We were recently asked by James Harriman how we handled movement physics in Nikki and the Robots.

James Harriman:

I wondered how you handled the movement of Nikki in your game. Did you make him/her a kinematic body and allow her to be pushed by certain objects? Or is she a dynamic rigid body with enough constraints to keep her from bouncing around?

Sönke, main programmer of Nikki and the Robots:

Well, I am kind of an autodidact when it comes to physics engines so I am not to sure about the terminology. What's the difference between a kinematic and a dynamic rigid body?

But to give some overview: Nikki is just a normal physics object in the scene and interacts with the other objects much like every other object.

The Nikki object does not change its shape. To ensure that Nikki does not rotate, the rotational mass is set to infinity. Controlling of Nikki works through applying forces (or -- in case of jumping -- a momentum) on the object. We consciously refrained from manipulating the velocity or position directly. We hope that Nikki's movements integrate better with the physics and feel much more natural that way. Also, it helps to prevent weird behavior in the physics scene. The downside of this is that you don't have full control over Nikki's movements, i. e. you cannot work with traditional animations.

Generally, this was one of the more challenging things that we programmed for our game. Working on this also really changed my perception of other platformers. In most other platformers, the movements of the protagonist are animated and don't feel really physically natural. Well, at least if you spent some months trying to do it differently. ;)

Please feel free to let us know about what implementations of movement physics you have worked with and which you prefer!

We – the Joyride Laboratories – released the Story Episodes to our game Nikki and the Robots in September. The good news is that we got some really good reviews and customer feedback. People seem to like the game and appreciate the work we put into it. The bad news: we didn't sell as much as we had hoped.

Because of that we have decided to stop working on the game. That also means there will be no further Story Episodes. We would like to apologize to all the people who bought the Story Episodes in hope of further episodes. We shared that hope, but we always knew there was a chance it wasn't going to happen. We are sorry and hope you still enjoyed the game.

What Happens Now?

Despite the date this is not the end of the world. Here is what that means:

• Our website and the online store will stay online for at least some months. So you will still be able to download the free version. If you bought the Story Episodes you can still download them through the game. And you will still be able to buy the Story Episodes.
• We will not work on the game anymore. We won't implement new features and we won't fix existing reported or unreported bugs. (As most of the game is an open-source project that doesn't mean that others can't work on the game. But you probably shouldn't hold your breath.)
• The level server will stay online as well. You can still up- and download community levels.
• We will let you know should we have any plans to discontinue the services.

Any Last Words?

We would like to express our gratitude to all the people who helped bringing Nikki to life. This includes all the people working on upstream projects and technologies (most notably GIMP, chipmunk, hipmunk, Qt, ghc, the Haskell ecosystem and MinGW). We would like to thank the people that helped more directly with creating the game: personal friends, who provided criticism and feedback, our beta testers and Roel "cerror" Heerspink, who provided the fantastic soundtrack for the Story Episodes. At last we want to thank our community: people who built and uploaded levels, reported bugs, bought the Story Episodes, and people who simply played the game. You all have been great. Thank you!

It was an interesting, challenging and rewarding experience to work on Nikki and the Robots. But – maybe most importantly – it was a tremendously huge amount of fun. We are going to miss this.

Nikki and the Robots is now on Steam Greenlight™ and we sure hope that it will get enough Thumbs Up to join the comfortable cross-platform player community soon!

It might end up being the first piece of software on Steam that is open source code and written in Haskell.

Nikki and the Robots Greenlight Trailer

By the way, if you happen to speak German: we have been interviewed by Pixelmacher and will appear for four minutes on German TV (ZDF.Kultur on Monday 26th Nov 2012, 22:30 - 23:00 GMT+1) and more material will be available on pixelmacher.tv for two weeks after that.

We have not yet found any good reason to set a fixed price for Nikki and the Robots Story Episodes, so we will prolong the pay-what-you-want campaign indefinitely for now, until we find a good reason to set a fixed price.

Nikki and the Robots Story Episodes will remain pay-what-you-want until at least 1st October, 24:00 GMT/UTC! Then we will make a decision on how to proceed. Our options include to stay in pay-what-you-want mode forever, to gradually increase the minimal price or to switch to a fixed price model.

