Ondrej Psencik, 1999

Info about Applet PapsekVOkoliCocky:

classes:
========
PaprsekVOkoliCocky extends Applet 
  - main class
Epanel extends Panel 
  - respond on various Mouse actions
CentralniTeleso extends Panel 
  - this class sumaries properties of gravitational mass
ZdrojPaprsku extends Panel
  - this class summaries properties of source of light


Running Applet:
===============
Apllet is started from appropriate html page start.html.
After a while applet is running, we can see central mass, 
two sources of light and appropriate vectors. 
In this moment it is possible several ways of controlling 
simulation. Pressing button START cause release of lighy 
from sources and incurvation of beams. Other way is that 
we can dragging central mass and see instantly (depends on
power of computer) simulation, another nice way is moving 
with scrollbar (changing weight of mass) and seeing fast
colorful simulation.

Direction of beams we can change by dragging & moving.
We can drag & move sources of light (appropriate cursors 
are assigned) or vectors (various colors). Dragging end 
of vector (blue rectangle is appeared) change direction,
dragging body of vector change position of source.


Troubles:
=========

In this Applet we found various bugs, but after a consultation
with Doc. Bloch & Doc. Kulhanek, more of them was killed.
But some of them are presented in this version:

-on slow machine(computer) error is generated in some paint methods 
 in Canvas classes, courses are not repainted correctly and 
 on drawing surface we can see garbage

-sometimes Mouse events are handled very funny, other object is
 responding on this event



