Map Windows and How They Work

Managing the Display Environment
 
 

The GeoMedia application consists of a series of windows. The application window contains menus, toolbars, and the GeoWorkspace. The workspace in turn contains data windows, map windows, and a single layout window. The map window is the client window in which you view and work with feature geometries, images, thematic displays, and labels. The content of a map window is referred to as a map view.

The map window’s legend, its view settings, and its display and window properties control the display of map objects within any map window. Map window contents are controlled by legends. Map window marginalia includes the legend, the North arrow, and the scale bar. The legend allows you to add and remove feature classes from the map window, change their display styles, reprioritize their display, and so on. The North arrow and scale bar are turned on and off from the View menu. They are dynamic objects that update to reflect changes to the map window. Map window properties determine how select set displays are handled and Display Properties allows you to define the nominal map scale.

The status bar at the bottom of the application window displays the current scale or view extents of the active map window. When working in the map window you have access to tools that provide measurements and coordinate readouts.

Map and data windows are linked so that changes made in one window are reflected in the other. The map and layout window may be linked in which case changes made in the map window are applied to the map design in the layout window.
 
 

Tip: The GeoMedia Help Topics can be accessed while you work in any type window. Hit the F1 key anytime you are working in a command dialog to get information about the command.

How Map Windows Work

Because GeoMedia is Microsoft Office compatible, its windows behave like windows in any other OLE compliant application. The map window icon appears at the left of the map window title, or in the upper left corner of a maximized map window. This icon contains a menu that allows you to control the map window. Depending on the current state of the map window, you can restore a minimized window; move, minimize, or maximize the window; and close the map window. You can also cycle through all open windows using the "Next" command on this menu.
 
 

Context Sensitivity

Context sensitivity is an important concept in GeoMedia. Context is determined by the window that has the focus; that is, the active window. A window becomes active and its title bar is highlighted when you click in it or on its title bar.

High-level context sensitivity is based on whether the active window is a map, data, or layout window. Some commands, such as most on the File, Warehouse, and Tools menus, are available regardless of the type of active window. However the contents of the Main Menu bar and the availability of commands on many menus vary as a function of the type of active window, as does the availability of toolbar buttons.

While menus and menu options are determined by the contents of the active window; data, a map, or a map layout, some commands apply specifically to the active window and some affect all open windows. For example, the Map Window Properties command is only available on the Window menu when a map window has the focus. When you run the dialog, the changes you make apply to the particular map window that is active. The same is true when a feature class is added to a legend. It is only displayed in the active map window. However, a modification to a feature class will cause an update to every open window displaying that feature class in the GeoWorkspace.

The Window menu on the Main Menu bar contains tools for creating new windows, opening the layout window, cascading or tiling windows and for activating windows. This menu lists all open windows in the GeoWorkspace. A check mark indicates which window is active. The final command on the Window menu, "Map Window Properties" is discussed below.

Multiple Windows

You can have many map and data windows open in the application window. Its specific view settings and properties determine each window’s behavior. Each window has its own legend, North arrow, and scale bar. This allows you to view a collection of different features from different warehouses in each window, or to view the same feature in each window at different scales. One map window could display an entire project area, whereas a second could display only a specific zoomed-in area.

While each open window is independent of the others in terms of legend content and view settings, they are also linked to one another when they contain legend entries for the same feature class. Selecting a map object or objects in one map window causes the same feature to be selected in all map windows that contain that feature. A select set is a map object or a group of map objects "selected" in the map window, usually by clicking on them or by placing a fence around them. Select sets are covered in Chapter 15.The way each window displays a select set is determined by its map window properties (discussed in material to follow).

A new map window is created with the Window > New Map Window dialog. You can enter a map window name, and select either an empty legend or named legend if any are stored in the workspace.

There are several ways to move between open windows. From the Main Menu bar you can select the Window menu. The bottom of this menu contains the names of all open windows. Click on the name of the window you want to activate. If more than nine windows are open, this menu will contain a More Windows entry. Use this command to view all window names. Windows are selected interactively by clicking in them.
 
 

The View Menu

View settings are interactive tools that allow you to zoom in or out of the map window and to move the display around. In the map window you can zoom in, out, or to nominal map scale. You can pan the map to reposition it in the map window. All objects or selected map objects can be fit to a view. The contents of the map window can be refreshed updating the view with any changes made in the source warehouse. The display of the legend, North arrow, and scale bar can be turned on or off, as can the display of toolbars in the application window.

