0rfelyus's homepage
My foto 22 years ago

My photo from times when I was young, beautiful, promising and clever.

Today, I am just clever.

[Past projects] [Current projects] [Planned projects]
[News] [Texts] [Friends] [Links #1] [Links #2]

This page is devoted to presentation of (hopefully small) fragment of myself. Daniel Skarda - that is my name, but when I have to deal with computers I use nickname 0rfelyus. It does not mean I am a childish "wannabe" who wants to have a cool name. Let's just accept the fact that on Internet nobody knows you are a dog, so it really does not really matter for you if you know me as 0rfelyus or Daniel Skarda.

Since you came here through Internet I expect that you are more interested in informations about/from 0rfelyus rather than about Daniel Skarda. Before we definitely stop talking about Daniel, we should at least write his (real world) address.

Daniel Skarda
Vesinova 16
100 00 Prague 10
Czech Republic

phone: +420 - 2 - 74 77 33 19
e-mail: 0rfelyus@ucw.cz
ICQ: 127364399


Aug 21 2001 Added ICQ number + few minor changes
(it is time to major update of my homepage)
Dec 1 1999 I have new telephone number 74 77 33 19.
Oct 12 1999 Added link to new project - guileGL
Sep 27 1999 Added link to my Flex & Bison tutorial (in czech)
Apr 15 1999 I finally found some time (umm, where?) and reworked my outdated homepage. Hope you will like it.

Links #1

As I was writing this page I found that to newcomers some terms could seem strange and unknown (free software, open source, GNU, GPL,...) Because these terms were explained thousand times by thousands people I doubt I can do better then them - so I decided to divide Links section and before presentation of my "projects" refer to pages where you can get some clue about these issues.


Richard M. Stallman, The Free Software Foundation and GNU (Gnu's Not Unix) project.


Page about open-source software, its definition,...


Eric S. Raymond's Home Page. Eric presents another view on free (open source) software with different motivation, premises and goals. Even though I am closer to Stallman's point of view, I think that Eric essays are worth reading. If you have not read his famous "Cathedral and Bazaar" you definitely should.


Czech pages about GNU, Linux, Czech Free Software Foundation, Linux...


My bookmark list. Huge, mostly unsorted and unmanageable beast - as any other list of bookmarks is.

Current projects


Gag is plug-in for The GiMP (GNU Image Manipulation Program). In Gag you can search space of procedural textures using genetic algorithms (simply - with Gag you can generate interesting and original pictures).

Still in development.
Latest version is 0.5


Pie menus are less known alternative to menus as you know them from most nowadays applications. Although for first sight they could seem very strange and unusual, in fact you can control your programs with them much faster than with common menus. So do not miss GtkPieMenu homepage

Beta version 0.1


guileGL allows to access OpenGL library from Guile (GNU Ubiquitous Intelligent Language Extension) - so you can play with 3D graphics from interpreted scheme language.

Beta version 0.1.0

KiWi Awk

Kwa is my implementation of Awk language. Nowadays it implements almost whole language specification (and GNU extensions). Even though I know Perl language quite well I am not comfortable with its syntax with too many features but (IMHO) no glue. So I started Kwa which extends Awk in places, where (from my point of view) Awk lacked some features or where I found Awk too awkward.

Not yet finished / released.


As two characters 3D in project name can suggest this project aims to be system for modelling/animation. After many months of development we (we = Trapas Team) have quite cute kernel, rendering (OpenGL), scripting language (Guile), constrain solver,... but Trapas still lacks some key features (modelling, animation, texture editor - to name uninteresting ones).

Not yet released
(Still building cathedrals)


Till I started my fight with XKB (X Keyboard Extension) I was not happy with any X keyboard with Czech layout. Ucw-cs/X is result of that battle - it combines layout of Czech keyboard for Linux console by mj with other types of Czech keyboard. I can not say that this is universal solution for everybody - it just perfectly fits my needs.

