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Creating the world-rasters.sqlite sample database

This quick tutorial explains by practiacal step by step examples how the world-rasters.sqlite sample database was actually created.
It's mainly intended for didactic purposes: you are expected to replicate all single steps, and at the end of the process you'll surely master the new tools and wizards supported by spatialite_gui 2.1.0.

Raster Coverages list:

ETOPO1: a well known Global Relief Model.
NASA Blue Marble: the most detailed true-color image of the entire Earth to date.
NASA Earth's City Lights: how Earth appears during the night.

Step #1: setting up the ETOPO1 Raster Coverage

First of all you have to create a new Raster Coverage

Fill all required dialog fields and finally confirm.

A nessage box will pop up so to confirm that a new (empty) Raster Coverage has just been created.

Now you are ready to populate the Raster Coverage by importing the corresponding GeoTIFF file.

Hint

if your CPU has multiple cores you could usefully enable RasterLite2 to execute more parallel threads in order to significantly speed up the import process.

SELECT RL2_SetMaxThreads(12);

Just select the GeoTIFF file path, then confirm.

A message box will pop up so to confirm that the Raster Coverage has been succesfully populated.

Now you have to compute the total Extent (BBOX) of the Raster Coverage.

Warning

all Raster Coverages missing a valid Extent declaration will always be silently ignored and will never be published.

You are warmly encouraged to always set the Copyright and License informations for all your Coverages.

Just fill the required dialog fields, then confirm.

ETOPO1 actually is a numeric data grid, so it surely requires some appropriate styling rules.
The first step is importing such styling rules into the database from their corresponging XML (SLD/SE) files.

Select all the XML file paths (you can import more files at the same time), then confirm.

A message box will pop up so to confirm that all Styles have been succesfully imported.

Final steps: now you have to create an association between the Raster Coverage and its supported Styles.

Press the Add Style(s) button.

Select from the list all Styles you intend to associate with the current Coverage, then confirm.

You could eventually remove some Style by pressing a mouse right-click on the corresponding row; otherwise you can just quit the dialog box.

All right; the ETOPO1 Raster Coverage is now ready to be published !

Step #2: setting up the BLUE MARBLE Raster Coverage

This step is strictly similar to the previous one.
The most striking difference is in that BLUE MARBLE is an RGB datasource, so no special Styling rules are required, and this implies a strong simplification.

We'll examine in full detail just the more relevant differences.

Creating the Raster Coverage.

Exercise: discover by yourself where and why different settings have been applied int this case.

Populating the Raster Coverage.

Caveat: BLUE MARBLE is distributed in the form of plain TIFF files lacking any georeferencing.
You are requested to manually create by your own the appropriate .tfw WorldFiles (a rather trivial task).
The side figure shows the settings required to import TIFF+TFW files.

Don't forget to preoperly set the Copyright and License information.

Final step: always remember to compute the Coverage Extent

All right; the BLUE MARBLE Raster Coverage is now ready to be published !

Step #3: setting up the CITY LIGHTS Raster Coverage

This step is practially the same of the previous one

We'll examine in full detail just the more relevant differences.

Creating the Raster Coverage.

Setting the Copyright and License informations.

Final step: always remember to compute the Coverage Extent

All right; the CITY LIGHTS Raster Coverage is now ready to be published !

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