South African Coastal Information Centre (SAcoast) web map service (wms)
Acknowledgements
This help system is an adaptation and extension of the Geocortex Compass Tutorial/Help. Geocortex kindly and freely provided us with their tutorial system “Geocortex Compasss” for adaptation and this is gratefully acknowledged. Both Geocortex and the South African Coastal Information Centre Maps use similar technology with respect to ARC IMS and Moximedia IMF technology based on Java Server Pages. The assistance and support from Moximedia in developing these pages is also acknowledged with gratitude. These two Canadian companies have been wonderfully supportive in our efforts to develop web mapping services for environmental management in South Africa.
Using this Tutorial
This tutorial is built around html (hypertext mark-up language) that is driven by Cascading Style Sheets (CSS). This makes it easy to maintain and very easy to change the look and feel of the tutorial for all of the different map services we host, since we do virtually no change to the html but can generate rather different looks to the web-pages. Nevertheless the basic structure is identical in that the webpages have a forward and backward navigation and between these buttons is a Home or Index page which provides a description and link to each and every page in the tutorial. So what does this mean?... well very easy navigation. Both the Previous/Next buttons and the index or home page are situated at the top and bottom right so you can go through the material linearly which is the way we recommend when you first use this site. Once you have completed going through once and wish to check on how you use a particular function you can then use either the index/home page or the Table of Content on the left hand side and this will take you directly to that particular page. At the bottom of each and every page is direct link to the SAcoast maps, the SAcoast main web-portal and an email contact should you be experiencing problems. If this is not easy every part of the website where there is a link will provide a “hover” with pertinent information and in most cases a subtle colour change will occur.
Once you have completed this easy to use and comprehensive Tutorial we think you will find the Web Map Service easy to use and hopefully useful. If you have comments or suggestions there is feedback via the bottom of each of these pages plus directly from the map pages (in the About Section and from the Layer section). We look forward to hearing from you.
Cheers
Richard Knight
(Principle Developer of the SAcoast Web Map Services)
International Ocean Institute southern Africa
c/o Department of Biodiversity and Conservation Biology
University of the Western Cape
Private Bag X17
Bellville 7535
South Africa
Phone 27 + 21 + 959 3940
Fax 27 + 21 + 959 1237
Introduction to Internet Maps
Internet maps have much in common with traditional paper maps, with a few important differences.
This tutorial will show you how to use interactive Internet based maps. After this tutorial you should be able to use SAcoast successfully; even if you have no prior knowledge of GIS. The basic tutorial will probably take about fifteen minutes. However, in less than five minutes you can have the background required to successfully navigate a SAcoast map.
First, we'll cover two basic GIS concepts you need to know. Then we'll introduce you to the tools and methods that you'll use to navigate around the map and ask it questions.
This section covers the two basic GIS concepts you need to know to effectively use SAcoast maps.
GIS Concept # 1: Features have attributes associated with them.
/ Imagine a tree. How would you keep track of and communicate information about this tree to other people who need to know all about it?/ You might use a database to keep track of what species it is, how old it is, how tall it is, how healthy it is, and any other attributes that are important. This tree is one record in a database. We call each category (i.e. tree height) a field.
/ Now imagine a grove of trees that you need to keep track of attributes for.
Because we are now dealing with more than one tree, it becomes relevant where each tree is so we know what information relates to which tree. /
/ We map the location of each tree and identify which attributes belong to which tree. This is the foundation of GIS. A GIS tells us where something is and what it is. Computers are synonymous with GIS, and using a computer we can have hundreds of fields (different attributes) for millions of records (trees).
You will be able to examine the attributes of features as you navigate SAcoast maps.
GIS Concept # 2: Information is separated into layers.
We can also have other layers of information in our GIS. Our information on trees would constitute one layer of information. We could also have a layer with rivers and a layer with soil types. Any information can be represented as a layer.
/ A map represents the landscape in an artificial way. Vector layers represent features in one of several ways:
Points:
A point is good for representing information in which it is necessary to show where a feature is, but its physical shape is not important (i.e. trees in the old growth tree layer).
Lines:
A line is suitable to represent many real world features (i.e. the rivers in the river layer).
Polygons:
Don't be intimidated by the name. It is really just a solid multi-sided shape. When you see a polygon, remember that everything inside the boundary has the attributes associated with the record. (i.e. soil types in the soils layer)
You might hear people talk about coverages, themes, or shapefiles. All these terms are other names for layers of information.
With individual layers we can conduct analysis between layers and only display layers of interest.
As you work with SAcoast maps you will be able to turn different layers on and off as you desire.
Getting Familiar with the SAcoast Map Viewer
We suggest opening another session of your Internet browser and loading an actual SAcoast map. This way, as you go through the tutorial you can practice what is being explained. You can open one SAcoast Map using the link at the bottom of this page.
Please note that this is a Generic Tutorial not all SAcoast maps will have all features enabled. Each SAcoast map does have a dynamically generated help that is specific to that particular Map Service and is accessible from the Function Tab Bar.
