ArcIMS

Advanced GIS

Fall 2003

GEOG 4850/5850

Map Service/AXL• Fundamental component of ArcIMS• To create a MapService, you first need to make a map

using the ArcIMS Author application. There, you add data layers to a map and specify how those layers will be organized and symbolized.

• After you have the map looking the way you want, you create a map configuration file (AXL extension). The map configuration file is a text file that stores information about your map design. (Map configuration files will be referred to as AXL files throughout this course.) Together, the AXL file and a MapService are what you need to publish maps on the Web.

Two types of MapServices: Image and Feature

• A Feature MapService streams data as vectors. An Image MapService sends a map image in JPEG, PNG, or GIF format.

Image MapService

• When you use an Image MapService, a map image is generated by the map server in JPEG, GIF, or PNG format and sent to the client computer that requested it. No special processing is required by the client computer. All the processing takes place on the map server, which generates a new map image each time it receives a request

Feature MapService• With a Feature MapService, the map server bundles

the data as vectors and attributes and sends it to the client through a process called streaming. Unlike Image MapServices, Feature MapServices are locally cached and the client computer can perform further geoprocessing on the data

streaming• A type of data transmittal in which data is not

downloaded from a server, but rather temporarily cached in a local computer's memory. Users interact with the data held in their computer's local cache. Streamed data is usually sent from the server in a compressed format. When received by the client (local computer) the data is uncompressed and displayed using software designed to interpret and display the data rapidly.

http://maps.esri.com

• Logon to maps.esri.com.

• Many applications of ArcIMS are shown here.

• Projection-on-the-fly

• Geo-Game

• California Climagraph

ArcIMS Applications• ArcIMS consists of four applications: Author, Administrator, Designer,

and Manager. In this topic, you'll learn how these applications work together to allow you to create and manage an ArcIMS Web site.

• Designing a Web site that provides geographic content requires careful planning. The first step to understanding how ArcIMS works is to create geographic content, then publish it as a MapService.

• To create a MapService, you add data to a map and decide how you want it to be presented on the Internet. This information is stored in the AXL (map configuration) file. As you will see, you use the AXL file to start a MapService.

• After creating a MapService, you use ArcIMS to create a Web page that can handle the MapService. That involves designing the Web page and determining how the MapService will be presented. The MapService allows the map content (defined in the AXL file) to be published on the Internet and provides the framework for your Web site's functionality.

Author• ArcIMS Author is the application you use to define the content for a

map that you want to publish on the Internet. You decide what data will be shown and how it will appear on your map. First, you need to find the appropriate data sources for your Web site. You can use shapefiles, a variety of different image types, ArcSDE™ layers, and coverages stored in ArcSDE for Coverages. Through a Catalog window, you add this data to your map as layers. Layers reference the data source. In other words, a pathname is stored for the location of the actual file or files that comprise the data.

• Once you have added data layers, ArcIMS Author allows you to add tools to help users navigate your map, like pan and zoom, and to investigate your map, like Map Tips and Identify. The final output from Author is a map configuration file, or AXL file. AXL files are text files that define all the map properties, including layer symbology. Author writes your choices and definitions in ArcXML, an Extensible Markup Language (XML) used specifically for creating Web-based products.

extensible markup language (XML)

XML is a markup language derived from SGML (Standard Generalized Markup Language) that defines the various components of a document by identifying and separating content, structure, and style. It was created and is maintained by the World Wide Web Consortium (W3C) to facilitate more standardized and structured user documents for the World Wide Web. It has now moved beyond the World Wide Web and is adopted by organizations around the world as the standard for producing both digital and analog mediums.

Administrator• At any given moment, a GIS-enabled Web site will be receiving and

providing numerous requests and responses for MapServices. To maintain an effective and efficient Web site, you will need to monitor its activity and fine-tune its operation. ArcIMS Administrator is the ArcIMS application you use to control how your Web site operates.

• One of the essential tasks that you perform with Administrator is creating and starting MapServices. Once you have created a map in Author, you convert the resulting map configuration file (AXL file) to a MapService in Administrator. Basically, in Administrator you are publishing the content of an AXL file onto the Internet

• Besides site administration, ArcIMS Administrator allows you to manage other components of your Web site, including spatial servers, virtual servers, and special folders for storing information gathered from users. Data administrators can also check statistical information about the site's performance and manage collaborative tools such as EditNotes and MapNotes. You'll learn more about the features available in ArcIMS Administrator in Module 4, Working with ArcIMS Administrator.