The map window’s legend, its view settings, and its display and window properties control the display of map objects within any map window. The legend allows you to add and remove feature classes from the map window, change their display styles, reprioritize their display, and so on. The North arrow and scale bar are turned on and off from the View menu. They are dynamic objects that update to reflect changes to the map window. The status bar at the bottom of the application window displays the current scale or view extents of the active map window.
 
 

Zooming and Fitting

The map view commands allow you to adjust the display in each of your map windows. All zooming and fitting tools are found on the View menu on the Main Menu bar, and are accessible on the Standard toolbar, with the exception of Zoom Previous. You can interactively zoom in to see more detail in the map window, or zoom out to see more of the map. Select the appropriate command from the View > Zoom menu and click in the map window. The point you select becomes the center of the new view extent.

To zoom into a specific portion of the map, click on View > Zoom > In and place a fence around the area to be zoomed in on. Click on the upper left corner of the area and (keeping the mouse button depressed) drag the fence to the lower right corner. You can also zoom a predefined amount by selecting Zoom > In then single clicking where you want the map to center in the window. The zoom tools remain active until you terminate them by pressing the Escape key, or by clicking on the Select Tool on the Selection toolbar. You can also zoom in or out to the nominal map scale. View > Zoom > To Nominal Map Scale displays the map window at the nominal scale defined on the Display Properties dialog. View > Zoom > Previous backs a map window out to the last view scale it had.

Panning in the map window allows you to interactively grab a map and drag and reposition it in the view without rescaling. Select View > Pan, click in the window, and move the map while holding down the mouse button. This command must be explicitly terminated by clicking on the Select tool or by pressing the Escape key.

You can fit all map objects in the view, or you can fit a select set. Fitting involves sizing the window content in such a way that all map objects can be displayed in the map window. In contrast, View > Fit Select Set centers and rescales only the select set display according to the parameters set in the Map Window Properties dialog.
 
 

Map Window Pop-Up Menus

Like menus and menu contents, pop-up menus produced by a right mouse click are always determined by the location of the cursor when you click, and by map or data window objects selected, if any. The pop-up menu that displays when the right mouse button is clicked in any part of the client area of a map window (except on a legend, North arrow, or scale bar) contains commands for starting a new query or taking a snapshot of the window. From this menu you can toggle the legend, North arrow, and scale bar displays on or off depending on the current status of each. Attribute data for selected features is viewed using the Select Set Properties command. You control how select set features are displayed using Map Window Properties. The display scale of features in the map window is set with the Display Properties dialog available on this menu.

Note: Right clicking on the legend, North arrow, or scale bar produces different pop-up menus. The legend menus are discussed in Chapter 11. North arrow and scale bar menus are covered later in this chapter.

GeoMedia windows are used to view data and graphics. Map windows are used to view graphic data or geometry. Data windows give you access to the attribute, or nongraphic, data contained in database tables. Hardcopy output is created in the layout window.

Because of GeoMedia’s Microsoft Office compatibility, many of the window manipulations available will be familiar. Multiple windows can be opened, tiled, or cascaded. The map window itself can be maximized, minimized, resized, and moved. Window toolbars can be added to the application or can be turned off. When on they may be docked in the application window or they may float over the window.

There are many tools in the map window with which the display environment can be controlled. Window background, highlight, and select colors can be customized. Zooming in, zooming out, and panning can create various views of the data. Coordinate display, legend display, North arrows, and scale bars can be added and deleted from the window, as can map objects. The particular tools and options available are context specific and will vary as a function of the active window or selected map objects.

In the workflow that follows you will work with some of the tools that control the map window and its contents. Start by opening a new GeoWorkspace. Open a connection to the parcel database and to the tgr05143 warehouse. Add feature classes assessor_data and tiger_boundary to the map window.

1. Resizing windows. Moving the cursor to the borders of a window changes it to a double-headed arrow. With this cursor, keeping the left mouse button depressed, you can drag the border to change the size or aspect of any window.

graphic with hgm8_1.gif.
 
 

1. Tile the map windows. On the Main Menu bar, click on Window > Tile Vertically. The following illustration shows two map windows with different views.

Map Window Properties

Map window properties include the map window name, settings that control how the map window displays select sets and an option to override select set display parameters. The Map Window Properties dialog is accessed from the Window menu on the Main Menu bar or by right clicking in the active map window. The Properties dialog always updates the active map window. There is an individual set of properties for each open window.

