The blog of DAVID KOUŘIL

A trip to the zoo

I’m writing a diary on my computer that comes in real handy when I write things for the blog. It usually seems that there’s not much happened and I have nothing to write about. Then I look at the diary and see all kinds of stuff I did, or things I thought about…and bang, there’s your blogpost.

Like this week, we had a jam session with colleagues. Apparently, a lot of researchers play some musical instrument (myself included). So we got together and made some noise. We also drank which didn’t go well with the playing that much.

I experienced a little bit of crisis this week too. I felt like I didn’t really get a break ever since I finished school (and the sprint to that was taxing by itself), and even though I was working on a lot of things, I didn’t really have much to show for it. That was my impression at least. Of course that’s not true, but in the moment it was an overwhelming feeling. I’m really looking forward for our vacation in Greece in 22 days.

I like being disconnected. That’s when I get into the right headspace and think about important things, ask important questions, and figure out what’s important to me. This get’s easily lost in the day-to-day, when the stress and emotions are the primary drivers.

I got a bit of taste of that this weekend when we visited my parents in Czech Republic. We went to the zoo and just chilled. Of course the two days were enough for me to want to go back and work on things. But I take it as a good thing.

Heatwave 2: The Sweating Continues

The extreme temperatures continued this week.

I took Thursday and Friday off, to spend some time with Gabi and also chill out for a bit. Our vacation is still one month away.

We went for a swim in Alte Donau and for a walk.

I really need to spend more time outside of the apartment. When I have nothing to do I’m just easily bored. There’s only so much work I can do in a day and when I have all the free time I can I don’t use it very well.

Being outside makes everything feel better. I don’t know if I can describe the feeling…it’s like you are a part of it, part of the city, part of the world. You are actually doing shit instead of just looking out of window and trying to figure out what to do.

Also: I cooked this deliciousness:

In the middle of a hot summer in Vienna

It’s consistently hot in Central Europe. I definitely like it better than winter (I hate being cold) but sometimes it’s annoying when you sweat through a t-shirt just walking few steps to a store. Our apartment doesn’t have air conditioning—it’s not very common in Czech Republic and Austria—so we are experiencing the heat wave pretty intensively. In the office we do have AC, but it’s 3 of us there and it’s hard to keep the most comfortable temperature for everyone. It makes me wish I had an office for myself a little bit.

Most of the people from work are on vacations. On Wednesday I had to go to Brno to get my Master’s and Bachelor’s diplomas translations. Ticket machine broke while printing my public transport tickets, then the bus back to Vienna had more than an hour delay. But I got the translations so I would say it was a success.

On Thursday I finally submitted the PhD admission (that what I needed the diploma translations for). I almost left the study department because there’s been such a long line of people waiting. But fortunately it moved pretty fast and I submitted everything successfully. Now I have to wait few weeks for the answer if I can do the PhD at TU Wien.

On Saturday we went on a small bike trip/hike. There’s a hill with a castle, or a church or something, that you can see from the city. I’ve wanted to go there since I got here and we finally did that. The route we took was pretty steep but the view from the top was worth it.

Looks like our vacation plans are forming! Gabi has been going through flights and booking.com and she’s basically the one planning the whole thing. She found some quite cheap plane tickets to Kalamata and we bought them. Just like the last year, we will pick the accommodation later, rent a car, and just go on our own.

Talking about vacation makes me realize that it’s almost a year since I started writing the blog. That’s cool. And although I’m not breaking any view records, I have no plan to stop. Looking back, seeing the photos, and reading about the things that we’ve done, or what I’ve been thinking, is just too much fun!

Things slowed down

Last week was veeeery slow. At least to me it seemed. I think it’s because of the contrast to what was happening the week before.

Many people at work are having vacations and I didn’t realize how much it influences the general working morale. I thought I’m pretty self-motivated. Me and Gabi (well mostly Gabi) are looking at vacations too but it’s hard to decide. Last year was the first time I went to a holiday at sea (we went to Kefalonia) and we had the best time ever. I’m afraid that nothing can live up to that. But we want to go in September anyway so I guess we have some time to pick something.

Usually when I have some downtime (nothing huge to worry about), I have a bad habit of thinking and re-evaluating things. Most of the time it’s work-related. Side projects work I mean.

About my side-projecting: I need to have a mission. I need to be learning new stuff. I’ve been like this for a very long time. It gives me a sense of working towards something, sense of getting somewhere. I don’t think it has paid of yet (and maybe if I applied myself that much into the main thing that I’m doing it would be better) but I need to have this kind of distraction. It keeps me excited about programming.

I have some projects that I’m trying to finish. I have things that I’ve committed to learning. But as it happens sometimes, I started to think if I should maybe stop doing this and start learning something different. Javascript in this case.