Designer• To publish MapServices, you need a Web site

that has been designed to handle them. ArcIMS Designer is the application you use to construct a Web site tailored to the individual MapServices that you created. With Designer, you create the look and feel of the site as well as determine functionality by adding tools for zooming, panning, querying, and map layer treatment

• An important decision you will need to make is what type of client viewer your Web site will use. There are two basic client viewer templates accessible through ArcIMS, each offering a range of capabilities. The HTML client viewer permits only image files to be downloaded, while the Java-based client viewer allows both image and feature data transfer

Example – Creating an ArcIMS website - 1st step

• Author – The first step is to use ArcIMS Author to create a map that you want to display on a Web site. In Author, you add the different geographic layers, organize them how you want, and choose their symbology. When your map is complete, you output it as a text file with an AXL extension. In the ArcIMS documentation, this file is referred to as the map configuration file.

Example – Creating an ArcIMS website - 2nd

step

1. Once the map configuration file is created, you need to register it before it can be published on the Internet. This step is called starting a MapService, and you use ArcIMS Administrator for this task. The map configuration file you generated using Author is the input to a MapService. When a map server receives a request for a MapService, the MapService follows the instructions in the map configuration file and sends data to the client. Administrator is the application that allows this communication to occur.

2. Second, use the map configuration file to create and start a MapService in ArcIMS Administrator.

Example – Creating an ArcIMS website - 3rd step

1. Once the MapService has been created and started in Administrator, you are ready to design a site for public display. ArcIMS Designer has a wizard interface that guides you through the process of creating HTML pages and supporting files

Summary•

More and more, the Internet is becoming a common forum for analyzing and solving geographic problems. Developing an ArcIMS-powered Web site allows you to distribute your own geographic data and integrate it with data from other sites. The heart of an ArcIMS Web site is the MapService. A MapService defines how geographic data may be displayed on the Web. There are two types of MapServices: Image and Feature MapServices.

• ArcIMS consists of four applications: Author, Administrator, Designer, and Manager.

• ArcIMS Author is the application that allows you create a map and organize your data into an AXL file which you use to create a MapService.

• ArcIMS Administrator allows you to create and manage your MapServices.

Summary - 2

• ArcIMS Designer is the application you use to design and build ArcIMS viewers by combining MapServices with toolbar functions.

• ArcIMS Manager ties the other three applications together into a wizard-driven interface, and leads you through the process of authoring MapServices, designing Web pages, and administering sites.

• ArcIMS is the engine behind Geography Network, an Internet portal that facilitates finding geographic data and other content. Geography Network is the place to search for MapServices that others have created and where you can publish your own MapServices when you're ready.

ArcIMS Architecture and InstallationLesson Goal

• the multitier architecture of ArcIMS • how to use the ArcIMS help system • how to access ArcIMS Online • how to find technical documentation in the

ArcIMS Knowledge Base • the basic steps in the ArcIMS installation

process • how to test your configurations using the

ArcIMS Diagnostics Web page • how to quickly create a simple ArcIMS Web site

Server-Client Environment

• When a client makes a request for a MapService, the request is first handled by the Web server, then passed through to ArcIMS. A response is sent back through the Web server to the client.

• The server processes requests, creates and runs MapServices, and manages the Web site. Data sources managed by the server can include both database and file-based sources.

• The client is a user's Web browser or supported software program such as ArcGIS that accesses an ArcIMS viewer on the Web site. Through the viewer, a client sends requests and views or interacts with maps and data. The viewer provides the framework for the Web site; that is, it defines the site's appearance and functionality.

Webserver• ArcIMS needs a Web server that can be

extended to run Java code, either built-in or by using a servlet engine

• Servlet engines extend Web servers with a common applicaton programming interface (API) and allow them to process Java code. A servlet is a Java program that runs as part of a Web server and responds to requests made to a special URL. The most common use for a servlet is to extend a Web server by dynamically generating Web content. A servlet can be written so that it receives the request, acquires and processes the data as needed by the client, then returns the result to the client. Servlets are analogous to applets, except they work on the server side of the architecture.

Spatial Server

• ArcIMS spatial serverThe backbone of ArcIMS is the ArcIMS spatial server. The ArcIMS spatial server provides the functional capabilities for accessing and bundling maps and data into the appropriate format before sending them to a Web browser.

