layer is drawn, each feature is compared to the rules in the order that they are listed. The first rule for which the feature meets the condition is used to specify the style and feature label for that feature.

save set

Objects that have been created or modified in the current drawing and are marked to be saved back to source drawings.


The ratio of the distance on a paper map to the distance on the ground. If a paper map has a scale of 1:100,000 (also represented as 1/100000), then a distance of 1 unit on the paper map corresponds to 100,000 units on the ground. On a digital map, scale represents the scale of the map from which the digital map was derived.

scale threshold

You can define different stylizations at different scale thresholds. For example, turn on the display of road names only when the drawing scale factor is below 1:5000.


The definition of multiple feature classes and the relationships between them. A schema is the logical description of the data types used to model real-world objects, and does not reference the actual data instances (a particular road or land parcel). Rather, it is metadata. See also feature class.


Spatial Data File. An open source file-based geodatabase that can contain multiple feature classes or types of data stored in tables with attributes and geometry. See SDF 2, SDF 3.


The previous version of the SDF file format. It was the native file format for Autodesk MapGuide (the last release was Autodesk MapGuide 6.5). Each SDF 2 file generally contained one feature class or type of data, for example points, lines, polygons, or text.


The current version of the SDF format. It is the native format for MapGuide Enterprise and MapGuide Open Source. Each SDF 3 file can contain multiple feature classes or types of data stored in tables with attributes and geometry. See feature class.


An Oracle database.


An individual named object in a sheet set that can be published. References a layout. In a DWF file, a plot layout containing a specific view of the original data.

sheet set

A named collection of sheets and subsets for publishing.

sheet subset

A named collection of sheets within a sheet set. An individual sheet can only be a member of a single subset.

sheet template

A drawing file that defines a title block and a layout for use in sheets. Can be specified for sheet sets and sheet subsets.

shortest path trace

See path trace.


The collection of servers that process MapGuide requests.

Site Administrator

A web-based application, installed with MapGuide Server, for managing a site and its servers.

Site Explorer

The tree view in MapGuide Studio that displays the resources stored in the resource repository.

site server

In a site, the server that contains the resource repository.


A method of reporting surface inclination as a ratio that expresses the horizontal distance in which the elevation changes by one linear unit. For example, if the ground rises 3 units over a horizontal distance of 15 linear units (meters or feet), the slope is 5:1 (5 to 1).

source drawing

A drawing file attached to another drawing. The set of all source drawings attached to a drawing is called the drawing set. Use a query to retrieve selected objects from multiple source drawings.


A generic term used to reference the mathematical concept of n-dimensional data.

spatial analysis

The process of understanding, extracting, or creating information about a set of objects. Spatial analysis includes techniques used to determine the distribution of objects over a network or area, and the relationships between those objects. The location of, proximity to, and orientation of objects can be analyzed with spatial analysis. It is useful for evaluating suitability and capability, for estimating and predicting, and for interpreting.

spatial context

The general metadata or parameters within which the geometry for a collection of features resides. In particular, the spatial context includes the definition of the coordinate system, spheroid parameters, units, spatial extents, and so on, for a collection of geometries owned by features.

spatial data

Information about the location and shape of geographic features, and the relationships between those features. See also feature.

Spatial Data File

See SDF.

spatial database

A database containing information indexed by location.

spatial filter

A selection of objects that specify which records to display in the active table or query. When a spatial filter is active, the Data View displays only those records linked to selected objects. Compare with SQL filter.

spatial index

An index created in an Oracle Spatial database by dividing the extents of the drawings in the database into rectangular tiles. AutoCAD Map 3D uses the index to locate the geometry to be imported.

spherical coordinate system

A coordinate system measured on the surface of a sphere and expressed as angular distances. Compare with Cartesian coordinate system.


See ellipsoid.

SQL filter

A series of SQL expressions that specify which records to select in the active table or query. When an SQL filter is active, the Data View displays only those records that match the filter criteria. Compare with spatial filter.


Settings that specify how to display the feature or drawing objects in a Display Manager layer. For example, a polygon style that makes parcel polygons 50% transparent and which appears at a scale of 1:50000. One or more styles can be applied to a single element.

style library

Use the style library to store the styles you use frequently. You can drag and drop these styles onto any element in any other display map.


The process of assigning display characteristics (such as line color, line pattern, fill color, fill pattern, and so on) to feature (points, polylines, polygons). See also theming.


Visually or textually changing the display of drawing objects according to the assigned styles, rather than displaying them with their native object properties. See also style.


A user who controls user IDs, passwords, and access to sensitive procedures.

supplementing distance

The maximum distance between 3D polyline vertices. If the distance between vertices is greater than specified, then points are added along the 3D polyline in equal increments that are less than or equal to the supplementing distance.

supplementing factors

Add vertices along 3D polylines that are long and contain few vertices. The supplementing distance is the maximum distance between vertices. If the distance between vertices is greater than specified, then points are added along the 3D polyline in equal increments that are less than or equal to the supplementing distance. The smaller the distance, the greater the number of supplemented points.


A network of elevation data. AutoCAD Map 3D supports raster-based grid surfaces, such as DEM, DTED, and ESRI Grid. In these types of surfaces, the points of a surface are connected into a grid, which are then used to interpolate contours, and to generate profiles and cross-sections. A surface represents the ground condition at a particular time or event.

surface layer

A layer in Display Manager containing a raster-based surface such as a Digital Elevation Model (DEM), an ESRI Grid file, or Digital Terrain Elevation Data (DTED). A surface layer is brought in using Data Connect. See also feature layer, drawing layer, AutoCAD layer.


