 Antialiasing

antialiasing is a software technique for diminishing jaggies  stairsteplike lines that should be smooth. Jaggies occur because the output device, the monitor or printer, does not have a high enough resolution to represent a smooth line. Antialiasing reduces the prominence of jaggies by surrounding the stairsteps with intermediate shades of gray (for grayscaling devices) or color (for color devices). Although this reduces the jagged appearance of the lines, it also makes them fuzzier
 APP6

Allied Procedural Publication 6 is a NATO standard for military map marking symbols. It provides common operational symbology along with details on their display and plotting to ensure the compatibility, and to the greatest extent possible, the interoperability of NATO Land Component Command, Control, Communications, Computer, and Intelligence (C4I) systems, development, operations, and training
 azimuth

An azimuth is defined as a horizontal angle measured clockwise from a north base line. This north base line could be true north, magnetic north, or grid north. The azimuth is the most common military method to express direction. When using an azimuth, the point from which the azimuth originates is the center of an imaginary circle . This circle is divided into 360 degrees or 6400 mils. NORTH IS 0/360 AZIMUTH
 background data

Reference data for the data that users want to interact with (business data)
 Bezier curves

Curved lines (splines) defined by mathematical formulas. Bezier curves employ at least three points to define a curve. The two endpoints of the curve are called anchor points. The other points, which define the shape of the curve, are called handles, tangent points, or nodes. Attached to each handle are two control points. By moving the handles themselves, or the control points, you can modify the shape of the curve. In vector graphics, Bezier curves are used to model smooth curves that can be scaled indefinitely
 bitmap

A representation, consisting of rows and columns of dots, of a graphics image in computer memory. Bitmapped graphics are often referred to as raster graphics. The other method for representing images is known as vector graphics or objectoriented graphics. With vector graphics, images are represented as mathematical formulas that define all the shapes in the image
 bounds

Represents an axisaligned bounding box
 bounding box

An invisible box surrounding a graphical object and determining its size. The minimum bounding box for a point set in N dimensions is the box with the smallest measure (area, volume, or hypervolume in higher dimensions) within which all the points lie
 business data

The data that users want to interact with
 Cartesian

Cartesian coordinates provide a method of indicating the positions of points on a twodimensional (2D) surface or in threedimensional (3D) space. The Cartesian plane consists of two perpendicular axes that cross at a central point called the origin. Positions or coordinates are determined according to the east/west and north/south displacements from the origin. The east/west axis is often called the x axis, and the north/south axis is called the y axis. For this reason, the Cartesian plane is also known as the xy plane. Cartesian threespace, also called xyz space, has a third axis, oriented at right angles to the xy plane. This axis, usually called the z axis, passes through the origin of the xy plane
 controller

application component that handles user interaction
 culling

In rendering, zculling is early pixel elimination based on depth, a method that provides an increase in performance when rendering of hidden surfaces is costly. It is a direct consequence of zbuffering, where the depth of each pixel candidate is compared to the depth of existing geometry behind which it might be hidden
 Discretize

Discretization concerns the process of transferring continuous models and equations into discrete counterparts. It can be used for vector shapes, for example
 draping

The process of projecting a 2D feature on a 3D surface
 ellipsoid

In geodesy, a reference ellipsoid is a mathematicallydefined surface that approximates the geoid, the truer figure of the earth, or other planetary body. Because of their relative simplicity, reference ellipsoids are used as a preferred surface on which geodetic network computations are performed and point coordinates such as latitude, longitude, and elevation are defined
 EPSG

The EPSG geodetic parameter dataset is a structured repository of data required to identify coordinates through a coordinate reference system (CRS) definition, and to define transformations and conversions that allow coordinates to be changed from one CRS to another CRS. The EPSG Geodetic Parameter Dataset is maintained by the Geodesy Subcommittee of OGP
 features

A representation of a geometrical shape and its attributes
 geodesy

also named geodetics, a branch of earth sciences, is the scientific discipline that deals with the measurement and representation of the earth, including its gravitational field, in a threedimensional timevarying space. Geodesists also study geodynamical phenomena such as crustal motion, tides, and polar motion. For this they design global and national control networks, using space and terrestrial techniques while relying on datums and coordinate systems
 geodetic datum

A geodetic datum is a reference from which measurements are made. In surveying and geodesy, a datum is a set of reference points on the earth’s surface against which position measurements are made, and (often) an associated model of the shape of the earth (reference ellipsoid) to define a geographic coordinate system. Horizontal datums are used for describing a point on the earth’s surface, in latitude and longitude or another coordinate system. Vertical datums measure elevations or depths
 geoid

Essentially the figure of the earth abstracted from its topographical features. It is an idealized equilibrium surface of sea water, the mean sea level surface in the absence of currents, air pressure variations and so forth, and continued under the continental masses
 geometry

A geometrical object with a bounding box and a focus (or center) point
 GLSL

OpenGL Shading Language is a highlevel shading language based on the syntax of the C programming language. It was created by the OpenGL ARB to give developers more direct control of the graphics pipeline without having to use assembly language or hardwarespecific languages
 GPS

Global Positioning System
 GPU

Graphics Processing Unit. Common term for the chip responsible for graphics hardware acceleration
 Hypsometry

terrain analysis functionality that uses elevation data to compute terrain properties such as slope and shading
 IDE

Integrated Development Environment
 interpolate

Insert an intermediate item into a series of items by estimating or calculating it from surrounding known values
 JSON

JavaScript Object Notation is a lightweight datainterchange format. It is easy for humans to read and write. It is easy for machines to parse and generate. It is based on a subset of the JavaScript Programming Language. JSON is a text format that is completely language independent but uses conventions that are familiar to programmers of the Cfamily of languages. These properties make JSON a good data interchange language
 layer

