The last weeks I've crawled the web, I've read tons of stuff, not all related to programming, but some sites in that respect are real gems. I will quick-post some of my favorites of my journey (I'll probably miss some, but will edit this entry later then):

Just written a little story about me for the people who wonder who I am or what I am doing.

whoami

My name is Sebastian Mach (the 1983 a.d. edition), by some known under the pseudonym 'greenhybrid', hence the URL of this site phresnel.org, or simply 'seb'.

I'm interested in tons of stuff, but rarely find the time to explore it all. The biggest interest in charge of all others is definitely programming, or simply 'coding', which is a slang-word for some people (but not for me and most of the others who know me). To make the circle sharper, my main interest within the discipline of coding is graphics-programming, especially Ray Tracing. For those who don't know what that actually means, simply speaking: I am not someone working with the graphics software, I am someone who develops it. (okay, okay, I've never done anything very user-friendly, but technically that example fits into the concept).

Well, now follows a short summary about what I have done the last years in my favorite discipline:

• 1999-2004: the time of not being connected to the world through some cables

  • the dark age, I don't remember exactly (from 1999-2000?).

    What I remember is that I came in touch with an old and crappy and totally virused 286/32MHz, as far as I remember, with DOS and Q-Basic, which was the only running 'program', so I began 'it' (what a lucky pure accident).
    Armed with what is called Q-Basic, a friend and me had brutal and disturbing "coding-battles", first experiences with variables (later we even became aware of the fact that a variable's name can be made up of more than just one letter, yay!), goto's, if's and so on...
    A pity he then gave it up for some reason, while I was getting more and more knowledge about things like arrays and file-i/o (actually, I knew file-i/o at first and used that to temporarily save and load dozens of data-packs, again and again for each frame. Not kidding, I just did not know about something like 'arrays'). And all my sprites then were hard-/handcoded couples of pixels (their positions saved/loaded in an file each frame, for sure), wheee!
    ...phew, lemme get some air and a cig-pause (yeah, I know, bad habit, and sorry for my bad writing style at this point, really rushing through it due to time constraints)...
    

  • 2000-2001 (? not exact date).

    From time to time the voices came: C, C, C, ... C!. A lucky accident then wanted me to grab a game-programming-starter-box (with the evil MSVC6 inside, plus Marc Saltzman's book "Game Design", and some other stuff), so I finally got a C/C++-compile and dev-environment (which I used for years then, nothing wrong with Redomd at that time, syserrors(C) were simply "normal").
    So I actually learned "true programming", without gotos and pasta. It all looked so cryptic and cipherish...but I was hard enough to withstand my antiknowledge. A lot of delphi'ish programming: Add Button, double click it, write source, don't understand what is going on...Slowly I got into it, became aware of typedefs, structures, classes, and hey: pointers! The latter one is maybe one of the largest hurdles for every newbie-coder. But once you got it, it is no problem to use things like "int foo( int **x ) { free(*x); *x = 0; }".

  • approx. 2001-2003 (low entropy time)

    I've done mostly Direct X/Graphics coding. I actually started with OpenGL, but no internet and low documentation in the MSDN doc (while I had a DirectX 6,1 SDK with proper documention in the above mentioned starter-kit) made me skip it.
    I called this section low-entropy time because w/out an internet connection and double-w/out money (for buying books) gaining knowledge is really a mess.
    Here and there a scratchy project like a very small ray-tracer or a never ended bomberman clone in 3d, called xploderz, with some funny elements (hide/bomb/run, a bit of MetalGearSolid). Actually I have also tried to understand the A*-algorithm, but with just a poor article in a pc-magazine it was impossible to me.
    (quick note to me: expand this section a bit, lookup old backups to achieve this)

• 2004: break! or: The time of not coding because of the Wehrpflicht

  In short: The Bundeswehr called, I became a proud member of the Bundesmarine, i.e. a "Signalbetriebsgast". That means I knew the morse alphabet, I could morse (morsing is not just the standard alphabet, but also a lot of "special signs" for things like "End of Conversation" and so), I knew the whole international flag-alphabet (and a lot of signals), and I was able to do some "Sprechfunk" (I guess it's radiotelephony in english).