• When a request is received, the ArcIMS spatial server performs functions such as creating cartographic map image files, streaming map features, searching to query the database, geocoding for address matching operations, and extracting or "clipping" data to create a subset that can be sent back in shapefile format

Client side

• Client computers access an ArcIMS Web site using a Web browser or a supported software program, such as ArcExplorer 3 Java Edition or ArcGIS™. The client interacts with the Web site through the viewer created for the site. It is the viewer that controls the site's appearance and functionality.

• Standard ArcIMS includes HTML and Java viewers, and supports a full suite of other ESRI software clients such as ArcGIS, ArcExplorer, and ArcPad™, and other devices. If you want, you can choose from a variety of ready-to-use viewer templates or you can customize the standard ArcIMS viewer templates using VBScript or JavaScript.

Feature/HTML viewers

• Feature streaming (available with the Java viewer) serves information to a client browser in a specially optimized compressed format, resulting in true client/server processing capabilities. The new ArcIMS architecture allows more powerful clients to process "smart data" on the client computer to instantly perform many tasks without having to interact with the server.

• The HTML viewer performs less processing on the client computer than the Java viewer, making it a "lighter" client option. The HTML viewer may be the best solution for simple mapping applications that incorporate only Image MapServices.

ArcIMS Installation• Verify System Requirement: 256MB Ra, 226 MB space,

Win2000 or Solaris 7/8

• Typical/Customization

• You may be able to run ArcIMS spatial servers on several machines instead of one.

• Typical- Installing all components on one computer is suitable for sites with limited computing resources or those that expect a light volume of use.

Custom Installation

• A custom installation allows ArcIMS components to be distributed and increases the efficiency of high-volume Web sites.

• Adding more computers with ArcIMS spatial servers expands the processing capabilities of Web sites that get heavy traffic.

Testing the ArcIMS servlet connector

• it can be accessed through Start > Programs > ESRI > ArcIMS 3.1 > ArcIMS Diagnostics or type in http://kh309.easc.tntech.edu/servlet/com.esri.esrimap.Esrimap?cmd=ConnectorPing in browser’r URL space

Exercise – create a simple webmap using ArcIMS

• Load your county data (such as from neighboring counties, White, Cumberland, Fentress, etc..) to U:\Adv_GIS\YourName\Exercise

• Start ArcIMS

Authoring• the main features of the ArcIMS Author

interface • the types of data you can work with in

Author • how to add data using the Catalog • the different ways you can symbolize

feature layers in Author • how to save your map as a map

configuration file • the structure of ArcXML files

Authoring maps

• Create a axl file: map configuration file

• You will identify data layers for your map

• Symbolize layers and legend and scale setup

• Start ArcIMS Author application from program>Esri>ArcIMS 3.1> Author or access through Manager

Author toolbar

• Open: Select an existing map configuration file to edit (not available in Manager) Save Project: Save your work in a map configuration file Copy Map Image to File: Save a JPEG image of your current map display Close Project: Close the current project (not available in Manager) Add Layers: Opens the Catalog where you can browse for and add new data layers Print: Print the current map display to a default printer Scale Bar Properties: Set the map and scale bar units (available only in Manager)

File and Edit

Author – toolbar2

• Zoom to Previous: Zoom back to the previous extent Zoom to Next Extent: Zoom forward to the next extent (use after clicking Zoom to Previous) Zoom to Full Extent: Zoom to the full extent of all the layers in the map Zoom to Active Layer: Zoom to the extent of the active layer Zoom In: Zooms in when you click or draw a box on the map Zoom Out: Zooms out when you click or draw a box on the map Pan/Pan One Direction: Move the map display without changing the map scale

Author toolbor 3

• Identify: Shows feature attributes when you click on the features on the map Find: Allows you to type in a word to find features in one or more layers Stored Query: Creates a predefined query on a feature attribute table Geocoding Properties: Defines the properties for the street file you want to use for address matching and builds a geocoding index MapTips: Enables MapTips using an attribute of a layer Layer Properties: Defines the layer symbology Clear All Selection: Clears the selected features in all layers

Add Data - ArcCatalog

• Navigate to folder where you have data stored, and click on Add Layer

• ArcIMS supports the following data types: shapefiles, ArcSDE layers, many image formats, and ArcInfo™ coverages accessed through ArcSDE for Coverages.

shapefile

• A shapefile is a standard format for storing geometry and attribute information for a set of geographic features. The geometry for a feature is stored as a shape comprised of a set of vector (point, line, or polygon) coordinates. Every feature in a shapefile must have the same shape. Shapefiles are a vector file format for storing the location and attribute information of point, line, and polygon features. The name "shapefile" is somewhat misleading because each shapefile is comprised of at least three files: shapefile_name.shp, shapefile_name.shx, and shapefile_name.dbf.

