This document summarizes Milan Dinic's presentation on developing Android games using the libgdx framework. It discusses using the Wreck-It Ralph and Giana Sisters games as inspiration and covers choosing libgdx as the framework due to its support for multiple platforms, open source nature, and ease of setup. It provides an overview of the libgdx API and covers sprite creation, sound effects, physics implementation, debugging, and publishing a game to Google Play.

1. Title
presenters
Android game
development
Milan Dinic
@milandinic

2. Idea

3. Idea
Wreck-it Ralph movie - Fix it Felix game

4. ● Most of the graphics can be found online
● Some of the music can be found online
● No exact game play, but I could imagine
● Copyright by Disney
● Exists for IOS
About Wreck-it Ralph

5. Idea
The Great Giana Sisters - Commodore 64 version

6. About Giana Sisters
● Most of the graphics can be found online
● Some of the music can be found online
● Game play, remember most of it, YouTube videos
● Copyright by Rainbow Arts, developed by Time Warp
Productions
● Exists with all new look on Google Play

7. Giana Sisters on Google Play - Paid

8. Giana Byte (8-bit) - Free

9. Set Goals - Milestones
1. Minimal presentable/playable
2. Google store
3. More features with versions

10. Choose your framework

11. Choose your framework
● Free
● Multi-platform
● Opensource
● Familiar language

12. No framework at all

13. No framework at all

14. Project Anarchy
● http://www.projectanarchy.com
● Recommended by many
● C++
● Free
● Multi-platform

15. Project Anarchy
● http://www.projectanarchy.com
● Recommended by many
● C++
● Free
● Multi-platform
● No examples
● Complex setup
● Closed source

16. libgdx
● http://libgdx.badlogicgames.com/
● Found by accident
● Java
● Free
● Multi-platform

17. libgdx
● http://libgdx.badlogicgames.com/
● Found by accident
● Java
● Free
● Multi-platform
● Working examples
● One jar setup
● Source on GitHub

18. Development
● Tools: Eclipse/AndroidStudio, GIMP
● Stack: Gradle, Libgdx
● Libgdx: State Machines, Behaviors

19. Libgdx
One framework to rule them all
● Android
● iOS
● Desktop / Jar
● HTML5

20. Libgdx - Projects
Gradle generates projects for us:

21. Libgdx - API crash course
● com.badlogic.gdx.Game
● com.badlogic.gdx.Screen
● com.badlogic.gdx.math.Vector2
● com.badlogic.gdx.math.Rectangle
● Gdx.files.internal

22. Libgdx - API crash course
● com.badlogic.gdx.audio.Sound
● com.badlogic.gdx.audio.Music

23. Libgdx - API crash course
● com.badlogic.gdx.graphics.Texture
● com.badlogic.gdx.graphics.g2d.TextureRegion
● com.badlogic.gdx.graphics.g2d.Animation

24. Libgdx - API crash course
public interface Screen {
public void render (float delta);
…..........
}

25. Libgdx – Memory management
Most of resources are not managed by the Java garbage collector, but by native drivers
public interface Disposable {
/** Releases all resources of this object. */
public void dispose ();
}

26. Libgdx – Camera
com.badlogic.gdx.graphics.g2d.SpriteBatch
OrthographicCamera cam = new OrthographicCamera(20, 16);
batch.setProjectionMatrix(cam.combined);
batch.begin();
batch.draw(...);
batch.end();
cam.position

27. Gravity and physics

28. Gravity and physics
Don't reinvent the wheel - a lot of them online

29. Debugging
● On hardware: adb install -r gianabyte.apk
● On desktop

30. Sounds

31. Sounds - Sfx generator
http://www.bfxr.net/

32. Sprite

33. Giana Sisters Sprites

34. Sprite tools
● ImageMagick
● GIMP

35. imagemagick
sudo apt-get install imagemagick
convert input.gif -coalesce -repage 0x0 -crop 24X20+138+100
+repage output.gif
montage output.gif -tile x1 -geometry '1x1+0+0<' -alpha On
-background "rgba(0,0,0,0.0)" -quality 100 output2.png

36. imagemagick
sudo apt-get install imagemagick
convert input.gif -coalesce -repage 0x0 -crop 24X20+138+100
+repage output.gif
montage output.gif -tile x1 -geometry '1x1+0+0<' -alpha On
-background "rgba(0,0,0,0.0)" -quality 100 output2.png

37. imagemagick
sudo apt-get install imagemagick
convert input.gif -coalesce -repage 0x0 -crop 24X20+138+100
+repage output.gif
montage output.gif -tile x1 -geometry '1x1+0+0<' -alpha On
-background "rgba(0,0,0,0.0)" -quality 100 output2.png

38. GIMP tricks
•
Replace a color with another
•
Difference on images

39. Intro Level

40. Intro Level

41. Launcher Icon
Courtesy of GIMP

42. Launcher Icon

43. Launcher Icon
more at http://goo.gl/4umtAK

44. Use the Inkscape
Daniel Egan: Creating Your First 2D Game in GameMaker http://goo.gl/3u8KIS

45. Use the Inkscape

46. Use the Inkscape

47. Highscores
● Online – Parse.com / Firebase.com
● Local when no Internet is available – SharedPreference

48. Signing the application
1. Generate key (keytool -genkey -v -keystore giana-key.keystore -alias giana -keyalg RSA -keysize 2048
-validity 10000)
2. Compile your application in release mode
3. Sign (jarsigner -verbose -sigalg SHA1withRSA -digestalg SHA1 -keystore giana-key.keystore android-release-unsigned.apk giana)
4. Verify signature (jarsigner -verify -verbose -certs android-release-unsigned.apk)
5. Align (zipalign -v 4 android-release-unsigned.apk gianabyte.apk)
more at:
http://developer.android.com/tools/publishing/app-signing.html

49. Testing

50. Testing
On device is a must!
● jUnit
● Exploratory

51. Numbers after one month
● 15 levels + intro
● 7 monsters
● 2 static dangers (water and spikes)
Totals downloads > 1.7K

52. Numbers after 6 months
● 31 levels + intro
● 12 monsters plus boss
● 2 static dangers (water and spikes)
Totals downloads > 12K

53. Calendar

54. Calendar

55. Marketing
● social networks
● adds
● reviews

56. Try it on Google Play
Can be found by name: ‘Giana Byte’ or ‘Giana’
Or by QR Code
Have fun :)

57. Q & A