  After the so called "Grundausbildung" in Bremerhaven at the Marine-Operations-Schule (the first three months, were you learn the basics all soldiers have to know [run, hide, shoot, duck and cover and more] plus the specifics of your "job" there) I went to Hamburg, where the frigate F212 "Karlsruhe" waited for me in the dockyard "Blohm+Voss" (actually the same dockyard where the "Bismarck" in WWII was built, and I saw exactly it's dock plus a small part of it's plating).

  Three months or so later, me with two golden stripes on my shoulders (meaning "Obergefreiter" [Lance Corporal or Private 1st Class, in english, I think]), we then leaved Hamburg to get to Wilhemshaven, the "main base" for the german frigates. A nice town at the Jadebusen, not far from the north sea.

  I don't get into more detail now, you would be bored (or I would be hung ;)), but one thing that brandmarked itself into my synapsery was the approx 12 (ideal case), but up to 16 (the general case, Deutsche Bahn, you might have heard of it;) ) hours of train time in total, per weekend...

  After those 9 faboulous months I will never forget I had a lot of free time, and I played "GTA-San Andreas" in the late 2004.

• 2005-today: the time of enlightenment, finally having an internet connection, yay!

  In the soon 2005 I had to acclimate myself to coding again. And I wrote the root-engine, a never ended story, but the ladscape part of it was really good! But to save time here, just be aware that it has it's own blog here.

  The biggest thing that happened 2005 was Julia! I let this stand alone at this point. Awesome.

  Finally having an internet connection in late 2005/soon 2006, I surfed the web and found some amazing stuff about Ray Tracing, so, at first just for fun, I wrote a small ray-tracer again: glass, glass++, gladius and now xitrace (all with their own respecticve diary here) should tell the rest of my story so far. Plus a bit of Fractals, L-Systems and Compiler writing. What they call internet is amazing, since it caused my most creative year ever, and is going on to give me knowlede. But enough of that now, all my work since January 2006 is on this site!

  If you really reached this point in the story (or just have read a small part of it): Thank you for reading!

some more short infos about me (grabbed from my deviantart-page)

• Current Age: 23
• Current Job: Applications Developer
• Current Residence: NRW, Germany
• Favourite movie: gladiator, saw, cube, full metal jacket, saving private ryan, black hawk down, bands of brothers
• Favourite band or musician: system of a down, rammstein, slipknot, korn, aphex twin, ochre, felix laband, autechre, and more...
• Favourite genre of music: rock and idm, I also like irish folklore (remember Gangs of NY, huh? ... how cool)
• Operating System: Debian GNU/Linux
• MP3 player of choice: Amarok
• Shell of choice: bash
• Favourite game: all time favorite: Civilization III, Shogun/Medieval/Rome: Total War
• Favourite cartoon character: Homer S. from Springfield, somewhere in the US
• Tools of the Trade: Anjuta, SciTE, gcc 4.1, bison/flex, my fingers, Kaffee, Neurons

A Year of Onlineness

"Hallo zusammen und willkommen!". Those were the first words on this very homepage. It was Saturday, January 14, 2006 (there was no english version from startup, but more on that later)
Now:

Thank you all for sharing your precious time here, thanks for your interest, for everything. Special thanks go out to my beloved Julia, for giving me the time to code, and, especially, for her interest in my work, I love you!

Now follows a short summary of my programming work of every month, including some screenies, I hope you also enjoy that.

January: Startup, or Hallo zusammen und willkommen!

Startup. I finally have a little homepage again. At that time, the whole page was written in pure html. The design was hardcoded. And I had not much time to program.

Nothing special going around regarding my graphics-coding except for the root-engine.

February: Internationalization, or Hey there, it′s 0112am and I′m kinda tired....

Startup of the english version. Duly for Feb 01. And dude, I was abs(tired), bet.