• A shapefile has three core files with different extensions that indicate their contents:

• SHP: Stores feature geometry (shape and location information) • SHX: Stores the index of the feature geometry • DBF: A dBASE file that stores the attribute information for the features

ArcIMS and shapefiles

• These three files must be stored in the same folder. Shapefiles may also have other associated index files that speed analysis and querying. These files are not required.

• ArcIMS does not allow a shapefile to have field names longer than 10 characters. Also, shapefiles that contain duplicate field names cannot be drawn in ArcIMS.

Image File in ArcIMS• Image data is raster-based data in which each cell, or pixel, has a

certain value. Common examples of images are satellite images, aerial photographs, and scanned documents. On maps, an image is often used as a background layer.

• You've learned that ArcIMS supports three types of output image formats (GIF, JPEG, and PNG), but the ArcIMS spatial server is able to read many types of image formats. This means that when you use imagery in your map, the source image file can be stored in a variety of formats. These images can be added as references to the map configuration file (AXL file) to be registered by a MapService.

• In ArcIMS Author, you can add and view images in some source formats, including BMP, JPEG, GIF, and TIF. Images in other formats such as MrSID, ERDAS IMAGINE, and image directories can be added to Author, but they cannot be viewed. The image reference is saved in the map configuration file.

Image file format for ArcIMS• Arc Digitized Raster Graphics (ADRG), ASRP, Bitmap (BMP),• Band Interleaved by Line (BIL), Band Interleaved by Pixel (BIP) • Band Sequential (BSQ), Controlled Image Base (CIB) • Compressed Arc Digitized Raster Graphics (CADRG) • ERDAS GIS, ERDAS IMAGINE • GeoTIFF, IMPELL,JPEG File Interchange Format (JFIF) • Joint Photographic Experts Group (JPEG) • Multiresolution Seamless Image Database (MrSID) • National Imagery Transmission Format (NITF) • Portable Network Graphics (PNG), SUN Microsystems Computer (SUN) • Tagged Image File format (TIF), USRP • ESRI ArcInfo GRID, ESRI ArcView Image Catalog • ESRI Spatial Database Engine Raster (ArcSDE Raster) • Some image formats store georeferencing information in the header of the

image file. Other image formats store this information in a separate ASCII file. This file is generally referred to as the world file, because it contains the real-world transformation information used by the image. ArcIMS requires that world files be included with image layers that use them.

Creating a map

• In ArcIMS Author, there are many ways to customize the appearance of your maps. You can control how the source data is displayed and how users interact with the layers. You can set scale bar properties and add, reorder, and remove layers.

• You use the Layer Properties dialog to access most layer-specific properties. In this dialog, you can do things such as change the name of a layer, customize its symbology, and add text labels for features.

• The symbology you choose for displaying layers greatly affects how readers interpret the map. Learning how to display your layers clearly and efficiently will help your audience understand your data and may also reveal patterns not otherwise apparent. ArcIMS provides a wide variety of symbol styles and colors you can use to represent layer

Scale bar properties• A scale bar helps users interpret the data shown on your map.

ArcIMS Author adds a scale bar automatically at the bottom of the map display. To ensure the accuracy of the scale bar, you need to specify the map units of your data, the scale units, and the screen units you want to use for measurement.

• Map unitsMap units are the units in which your data sources are stored. You can work with spatial data that stores feature locations as unprojected geographic coordinates (latitude and longitude coordinates stored in decimal degrees) or projected x,y coordinates. Projected data is data stored in real-world units such as meters or feet.

• Setting the map units is crucial if you want to enable accurate measuring and buffering on your Web site. The map units will be written to the map configuration file (as the MAPUNITS element).

• Scale unitsScale units are the units ArcIMS uses for reporting measurements and dimensions in the scale bar. You can choose any units (e.g., miles, feet, meters, or kilometers) appropriate for the map display you are working with.

