Help for Users of the Benthic Mapper Viewer
Using Benthic Mapper
Using the Benthic Mapper Viewer
- Select areas of the river to view
- Display maps of data and superimpose maps to view combinations of data.
- Access supplementary detail about some map features
- Measure distances on the maps
The data displayed in Benthic Mapper were gathered by the Hudson River Estuary Benthic Mapping Project.
Introducing the Benthic Mapper Viewer
The illustration below shows Benthic Mapper's Viewer (Graphical User Interface, or GUI). On the blue frame you will find the tools and buttons that operate Benthic Mapper. The window in the center is the map viewer. On any map displayed in the Viewer, click at the point from which you want to zoom in or out, recenter, identify (display detail) or measure distance.
The illustration shows all the features of the Benthic Mapper Viewer. Move the mouse around the illustration - wherever your cursor turns into a hand, hold the mouse still to display the name of the feature, or double-click for a description.
The Overview Map (small window, upper left hand side of viewer) shows a small map of the complete Hudson River Estuary. A red rectangle indicates the portion of the Estuary currently displayed in the viewer. The size and shape of this rectangle changes each time you resize or zoom the map.
Help (lower left side of viewer) will return you to this page.
When you click on the Interactive Tool Dropdown Menu (labeled Click on Map to:), a list drops down with a choice of five interactive tools:
Zoom In - Select the zoom in tool, then click a spot on the map (each click will zoom the map in by 50 percent). Another way to zoom in is to click on a point on the map, hold down the mouse button, and drag the cursor in any direction to outline a red box. The map will zoom in to display the box you have outlined.
Zoom Out - The zoom-out tool works in just the opposite fashion from the zoom-in tool: you can click on a point or you can drag a box. A larger box will zoom the map further out.
Recenter - Selecting the recenter tool enables you to recenter the map on a point you choose by clicking. It also functions as a panning tool: left click and hold the mouse button down, then drag the entire map up, down, or to the side. When you release the mouse button, the map will redraw on the new center.
Identify - The Identify tool provides further information about features shown on the map. After selecting the Identify tool, you must select a layer from the Active Layer menu found on the right hand side of the viewer frame, then click on the feature you want to identify. Information about the feature will appear in a table below the map. (Not all features have further information available.)
Measure - The Measure tool measures distances represented on the map, either in a straight line or along a specific route. A distance indicator in the upper left hand corner of the map viewer shows the Total distance measured and the length of the current Segment being drawn.
To find a distance between two points: Click once once where you want the starting point, move the cursor to the next point and click again. A red line will appear between the two points and the distance between them will appear in the Total field on the distance indicator. As you move the mouse, the distance in the Segment field changes to show the distance from the last point. To continue drawing the same line, add segments by clicking on points along the route. As you add segments, the total distance will be updated in the Total field.
Previous View returns you to the last map you displayed.
Zoom to HRE (Hudson River Estuary) makes the map in the viewer zoom out to the extent of the entire estuary.
Clear Selection clears items selected with the measure button.
Refresh Map updates a map according to the most recent changes you have made. Each time you check or uncheck a layer in the Active Layer menu, you must click Refresh Map to add or remove the layer and to view the revised map.
Checking a layer on the Active Layer menu makes it available for use with the Identify tool. To use the identify tool, you must activate a layer.
Layer List and Legend lists the data layers in the Benthic Mapper. Checking the box next to a layer and then clicking the Refresh button will make that layer visible. You can select more than one layer. (Certain layers' features will appear only when you zoom in to a certain scale.) About Layers and Maps gives detailed infomation on how Benthic Mapper's layers display together.
You must click the Refresh button every time you select or deselect a layer.
When the layer name shows in blue, it is linked to a Legend showing the meaning of the map symbols for that layer.
Pilot Survey Area - red rectangles outline areas of the river for which data is currently available in Benthic Mapper.