Map window

Functionality

A map window may display one or more raster maps, polygon maps, segment maps, and/or point maps. Maps that are displayed in a map window are called data layers. The legend of each map is automatically displayed in the Layer Management pane of a map window.

A map window can also display three images of a map list as an interactive color composite, or all maps of a map list as a slide show.

You can also create an Annotation Text object which usually contains the labels of a point, segment or polygon map. You can add multiple Annotation Text objects to a map window.

Furthermore, you can add grid lines and graticules as a layer to a map window.

A map window displaying one or more maps, annotation text layers, optional grid lines and graticules can be saved as a map view. Map views can be added to a layout which is used to make a final composition before printing.

To a layout, you can then add further annotation such as legends, map borders including ticks and coordinates for grid lines or a graticule, north arrows, scale bars and scale texts, texts (such as a title), boxes, bitmaps and pictures, and a page border.

A map window consists of a viewer which displays the map(s) and additional layers, a Layer Management pane, an overview window, a menu bar, a context-sensitive menu, a toolbar and a status bar. Besides displaying, you can also edit maps in a map window.

To open a new map window:

A new map window is automatically opened when you open a map:

open the File menu in the Main window, and choose the Open command, or
double-click a raster map, a polygon map, a segment map, or a point map in a Catalog.

Before a map is actually displayed, some display options have to be specified in a Display Options dialog box.

You can also use the Open Map button in the toolbar of the Main window, or use the Show command in the Operation-tree or the Operation-list. For more information, see also How to open objects or How to display maps and tables.

Tips:

If you like, you can choose not to show Display Options dialog boxes: use the Preferences command on the File menu in the Main window, and choose Map window, Display. For each map type, you can specify whether or not you wish to obtain a Display Options dialog box when a map is opened. If no Display Options dialog boxes are used, maps will be displayed with their default settings.
In the Preferences (Map window, Display, Position and Size), you can also specify a fixed size or a fixed position for all map windows to be opened.
To speed up the display of large raster map, for instance maps that have more than a few thousand lines and columns, you can create pyramid layers. For more information, refer to ILWIS objects : Raster maps - Pyramid layers.

To display multiple layers in a map window:

You can add several layers to a map window by using the Add Layer command from the Layers menu, or by clicking the Add Layer button in the toolbar of the map window. You can add a raster map, a polygon map, a segment map, a point map, a map list or an existing annotation text object to the map window.

When you add a map list to a map window, you can choose to display the map list as a color composite, or as a slide show.

To add grid lines or a graticule, you can choose the Add Grid Lines, or the Add Graticule command from the Layers menu.

For each new layer to be displayed in the map window, display options have to be specified. In the Display Options dialog box of maps that have an attribute table, you can choose to display a map by one of its attributes. Any layer that is added to a map window is also added to the Layer Management pane of the map window.

Layers that are added to a map window will be displayed on top of the other layers that are already displayed. When a map window already displays a raster map, you can only add another raster layer (or a map list) when the raster maps use the same georeference. You can use the Resample operation to transform a raster map to another georeference.

Tips:

For more information on adding layers to a map window, see also How to add extra layers to a map window.
To temporarily hide layers or to remove layers, see Map window : Layer Management.
For more information on working with layers, see How to use layers in a map window.

Displaying layers with transparency:

In the Display Options dialog box of a layer, you can specify whether a layer has to be displayed with a certain transparency. In this manner, you can display (partly transparent) thematic information on top of images, a shadow map etc. and view both types of information simultaneously.

First display a map that you wish to use as background (without Transparency).
Then, add one or more other vector or raster layers; you can select the Transparency check box in the layer's Display Options dialog box.

Click the following link for an Example of transparent layers.

Technically spoken, transparency is obtained by using the standard Windows method of AlphaBlending. The method is not available for Windows 95 or Windows NT. Transparent layers are thus only possible in Windows 98, Windows 2000, Windows ME or Windows XP; furthermore, the Display Settings of your screen must be set to 32 bit (True Color).

Mind:

It is not possible to display map views with transparent layers in a layout, nor to print any transparent layers.

To get Info on maps and attributes:

When you press the left mouse button at a position of interest in the map window, you will obtain information on a map and optionally of the attributes.

When, for example, a satellite image is displayed in the map window, you will see the pixel value at the current mouse position.
When a rasterized polygon map is displayed that contains for example land use classes, you will see the names of the land use classes.
Similarly, when pointing to a polygon, segment or point in a map window, the name or value of the polygon, segment or point is displayed.

To obtain information on a data layer it is necessary that the Info check box in the Display Options dialog box of the layer is selected. In the Layer Management pane, the layer will then be preceded by a small . By pressing the left mouse button in the map window, you will obtain 'Info' on the top layer of which the Info check box has been selected. When a map is shown by one of its attribute values, 'Info' shows the class name or identifier and the attribute value of this class or identifier.

When multiple maps are displayed, a search will be performed at the position of the mouse pointer through all layers (from top to bottom) that are displayed, and of which the Info check box has been selected. When in the first layer a class name, identifier, value or a color is found, it is displayed next to the mouse pointer. When an undefined value is found, the search continues in the next layer. If in a raster map no class name, identifier, value or color is found, a question mark is shown. If in a vector map no class name, identifier, or value is found, nothing is shown.