A bitmap or vector image that is used to represent a point.

symbol library

In MapGuide Studio, a collection of related symbols. Image files are converted into symbols when they are brought into the symbol library. The symbol library is stored in the resource repository.

symbol table

A term referring to the storage of named objects, including linetypes, layers, text styles, and blocks.


A set of data arranged in records (rows) and fields (columns). When a table is displayed in a grid, records display in horizontal rows and fields display in vertical columns. Each field value in the table displays in a cell.

Task Pane

A AutoCAD Map 3D window that provides the tools you require to accomplish your main mapping tasks: creating, displaying, styling, analyzing, and publishing maps. The Task Pane contains tabbed views: Map Explorer, Display Manager, Survey, and Map Book. Map Explorer enables you to manage the resources you use to create your maps. Display Manager provides tools to create maps, and create styles and themes. With Map Book, you can print, publish and share maps. You can resize and move the Task Pane palette.

task workflow

An overview of the steps to perform common GIS tasks.

template file

A file that formats another file, such as a text file for saving information from queried objects. See also dot variable, query, and link template.

thematic map

See theme.


A theme is a special style used to vary the stylization based on some property of the objects. For example, instead of just coloring the lakes blue, you could vary the shade of blue based on the depth of the lake. Instead of just altering the line width of the roads, you could vary the line width based on traffic flow.


The process of styling feature according to an attribute value. See also styling.

tiling scheme

The method of breaking a large map into multiple smaller tiles. Options include by area, by number, and custom.


A radius around a node or linear object used to search for drawing errors.

tolerance (drawing cleanup)

The minimum distance allowed between linear objects or nodes during drawing cleanup. If two linear objects or nodes are separated by a distance less than the tolerance, AutoCAD Map 3D corrects the error.


An Autodesk data management solution for utility companies, municipalities, and engineering firms. Autodesk Topobase consists of a set of industry-specific modules built on AutoCAD Map 3D and MapGuide, all of which use Oracle as the central data store.


A set of geometric relationships between drawing objects, including links, nodes, and centroids. Topology describes how lines, nodes, and polygons connect and relate to each other, and forms the basis for advanced GIS functions such as network tracing, spatial analysis, buffer analysis, overlay analysis, and dissolving a polygon topology.

topology query

An extension to a Map query that applies to a loaded topology. See also map query.

transparent command

A command started while another is in progress. Precede transparent commands with an apostrophe.

transverse cylindrical projection

A map projection, in which the surface of the Earth is drawn as it would appear if projected on a cylinder wrapped around the earth in an east-west direction. Compare with cylindrical projection.

UDL (Universal Data Link)

File with.udl extension that includes the name and location of the database table and the software used to create the file. Windows uses a UDL file to identify a data source. Using the information in this file, programs such as AutoCAD Map 3D can view and update data from external databases.


Two or more lines within a specified tolerance of each other that do not meet.


Two or more conditions joined with the logical operator Or. An item is selected only if the item meets at least one of the specified criteria. Compare with intersection (expression).

Universal Transverse Mercator (UTM) projection

A specific implementation of the Mercator projection, designed for use around the world. See also Mercator projection.


A mathematical calculation of an object with precise direction and length. Vector data is stored as X,Y coordinates that form points, lines, and areas. Compare with raster.


A database function that allows multiple copies of a spatial dataset to be stored and tracked by date of creation, data of change, and so on.

vertical exaggeration

An increase of vertical scale relative to horizontal scale, used to make elevation changes easier to differentiate.

viewport (paper space)

A view of modelspace from a layout.


A multiple resolution image file compressed using a lossy compression that enables large graphics to load much faster due to the reduction in file size. Wavelet compression is based on a mathematical algorithm in which graphic images can be reduced to a small fraction of their original size.


The removal of points along a selected 3D polyline, which may represent a contour. The weeding factors determine the number of points removed. You can use weeding to reduce the amount of point information taken from the contours that may not be necessary to generate an accurate surface.

weeding factors

You can use the weeding factor settings to reduce redundant points along 3D polylines by ignoring vertices that are close together or along a straight line. A larger distance and deflection angle will weed a greater number of points. Distance is an absolute measure and the angle is measured in degrees. The larger the distance value, the greater the number of weeded points. The weeding factors must be less than the supplementing factors.

A point is weeded by calculating its location in relation to the vertices before and after it. If the length between these three points is less than the weeding length value, and the deflection angle is less than the weeding angle value, then the middle point is not added to the contour data file.


Web Feature Service. A web service based on the specification defined by the OGC. Acts as a source of feature data.


Web Map Service. A web service based on the specification defined by the OGC. Produces an image (for example, a PNG or JPG image) of geospatial data.


An automated set of tasks that can be arranged to run in series or parallel. The output of one task can be used as the input of another task. The user can configure the sequence and parameters for execution graphically.

workflow activity

A single step in a workflow that executes a command or set of commands.

workflow binding

A relationship between activities such that the output of one activity is used as the input of another.


Contains the commands and tools for specific tasks. The Tool-based Ribbon workspace is tailored to those familiar with the AutoCAD ribbon, while the Task-based Ribbon workspace is optimized for working with AutoCAD Map 3D.

To change your workspace, click the name of the current workspace in the status bar and select a different workspace from the list.

zero-client viewer

To change the display magnification so that it focuses on progressively smaller areas (when you zoom in) or larger areas (when you zoom out) of an image.

zoom extents

To magnify a drawing based on its extents so that the view shows the largest possible view of all spatial objects.