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Testing irrEdit Global Illumination

As I already blogged, I implemented global illumination into irrEdit last week. Unfortunately I wasn't able to really test it out and didn't know if it really worked. So I just built a test scene using anim8or and lighted it with my irrEdit development version. The result:

The same scene rendered using direct lighting (left) and global illumination (right). This feature will be included in the next version of irrEdit.

Looks great, IMO. I wanted to test if the color bleeding worked using the red cube. Some texels on the floor are a bit more red, but I'm not sure if it really does work as I wanted it too. So I built a better test scene:

Again, a scene rendered using direct lighting (left) and global illumination (right).

Obviously, color bleeding works as expected, yay. As you can see, there are some artifacts, maybe really something Steve already suspected in a comment on the previous entry. But I'm happy it looks like this so far, hope I've some time to improve this until the release.

Playing around with Global Illumination

Currently, I don't have a lot of free time, because of some changes in my private life. That's why I don't have much time to work on Irrlicht, answer mails, blog, etc. Sorry for that. But yesterday (national holiday) I grabbed some few free hours to play around with Global Illumination: I implemented Radiosity into irrEdit. The following screen shot shows the first result:

A scene lighted with a single point light, calculated with two different lighting algorithms

It doesn't look very impressive yet, I know. Especially if you compare the calculation times: The scene on the left image needed 0.3 seconds to be calculated, the right one about 40 seconds. And this gets even less impressive if you think that you can produce nearly the same result by using the fast version with a shadow opacity value of about 0.8 (which is the default value in irrEdit currently and has been changed to 1.0 here to make the difference more obvious). In addition, I'm not very sure if the result is 100% correct. I didn't make a lot of tests yet. But it's a first step.

I still have to play around and adjust some stuff in the radiosity renderer, but it works. The cool thing about it: It already theoretically can do nice things like color bleeding and area lights. Another cool feature: Everything is currently implemented in software, everything is running on the CPU, and I already prepared the renderer to run in multiple threads, on multiple cores. But I also prepared it to utilize the GPU for its calculations, just a few dozen lines need to be added to let the renderer use those crazy fast graphics hardware available today.

Me, the scientist

Ever been mentioned together with Xiao D. He, Kenneth E. Torrance or Robert L. Cook?

Cool, my work Einige BRDF Modelle is being cited in the diploma thesis of Jing Qian, 'Generierung, Verwaltung und Verarbeitung von bidirectional Texture Functions (BTFs) zur photorealistischen Bildgenerierung mit komplexen Oberflächenmodellen' (hu!). Finally it was useful for something. :)

Documentary Recommendation - "Press For Truth"

Nothing on the TV this evening? Try this excellent documentary about 9/11, directly from google video, duration: 1:24h. Shows the facts in a more objective way (than sometimes usual on this blog) and IMO the incredible incompetence of the politicans as well as the strange selfcensorship of the media after 9/11. One of the interesting buzzfacts presented there which I didn't know yet:I think this shows the real problem with 'the war on terror' very well.

Gamedev.net surprise

Funny, I just browsed gamedev.net and was surprised to find this irrEdit 0.5 release announcement on the front page. Thanks for posting :)

IE 7 released

IE 6 was released in August 2001. Now, only some few years later, IE7 (although not available as german version yet) has been released today, and I played around with it a bit. Nice tool. Some things I noticed:
Anyway, a nice new browser, finally the average user has tabs too. But I'll stick to Opera nevertheless.

How to get rid of brain damaged lawyers

As you may know, there is this lawyer who frequently sues game developers because he asserts their computer games make kids behave more violent. He even claims it's the fault of the game developers that those violent incidents happen from time to time in schools, where a pupil runs amok and shoots or kills other pupils. This topic has been discussed a thousands of times and fortunately most people agree that this guy simply is a total dumbass and only wants to generate
publicity. Currently, there is a new case where this lawyer sues Take Two/Rockstar Games before their new violent game even reached the shelves. And as usual, all the media is reporting about it, ranting about the fact that this guy will never stop.
Of course, there is a way to stop him: Just stop reporting about it. It's not easy for the magazines and websites doing this, I know. It's a nice and funny topic, and a lot of readers will comment the article and start the default games-are-bad/lawyers-are-stupid discussions about it. People want to read stuff like this. But maybe the media could start by simply not mentioning the name of this lawyer. Wouldn't this be an idea? It's just how you would handle trolls in discussion boards. Heise for example did this already and is simply talking about 'a lawyer' in their article. Nice, although I don't know if this was their intention.

Weekly link list

Here's a short excerpt of what things have been reported last week, most links stolen from fefe as usual:
Sometimes it's really difficult to choose what to put on that list and what not.

irrEdit 0.5 released

I just released irrEdit 0.5. It includes some new features, several bug fixes and a few added user requested features. Have fun with it. It now looks like that:

irredit 0.5

The scene loaded in the shot shows a level from Arena, a game created by Marko Jelen/Drunken Knight Games using Irrlicht. The level has been lighted with the irrEdit built in lightmapper. Here's another one:

BTW: Thanks for the overwhelming interest in irrEdit, it's quite motivating. :)

Some user interface clean ups for irrEdit

Lets face it: The user interface of irrEdit is ugly. So I updated it a bit. Subclassed some widgets, changed some colors and icons, adapted some 3d elements. The change is not very obvious, but if you are using the tool, it feels a lot more clean now. Here's a shot:

But just wait some days, I'll release irrEdit 0.5 with some other nice new features in the next few days, so you can try it our yourself.