Nikki Story Episodes Pay-What-You-Want Stats one week in

We made a bit more than EUR 2,300 so far, with about 450 purchases made. The average payment ranks at EUR 4.94. Many thanks to all our supporters!

We spent last week spreading the news about our release but also fixing some problems (a major Windows bug fix). Finally we sent free versions of Nikki and the Robots Story Episodes to our level contest winners and started using our Twitter account more actively.

Do you have suggestions or preferences on what pricing methodology we should follow? Or places, in which news about Nikki have not appeared yet, but probably should? If so, please get in touch via a comment below or email.

We're getting into the habit of releasing Windows-specific fixes! The following critical errors for Nikki and the Robots are now fixed. Windows users just have to update the game or re-download it.

core.exe could not load image file: C:\Documents and Settings\Администратор\Application Data\nikki-stroy-mode\data\png\tiles\black-blue\panel-standard.png

error: file not found: C:\Documents and Settings\Администратор\Desktop\nikki\core.exe

If you spot any bugs, please feel free to contact us or open a ticket on our bug tracker!

Nikki and the Robots Story Episodes are still pay-what-you-want and we'll prolong the campaign by one week (more on that later!).

We are proud to announce the release of "Nikki and the Robots Story Episodes".

Nikki and the Robots Story Episode 1 screenshots (more)

Join Nikki on a secret mission to fight the evil Dr. Lacroix. Test your skills in stunning platformer action and exciting puzzles — with the help of a variety of futuristic robots.

You can get the free part of the game (version 1.0) from our download page. For purchasing the Story Episodes visit:

buy.joyridelabs.de

For a limited amount of time the price for the Story Episodes will be pay what you want. So don't hesitate too long! And be generous: The Joyride Laboratories need money to produce further episodes. If you don't have a credit card or bank account, there are some alternative payment methods.

Nikki and the Robots Release Trailer (Story Episode 1)

If you like what we do, please spread the word! We also have prepared a press kit. (Thanks to Rami for presskit()!) Also available in German language.

tl;dr

• Nikki's Story Episodes are now available
• Buy them at buy.joyridelabs.de
• Spread the word!

Long time no post, so let's get straight to business! On Monday (17. Sep 2012) we will finally release the first story episode in pay-what-you-want mode! (this is kind of supposed to be a surprise, so don't tell anyone!) This will also mean a 1.0 release of the open nikki version with quite some fixes.

Also, tonight the first story episode will be playable during the Ate Bit Vomit Experimental Chiptunes party & exhibition. If you're in Berlin, Germany, hop on by!

Nikki had a recent shooting in which we picked screenshots to put on the buy page. Here are a few examples of shots that didn't make it:

Image: Open development graph: being open about your development makes noise, grows the community and lets you meet new people which has potential to interact which each other.

Today, Data Realms (Cortex Command) started sharing their backlog (aka ToDo-list) with the public. This made me want to re-capture some methods of being open about your game development and using this for marketing.

1. "Leak" alphas to pre-orderers

When your early version already has re-play value, allowing people to pre-order your games and to play your alpha versions is one of the best things you can do.

Image: Wolfire's Overgrowth alpha "leaks" get distributed via their preorder forum, which you can only see if you preordered the game.

2. Show off remaining tasks and bugs

Progress bars are beauty in players' eyes. Simply giving players read (and ideally write) access to your internal bug tracker allows super-fans to stalk you with no additional efforts on your side.

Image: Natural Selection 2's roadmap progress is being shared by Unknown Worlds live, directly on the game's homepage.

3. Share your design knowledge

When a game strongly depends on its plot, it often becomes hard for the writers and designers to let players read or play the story before the project is finished. Even in these cases there is still a lot available in the designers' heads that can be shared spoiler-free: Instead of letting the player experience an in-game plot-twist prematurely (before the game is released), you can teach them about how plot twists are constructed and examine examples of plot twists in existing games.

Image: Frictional Games shares thoughts about game and story design in their "Narrative not a game mechanic?" article.

Afterword

I myself work at Joyride Labs on a Linux/OSX/Windows game. Our engine code is open source, we sometimes share insights about our code (this is often Haskell-related and we should do this more often), our bug tracker is completely public, our pre-release versions (that exclude the story mode) are available for download for free.

This short article is based on old slides I used at a talk at HTW Berlin. Are there any other noteworthy examples you would like to share? Please do so in the comments.