Dimajix Developer Blog

It is Winter again in Frankfurt! During the last 5 years that I have been living in Frankfurt, I never experienced that much snow in the city as today. Although people from other regions might say that 4cm are ridiculous, but for Frankfurt, that is a lot. SO I guess I will go for some bicycling later, together with my camera and take some shots of the forest in white.

This week, there haven't been many updates in this blog, my apologies. I have been thinking about some WLAN problems, I have been working on frustum culling (which is almost working perfectly, I only have to refine the frustum-box-intersection test) and I have encountered some difficulties, which seem to be related to my last Nvidia driver update on my notebook.

This last topic is really strange: Suddenly one of my test programs stopped to work on my notebook with Nvidia graphics, although it is still working fine on my PC with ATI graphics. I tried to debug the application, and I found something really wired: The program allocates a bunch of index buffers, each getting an even id on the Nvidia graphics card. Then the optimiser tries to merge all index buffers by allocating a new one - which for some odd reason gets an odd id from the driver. After releaseing the first bunch of index buffers (which aren't needed any more, as their content has been copied into the last one with the odd id), the big optimised index buffer seems to be deallocated, too by the driver.

On the one hand this seems to be a driver bug, but on the other hand I cannot believe that such a simple OpenGL command sequence will evocate such problems. Maybe I try to tackle it down, by writing a much simpler application that tries to reproduce the odd behaviour of the driver. Or I simply reinstall an older driver and see if the problem persists.

Kaya

So there have been a couple of days without an entry in my blog. I really wanted to update it on a frequent basis, so here a little status update, what is happening "behind the scenes".

1. My new notebook was WLAN support, so I was thinking that it would be nice to have a WLAN access point. First I was considering to build one myself based on a little ITX form factor PC running Linux that has a MiniPCI slot. So I bought a MiniPCI Atheros based WLAN card, but it does not seem to work correctly, maybe simply because I still don't have an antenna (it is not so easy to get one that has the right connectors and isn't too expensive).

Currently I am considering to buy a Zyxel ZyAir WLAN Access Point. These are a bit more expensive than the ones produced by Netgear, D-Link etc, but Zyxel products offer very nice professional features not found at the other products, unless you spend a lot of money for 3Com, Cisco etc.

I already have a Zyxel Prestige 310 Router for my DSL access, and although it is already getting old, it still rocks. It has such nice features like a serial console, a telnet interface which is far more powerful than the web interface, multiple IP adresses (which enables different subnets), etc.

2. I am still working on two subprojects: One is to get culling done (I made some huge progress concerning view frustum culling) and the other is to get some more interesting effects out of the spring systems.

Kaya

For a while I was thinking "Hell, I already wrote about 50 entries for this blog, but there aren't that many people reading". Now I was sure there must be some sort of yellow pages for blogs in the internet, where I can advertise mine. After googling aroung for one or two minutes I found an entry in another blog that gives an extensive list of blog and rss search engines.

If you want to submit your blog to such engines, simply go to Ar Paparo's Big List of Blog Search Engines.

Kaya

While browsing through the endless space of the internet, I found a page containing some nice models inspiried by Stanely Kubrics great film 2001: A Space Odyssey. You can download the models at http://www.strafe.com/2001/and play with them - expect the next demo to be using some of these models.

I have to admit that I never saw this film completely, the plot was always a bit too slow for me, but I am still planning to take some time to enjoy the whole movie some time...

Kaya

Merry Christmas to all Readers of my blog!

This picture actually was taken two years ago from the window of our appartment, but I used it for two reasons: There is no snow outside today and they replaced that church with a new and ugly one.

Merry Christmas!

Kaya

While working on my font renderer, I needed an ASCII chart in order to interpret special characters for supporting colours... I found this nice chart on the web and it remembered me of the golden days of DOS many years ago... at that time I almost knew many control codes by heart and I always had a printed version handy...

And you could draw so wonderful ASCII GUIs, it was a really different epoch of computers.

Kaya