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- This is the description of the screensaver modules
- 4colprob.ssm, bounce.ssm, numlock.ssm and space.ssm.
-
- I release these modules as FreeWare and without any warranty
- of any kind and so on. Please read the note below concerning
- the module numlock.ssm (Numlock Blinker), and please don't tell me
- that I haven't warned you!
-
- If anybody is interested in the sources, please feel free to
- contact me.
-
- Any comments, suggestions or bug reports are welcome. You can
- contact me as follows:
-
- eMail (InterNet): Nicole.Greiber@Fernuni-Hagen.de
-
- or Snail Mail:
-
- Nicole Greiber
- Brueningstr. 6
- 42119 Wuppertal
- Germany
-
- Below you find a short description of the modules. Please read at least
- the first one (Numlock Blinker) because it's a bit tricky to handle.
-
-
- numlock.ssm (Numlock Blinker):
- When this module is active, you will not see anything on the screen -
- but watch your keyboard!
-
- CAUTION:
- You should not stop this module by pressing Num Lock, Scroll
- Lock or Shift because then the key may change its mode. This is not
- my fault because when the module is started, it saves the state of
- the lamps, and before it exits it restores this state. But when the
- state of a key is changed in between, the module will still restore
- the lamp's state as it was at start time because the main ssaver
- program only notifies the module that a key was pressed but not
- which one.
- If you already ran into trouble due to this problem, you can do the
- following:
- If you have problems with the Caps lock key, just toggle it one or two
- times. It will then work fine.
- If one of the two other keys causes a problem, just run the module
- and stop it with that key once again. The procedure will
- be reverted and everything's fine again.
- (This worked at least in my case. If it doesn't help you,
- re-IPL and pray :-) )
-
-
- 4colprob.ssm (4 Colour-Problem):
- This module was inspired by the article "Dreiecksgeschichten"
- by Dr.-Ing. Reinhard Ludwig, which was published in the german
- computer magazine "c't", April 1994, pp. 220. The article included a
- Pascal program. I translated it to C and modified it slightly.
-
- This module represents a well-known mathematical problem: to colour
- a given map with 4 colours so that two neighbouring fields always
- have different colours.
- For this problem a map is needed, therefore several steps are necessary:
-
- First, a number of random points is created (the number can be varied
- between 5 and 75 in the "Module Configuration" window). Then the
- screen is triangulated, that means the given points are used to
- create triangles (this is called Delaunay-Triangulation).
-
- After that the screen is divided into sections, of which every
- section encloses one of the random points and every pel on the screen
- that is closer to the random point than to any of the other random points
- (this is called a Voronj-diagram). This diagram represents the map to be
- coloured.
-
- You will notice that there may be five colours: red, blue, green,
- yellow and light blue. The light blue fields are "wrongly-coloured"
- fields, and after all fields have been coloured, the light blue
- fields will be eliminated one after the other by swapping colours with
- one of their neighbouring fields and thus finding a field where only three
- colours are represented in the neighbouring fields. Then this field
- can get the fourth colour, and the light blue colour is no longer
- needed. When all "wrong" fields have changed their colours, the process
- is terminated and you can see a map that is coloured according to the
- 4 colour-problem.
- Sometimes the light blue can't be eliminated at the first attempt.
- Then the whole map is coloured anew, and the program tries again.
-
- bounce.ssm (Bouncing Line):
- Here you see a bouncing line that changes its colours. You can select
- how many lines will be visible and how many lines will be coloured in
- the same colour. On startup, the screen can be painted black or left
- as it is.
-
- space.ssm (Space Flight):
- You will fly through space, the final frontier! Choose speed and
- star density as you like. When this module is run with
- "Low Priority" unchecked, the animation will be smoother.
-
-
- Enjoy!
-
- Nicole Greiber
-
-