Container used to visually represent model data in a view
 lazy loading

A design pattern commonly used in computer programming to defer initialization of an object until the point at which it is needed. It can contribute to efficiency in the program’s operation if properly and appropriately used
 mesh

A polygon mesh or unstructured grid is a collection of vertices, edges and faces that defines the shape of a polyhedral object in 3D computer graphics and solid modeling. The faces usually consist of triangles, quadrilaterals or other simple convex polygons, since this simplifies rendering, but may also be composed of more general concave polygons, or polygons with holes.
 model

A container for domain objects
 model reference

The coordinate reference system that is used to locate model data on earth
 MS2525

MILSTD2525 is a common warfighting symbology, and an American standard equivalent to APP6
 multiresolution

a multiresolution object can be described at different levels of resolution
 oblate spheroid

An oblate spheroid is a rotationally symmetric ellipsoid having a polar axis shorter than the diameter of the equatorial circle whose plane bisects it. The shape of the Earth is very close to that of an oblate spheroid
 OpenCL

Open Computing Language, the crossplatform standard interface for general parallel computation on GPUs
 OpenGL

Open Graphics Language, the standard interface for visualization using the GPU. This standard is available on many platforms and drivers are available from all major graphics card vendors
 orthographic

as in orthographic projection. When the human eye looks at a scene, objects in the distance appear smaller than objects close by. Orthographic projection ignores this effect to allow the creation of toscale drawings. Orthographic projections are a small set of transforms often used to show profile, detail or precise measurements of a three dimensional object. Common names for orthographic projections include plane, crosssection, bird’seye, and elevation. While orthographically projected images represent the three dimensional nature of the object projected, they do not represent the object as it would be recorded photographically or perceived by a viewer observing it directly
 orthorectification

Processing an image to geometrically correct it so that the scale of the photograph is uniform and it can be measured as a map
 pan

Move the map by clicking or touching it and dragging it
 perspective

as in perspective projection. When the human eye looks at a scene, objects in the distance appear smaller than objects close by  this is known as perspective. While orthographic projection ignores this effect to allow accurate measurements, perspective definition shows distant objects as smaller to provide additional realism
 polyline

Continuous line composed of one or more line segments
 primitive

A geometric primitive is of the simplest (meaning 'atomic' or irreducible) geometric objects that the system can handle. The most primitive primitives are point and straight line segments
 Qt

Qt is an opensource widget toolkit for for developing graphical user interfaces (GUIs) and multiplatform applications that run on all major desktop platforms and most mobile or embedded platforms.
 Raster data

Data that consists of a grid of evenly sized cells
 raster warping

Visualization of imagery or elevation data in a geographical projection that is different from that of the source data. The raster data needs to be warped into the target earth projection for accurate visualization.
 raw

Unprocessed. The term refers to data that is passed along to an I/O device without being interpreted
 RGBA

Red Green Blue Alpha. RGBA is a use of the RGB color model, with extra information. The color is RGB, and may belong to any RGB color space, but an integral alpha value enables alpha blending and alpha compositing. The alpha channel is normally used as an opacity channel
 snapping

Snapping layer objects into position pulls the objects to one another or to ruler subdivisions, grid lines, guides, or guide points so that you can control the placement and alignment of the objects
 SQLite

SQLite is an inprocess library that implements a selfcontained, serverless, zeroconfiguration, transactional SQL database engine. The code for SQLite is in the public domain and is thus free for use for any purpose, commercial or private. SQLite is an embedded SQL database engine. Unlike most other SQL databases, it does not have a separate server process. SQLite reads and writes directly to ordinary disk files. A complete SQL database with multiple tables, indices, triggers, and views, is contained in a single disk file. The database file format is crossplatform. SQLite is a compact library. With all features enabled, the library size can be less than 300KiB, depending on compiler optimization settings. If optional features are omitted, the size of the SQLite library can be reduced below 180KiB
 Vector data

Data that consists of geometries
 vertex

a vertex (plural vertices) is a special kind of point that describes the corners or intersections of geometric shapes. Vertices are commonly used in computer graphics to define the corners of surfaces (typically triangles) in 3D models, where each such point is given as a vector
 vertex array

Instead of specifying individual vertex data in immediate mode (between glBegin() and glEnd() pairs), you can store vertex data in a set of arrays including vertex coordinates, normals, texture coordinates and color information. You can draw geometric primitives by dereferencing the array elements with array indices
 view

Visual representation of model data
 viewing frustum

The region of space in the modeled world that may appear on the screen. it is the field of view of the notional camera
 WGS

The World Geodetic System is a standard for use in cartography, geodesy, and navigation. It comprises a standard coordinate frame for the earth, a standard spheroidal reference surface (the datum or reference ellipsoid) for raw altitude data, and a gravitational equipotential surface (the geoid) that defines the nominal sea level.The latest revision is WGS 84 (dating from 1984 and last revised in 2004), which will be valid up to about 2010. WGS 84 is the reference coordinate system used by the Global Positioning System
 WPF

Windows Presentation Foundation (WPF) is a graphical subsystem originally developed by Microsoft for rendering user interfaces in Windowsbased applications
 world reference

A coordinate reference system and a map projection used to represent earth data in a 2D view
 shader

A set of software instructions that is used primarily to calculate rendering effects on graphics hardware with a high degree of flexibility. Shaders are used to program the graphics processing unit (GPU) programmable rendering pipeline. They are simple programs that describe the traits of either a vertex or a pixel. Vertex shaders describe the traits (position, texture coordinates, colors, and so on) of a vertex, while pixel shaders describe the traits (color, zdepth and alpha value) of a pixel