In the previous posts of the symbols series, we have seen how to create a symbols library form a set of images, realising some examples such as Google and OSM libraries.

It can be interesting as well to realize our own symbols library from different external sources. They can be made of letters, numbers or special characters as symbols or even graphic symbols.

As an example, we are going to use one source containing animal symbols.

After having downloaded it and installed in our system, we will transform it into images by using Inkscape, an open source software for vector editing that we have already mentioned in other posts.

To install a source it is only needed to open it with the typographic viewer of our operating system  and click on Install.

Once installed it will be shown as part of the available fonts in Inkscape. Add text and, for example, if we write “ABCDEFGHI”, something like this will appear:

We will transform these characters into single images in two simple steps:

• Path/Object to Path: transform the character into image.
• Object/Ungroup: create a single image for each character.

Then we have just to select each of them and save one by one as single file by “File/New”, assigning to any single document a size similar to the image ones. Cut and paste the image into this new document (for example the first, the caiman) and by “Object/Align and distribute” align it in the centre. Save it with a name easy to be identified (Caiman.svg). Done.

To have a different symbol when selected, fill the image with yellow colour and “Save as” with the same name but adding at the end “_sel”.

This action can be repeated to as many symbols we want to load. From now on, we only need to use the gvSIG symbol loader in order to have our new symbols library available in gvSIG.