Objects and (TODO) lists of objects can be selected using just the mouse and simple 
graphic techniques, described here. For more complex selections, involving combinations
of graphic and algorithmic techniques (TODO), for each object class, please consult 
the corresponding 
Object Select section.
When rotating,moving,scaling (and 
Axes is off), only the currently 
selected object changes. When exporting to a file, only the currently 
selected object is exported. Learning how to select objects in GAMGI is 
thus crucial for users.
Single
To select an object, press the mouse middle button over the window main menu, on 
the corresponding object class. This tells GAMGI which class of object the user is 
about to select. Then press the mouse (any button) over the visual representation 
of the object. If the selection succeeds, a beep is emitted and the object 
identification is shown in the window status bar. If GAMGI finds no object, 
or more than one, in the sampled area, the mouse action is ignored. If two objects 
are one over the other, GAMGI chooses the object that is closer to the user. 
How to change the size of the sampled area, around the clicked spot, is described 
in 
Gamgi Config. 
The visual representation of an object is defined in GAMGI by the object itself 
and by the objects that it contains. If an atom owns a text, the text is part of the 
atom visual representation, even if the text is very far from the atom. When selecting 
the atom with the mouse, it has exactly the same effect to click over the atom or over 
the text. Bonds are a special case, because they have two parents (the atoms), instead 
of a single one. In this case, each half bond contributes to the visual representation 
of the nearest atom. A bonded atom can be selected clicking over the atom or over its 
nearest half bonds. A bond can be selected clicking anywhere over the whole bond, 
including the objects it contains.
Objects that have no visual representation in the drawing area, lights, layers and windows, 
are selected as follows: after selecting the object class with the middle button, press the
mouse anywhere over the drawing area: a menu pops up showing the identification of the 
various objects available for that class. If one is selected, a beep is emitted and the 
object identification is shown in the status area below.  
Text, 
Group, 
Cluster and 
Assembly are recursive objects, 
in the sense that they can own or be owned by other objects of the same class. Therefore 
a combination of the two selection techniques described above is often required to 
distinguish these objects. If a group contains a group, which in turn contains an atom, 
clicking on the 
Group menu and then over the atom is ambigous: which group is 
the user trying to select? everytime this ambiguity occurs, a menu pops up showing the 
identification for the various candidate objects. If an option is selected, a beep 
is emitted and the object identification is shown in the status area below.
Clicking twice over the 
Layer, 
Window, or 
Gamgi menu, a beep is 
emitted and the selected object becomes the current layer, the current window or 
the current gamgi (everything), respectively. This short-cut is convenient to easily 
select the current layer and to export to a XML file everything in the current layer, 
in the current window or in the whole gamgi process.
If users position the mouse pointer over the File or Help menus and then press 
the middle button, nothing happens.
Multiple
To select a list of objects directly (TODO), without calling any 
Object Select 
dialog, first tell GAMGI the class of the objects that are going to be selected.