Map Editor User Guide - Navigation

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This section describes the various ways of navigating around maps in Map Editor.

Zooming

To zoom into and out of a map, use the zoom tool and drag out a rectangle to zoom the view to that area. If you hold down the control key while dragging, the view will zoom out instead of in (think of the window being shrunk onto the rectangle). If you click rather than dragging out a rectangle, the view will zoom in or out by a factor of 1.5 about the point you clicked. You can also use the "Zoom in/out" commands to zoom about the centre of the view.

To fit the whole map into the window use the "Zoom to Fit" command.

Panning

To pan the map, use the pan tool. Click on a point on the map and drag it to where you would like it to be. You can also use the "Pan left/right/up/down" commands to pan by half the size of the view. The pan tool works in plane coordinates. That is, it simply slides your view over the (flat) map. If you are viewing the world with a projection, the pan tool will not recentre the projection. To do this, use the Centre tool.

Changing the Centre of Projection

The Centre is only available when a map projection is being used. It changes the centre of projection to the point where you click. For example, if you are viewing the world with an Orthographic Azimuthal projection, what you see looks like a view of the Earth from space. Using the pan tool will simply move the globe around the screen. Clicking on a point with the Centre tool will change the projection centre to thtat point, effectively rotating the globe so that you are looking directly at the point. The effect may be different with other projections. For example, cylindrical projections will ignore the centre latitude but will honour the longitude centre. You can also change the centre of projection in the "Set Projection" dialog.

Zooming to a Location

If you want to view a specific location use the "Zoom to Location" command. This shows a dialog where you can type the location's coordinates as well as the width of view. You can choose a different coordinate system for entering the location. For example, on a world map using latitude/longitude coordinates, you can enter locations in State Plane coordinates.

The "Zoom to Location" Dialog

Using the Overview Map

If you have an overview map defined, you will see your current view as a grey rectangle in the overview window. You can drag this rectangle in order to change your view.

Using a Gazetteer

Map Editor provides a gazetteer function which lets you quickly search for features and zoom to them. Selecting the "Gazetteer" menu item from the View menu displays the gazetteer dialog. Choose a gazetteer to search from the drop down list, type a search string into the text field and press the "Query" button. Any matches from the gazetteer will be displayed in the list below. You can select an item from the list and press the "Show" button to zoom the view to the item.

The Gazetteer dialog