Copyright © 2001 Marc Bartsch
Permission is granted to copy, distribute and/or modify this document under the terms of the GNU Free Documentation License, Version 1.1 or any later version published by the Free Software Foundation; with no Invariant Sections, with no Front-Cover Texts, and with no Back-Cover Texts. A copy of the license is included in the section entitled "GNU Free Documentation License".
KGeo is a program for interactive Geometry
Table of Contents
KGeo is a program for interactive geometry just like programs such as Euklid, Zirkel und Lineal or Kseg. It was my intention to write an open source version of this software that is free for schools and combines the best of both (all) worlds.
This manual describes KGeo Version 1.0.1. Further to giving a general introduction how to use KGeo I also want to point out possible applications in the Math classroom. Whoever wants to add some applications of KGeo is very welcome: <marc.bartsch@web.de>.
KGeo supports three different operation modes. First of all there is the construction mode used to set up points, lines, circles and the like. Then there is the drag mode which allows you to drag around constructed objects, showing the immediate effect of this movement. For example let's think of the circle of Thales. If you move the point opposed to the hypotenuse of the triangle along the circumference of the enclosing circle, you will see that the angle remains a constant 90 degrees. The third mode is the trace mode. You can mark points, so that they leave a trace when they move, i.e. they leave a trace where ever they moved over and you can see the way an object went. Next I'll describe each of those modes in a more detailed way.
On the left side of the main view (canvas) you find all the tools needed to draw geometrical objects. The first button, for example, shows a point and that is exactly what is drawn on the canvas if you select this tool by clicking on the button and then clicking somewhere on the main view.
All the tools are organized in groups to help you to find the tool you are looking for. If you choose the segment tool, for example, you can click on two different coordinates of the main view and a line segment will be drawn between those two points. If you choose the segment tool a second time, you can also click on existing points and thus construct segments between points you have created earlier.
If you are not sure what a tool is doing just move the mouse cursor over the button and wait for a second. The tool tip will tell you exactly what you can do with it.
The drag mode is very useful to demonstrate, how geometrical objects are related to each other. Right now only points can be dragged around. After every construction KGeo switches from construction mode back to the drag mode. Due to that you have to select a tool again to continue constructing some figure.
Points can have a trace mode which means they leave a trace over every
place they move. You can apply the trace mode with the following tool
. After that you can
click on the point that should leave a trace. You can turn off the
trace mode by applying the trace mode tool a second time.
This is an example of a point leaving a trace.
Construct a point.
Construct a point at (x;y).
Construct a point on a line or on a circle. This means that the point is attached to those objects.
Construct the point of concurrency of two lines, segments, rays and so on. Since you cannot drag around a point
of concurrency, it is drawn as a little square.
Construct the bisection between two points.
Construct a mirror point. You can either mirror
the point at another point or at a line. The first point you click on
is the one that will be mirrored. Then you can click the line or the
second point.
Rotate a point around another point. The angle will taken from a already constucted angle. The first point you click on
is the one that will be rotated and and the second point is the center of the rotation.
Move a point. Click on a point that you want to move and then on a vector that defines the movement.
Construct a segment between two points. The points do not need to exist, they will be constructed, as soon as
you click on an empty spot.
Construct a segment. You also need to points for that.
Construct a triangle. You need three points for that.
Construct a vector. A vector is segment with a direction. You need a vector to move a point.
Construct a ray.
Constrcut a parallel line. You need to click on an existing line and then choose a point through which
the parallel line should run.
Constrcut a perpendicular line. You need to click on an existing line and then choose a point through which
the perpendicular line should run.
Construct a circle. The first point is the center and the second point defines the diameter.
Construct a circle with a fixed diamter which will be entered through a dialog.
Construct an angle. You need three points for that where the second point is the center of that angle.
This chapter shows you how you can use KGeo for your lessons.
Please, do the following:
Procedure 3.1.
Construct three points at (-2;0), (0;0) and (2;0) respectively.
Construct a circle around the point in the middle with the radius 2. The two other points are now located at the circumference of the circle.
Construct a point on the upper half of this circle.
Draw a triangle through this point an the ones on the left and the right on the circumference of the circle.
Measure the top angle.
If you move the point on the upper half of the circle, the angle will remain 90 deg.
Creates a new construction
Opens a construction
Lists the last 5 files
Closes current construction
Saves the construction
Saves the construction under a different name
Prints the current construction
Exit KGeo
Opens dialog to change preferences
Switches to full screen mode
Invokes the KDE Help system starting at the KGeo help pages. (this document).
Changes the mouse cursor to a combination arrow and question mark. Clicking on items within KGeo will open a help window (if one exists for the particular item) explaining the item's function.
Opens the Bug report dialog where you can report a bug or request a “wishlist” feature.
This will display version and author information.
This displays the KDE version and other basic information.
KGeo 1.0.1
Programm Copyright 2000-2001 Marc Bartsch <marc.bartsch@web.de>
The KGeo Icon is a variation of the Kontour icon (KOffice).
Dokumentation Copyright 2001 Marc Bartsch <marc.bartsch@web.de>
This documentation is licensed under the terms of the GNU Free Documentation License.
This program is licensed under the terms of the GNU General Public License.
KGeo be downloaded for free under http://kgeo.sourceforge.net
To use KGeo, you need KDE 3.X and Qt™ 3.X.
You can find KDE at http://www.kde.org/, Qt™ at www.trolltech.com.
In order to compile and install KGeo on your system, type the following in the base directory of the KGeo distribution:
% ./configure % make % make install
Since KGeo uses autoconf and automake you should have no trouble compiling it. Should you run into problems please report them to the KDE mailing lists.
You can also reach the author directly at <marc.bartsch@web.de>
If you want to delete KGeo from your system, please type:
% su % Password: % make uninstall