Beta version 0.1

Previous projects


0GE is graphics editor I wrote about about 5-8 years ago. In that time I studied on high school, MS DOS was my only experience, Borland Pascal my only IDE. Ummm... - sad times. Even though 0GE abilities are limited by "well designed" MS DOS features, OGE has some interesting functions which can not be found in comparable editors.
Sources: .rar, .arj, .tar.gz.
Dos binaries: .rar, .arj, .tar.gz.

Latest release:
about four years ago.

Breath-taking news:
GPLed source code.


0rfVizn was OO GUI toolkit for DJGPP and GRX library. It was one of the only two positive results I did while my strange experience with commercial sphere (the second positive result: I got some money and bought my first computer).
I intended to release 0rfVizn under GNU GPL but later I installed Linux (and X Windows) and found that there are better (and standard) ways how to program GUI (Motif, later Gtk+ and Qt).

No release.


ParImp was the first of series of patches I wrote for Persistence of Vision Ray tracer (POV-Ray). This patch extends POV-Ray 2.2 with ability of ray tracing implicit and parametric surfaces using interval arithmetic.
I wrote this patch with my friend Tomby as a part of Computer Graphics course. Later it became part of IsoSurface patch by Ryoichi Suzuki and part of SuperPatch. Hopefully sometime it became part of official POV-Ray distribution.

Version: 0.92
(about two years ago)


POV-Ray with Macros patch was result of my plays with POV-Ray parser. Current implementation of macros in POV-Ray is inspired by my patch. Just inspired, that is all.

Released and forgotten.


This patch is the last in my series of patches for POV-Ray. It extends POV-Ray by ray tracing of trimmed rational Bezier surface patches using Bezier clipping (as described by Nishita, Sederberg and Kakimoto).
The main gain of this algorithm (beside trimming and rational surfaces) is in its speed and memory requirements. Ray tracing using Bezier clipping is as fast as POV-Ray's original algorithm but it does not need any memory for precomputed data.
Also became part of Superpatch.



Motion blur

These are two plug-ins I wrote for The Gimp. I am not original author - I just rewrote (with few enhancements) these plugins from old Gimp 0.54 API to new Gimp 1.0 API. Now up to date version of these plug-ins are part of official Gimp distribution.
Original authors were Thorsten Martinsen and Federico Mena Quintero.



(summer 1996)

Linux, free software and Linux application is main theme of one seminar on our faculty. About three years ago I had small lecture about MuPAD and its abilities.

[in Czech]

Config tools
(summer 1998)

Same seminar but different theme - autoconf, automake and libtools.

[in Czech]

Bison and flex
(winter 98)

Yet another Linux seminar tutorial - this one about Flex and Bison.

[in Czech]

(summer 99)

[in Czech]
Not yet finished.

Planned projects

(with Tomby)

The main purpose of Humbuk (also known as 3pm) would be replace mp3 with completely free format (not restricted by various ugly patents).

Neat idea. Just looking for some time (and courage) to start Humbuk.

Pie menus for Window Maker

Yet another step in my pie mania. I would like to try implement pie menus for my favourite window manager - Window Maker.

Planned, not yet started.


Finally I would like to find some time and sort my bookmarks...

Just a dream :)


[Tomby] [TuhMen]
(0rfelyus+Tomby+Tuhmen = Tuh0r Team)

[mj] [Pavel] [Milan] [Vojta] [Vitas]

Links #2





Linux Weekly News


My bookmark list. Huge, mostly unsorted and unmanageable beast - as any other list of bookmarks is.


Emacs - my favourite editor, development environment, mail and news reader (Gnus) and WWW browser (W3).


the GNU Image Manipulation Program


The GNU Network Object Model Environment


The Gimp ToolKit


The Persistence of Vision Ray Tracer

Valid HTML 4.0! Graphics by gimp Powered by Emacs (c) 1999 0rfelyus