Chapter 8

GIS software

Introduction

• Chapter 1 : four technical parts of GIS(network , hardware , software , database ) .

• This chapter 8 : concerned with GIS software , the geoprocessing engine of a complete , working GIS .

( GIS software packages aim to provide a unified approach to working with geographic information )

GIS software builds : 1- foundation of a computer operating system –

the instruction set that controls all the activities of a computer .

2- capabilities to provide a controlled environment for geographic information management , analysis and interpretation .

3- support for geographic data types and processing capabilities to facilitate geographic information science .

Evolution of GIS software • GIS market grew in the 1970s and 1980s . • In the late 1970s and early 1980s , the

standard means of communicating with a GIS was to type in command lines .

• Two key developments in the late 1980s : 1- command line interfaces were supplemented

and eventually replaced by ( GUIs ) . 2- a customization capability was added to allow

specific-purpose applications to be created from the generic toolboxes .

Evolution of GIS software

• new terms were developed to distinguish these sub-types of GIS software:

1- planning information systems . 2- AM / FM . 3- land information system .

Architecture of GIS software • GIS is usually first introduced into organizations in

the context of a single , fixed-term project . • The technical components of an operational GIS

are assembled for the duration of the project , which maybe from several months to a few years

• As GIS becomes more pervasive , organizations learn more about it and begin to become GIS is a useful way to structure many of the organization’s assets , processes and workflows .

Three-tier architecture of GIS software system :

Presentation

Business logic

Data server

User interface

tools

Data management

Data

Three types of GIS implementation configuration

• Project . • Department . • Enterprise .This type of computing architecture is usually

referred to as client-server because clients request data or processing services from servers that perform work to satisfy client requests.

Software data models and customization

• Customization is the process of modifying GIS software to create a specific-purpose application .

• It can be as simple as deleting unwanted controls from a GUI .

• Late 1980s , when customization capabilities were first added to GIS software , each vendor had to provide a proprietary customization system simply because no standard customization systems existed .

GIS on the desktop and on the internet Feature Desktop Network

Client size Thick Thin

Client platform Windows Browser

Server size Thin / thick Thick

Server platform Windows / Unix Windows / Unix

Component standard Com Java

network LAN / WAN Internet

Building GIS software system:

GIS software system: are built released as GIS S.W products by GIS- vendor soft development and product teams:

Key of GIS Software system: *Architecture *User interface*Tools, data manager*Data model*Customization environment

The key GIS software components deal with user application, tools and data access.

Key of GIS software system “advantages”

• Building components gives greater control over system capabilities.

• Enable specific-purpose optimization.• Buying components can save valuable time and

many. Example of components:It have been purchased and licensed for use in GIS

software system (Arc view GIS, Microsoft visual Basic)

*The key GIS software component deals with user applications, tools, and data access.

*A key GIS implementation issue is whether to buy a system or to build one, increasingly users prefer to buy complete system.

Modern GIS software system has three types of components:*User applications ( locate data, make, maps, geocode) *Geographic tools *Data access

The main data access:*Vector *Raster*Spatial reference *Data manager

• Vector and Raster:1 Sub system are responsible 2 Low level manipulation • Spatial reference:1 Coordinate transformation 2 Map projection • Data manager:1 Responsible for storing geographic objects2 Provide sophisticated service

Types of GIS software system:

• The distinctive feature of professional GIS include data collection and editing, database administration advanced geoprocessing and analysis and other specials tools.

Example of professional GIS software:• ESRI ArcInfo • Smallworld

Component GIS are used by developers to create focused application

For examples: *blue marble *geographic geobject*esriobjects*Maplinfo Mapx*Cost is 1000-2000 for the developer kit and 100 per

GIS viewer

• These include• *ESRI’s ,ArcExplorer, Intergraph’s GeoMedia

viewer , MapInfo’s ProViewer• **They help to establish market share

Internet GIS• Internet GIS have the highest number of users

although internet users typically focus on simple display and query tasks

Others types of GIS software For example: *ESRI ArcInfo *ArcView*Raster based CAD based and GIS application servers are also important types of GIS software