Scale bar

• Screen unitsScreen units are used to physically measure a distance using a ruler displayed on your monitor to estimate true distance (e.g., 1 inch on the monitor equals 50 feet in the real world). You can set screen units as inches or centimeters. In Author, you set the map units, scale bar units, and screen units using the Scale Bar Properties command on the View menu. When you're creating a map using ArcIMS Manager, you access the Scale Bar Properties either by right-clicking the scale bar or clicking the Scale Bar Properties button. In Author, you can choose to not display the scale bar by unchecking the Scale Bar command on the View menu. You cannot remove the scale bar in Manager.

Legend - layer

• After you add data using the Catalog, each source dataset appears as a layer in the legend.

• Many operations in ArcIMS work only on the active layer. For example, you can identify only features of the active layer. To make a layer active, click the layer name in the legend. When a layer is active, it is enclosed by a rectangular box.

Order of layers

• For best display, point and line feature layers should be placed at the top of the legend. Here, the Water and County layers obscure the Landmarks and Highways layers

• To change the order in which a layer draws, click the layer in the legend and drag it to a new position (up or down). You can also reorder layers by right-clicking the active layer, then clicking Move Layer. With this method, you can move the active layer up or down or move it directly to the top or bottom of the legend.

Layer Properties dialog• The Symbols tab is where you change the

method, style, color, and size of layer symbols. ArcIMS offers three ways to symbolize your feature data: one symbol, graduated symbols, or unique values. Using options in the Labels tab, you can display text labels for layer features based on an attribute field. You choose the attribute field, font, style, size, and label text effects for each layer.

• The General tab displays information for that layer (data source location and type). In this tab, you can change the name of a layer as it displays in the legend. You can also set a scale factor for a layer, so that features display or don't display based on the map's scale.

Single symbol

• If you like, you can use custom images for point and polygon feature symbols. The images must be GIF or JPEG files, and they can be modified only in a graphics program, not in Author. In the legend, custom images will be sized to 16-by-16 pixels. To use custom images as symbols for point or polygon layers, you will need to specify in the Layer Properties dialog both the absolute path to where the files are stored

You may have to edit your Web server configuration file and add another virtual directory to the list.

Unique symbols• For example, suppose you have a layer of 100 pizza

restaurants. Conceivably, you could use a unique symbols legend to display these features by restaurant name. You would end up with 100 different symbol types if every restaurant has a unique name. More appropriately, you could use unique symbols to display the pizza places by their neighborhood location. You will then create fewer symbols that have more implied meaning. You can change the style type (point marker, line style, or polygon fill pattern) of the symbols used to represent features. For point and line layers, you can also change the size of all your feature symbols. Additionally, the label displayed in the legend can be changed.

• ArcIMS can display features with a number of methods when you use a unique symbols legend. Bountiful harvest, pastels, and minerals are three predetermined color schemes.

Graduated symbols• ArcIMS uses the Equal Interval classification method to divide features

into classes. The Equal Interval classification method divides the range of attributes into equally-sized subranges. You cannot customize the range values in Author. As you will discover later, you can change these values from within the map configuration (AXL) file.

• You can also display ranges based on a start and end color. For example, in the map above, census tracts in the lowest class for median property values are displayed in yellow (the start color) and tracts in the highest class for median property values are displayed in red (the end color). Tracts with property values in between are displayed in colors between yellow and red.

• You can also symbolize a layer using differently sized line or point symbols (e.g., represent census tracts with low median property values with a 5-point circle and tracts with high median property values with a 20-point circle).

• By default, when you use a graduated symbols legend, the label for each class (the text that appears in the legend) is the same as the class range values. You can change the labels for the classes if you like.

Graduated-symbol map

Exercise – Add data using Author

• You will need data from U drive. Create a map using Author.

• Right-click on folder which contains the shapefiles to make it as a favorite folder in Catalog.

• Add data and change symbol to reflect the data nature

• Save data in U drive.

ArcXML structure

• Like HTML, the ARcXML use element tag. Forward slash (/) to end an element. Some elementsNote how the elements are defined. Their names are in uppercase letters and surrounded with angle brackets (this format is usually called the element tag). Some elements have both opening and ending tags, while others, like SHAPEWORKSPACE, have only one tag. Note the forward slash at the end of the SHAPEWORKSPACE and DATASET elements

Exercise

• Open tn_physiography.axl from Notepad on your computer. Answer the following questions (Do not save this file if you somehow modify this file. You’d better copy this file to your directory)

• 1) What version of ArcXML is being used?• 2) Where is this project stored?• 3) What map units are being used?• 4) How many layers the project contain?

