New England SPARROW Data Viewer
2. Changing the map extent and scale
Most of the tools in the Toolbar along the left side of the Viewer are used to navigate in the Map Display.
The tool allows you to zoom into an area to view more detailed information. With the ZoomIn tool selected, the ZoomIn cursor in the Map Display can be placed over a point of interest and clicked to zoom in, centered on that spot. The same tool can be used to define a rectangular area that you would like to see displayed in the Map Display. To do so, place the cursor in the Map Display on the upper left corner of the box you would like to define, and drag to the lower right corner of your rectangle.
You can also change the Map Display to zoom out to view less detail using the tool in the same manner as the ZoomIn tool (click once or drag a box). When changing the zoom scale factor with the Zoom tools, notice that the scale of the map is updated in the scale bar beneath the Map Display.
The tool allows you to view areas, at the current scale, not visible in the Map Display that are within the immediate perimeter of the displayed area. To use the Pan tool, place the pan cursor on the map and press and hold the left mouse button, dragging the cursor in any direction. The pan arrows on the border of the Map Display can be used to provide a fixed pan in the direction shown by the clicked arrow.
The map can also be panned by using the Overview Map. The current Map Display's extent is shown in the Overview Map by a box outlined in red. When the mouse is placed over this red extent box, the mouse cursor will change to a four directional arrow icon. Press and hold the left mouse button, dragging the cursor and the extent box to a new location on the Overview Map. The Overview Map pan is especially useful for panning to areas not immediately bordering the current extent of the Map Display.
The tool will zoom the map to the extent of all the layers presented in the Viewer.
The and tools allow you to change the map extent backward or forward one display.