I get the benefits and why it’s so popular right now. It’s very easy to make something in it. It’s nice that it work in browser. But I just don’t like Javascript. I’m used to “traditional” programming languages like C++. It might be that I’m becoming the stubborn programmer who’s against doing things the new way.

I believe that there are many applications where you just can’t and shouldn’t use JS (and I believe that those are the kind of projects I’m aiming to do). But because it’s so easy to use and show, you end up seeing JavaScript projects everywhere, and it makes you feel like you’re missing out on something if you’re not on this hype wave too. And I don’t think anybody likes to feel that way.

But I don’t want to be complaining here. It’s just something that has been on my mind.

Hungary and Pohoda festival in Slovakia

What an absolutely packed week!

Leaving Vienna on Tuesday, I was going to Balaton in Hungary with our work group for something that’s called Closed Meeting. It has two purposes: a) talk about organizational stuff for the next year, and b) get drunk with the guests we invite (people call it networking).

The real adventure started when I departed on Thursday morning. I needed to get from Balatonszemes, Hungary to Trencin, Slovakia. This meant three trains and a subway ride in Budapest.

I am not very well-traveled. I was used to going on vacations with my parents around Czech Republic. I was 23 the first time I went outside of Czech Republic (and Slovakia, I don’t count that as being abroad). Going with a train in Hungary and getting around in Budapest was really something new to me (don’t laugh!).

I was surprised by how much I actually got used to being in Vienna, how many of the signs and words in German I know already. Hungarian—totally different, not catching anything.

This was my route:

I’ve got to say that mostly everything went well. I did miss one train in Budapest because of the queue at international tickets office (and because I was waiting at a wrong place at first) but that “only” meant waiting two hours for another one.

I left around 10:30 in the morning from Balaton and arrived around 20:30 at the festival in Trencin.

We had a tent rented for the festival and I wasn’t very well prepared for it. I didn’t think it would be so cold in the night so I didn’t bring a sleeping bag, just some warm clothes and a blanket. I am not a smart man.

We experienced two thunderstorms while hiding in the tent. It was actually pretty nice. I recorded the sounds, I don’t think I will have the opportunity to listen to a storm that closely any time soon.

The absolute high point was the headliner on Saturday night—alt-j. If I had to name my favorite band, alt-j would probably be it. The performance was ace. The only thing is that I kinda expected a little bit more emotional experience. In the end, it’s just three people playing music you know in front of you. I felt that I had more “spiritual” connection to their music while listening to it alone at home some evening. But that’s absolutely not something that’s degrading the experience in any way. For me it was a great show and an item crossed out off my bucket list.

I have some bands that I discovered at Pohoda and I’m starting to build up a spotify playlist which I plan to share soon.

I am really glad that we went. It’s something you can’t really appreciate while you’re in it, worrying about having to go pee, then getting water, then going pee again, hiding from sun, hiding from rain, and trying to survive in the middle of all the (mostly drunk) people. But once it’s over you kinda miss it. I guess you really need to see the discomfort as your friend. That’s where the real experiences happen.

Getting ready for a busy and exciting week!

Gabi was gone almost this whole week, she’s on a yacht sailing trip in Croatia with her colleagues.

I’m getting more and more excited about next week. Two things are going to happen:

  • we (the VisGroup, the group where I work) are going to Balaton in Hungary for a “closed meeting” which is a gathering of our group and some guests where we talk about stuff. And then,
  • we (me and Gabi) are going to Pohoda festival in Trencin, Slovakia.

I will be leaving on Thursday and going to Slovakia straight from Hungary. I’m counting on the trip itself to be an adventure.

I’m incredibly hyped up for Pohoda. The biggest headliner is alt-j, but I’m looking forward to the festival atmosphere in general. I’ve been there in 2014 I think and I loved it. I hope we’ll have similarly good time this year.


I’ve seen two things that I very much liked and they had some impact on me:

  1. a documentary about 3D printing and the business around it: Print the Legend.
  2. a GDC talk about the development of a game called Thumper.

The 3D printing documentary was interesting mainly because I don’t really know anything about the technology and the business of it. So it was interesting to see how it all got to be.

The Thumper talk was game-changing for me. I really love that guy’s calm approach to all of it. He’s not complaining how hard it was. He’s just explaining the journey and talking about how they got through. I like the simple approach. Just put something on the screen. And iterate. I like the idea of learning as you go but lot of the time I get stuck and I think that I’ve arrived at an impossible obstacle. But seeing them make this game made me think about the way I approach stuff and be more of a “deliver-it” programmer. I want to deliver things, not to do them right and overengineer it.

That’s it for today, see you next Sunday.

The week when I was sick

I was sick this week. I wrote about that already. It means however that there’s not much to say about my week other than that. I stayed home and I slept a lot.

