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Kreso and Bubble Trouble, a 20-year tale.

We sat down with Kreso to talk about the early Flash days, all things Bubble Trouble, and working with Poki to bring the hit Flash series to HTML5 so it can continue to be enjoyed by millions!

Kresimir Cvitanovic (a.k.a Kreso) is a Croatian game developer most notable for the hit web series “Bubble Trouble”. Having started coding websites at a young age, he went on to create the series just as he was starting college in 2002. 3 games and nearly 20 years later, support for Flash ended in 2020 leaving the future of the games uncertain. Converting the games from Flash to Phaser was no easy task but two years later, BT3 has been converted to HTML5 and joins its two predecessors on Poki. Now with over 5 million plays just in the last year, players are reliving the good ‘ol days.

I felt concerned what would happen with web games after Steve Jobs announced dropping Flash support many years ago, just as the web games started to bloom. Today it turns out HTML5 is versatile enough, and with the rise of bandwidth and WebGL games, web will be more and more dominant I hope.

- Kreso

Born and raised in Zagreb, Croatia, what was the video game scene like when you were young and how did you get into coding?

Image of Kreso and his friends winning the Championship in 1998 — Team TresnjevKAOS. Kreso is standing on the right while his 6 friends are beside him
Kreso and his friends winning the National Championship in 1998 — Team TresnjevKAOS

When I was 10 years old, the gaming scene was just arcade stores. Most of the video stores also had arcade machines so me and my brother spent lots of time playing those. About 5–6 years later, local cyber cafes became more popular and me and around 10 friends came together to form an Esports team. Each of us specialised in a different game, I was the Warcraft 2 player. There was a Croatian National League which lasted for only one season but our team won!

My father was really into computers as it was a place of work for him so I would get some time on it here and there, usually messing around with drawing and animation, eventually finding Photoshop and 3D Studio Max. In college I learned programming which is what I felt opened the door for me to create what I really wanted; a fully interactive experience.

Bubble Trouble came out on Newgrounds on January 28th 2003 (almost 20 years ago), can you tell us a little about how you came across Flash and the early stages of the release?

In 2000, Flash was a tool for making simple interactive animations for websites. It wasn’t that popular since you had to download a special plugin in order to play but I used it for a few animations on the websites I was making. When I was younger, I played this game called Super Pang, a.k.a Buster Bros, on arcade machines. While playing, I was always imagining improvements to the game which gave me a lot of inspiration for the Bubble Trouble series to the extent that when I started programming, I would come home from college and start making my own version of Pang. I remember the excitment of programming a grey box to move left/right when I press the keyboard, then adding shooting harpoons and finally forming a complete game with levels, menus and all.

I playtested Bubble Trouble with my siblings a lot because my whole idea was to make a game that two people can play together. It was so much fun that I wanted more people to know about it so I hosted the game on my college website, posted the link on different forums and a couple of weeks later it was in the national newspaper. I was stunned. After that, people started to play it and I felt the urge to share it even more so I looked for game websites and came across things like Miniclip and Newgrounds. The rest is history.

Bubble Trouble brought bubble popping from the arcades to web browsers, as one of the great early examples of what Flash games could be.

- Tom Fulp, Founder of Newgrounds.com

What was the process of converting the games from Flash to HTML5 like for you?

A timeline showing all 4 Bubble Trouble games and the main character from each, beginning at Bubble Trouble 1 from 2002 on the left and ending with an image of Bubble Trouble Online, coming soon!
A timeline of the Devil from each Bubble Trouble game

This was my first time converting a game and I was dreading the process before I started as I would need to focus on old code that I could no longer play. I wrote all this code personally so I could easily understand it and find better ways to write it. Knowing in advance that I was porting all 3 games, I could plan ahead and write reusable code. I chose Phaser as at the time of doing my own research (2019), it had a small footprint and it was very easy to publish to multiple platforms so it seemed like a fit.

