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Testing the world-rasters.sqlite sample database

This quick tutorial explains, by practical step by step examples, how to use the Map Panel tool.
The goal is to familiarize yourself with the new Map Panel feature, by repeating each single step shown.

You need to download the world-rasters.sqlite sample database.
Then you must start spatialite_gui 2.1.0, connecting to this database.

Step #1: displaying the Raster Coverages

First, open the Map Panel.
The Map Panel will be initially empty. Now you must select ae Raster Coverage to be displayed on the Map Panel.
Select 'blue-marble' from the list and confirm.
Now the 'blue-marble Coverage will be displayed at its full extent. Use the classic Zoom-In tool (Left-Click and Drag) in order to select a portion of the Map. (Left click will Zoom In one Level)
The classic Pan tool is supported as well.
And there is also the classic Zoom-out tool (Left click will Zoom Out one Level). Exercise play with the Zoom-In, Zoom-Out and Pan tools so to familirize yourself with their behaviour.
Next, add both the 'city-lights' and 'etopo1' Coverages to the currnt Map. Hide the other coverages until only 'city_lights' can be seen.

Step #2: handling multiple alternative Styles

Both the 'blue-marble' and 'city-lights' are simple RGB rasters, supporting the basic default Style.

Now hide 'city_lights' and show the 'etop1' coverage, which is more interesting since it supports multiple, alternative, Styles.

Use the Configure tool to swiftly switch from one Style to another.

Just select the new Style from the list and then press the Apply changes button.

As you can see the new Style will be immediately applied to the current Map.

Recapitulation

a Raster Coverage may (or may not) be supported by one or more Style(s).
if no Style is associated to a Raster Coverage then a default Style will be automatically applied.
Note: default styles can be used for grayscale or RGB rasters, but are surely unfit for data grid and multi-band rasters.
if just a single Style is available it will be automatically selected.
if multiple Styles are available the first one will be automatically selected, but you can easily switch to another Style in the most dynamic way.

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