The weather has been extremely hot, 35 °C at some point. It’s hard to say if it was good or bad that I didn’t go anywhere and was at home the whole days. I guess it was a good thing. Although the amount of sweating I did…

I remember last year when I was sick like this. It was very similar—also in summer (right before our vacation in fact) and I was also hit so hard that I could barely move. And the same as last year, I didn’t drink any coffee and I’m thinking about continuing with that. I haven’t had any coffee since Monday and I kinda like it. But I have to say that being at home makes it very easy to have a nap after lunch (instead of the cup of coffee).

The only thing about drinking coffee that I don’t like is that I don’t want to be dependent on something so much. I want to be able to focus and work whenever I want, without the need to get some caffeine before I dive into something (that’s a state of mind that I’ve been gravitating towards lately). I guess I’ll try to not drink it for a while and see how long I can do it.


On Friday we went to Donauinselfest. It’s a free music festival that takes place on the island in Vienna. We wanted to see Cro. We did and it was awesome! I really really liked it. Although being sober at this type of an event is not that much fun.

I’ve got to say that I’m very much looking forward to going back to my normal functioning routine.

Had being sick always sucked this much?

I got sick this week and it’s been awful. I think I got some kind of flu or something. I get sick like this maybe once a year and I have a suspicion that it get’s worse and worse as I’m getting older. This time I got completely smashed. I got headache, runny nose, throat ache, fever, and I was almost not able to move. Maybe it’s because when you’re a kid, you don’t really care that you’re sick. You just don’t go to school.

But as an adult, you have responsibilities. You’ve got shit to do. Maybe that’s why it’s been extra hard for me this time.

Tuesday and Wednesday was the worst, now it’s a bit better. It’s still not as easy to breathe because of the stuffed nose and I’m still coughing. But at least I can stand up for a while.

Also the better I feel the more I’m motivated to go back to my normal schedule, back to working. I really need just a few days to reset, but I can’t spend doing nothing more than 2-3 days.

I got a new phone

My old phone was an iphone 5s which I got in January 2014. I’ve had a lot of fun with it.

I thought that I don’t need a new phone, I thought that I really just wanted one. But now that I been using my new 7 plus, I realized that I actually already needed to upgrade.

I’ve been trying to do more and more on the phone. I’ve been editing photos for instagram on it. I’ve been writing notes all the time at work (and in general). Some blog posts have been written on my phone as well. I want my phone to be an ultimate planing and management tool. And from this perspective, the old 5s just wasn’t keeping up.

The 7 plus is amazing. It’s a shock when you see it for the first time, it looks just way too big. But it’s very easy to get used to the additional screen estate.


I’ve seen an interesting video. It’s Dealing with Performance Anxiety and I feel that, although it’s aimed for performing musicians, it’s perfectly applicable to other disciplines as well. For example, in my field of work you give lectures and presentations very often. And I usually do get at least a little nervous. So there are few things I got from that video:

  • to get nervous is a natural reaction of the body to the stress of performing something in front of people
  • there are three parts to every performance and you need to approach them differently: the training leading up to the event, few hours before the event, and the actual performance. you need to optimize what you’re doing and where your mind is in all of these
  • few hours before: box breathing to calm down, don’t try to catch up on the practice, go through your visual “cues” if you have any
  • when performing: you will always play/talk faster than when you are practicing, try to keep about 80% speed
  •  weeks leading up: practice the thing, but also practice the delivery: take a video of yourself, imagine that you are doing it in front of people, perform it in front of few friends.

You should definitely go watch the video for more in-depth information!

How not to look for bugs in your code

In the project at work I basically have data that I’m rendering with a very sophisticated rendering pipeline. I was not getting exactly correct results so this week I had to look into that. From my point of view, there were two parts where things could go wrong: the data loading or the sophisticated, complex, error-prone rendering routine. I’ve spent two days going through every single part of the rendering, making sure that everything does exactly what I need it to. Of course everything was fine. The problem was in a code which loads the data from a text file. At some point I thought that this might be the problem but I dismissed it because it was “too much work” to debug.

It was just a gentle reminder of how much I still have to learn. Sometimes I get really hyped up and I’m excited to deliver things. But then I get stuck for few days on one thing and I’m reminded how hard software development actually is. It kinda makes me appreciate higher-level programming languages and other people’s libraries.

I was at my colleague’s “proficiency evaluation” this Friday. It’s a new kind of exam at TU Wien for PhD students. You are supposed to do it some where in the middle of your PhD and basically you show what you’ve already done and what’s your plan for the rest of the PhD. He was the first one to do it in the Vis Group and even though he passed, it wasn’t 100%. I took a lot of notes and I’m going to make sure that I have a better plan for my PhD.

This week were also notifications for IEEE Vis 2017 conference and quite a few papers got through! The one that I was participating on too! That’s good news because more people are going to go to Phoenix this autumn.