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Frequently Asked Questions (FAQ)

Frequently Asked Questions about products by Thomas Hövel Software and information about known problems and work-arounds. Please choose one of these categories:

How to write your own Screen Savers

Technically speaking, a screen saver is simply an executable file (.EXE file) that is renamed to .SCR. Only few details are different about screen savers: Windows passes command-line parameters that tell the screen saver which function to run (configuration dialogue, full screen preview, thumb-nail preview in the Control Panel, password dialogue). Windows uses a special Windows message to test if a screen saver is running; screen savers should respond to this message.

Therefore you should be able to write screen savers with any programming language that is able to create .EXE files for Windows.

Detailed information including sources in C and C++ is included in the Platform SDK from Microsoft.

How to write screen saver modules for "2000 Lights Go Down"

Screen saver modues for "2000 Lights Go Down" are DLL files that export a few required API functions. API functions are called to initialize the module, to draw a single step, to configure and unload the module.

Sample source code is available for Delphi, Borland C++ (5.02) and Watcom C++ (10.6). You should be able to use any other programming language that creates DLLs for Windows.

The advantages of creating a screen saver module for "2000 Lights Go Down" instead of a .SCR file are obvious: Modules can run in the Randomizer so there is variation through interesting new combinations!

What do you need to create screen saver modules?

Sample source code and API documentation is included with the free Standard Version as well as with the Try-Before-You-Buy-Version (Shareware Version, free 30 days evaluation).

You can freely distribute your own screen saver modules without paying any royalties. You can pass the free Standard Version along with your modules provided the original distribution file(s) are not changed and the licence agreement is not violated.

2000 Lights Go Down (95 Lights Go Down)

Known Problems

Screen saver module Bobby: procection fault in ATI*.DRV running under Windows 98: This is a bug in the ATI display driver (so far this bug occurred only under Windows 98; Windows NT and Windows 2000 do not have this problem). To correct this problem, open "Start" and "Settings", select "Control Panel", open "Display", go to the "Settings" tab and select "Advanced...". On the "Performance" tab, adjust the "Hardware acceleration" option to either "No accelerator functions" or "Basic accelerator functions".

Applies to: 2000 Lights Go Down Version 1.00 (corrected with Version 1.01 released June 30, 2000): During Uninstallation, sometimes the error message "Internal error, unable to load or call external DLL. Please contact your vendor for more information." is displayed. This problem occurs under Windows NT 4.0; it also occures under Windows 2000 if the program path matches the 8.3 convention. Solution: download PATCH2KE.EXE (only 9 kB) (ftp://ftp.th-soft.com/patch2ke.exe) and execute it; Uninstallation should then proceed without problems. (To find your screen saver version, open the Readme! file (a shortcut is in the program group)).

WinCIG (Chaos-Bilder-Generator, Chaos Image Generator)

Where does it save co-ordinates? Co-ordinates are saved in the configuration file WINCIG.INI which can be found in the same directory where the program is. This is a text file, so you can read the settings; be very careful if you edit this file!

WinCIG does not save co-ordinates! WinCIG cannot save co-ordinates if the file WINCIG.INI is read-only or in use by a different application. Please note that files are read-only when copied from a CD-ROM! Versions up to 1.03 didn't display an error message when saving failed. Versions 1.10 and higher display an error messages when saving fails.

How many colours does WinCIG use? WinCIG uses up to 256 colours. Windows reserves 20 colours for its own use, therefore only 236 colours are available for WinCIG when the display is configured for 256 colours. This is the reason why we recommend a display mode with at least 32k colours to avoid any loss of quality.

WinCIG up to version 1.2: Error if available memory  >= 2 GB This bug occurs in the Display Options dialog and is fixed with version 2.0. {The problem was actually caused by a bug of the Delphi 3 compiler; current versions use the Delphi 5 compiler.}

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