When you open a SAcoast Map Viewer through your Internet Explorer browser, you will see a new window that looks similar to the example you see here.
The main window is the Map Window. This is where the map is displayed (on the right hand side). Beside it is the Information Panel (on the left hand side) , which displays information about the map and lets you work with map layers. Specifically, the Information Panel displays the legend, visible and active layers, and provides information about the map.
At the top of the viewer you can see the Function Tab Bar and the Toolbox. You will use the Function Tab bar, the Toolbox, and the Extended Toolbox to navigate around the map, ask questions of it, and otherwise interact with the information.
Exact scale, active tool and active layer information are all found below the map window (in the beige panel)
If you are feeling lost already... don't worry. Everything will be described in depth in the next few pages.
Function Tab Bar
Below is the function tool bar options
About
ABOUT
The About tab provides general information about the map. Information is displayed in the Information Panel, and may include details about the purpose of the map, as well as the organization that deployed the map.
Layers
LAYERS
The Layers tab displays a list of available layers in the Information Panel. If you wish to turn layers on or off, or make a layer active, then display the Layer List.
Legend
LEGEND
The Legend tab displays the current map legend in the Information Panel. The map legend shows you the symbology of layers.
Refresh Map
REFRESH MAP
If you have elected to switch off the “automatic refresh” in the layer list this tab bar will refresh your maps with the latest map layers that you have selected by the tick box.
Bookmark
BOOKMARK
Bookmarks are pre-set map locations that zoom you to a location on the map but do not alter the layer display. You can define your own personal Bookmarks if your have set your browser to accept cookies.
Find Location
FIND LOCATION
This will provide a rapid means to find locations and zoom to them based on
A drop-down menu of places/objects
Spatial Bookmarks
Latitude / Longitude Coordinates
Select
SELECT
The select tool is used for reporting and is only available for certain layers. When you click on the map with a select layer active, the features at the location selected will be displayed in the left window. The name of the active select layer is displayed in the status bar under the map. To set a different select layer, open the layer folders window using the LAYERS tab above, and click the select icon beside the layer that you want more information about.
Map menus
MAP MENUS
This provides a list of all Map Services available from the South African Coastal Information Centre
Help
HELP
This will open dynamically generated online help for each specific map service as opposed to this page which is a generic help/tutorial
Please click on any of the options in the above function tool bar for a pop-up explanation of that particular function. (You will need to ensure that you have enable pop-ups in your browser)
Toolbox
Please click on any of the options in the above default toolbox for a pop-up explanation of that particular function. (You will need to ensure that you have enable pop-ups in your browser). At the onset please note that the Zoom in tool is the default tool and is automatically set and this is indicated by the redbox that is drawn around it. All tools that require another input like clicking on the map to zoom in when selected a red box will be drawn around them.
Index
INDEX MAP
Choosing the Index Map tool displays a map that gives the main map context. An Index Map can be used to stay oriented as you zoom in and out.
Zoom_in
ZOOM IN
With the Zoom In tool you are able to zoom in by clicking on a location or by dragging a box to define a particular extent.
Zoom_out
ZOOM OUT
To zoom out on a map, pick the Zoom Out tool. Define the extent of the area that you wish to zoom out to by clicking on a location. This zoom will work in prescribed zoom intervals.
Zoom_full
ZOOM TO FULL EXTENT
The Zoom to Full Extent button zooms you to the full extent of the map. The full extent is often the extent of the map displayed when the viewer is initially launched.
Zoom_back
ZOOM BACK
The Zoom to Previous Extent button allows you to jump back to your last map extent. Note that this function remains inactive until you change extents.
Pan
PAN
The Pan tool lets you navigate around the map. To move around the map hold the mouse button down while you drag the pointer across the map, whatever part of the map you grabbed, will end up wherever you release the mouse button.
Identify
IDENTIFY
The Identify button allows you to click a feature and see a list of its attributes. A layer must be Active, in order to be identified.
Drill
DRILL DOWN
The Drill Down map function identifies and outputs all the features that exist at a particular location. Features from all layers that are turned on are output, regardless of whether they are visible at the current scale.
Identify_radius
IDENTIFY BY RADIUS
The Identify by Radius tool allows users to get attribute information from a layer within a defined circle.
XY
INSERT XY LOCATION
The Add a Location to Map tool allows you to add a point to the map and display the Latitude and Longitude coordinates.
PRINT MAP
This creates an Adobe PDF document for map and map layout printing
EMAIL MAP
This sends your current map view as a PDF map or a JPEG/PNG image. You can also add comments to your attached map.
Tools_open
OPEN EXTENDED TOOLBOX
The Expanded Toolkit holds tools that are used for advanced functions for the map. These tools are typically used once a user has become comfortable with the basic navigation tools. The Expanded Toolkit includes tools that allow you to do select and buffer functions, annotate the map, save map views as session files and extract subset data from layers as Shape (ArcView), Excel (attribute data), and GML files
Extended toolbox
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