Tips:

You can increase or decrease the number of characters shown by 'Info' in a map window and in the map editors by setting the 'width' in the properties of the domain. The default width for a class domain is 15, the default width for an identifier domain is 6.
For value raster maps, it is advised to select the Interpolation check box in the Raster Map Properties sheet; you will then obtain interpolated value information on sub-pixel level.
To inspect the meanings and/or values of multiple maps and their attribute data, you can add multiple maps to a pixel information window.

Double-click action, e.g. to view/edit attributes:

When an attribute table is linked to a map or its domain (class or ID domain), you can double-click at a position of interest in the map window and directly view and/or edit the attributes as stored in the attribute table.

Double-click can also be used to edit the representation of the classes in a map with a class domain, and to open other maps, tables, (GIF) images, sounds or videos, etc. i.e. via an Action column in the map's attribute table.

The action that will be performed on a double-click is determined by the Double-Click Action command on the Layers menu.

Tip: For more information, see also Map window : functionality (advanced).

To zoom in and out on maps, and pan:

To zoom in on a map, you can use for instance the Zoom In command on the Options menu, or you can click the Zoom In button in the toolbar. To zoom in on a certain area or position, you can also use the overview window.

If you zoom in very deeply on a raster map and when the Text check box has been selected in the map's Display Options dialog box, the values or meanings of pixels will appear inside the pixels of your map.

When zoomed in, you can use the Pan command from the Options menu or the Pan button to roam through your map(s), or use the scroll bars.

To zoom out or to (re)display the entire map, you can use for instance the Zoom Out or the Entire Map commands on the Options menu, or click the Zoom Out button , or the Entire Map button in the toolbar.

If you wish to display a raster map without any zooming, you can use the No Zoom command on the Options menu.

To switch off Zoom In, Zoom Out, Pan or Measure Distance mode and return to normal pointing mode, choose the Normal command from the Options menu or click the Normal button in the toolbar. The mouse pointer will change back into a normal pointer. You can also press the Esc key or the Ctrl+N keys on the keyboard to return to Normal mode.

Tips:

The overview window provides an overview of the entire area of the maps that were added to the map window. You can use the overview window to quickly zoom in on a certain area, and it may help to orient yourself on the position of the area on which you zoomed in and that is currently shown by the map window.
For more information on zooming, see also Map window : toolbar, and/or Zoom In.

To change a representation:

If you are not satisfied with the current colors, hatching, line types, symbols, etc. of a map in your map window:

open the Display Options dialog box of the map and select another representation, or create a new one yourself, or
double-click the word 'Legend' of a map in the Layer Management pane, or
if you wish to edit the color etc. of a class in a map with a class domain, double-click the class or its color as listed in the Legend of the map in the Layer Management pane.

When the map window displays a map which uses a user-defined representation, you can also open Edit menu and choose Representation.

Depending on the domain used by the map, the representation Class editor or the representation Value/Gradual editor will be opened.

Tips:

When a map uses a system domain and a system representation, the representation cannot be edited. You can create a new, custom representation for the map through the map's Display Options dialog box.
For maps with a Class domain, you can also set the Double-click action to Representation (Layers menu); double-clicking in the window then allows you to edit colors directly.
For maps with a Bool domain, you can set the default colors for True and False through the Preferences command on the File menu of the Main window.
For more information, see also ILWIS objects : representations or How to use representations.

Other functionality:

The scale on which the maps in a map window are displayed can be set in the Scale control. The Scale control is by default located next to the toolbar.
To display certain layers only on certain scales, you can use the Scale Limit check box in the Display Options dialog box of a layer.
When the map window is displaying a raster map or a map list as a color composite, you can show the histogram(s) of the raster map(s) by using the Show Histogram command on the Options menu.
The distance and angle between two points in a map window can be measured by selecting the Measure Distance command from the Options menu or by clicking the Measure Distance button in the toolbar.
The background color of undefined parts in maps displayed in a map window can be changed by selecting Background Color from the Layers menu.

The color of the map window background itself, i.e. the space outside the map(s) displayed in a map window (by default dark gray), can be changed by adapting the Windows Display/Appearance Settings. On the Appearance tab of the Windows Display Properties sheet, choose another color for Application Background.

The size of a map window can be increased or decreased by selecting the Extend Window command from the Options menu.
The coordinate system or georeference used by a map window can be changed by selecting Coordinate System from the Options menu. This is useful to display map(s) with different coordinate systems.

To edit maps:

To edit maps you can start one of the editors. In raster, polygon, segment and point maps, you can edit the IDs, class names or values in these maps, depending on the domain of the map. You can insert new segments or new points with or without using the digitizer. You can check segments and polygonize them. Furthermore, in point maps, points can be moved to a new position; and in segment maps, the position of coordinates within segments can be edited.

Note: Dependent maps cannot be edited until you break the dependency links in the Properties sheet of the dependent map.

To save multiple layers as a view and to create a layout:

You can save the layers in a map window, their display settings, as well as the scale of the map window, and the position of the layers in the map window as a map view. Use the Save button in the toolbar, or choose the Save View or the Save View As commands from the File menu.

When a map view is opened later, all the layers in the map view are directly displayed in one map window without any display options being asked.

Furthermore, you need one or more map views if you wish to create a layout to print your map(s). To create a layout, choose Create Layout from the File menu in the map window. If the layers in the map window still need to be saved, you will be asked to do so. Then the layout editor will be opened. To a layout, you can add one or more map views, and additional annotation.