Battlefield 2142 Demo

Anyone tried the Battlefield 2142 Demo which has been released last weekend? On my PC, it's nearly unplayable. I get about one frame every 2 seconds. Even after reducing everything to the minimum details. What I've seen just looked like Battlefield 2 with new textures and 3D models. But maybe I'm wrong. Need to upgrade my hardware soon.
And BTW: Is it just me or isn't 1 GB a bit too huge for a one level multiplayer only demo? Especially if there is only one download sever in the german area, because they bought the exclusive right (which again seems very useless IMO)?

Network cable, your flexible friend

I've about 50 meters of unused network cable lying around in my appartment, and don't know what to do with it. I'm using network cables, but since I have WLAN, the amount of it has been reduced very much.
Yesterday I had to do the laundry, but unfortunately the clothes horse was full due to bad coordination with other residents here. And finally, I found some use for the network cable. I strained it three times across the whole room and it served well its new purpose. Although AK and MP already demanded it, no pictures are going to be shown of it (also because I'm trying to get rid of "AH! the Bolzplatz-Shirt again!"-comments :) ).

Lightmap generator bug hunting

To do some real world tests and improve the lightmap generator of irrEdit a bit, I modeled a small test level and placed a lot of lights into it. Unfortunately after about the 10th import of 3D data and the 20th added light, all new lights started to get 'dark' somehow. But only when using Direct Lighting, lighting without shadows had no problems. It looked like this, the light in the middle has the same brightness as the two in the background, but it influenced the scene only very subtile.

That was pretty strange. Because the level was quite huge already, and in the last 3D data import I had seen some very degenerated triangles in the geometry which I didn't create, I suspected some weired geometry to make the irrEdit collision engine (simply a collision manager optimized for raycasting) go mad. So I plugged it out and replaced it with the irrlicht buit in collision manager. The result needed some more seconds to calculate, but it was the same. Strange.
Then I reduced the test scenario by creating a new scene, importing the part of the mesh where the problem happened, placing lights at that positions and retried. The problem disappeared. Confusion. I loaded the original scene, reduced it to the same test scene by deleting not used parts but the problem still was there. More confusion.
Ok. So, why the hell didn't the light rays of that single light reach the walls? Idea: Because fortunately we are using a very flexible 3D engine under the hood and this is possible by adding only one line of code, lets just create a small white cube at the vertices of every triangle hit by the light. Just to see where the light will stop. Result:

Do you see it? All light rays stopped directly near the light! And even more strange: They form the shape of a cube! I mean, I would have understood it if the white cubes where arranged like a sphere or something similar, but a cube exactly enclosing the light? Unlikely.
And now I knew. The problem was not a bug. It was a feature of irrEdit. Stupid me. And somehow I had clicked and enabled it for that light:

In irrEdit it is possible for every object to occlude the light. And 'all objects' of course also includes lights. Which is pretty senseless, a light occluding itself makes it a bit.. ahem, dark. Shadows in irrEdit with directLighting have an adjustable opacity value, and it's at 0.8f by default, which caused that light not to be 100% dark but lighted the scene very subtile.

Conclusion: Cool, I don't even know all the features of the product I wrote myself. To prevent such a situation for users and for my stupid self in the future, and because it doesn't make a lot of sense I now disabled the possibility to enable this feature for lights.

Links into the world part III

What happened last week, via fefe: Previous entry of this series.

UFO sightings

I really like youtube.com, you can do a lot of funny stuff with it, and it never was so easy to search and watch short movies. Recent example: There are some great videos of UFO sightings available there, like this one or this from bulgaria and this from london. This one looks interesting too. I think those guys from sarajevo should have taken the trouble to improve their version a bit, because it reminds of the old school horror movies too much. :)


Looks like I am an IT-Freak. And Judoka. According to a big daily Austrian newspaper, diePresse.

If you bought that newspaper last weekend, maybe you've seen a short interview with me in it. If not, and you are interested, it has been published on their website as well so you can read it there, if you speak german at least. It was my first interview with a real newspaper, until now I only did interviews per email and with websites. It was fun, and also a bit strange, because the photographer took about dozens of pictures from me, only for that small picture in there.
The article itself is nice too, as far as I can tell. Some things written in there are not correct, but who cares. Hey, its an interview with me in a real, printed newspaper, and that's pretty cool. :)

I'm not welcome in this country

Yesterday we had elections in Austria, the country where I live. 15% of all people voted for parties which mainly advertised with horrifying slogans and pre-election promises against foreigners. Interesting to know what every sixth person on the street is thinking about me.