PlanetGIS User Guide/Working with Views
From PlanetWiki
Contents |
Working with Views
Introduction
A view in a PlanetGIS map is a collection of displays intended to illustrate a particular aspect of a map. Often separate views contain separate themes (in the broader sense than defined below) or different types of data is placed in different views so as not to clutter the map. (Example: a contour map and a cadastral map of the same area).
Views are also used to conveniently access maps of different sub-areas in a project area. A municipality may consist of a number of disjoint towns and villages and a view can be set up for each so that only the intended area is visible in each view.
Another use for views is to set up different configurations of print formats. You might have a view for an A0 plotter and another for A4. These views would have different print frames preselected for them.
As with most types of objects in PlanetGIS, you can create a hierarchy of views and sub-views. A view for Village A, for example, may have different sub-views showing the electricity network and the water network.
Creating Views
View Properties
Several settings may be set for each view of a map. The properties window is accessible by right-clicking on a view tab or on the view's node in design mode. The settings are divided into the following four sections.
General
- Changing the name of the view
- Setting the background colour
- Whether or not to include the displays of parent views when drawing the map
- Smart draw ordering
- Automatic refreshing
In addition, you can click on the Frames button to select print frames for the view.
Smart draw ordering is on by default for views and when enabled will change the order in which the feature classes of displays are rendered as follows: regardless of the order in which displays appear in the display manager, PlanetGIS will:
- Draw all raster images first, in order that they are listed;
- Draw all fills for areas second, in the order provided;
- Draw all lines and outlines for lines and areas third;
- Draw all symbols fourth;
- Draw text and labels last.
Note: starting with version 3.0.5, the order in which fills and lines are rendered can be influenced in the style properties by assigning non-zero priorities to them.
Automatic refreshing is a feature introduced in version 3.0.2 for applications where constantly changing features are being monitored. An example is when a fleet of vehicles are being tracked and their positions updated at regular intervals. With automatic refreshing the map will be automatically redrawn if it hasn't been explicitly redrawn through user interaction during the specified period.
Activate/Limit
You have the option to use a feature, in which case you need to specify its key. The optional scale allows you to centre the feature on screen at the specified scale.
The second option is to use a saved location for the activation/limit. (See Saved locations).
Tab Image
A small icon may be selected to display in the view's tab. Use this page to select or clear such tab. For Windows bitmaps (which cannot specify transparency) you have the option to specify which colour should be used for a transparency mask by setting the bottom-leftmost pixel in the bitmap to that colour.
Grid
Select Fixed interval if you have a specific preference, otherwise Planet will decide on an interval based on keeping the grid lines at a reasonable distance from each other.
You also have the option to show “ticks” (short lines around the border of the map) instead of lines traversing the map, as well as whether or not to display the coordinate values of each grid line.
Finally, you may choose your own style for the display of the grid lines and coordinate text.
| Previous: Using Styles | Next: Design Mode |
