3D graphs

A program for displaying the 3D-graph of user-defined function of two variables.
You can enter a function as a string, the expression solver is also included. You may also define ranges of variables x,y. Then the program displays the 3D-graph, which may be rotated, zoomed, etc. It works in several graphic resolutions, the expression may be saved to disc.
I've written this program as a task of a correspondent-stage of ICP'97 (International Competition in Programming) - its final was held in Brno, Czech Republic on the INVEX'97 computer fair and I placed 7th.
This program is partly translated to English : use /english switch.
Technologies used: