KSEG runs on Windows and Unix-based platforms (according to users, it also compiles and runs on Mac OS X and should run on anything that Qt supports).

You create a construction, such as a triangle with a circumcenter, and then, as you drag verteces of the triangle, you can see the circumcenter moving in real time.

Of course, you can do a lot more than that--see the feature list below.
KSEG can be used in the classroom, for personal exploration of geometry, or for making high-quality figures for LaTeX.

KSEG is very stable, fast, and the UI has been designed for consistency and efficiency.

Here are some key features of "KSEG":

· Fast core which can support large constructions
· Free/GPL-runs on Linux (and probably most other systems which support Qt)
· Supports multiple languages
· Fully Documented
· Construction of points, segments, rays, lines, circles, and arcs
· Make measurements
· Transformations (rotation, translation, scaling, reflection)
· Construction of adaptively sampled loci for better quality and speed
· Reverse dragging
· Infinite undo/redo
· Ability to easily redefine points to "edit" drawings
· Easy to use editable scripting/macro with support for recursion
· Pretty formulas for calculations-with my libkformula
· Pretty colors, fonts, etc.
· View panning/zooming and multiple simultaneous views
· Export view to image file, including antialiased option
· Printing
· Selection Groups--group a bunch of objects, then select them later with two clicks

What's New in This Release: [ read full changelog ]

· Fixed compilation bug
· Printing now produces good postscript