Example:
The construction of two points and the segment joining them.
Initially, the user must activate the
action related to the point creation
(
Create point in the drawing area or on object) by clicking on the button
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.
After this, the user must "click" on the drawing are twice, on the position that each point must be created
(we will be supposed labeled by
A and
B).
The next step is to "click" on the primary button for straight lines
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, which activate
the secondary button responsible for lines.
If the secondary button for segments
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isn't activated, "click" on it.
Now "click" the point
A, release the "mouse" button, move it to the point
B (during this movement
it will be shown temporary segments), when the point
B becomes yellow (otherwise a NEW point will be created,
producing a segment that is independent of
B), give another "click". There it is, the segment
AB is created,
this menas that: whenever point
A or
B is moved, the segment is automatically updated by
iGeom,
preserving the relation between the segment and both given points.
This is the most important feature of any Interactive Geometry software: the movement of points and the automatic
update of other related objects, preserving existent properties between them.