These tips result from years of experience and may prove useful even for advanced users.

1. Select the current object

Users can select the current object, the object that is moved, rotated, scaled, and exported to a file. The current object can be a single object or a list of objects. First click the mouse middle button over an object name, on the top menu. Then click over an object of that class, to select it, or over the Gamgi button, to select the current list of those objects.

2. Select the current layer

Users can select the current layer, the layer where are the objects that can be directly manipulated. Press the mouse middle button over Layer, on the top menu, then click over the graphic area, to select the layer from a pop menu. The new current layer becomes automatically the current object. Layers can be transparent or opaque. Objects in different layers can be manipulated simultaneously using lists of objects.

3. Use lists of objects

Handling lists of objects are a powerful technique to manipulate simultaneosuly arbitrary sets of objects previously selected. Using Object->Select dialogs, objects can be added or removed, picked one by one, selected by region or by a wide range of properties.

4. Use lights

Solid objects require lights to look good. Just press Light->Create and then Ok to create a light. If lights are interfering with wired objects, use two transparent layers, one with solid objects and lights, the other with wired objects and no lights.

5. Move objects away

Large objects in Ortographic projection tend to be too close to the viewer, resulting in broken lines and surfaces. The easiest solution is to move the objects away, along the z direction. Just press Move to activate the ruler, and press the left (negative) half of the ruler with the third (z axis) button, until the image looks correct.

6. Customize the ruler

In Window->Config, the ruler can be configured to arbitrarily high levels of accuracy. For example, setting Rotate Max and Step to 0.5 and 0.1 respectively, will configure the ruler in Rotate mode, from -0.5 to +0.5 degrees, in steps of 0.1 each.

7. Import multiple files

GAMGI can load an arbitrary number of files, local or remote, with a single shell command. Try for example:

gamgi http://www.gamgi.org/dat/molecule/silicates/q10.xml ftp://ftp.gamgi.org/gamgi/dat/molecule/silicates/q10.xml

8. Set user preferences

Importing automatically a file with default data everytime GAMGI is launched is a flexible and powerful way to set preferences. For example, adding this line to ~/.bashrc:

alias gamgi='gamgi ~/gamgi/defaults.xml'

will import the file defaults.xml everytime gamgi starts. To turn C atoms grey by default, add this data to defaults.xml:

<gml>
<gamgi>
<atom element="C" red="0.5" green="0.5" blue="0.5"/>
</gamgi>
</gml>