Defining the map presentation

• about the tools ArcIMS Author provides for exploring map data

• how to set a scale range for a layer • what a scale dependent renderer is • how to create complex feature symbology

using group renderers • how to add text labels for layer features to a

map • how to define stored queries and geocoding

properties for maps • how to author a map in ArcIMS Manager

Tools for exploring data• Identify - When you use Identify, the attributes for all the features

located at the same point within a search tolerance are displayed. For example, if several features in the same layer are close together, the Identify Results window may display information on all nearby features. When this happens, click one feature in the left panel to see its attribute data.

• Map tips – MapTips allow you to see an individual attribute value as you pause the mouse pointer over features in the map. Only one MapTip field may be set per layer

• Find – You can use the Find tool to quickly find a feature based on a string (text) attribute. Find searches the string fields of layer attribute tables and returns the records for features that meet the search criteria. In the Find dialog, you enter the text value for which you want to search (you don't need to enclose the text with quotes), keeping in mind that Find searches are case-sensitive. You can enter a partial value and Find will still return results (e.g., typing "Afgh" will find Afghanistan).

Advanced properties for map display• When you're preparing maps for publication on the Web, you'll want

to keep your end-users in mind. What functionality will they find helpful? How can you enhance the map display to make it more attractive and understandable?

• When you're preparing maps for publication on the Web, you'll want to keep your end-users in mind. What functionality will they find helpful? How can you enhance the map display to make it more attractive and understandable?

• In ArcIMS Author, there are many ways to customize your map display to meet the needs of your end-users. In Lesson 1, you saw some of the ways you can change the symbology for layers in your maps. In this topic, you'll learn more advanced layer display techniques that will help you design maps appropriate for your audience.

• You can do more in Author, however, than just define the appearance of the map. You can also prepare for the functionality you want your Web site to include. You can define your map configuration file so that end-users of your Web site will be able to search for features on the map and even type in an address and have that address display as a point on the map.

Descriptive Names/Scale/Transparency• Most of the data layer’s name are only meaningful to the creators

of the layers. You need to provide a descriptive names of the layers so that end-users will have idea what the layer is about.

• Set explicit scale factorsWhen you're displaying several layers on a map and you don't want the display to be cluttered, you can set explicit scale factors for layers. That is, you can set the scale range in which a layer displays. Outside of that range, the layer will not be visible on the map. You can set the minimum scale, maximum scale, or both. Setting a scale range writes two attributes to the map configuration file's LAYER element: minscale and maxscale.

• the General tab will include a transparency slider bar, which allows you to adjust the visibility of an image layer (or Image MapService if applied using the Layer Properties button in a Java viewer or ArcExplorer Java Edition). Using the Transparency slider bar, you can adjust the transparency of the image layer from 0 to 100 percent transparency. The default value is 0 percent (the image is not transparent).

Scale Issues• Scale factors are a good way to produce a

map that has the appropriate amount of detail at a given scale. If you have a detailed layer, you may not want it to turn on until a user zooms in. For example, you may not want a city streets layer to draw when the extent is zoomed out to cover the entire region

• In this example, street features are visible only when the scale reaches 1:5,000,000. Cities are not visible until a 2,500,000 scale is reached

• To change the minimum or maximum scale factor, you can go through the steps again or remove the scale factor by right-clicking the layer and choosing Remove Scale Factor.

• When a layer is not visible due to a scale factor, the layer name is also removed from the legend.

Scale dependent renderers• A scale factor determines the visibility of a layer

based on scale. A scale dependent renderer changes the symbology of a layer based on scale.

• To set a scale dependent renderer, you work in the Layers tab (next to the Legend tab). In the Layers tab, select the active layer, then click a renderer to edit. Click the Set scale dependent renderer button to set the maximum scale range, minimum scale range, or both for this renderer. You can add more renderers to the Layers list by clicking the Add another renderer button. After you click this button, the Layer Properties dialog opens, where you can create the symbology you want. Set a scale range for the new renderer using the Set scale dependent renderer button.

