Category Archives: Games development

Libgdx for Cross-platform Game Development Cookbook is out!

libgdx cross platform development cookbook

After over a year of long hours after my day job, sweat, blood and tears, my colleague Alberto Cejas and I are extremely proud to announce that our Libgdx for Cross-platform Game Development Cookbook has finally been published.

The cookbook has over 75 practical recipes on how to get stuff done with Libgdx. It covers pretty much everything: graphics, input, audio, physics, maps, deployment and third-party extensions among many, many more. Far from being a dumbed down guide, it offers content ranging from basic to advanced. A good chunk of it you won’t find anywhere else.

Conveniently, you can get a DRM free e-book copy or go for the physical edition, which also includes the digital one. Additionally, you can get physical copies from Amazon. All the source code can be downloaded from both the publisher’s website and our GitHub repository. We’ll do out best to maintain the later so it works flawlessly with the latest Libgdx version.

It’s been a hell of a ride with plenty of ups and downs. We are happy with the result, have high hopes on the project’s success and are eager to get some feedback from readers.

Many thanks to those of you who have shown interest in the project and even pre-ordered it. The response has been really positive!

Also, thanks to all our technical reviewers, you greatly helped improved the final result with your feedback.

Lastly, special thanks to Mario and the Libgdx team for fostering the best open source game development framework and community. Needless to say, this book wouldn’t exist without them.

Happy coding!

Ashley 1.3.1 released


Small stability release for Ashley entity framework this time.

Bug fix: fixed IllegalArgumentException thrown when trying to remove components from an already reset entity. The call has no effect now. Thanks for that SgtCoDFish.
Bug fix: fixed family match failure due to silly silly hashing.
Bug fix: fixed entity.getId() always returning 0 for recycled pooled entities.
Bug fix: fixed nested iteration problem caused by adding/removing entities from an entity added/removed listener handler.
Bug fix: fixed missing type error in GWT when using PooledEngine. GWT should be quite smooth now.

The new nightly dependency is com.badlogicgames.gdx:ashley:1.3.2-SNAPSHOT.

Big thanks to everyone who reported issues and especially to those who also contributed with PRs. Keep it up!

Ashley 1.3.0 released


Time for another Ashley entity framework release! This time, the focus has been on stability by getting rid of as many bugs as we could find. Check all the new goodies below.

  • API addition: adds IntervalSystem and IntervalIteratingSystem, which are updated at a fixed interval.
  • API addition: adds getEntities() to IteratingSystem and IntervalIteratingSystem.
  • API change: entities use long as ID. Changes entity.getIndex() for entity.getId(). Ids are reset to 0 after the entity is removed from the engine.
  • Bug fix: we finally got rid of the issues related to deleting entities and adding/removing components mid system processing.
  • Bug fix: fixes problem with removing pooled entities.
  • Bug fix: fixes pooled entities not being fully reset.
  • Bug fix: fixes broken GWT compatibility.

The new nightly dependency is com.badlogicgames.gdx:ashley:1.3.1-SNAPSHOT.

As usual, open a new issue if you find anything that’s not working properly and feel free to submit a pull request!

Libgdx Cookbook Git repository evolution

As I have mentioned before, I have been working on a book titled Libgdx Cross-platform Game Development Cookbook, which is set to be released next month.

Me and my co-author Alberto used a Git repository throughout the text and sample code development process. Using Gource, I have created a video that illustrates the repository’s evolution. Neat, isn’t it?

For those interested, here are the options I used.

gource -1280x720 --seconds-per-day 0.5 --auto-skip-seconds 0.5 --key

Ashley 1.2.0 released


There have been quite a few things happening in Ashley during the past month, enough to call for a brand new release. Ashley 1.2.0 can now be fetched from Maven Central and this is what you’ll find new.

  • API addition: people requested to put Entity#getComponent(Class) back in, so we accepted SgtCODFish‘s PR. ComponentMapper is still the most efficient and encouraged method to retrieve an entity’s components.
  • API addition: added PooledEngine#clearPools() to delete unused entity and component pool memory.
  • API addition: adds EntitySystem#setProcessing(boolean) so as to be able to enable/disable systems at will.
  • API addition: adds Engine#getSystems().
  • API addition: you can now listen to entity events on a per family basis.
  • Crash fix: things would blow up if you deleted entities from IteratingSystem#processEntity().
  • Bug fix: removing listeners while dispatching a Signal would make other listeners miss the event. Thanks to vlaaad for the PR!
  • Bug fix: some entities were skipped if the user removed an entity from the engine mid system update. Removing an entity from a system by changing its components mid iteration also caused problems, which are now solved.
  • Bug fix: there was a problem with family membership not being properly updated when removing a component from an entity was supposed to result in said entity being added to the family. This only affected families that exclude components.
  • Internals: small performance improvement.
  • Others: added benchmark suite to compare Ashley’s performance with Atermis’.

If you’re using the nightly builds, please change your dependency to com.badlogicgames.ashley:ashley:1.2.1-SNAPSHOT. Both the wiki and the javadocs have been updated to reflect the latest changes.

Thanks to everyone using Ashley, opening issues and, of course, sending pull requests. I’m extremely pleased with the response, it’s awesome to see how active things are.

Keep it up guys!