Furthermore, I was tired of all the html-hardcoding. So, not much coding again except for the php-migration of my homepage.

March: A new passion, or want a glass of liguid and sour sauce?

Ray Tracing? ... Yes! The beginning of my efforts on Ray Tracing. That was the start of a new passion. I posted some images on devmaster.net and the guys there were talking in some cryptographic jargon about "acceleration structures", "MRays per seconds" and I dunno what else. I felt like a beginner. So I wanted to show them that I am not (for sure I actually was one regarding Ray Tracing) ;)

I've never read that much papers and never learned so much in general like in the year 2006. Ray Tracing, or the "glass" ray tracer, was the initializing big bang for that. And tbp (ompf.org), who "offended" me (just kidding dude) in my glass-post on devmaster was not innocent for my incidental ambitions.

April: Accelerated Ray Tracing, or The key is kd

Awesome: Ray Tracing with a few thousand polygons. Builduing a kd-tree was damn hard for me at that time, and it was damn hard to get a clue about the traversal mechanism Wald mentioned (Actually I was using my very own traversal algorithm); but it was a big motivation that the image at the right (below) took only 4.5 seconds with three colored lights and about 20k triangles.

But for some reason, it does not look trés realistique...

May: Global Illumination, or at least a glimpse on

Knew not much, instead done much. I did some particle-tracing and traced some images with about 10000 samples per pixel. If I had read Kayija's paper first....

On the other hand, my particle-tracing helped me a lot to understand the basic physics of lighting, even if I only traced primary bounces.

I also gave a try on finishing xploderz. I have to say, the code was kinda pasta. At first it looked good. It was fun to reactivate an older project and to add some neat features.

June: Photon Mapping, or memory, a lot of memory

After reading Jensens paper on Photon Mapping I had to implement them to get some caustics. I was struggling with global illumination over and over. I did direct lighting via Monte Carlo, and indirect lighting fully by Photons... I should have known better. But failing here means succeeding in the future, I think. At least the images did not look too bad.

Afterwards, it was lycium who told me he doesn't "like photons [...] because of the smeary look". I skipped further work on that topic and started a pure path tracer later...

I found some guys who started the scripting of some levels for xploderz. We also had a little forum with some active discussions. It looked really promising. But it's the time, the time is rare. Too rare.

Nevertheless, Thanks deja_vu, LJ_1102 and jph for your level-designs and Hanatarou and Broesel for your awesome tunes!

to be continued...

So far, thanks for reading and excuse me for my bad style of writing, I really rushed through it. The latter six months will be summarized in some days, see you later o/

Hey there and welcome!

So I have to handle the interesting things one by one. My implementation curriculum of the last weeks:

• performant SAH-Kd-Tree
• MLRTA (not yet perfect)
• Perlin Noise landscapes with ray marching, later with ray tracing
• L-Systems (just got the basics in a 1 1/2 hour coding session and rendered a little Sierpinski Gasket using it)
• other not so relevant things

• Advanced L-Systems (it's a simple but (I mean it) mighty system, like Perlin Noise) for ...
  • ... plant generation
  • ... city (yes, city) generation
• Further optimization of the Perlin Landscape (don't even try to global illuminate the terrain at the moment)
• other not so relevant things

Lot to do, lot to learn. See you!

Welcome folks!

question: What does it mean when the linux operating system does not boot up, saying "kernel-panic"?
answer (just two words): Hardware. Problems.
consequences: Failed memory reads/writes, or, to say it cleary, an unmountable harddisk-partition (namely "/home"), meaning my works of the last weeks are NULL.

I decided to write a new ray tracer from scratch, a performance-oriented one, not object-oriented (its not 8k-democode, the design is still object-oriented).

As you may have considered, the design of the page changed from infernal flipcode darkness to a lighter, modern one. How do you like it? Feel free to give feedback via the contact form.

Now have a good time exploring this page, see you later!

... and this site will have six months on his back. A lot of things happened since January 14, and because of that there will be a little surprise.

What are you doing these days?

What happened to xploderz?

Other activities?

Greetings ...