• Setting a scale dependent renderer for a layer adds the SCALEDEPENDENTRENDERER element in the map configuration file for that LAYER element. To remove a layer's scale dependent renderer, click the Clear scale dependent renderer button in the Layers tab.

Group Renderers

• Now things get really fancy—you can add additional renderers to a layer to create complex symbology for certain features and make them more attractive or distinguishable. A common usage of group renderers is to draw a road layer twice: once with a wide line, and again with a narrower line of a different color to display a cased road. If you have turned on labeling for a layer, the labels will always appear above all group renderers in a layer

• When creating group renderers, you may need to move renderers up or down in the Layers list. For example, you would want the thick line renderer on the bottom and the thin line renderer layer on top. Group renderers add the GROUPRENDERER element to the map configuration file and will apply to all features in the active layer.

Add labels• Labels are text added to a map that describes the features in a layer. The

text source for labels is one of the layer's attribute fields. You set labeling for a layer using the Labels tab in the Layer Properties dialog

• ArcIMS uses an algorithm that places each label in the best possible position. This algorithm will also resolve label conflict so that no labels will overlap

• Labels add either a SIMPLELABELRENDER or VALUEMAPLABELRENDERER element to the map configuration file, depending on how you assign them to your layer.

• You can label line features with five different highway shield styles: Interstates, US States, Mexican, Oval and Rectangle.

• In the Layer Properties dialog, choose a numeric field for labeling, then click the Use Shields button. You can use the same highway shield for every line in your layer or different shields based on values within an attribute field. You can then choose a different shield type for every unique value in the chosen attribute field.

Duplicate line lables

Shield properties

Using your own custom highway shields You can incorporate your own highway shields in your map display, but not directly through the ArcIMS Author interface. You can manually add the RASTERSHIELDSYMBOL element to the map configuration file to point to your own GIF or JPEG shield image. You can also add attributes to determine the database field and the label font. For more information, consult the ArcXML Programmer's Reference Guide.

Stored Query• Creating stored queries for your maps allows end-users to ask questions

and get information about the features on the map. In other words, they can query the spatial database. A stored query in ArcIMS takes the SQL (Structured Query Language) syntax burden off the end-user and allows you to define a concise or complex single-parameter statement that the end-user will refer to by name.

• To create a stored query, click the Stored Query button in ArcIMS Author and name the stored query when prompted. This will be the same name used to identify the query in the Web site, so be sure to make the query name appropriately descriptive.

• Use the Stored Queries dialog to construct an SQL-like expression. While you're building the expression, a popup window may appear asking if you want to see only the first 100 sample values or see all values. Test the expression by clicking the Execute button.

• If the query works, you complete the stored query by substituting a variable for the value and saving the query with the unique name. This will add a STOREDQUERY element to the map configuration file.

• When the Web site is up and running, end-users clicking the Search button will access your stored query and can supply their own value for the variable.

Geocode process• Address geocoding is a process that allows end-users to locate a

point on the map based on an address they enter. To include address geocoding functionality in your Web site, you must add a street reference layer to the map. ArcIMS Author does not perform address matching. Instead, it writes the necessary information for address matching to the map configuration file.

• To enable geocoding in your Web site, you add the street reference layer to Author (or ArcIMS Manager), then set geocoding properties for it. In the Geocoding Properties dialog in Author, you choose an address style and the corresponding fields in the street attribute table for each address component that the address style requires (required components are indicated with an asterisk). Geocoding performance and processing depend on the size of your street reference layer.

Geocode - 2• ArcIMS uses the same geocoding engine and supports the same

address styles as ArcView GIS 3.x. For information about the address styles supported by ArcIMS, consult the Using ArcIMS reference or ArcIMS online help. When you add geocoding functionality in Author, several new embedded elements are added to the map configuration file (GCFIELD and GCSTYLE) and new index files (identified with GCI and XRF extensions) are created. For an ArcSDE street reference layer, you will be prompted to save the index files to a directory. By default, the index files will be saved to a temp directory. For shapefile street reference layers, the index files are stored in the same folder with the source shapefile.

• After you set the geocoding properties, end-users of your Web site will be able to click the Locate Address button, enter an address, and the point representing the address will be geocoded and displayed on the map.

Exercise

• Use data from learnarchims\author\lesson2\data and Mrn_rds and Mrn_rvs (data from Marion, Indiana Census TIGER 2000 data)

• Symbolize the layers• Add scale dependent renderer for

features/Labels• Identify