The first field in the dialog lets you name the window. Map windows can have user-defined names, or you can let them default, in which case they will be named MapWindow1, MapWindow2, and so on. The "For items in select set" portion of the dialog sets the display options for select sets. When "View at current scale" is selected, the select set is highlighted in the map window but the scale and position of the display remains unchanged.

The "Center at current scale" option maintains the scale of the display but pans it such that the select set is centered in the map window. "Fit and zoom out" first pans to center the select set in the map window. The map window is then rescaled by the value in the spin box. If a map object "fits" in the map window at a scale of 1:5000 and the zoom out percentage is set at 200, the final map view will display at a scale of 1:10000. You can select a percentage or you can type the percentage in the text box. The zoom out default setting is 105%.

Using a combination of these view settings in several map windows allows you to simultaneously see the feature class you are working with at a variety of scales, as shown in the following illustration. You can view the entire map extent in one window as you set a second window to zoom and center when a map object is selected.

The "View at current scale only" checkbox is an override of the "Center at current scale" and "Fit and zoom out" options for selections made in the current window. Selecting the "View at current scale only" option is intended for use in situations such as editing workflows, when you want the map window in which edits are being made to temporarily remain at the current scale.

The Map Window Properties dialog allows you to name a map window and to control how features are displayed. This is particularly useful when your workflow involves multiple map windows. Map Window Properties allow you to specify different zoom and center options for each open map window. This functionality ties back to the idea that an action taken in any open window is reflected in all open windows. By adjusting the map properties, you can maintain different "views" of your select sets as you work.

You have three viewing options in the Map Window Properties dialog: "View at current scale," "Center at current scale," and "Fit and zoom out." You will review the implications of using each of these options in the following exercise.

For this exercise you need access to the GeoWorkspace HGM8IGM7.gws and the Texas.mdb warehouse. The workspace is set up to connect to the Texas warehouse located in the C:\warehouses directory. If your warehouses are stored in a different location, open the IGM7 HGM8 workspace and edit the connection path to point to the correct location. See Chapter 3 5 if you need more information on editing connections.

Display Properties

The settings on the Display Properties dialog are primarily linked with preparation for hardcopy production. Feature displays change dramatically as a function of display scales and legend settings. Symbology settings that allow displays to change based on the view scale are often well suited to the analysis portion of your workflow. Those settings are often ill suited to map creation. Plot displays generally require settings that insure that the features display correctly at a nominal map, or plot, scale.

Note: For pre-4.0 GeoMedia users, this dialog replaces the functionality that was found on the Paper Space tab on the Define Coordinate System dialog.

Display Properties, shown below, allows you to fix display scale and adjust your map in the map window to that scale. It allows you to work with your map contents at the scale at which they will be plotted.
 
 

graphic hgm8_2.gif

Caption: The Display Properties dialog.

The "Display scale" field is associated with the active map window display. This field will contain the current map scale and will change when you zoom in or out. It can be used to zoom to a specific scale. The drop-down list contains a number or predefined scale factors from which you can select or you can key in a scale. Clicking the Apply button causes the map window to zoom to the scale entered here.

The "Nominal map scale" and "Set all legend entry styles to" parameters are important in the plotting portion of your workflow. These settings are covered in more detail in Chapter 24. When transferring the data from the map window to the layout window for hardcopy production, a plot scale is used to define the ratio between the ground units in the map window and the paper units in the layout window. This ratio is referred to as the nominal map scale. Nominal map scale is the scale at which line width, text, and symbols are displayed at their true point size. For example text defined by an 8-point font will display at the 8-point size, or 0.110 inches, when the map window scale is equal to the nominal map scale.

Note: Nominal map scale is typically set to the scale you work at most frequently. It’s value defaults to 1:50,000. When you set the Nominal map scale value, the warehouse connections are closed and reopened so the coordinate system can properly scale and project all the legend entries.

You will frequently define a feature’s display as "Size remains constant as display scale changes" on the Style Definition so that features do not rescale as you zoom in and out of the map window. This setting, along with nominal map scale, affects how features are rendered when transferred to the layout window. "Size remains constant as display scale changes"overrides the nominal map scale rule in both the map and the layout window. The result is that features with this setting enabled will be inaccurately rendered when they are inserted in the layout window. To insure that the relationship between the map and layout window is truly ‘what you see is what you get’ this setting must be turned off and " Size changes as display scale changes (true at nominal map scale)" should be on. The Display Properties dialog allows you to apply either selection to all feature entries in the map window legend.