The biggest task was recreating the Bubble Trouble physics engine written in Flash (Actionscript). I could’ve used the default Phaser physics engine but decided to dedicate a lot of time to recreating the original from the game. Even though I was fairly certain most people wouldn’t notice this, I felt I wanted to get as authentic of an experience as possible to the original (matching the speed of bubbles, gravity, character movement etc). This conversion genuinely felt like I am honouring my old games and I enjoyed the process thoroughly, I can even remember repeating to my friends how much I loved working on it at the time.

I make most games using Unity 3D today whose editor is very useful. When I was converting BT to HTML it was nice to get back in the mode of coding where I only see the result of code on the screen. Since BT is 2D there is actually no need for a game engine IDE. I actually missed this, so I was grateful the conversion allowed me to delve once again into a pure coding experience.

You have worked in many teams and companies developing games over the years, what’s it like working in a company creating games versus working solo on a game with Poki as a partner?

The first thing that comes to my mind is working on your own IP. It’s a little, I don’t want to say stressful, but it’s more stressful than working in a company team. As an indie developer, I work with maybe one or two more people and mostly on a freelance basis versus working in a company where there’s always communication and brainstorming.

When I was talking with my friend about feeling drawn to revive Bubble Trouble, he suggested to see if a company would like to revive it with me so I talked to Joep [Head of Game Developer Relationships at Poki] and asked if Poki would be interested. He was very transparent and welcoming, saying that everyone at Poki loves the game so whatever you need, let’s see how we can do this. Working with Poki feels like I have a partner in the real meaning of that word. I feel like you guys are, and I’m not just saying this, really interested, open to hear things, and present. If something is unclear for me about anything from technical issues to payments, it gets dealt with swiftly and professionally as opposed to solving my problem and getting on with your life as quickly as possible. I get this sense that our communication matters, like we are co-creating. You guys are very transparent and give me realistic expectations for my games because you have been doing this for a long time and know what to expect from the game. Also the Christmas swag and socks are a big plus ;) .

Bubble Trouble is one of those evergreen Flash series that will stick to you forever. Kreso did a great job preserving the title for the future of web by recreating it in html5. Keeping all of the elements that make the game great, he kept innovating and even offers something new to his fans by adding a level editor to BT’s last instalment.

With html5 maturing as a tech and other Flash game classics such as The Impossible Quiz, Raft Wars and Bad Ice-Cream coming back to live in html5, web can once again be that cradle of joy and creativity!

- Joep van Duinen — Head of Game Developer Relationships at Poki

The Bubble Trouble series has garnered a huge following since its inception, what was it like having so many eyes on your creation and how have you managed to stay so invested in it after all these years?

I was just happy that people were playing the game. After I added a visitor counter on the page, I could see the number of people that played the game but it didn’t mean too much. One time, I was renting an AirBNB in Los Angeles and the guy tells me he played Bubble Trouble with his sister a lot. It carried a lot of sentiment for him and he immediately called her up even though they hadn’t spoke for a long time. I don’t meet that many players face to face so hearing about personal experience and excitement gives more meaning to my work. These stories are what remind me of the impact the games had on people, even the “f- you, this level is way too hard” emails that usually carry a dose of humor with them!

I had a period in 2008 when the games were very successful and where I was really burning myself out, pushing myself too much. I was very tired and drained all the time. It took a few years for my love of making games to resurface but I learned to slow down and pace myself which I think is very important for an indie developer.

What can we expect from Kreso next?

Headshot of Kresimir Cvitanovic (a.k.a. Kreso), creator of the Bubble Trouble series
Kresimir Cvitanovic (a.k.a. Kreso), creator of the Bubble Trouble series

Next up, Bubble Trouble Online. That’s what’s up man. Two versus two or four people co-op fast paced action. Also I’m testing out some casual games ideas. We’ll see.

I would like to thank Miniclip for being the first BT publisher and am also very grateful for Poki who accepted my crazy idea to do the whole BT series conversion. Finally, I would like to say a special thank you to my beta tester and sister, Tea. Thank you, Tea ❤️ — Kreso

Join the Bubble Trouble Discord for custom maps and updates about all the Bubble Trouble games.

Play Bubble Trouble, Bubble Trouble 2 and Bubble Trouble 3 on Poki.

Interested in releasing your game on Poki? Share your game here.



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