The "Rotation angle" and "Units" portion of the dialog allow you to rotate the map window. You can select one of the values in the drop-down list or you can type in a value. The rotation angle is calculated in the units selected in the "Units" field.
 
 

Scale Bar

The scale bar is a dynamic object marked in intervals of ground units representing the actual distance on a map. Like the scale or view extents display on the GeoMedia status bar, the scale bar is updated whenever zooming or fitting features changes the scale of the map window.
 
 

When the scale bar is first displayed, it uses the "Distance" units defined using Tools > Options > Units and Formats. These units can be changed in the Scale Bar Properties dialog, as can other display characteristics. A scale bar can be dragged and dropped anywhere in the map window.

Each map window can have only one scale bar in its display. By default, the scale bar is not displayed. It is toggled on and off with the View > Scale Bar command or by right clicking in the map window and selecting Scale Bar from the pop-up menu. Right clicking on the scale bar and selecting Properties from the pop-up menu, or double clicking on the scale bar, or selecting Edit > Scale Bar Properties on the Main Menu bar takes you to the Properties dialog, shown in the following illustration.

In the Type portion of the dialog, you select a block or ruler display style and specify scale bar ground units. The units of measurement affect the scale bar display only. The sample scale bar updates to reflect type and color selections but does not change to the selected units.

Background, the color behind the scale bar, and Text/Lines colors can be selected for both block- and ruler-type scale bars. When you select a block scale bar, the Major fill (fill color for the odd-numbered blocks) and Minor fill (color for the even-numbered blocks) can be selected or customized in the Color dialog.

You can let GeoMedia calculate your interval values, or you can specify settings for the number intervals and the length of the intervals between measurements on the scale bar. When you resize the map window, the scale bar automatically resizes. The scale bar length and the length of the intervals are shortened or lengthened according to the new map window scale.

The Text portion of the dialog allows you to set the font and font style for the scale bar. The "Save as defaults" checkbox indicates that the current settings on this dialog are to be used for all subsequent scale bars. The settings are stored in the GeoWorkspace. New workspaces use the default settings until the Scale Bar Properties dialog is changed.

North Arrow

The North arrow bar is a moveable object that shows the direction on a map to the geographic North Pole. It can be dragged to any location in the map window. The size of the North arrow does not change when a window is resized. However, if the azimuth is defined by the coordinate system, the North arrow is updated when the arrow is moved or when the map window is rescaled or panned. The North arrow cannot be updated if the azimuth is user defined. View > North Arrow toggles the display of the North arrow on or off in a map window.

The North arrow is not displayed by default. Its display is toggled on and off in the active map window through the View > North Arrow command or by right clicking in the map window and selecting North Arrow from the pop-up menu. A map window can contain only one North arrow. Its display characteristics can be customized with the North Arrow Properties dialog.

The size, background color, position, symbol used, and azimuth of the North arrow are changed in the Properties dialog. However, if you are running GeoMedia in Windows 95, you cannot change the arrow symbol or rotate the arrow in the map window.

The North Arrow Properties dialog, shown in the following illustration, is accessed by clicking on Edit > North Arrow Properties on the Main Menu bar, by clicking on the North arrow and selecting Properties from the pop-up menu, or by double clicking on the North arrow image in the map window.

The North arrow is a Windows Metafile (*.wmf). Several North arrows and compass roses are delivered with GeoMedia. They are stored in the <drive:>\Program Files\GeoMedia\Program directory. The current symbol field is read-only, and displays the name of the current North arrow file. If you are running Windows NT you can select another file for use as a North arrow if the arrow is stored in .wmf format. Browse to the directory containing the image, and select it from the listing. Select a size from the Size drop-down list. North arrows are defined in points, not in ground units.

Selecting a new color from the palette associated with the Background button changes the background color of the arrow. If you want the North arrow to appear transparent (that is, with no background color), set its background to the same background color in the map window.

The Azimuth of North portion of the dialog allows you to define your own azimuth, or to use the coordinate system of the GeoWorkspace to define the azimuth. To define your own azimuth of North, click on "User-defined type in degrees." The azimuth of North is measured clockwise from vertical. When degrees are set to 0, the arrow points straight up; 90 points the arrow horizontally to the right, 180 straight down, and 270 horizontally to the left. If you elect to define an azimuth, the North arrow will not be updated when the map view changes. When the azimuth is defined by the coordinate system, the display of the North arrow is updated when the view is changed.

The Preview box displays an example of the North arrow symbol, background color, and orientation you have defined. Preview cannot display arrows greater than 48 points.

Like scale bar properties, the settings on the North Arrow Properties dialog can be saved as the default settings for all map windows in the GeoWorkspace. If you do not check the "Save as defaults" box, only the properties and location of the North arrow in the active window are saved. If you want the North arrow to print without a background color, click on the "Print transparent" checkbox. In the following workflow exercise, you will work with scale bars and North arrows.

In this exercise you will learn how to add a scale bar and North arrow to your map window and customize their appearance. Open a new GeoWorkspace and create a connection to the parcels.mdb warehouse. Add the assessor_data feature class to the legend.

There are three tools for measuring features in the map window. The Measure Distance command allows you to see the distance between two points. It also carries a readout of accumulated distance between multiple points. The Select Set Properties dialog, discussed fully in Chapter 815, displays length or area of selected linear or polygon map features. Compound features with mixed geometry types cannot be measured. The Analyze Geometry command, discussed in Chapter 21, creates a query containing length, area, perimeter, and area/perimeter^2 statistics for a feature class.

Measure Distance calculations are dependent on parameters set in the Tools > Options dialog. Measurements can be calculated using either a projected measurement interpretation (which does not take the curvature of the earth into account) or a true method, which uses the earth’s curvature. The Units and Formats tab is used to specify the precision, units, and ground measurement method for distance and area calculations. The Map Display tab is used to specify the highlight color for selections, and the SmartLocate tab contains specifications for autopanning as you measure, Locate Zone size, and so on. The Options dialog is covered in Chapter 10.

Measuring Distance in the Map Window

To measure distance in the map window, click on Tools > Measure Distance on the Main Menu bar. The cursor becomes a crosshair. Click where you want to begin measuring. A dashed line is attached to the cursor. As you move the crosshair around the map window, the Distance and the Total fields in the Measure Distance display are continuously updating. When you left click again, the value in the Distance field is added to the Total field, the Distance field is zeroed out, and you remain in the Measure Distance program.

Each left click adds to the Total field. Right clicking in the map window resets both fields to zero. When measuring the distance between points, you can press the Backspace key to delete a previous point measurement. You can delete point measurements back to the initial point measurement. You can press the Escape key or double click on the window control icon of the Measure Distance dialog to exit the command.

Measuring Features in the Map Window

Measuring map window features is part of Select Set functionality, which is discussed in Chapter 815. It is presented only as a brief introduction here. To find the area of a polygon feature or the length of a linear feature, double click on a single area feature in the map window. The Select Set Properties dialog appears in the application window. The feature’s measurements are displayed on the General tab of the dialog.

Precision Coordinate Display

Another of the View tools is the Precision Coordinate Display, shown in the following illustration. It is a dockable window that provides you with several options for the display of coordinates in the map window. You can display coordinate readouts as projected x,y pairs or geographic latitude and longitude. You can also specify whether coordinates are to be constantly displayed as the mouse moves or updated only by a mouse click in the map window.

Like the measuring tools, Precision Coordinate Display is based on parameters set in the Tools > Options dialog on the Units and Formats tab. These parameters include coordinate order, units and precision, hemisphere designation, and projection quadrant.

Select View > Precision Coordinates to open this window. The window displays the precision coordinates for the current cursor position in a map window. Select the coordinate type Projected or Lat, Lon (Geographic) from the left drop-down list. Select the update options from the right menu. To turn coordinate display off, click on View > Precision Coordinates again, or click on the window control icon. In the following workflow exercise, you will explore precision coordinate display and measurement.

The Precision Coordinate window displays the coordinates of the cursor location. It is a window that toggles on and off. It can be docked in the application window above or below the map window. Coordinate readouts can be geographic or projected, and can be displayed dynamically as the cursor is moved around the map window or set to display only for a mouse click location.

Area or linear measurements, as a function of map object geometry type, are displayed on the General tab of the Select Set Properties dialog. Linear measurements can be made interactively by placing points in the map window. Distance measurements can either be point-to-point or cumulative. Measurements can be true or projected, depending on the coordinate system of the workspace and measurement defaults set in the Options dialog. Create a new GeoWorkspace and add a connection to the Louisiana.mdb warehouse. Add the Counties feature class to the legend.