Learning Java from zero

Hello World,

Today I want to share some nice stuff to learn Java with you.

I found a very nice mobile application available online and for Android, IOS and Windows phone, I'm actually following the Java course and I found it very well explained, I recommend it for beginners, I use it when I'm on my way to go to work, I have 4h of train transportation per day so it allow me to spend this time efficiently :)
The application is separated in concepts divided in small subjects each subject into small paragraphs, you have to complete a little quiz at the end of each paragraph and a big quiz at the end of each concepts.
You can earn some badges and get a Solo Learn certificate for each course completed.

Here is the link: www.sololearn.com

I also purchased a book: Learn Java the Hard Way from Graham Mitchell which is really good book for making a first step to learn Java, I wish I had this one when I was studying.
It didn't talk about Object Oriented Programming but it cover the basis in a way that anyone can understand it. Each subject is separated in two: lesson + excercice.
The author statement is that many development books are quite hard to read from start to end for a beginer as they are not written for real beginners, so for him to write a book about learning a language you have to get the point of view of a real beginner and focus on simple things first and learn from zero, instead of going anywere using APIs...
I personnaly strongly agree with him and confirm his approach is a very good way to learn Java from the beginning.
For your information the author is actualy writing another book about Object Oriented Programming.

Here is the link: https://learnjavathehardway.org/

How to assign a variable with Sightly/HTL

Hello World,

I'm actually working as a Java JEE developper on Adobe Experience Manager, sometimes we build mockups to test our code using Sightly template language. As the documentation is not very clear about how to assign a variable I'll provide you a tip. To assign a variable with Sightly you have to use data-sly-test and not data-sly-use as below:

<sly data-sly-test.yourvariable="${yourvalue}"></sly>

Then you can call your variable value as below:

<textarea rows="4" cols="50" name="name">{"Myvariable":${yourvariable}</textarea>

You can also use your variable in a test:

<sly data-sly-test="${yourvalue==true}">displaysomething</sly>

I hope this can help a bit.

Licence

Hello world,

All the content of this blog is available under the following licence:


MonsieurZad de Zadwarf est mis à disposition selon les termes de la licence Creative Commons Attribution - Pas d’Utilisation Commerciale - Partage dans les Mêmes Conditions 4.0 International.
Fondé(e) sur une œuvre à http://monsieurzad.blogspot.fr/

Previews I

Hello all,

Here you can find some preview screenshots of the game:

Title screen:

Albatros ship mkI (bomber):

Gatling turret:

Stars Artifacts

Stars Artifacts grows in my mind a few years ago, it grows bigger and bigger and then after reading some books and articles about Java game programming I decided to make it real. So here we are.

Stars Artifacts will be first a simple old school shoot them up with some additionnal stuff added progressively, I want it to finally end as a multiplayer space ship simulation game, a kind of freelancer in 2d...

I don't know if I'll reach this goal and how long it'll take me to get a playable version but I'll try hard to work on it.

I'll free the source code once I judge the game ready for that.

This game will use slick 2d  ligdx with eclipse and some pixel art graphics.

Libgdx setup configuration with Eclipse - Part 5: Configuring Android SDK Tools

Once you've installed the Android SDK Tools you'll be able to launch the Android SDK Manager

Here it is.

Launch it and you'll get a wonderfull scary application in front of you:

Omagad! What the fuck is that ?! o_O

If you don't know what you are supposed to do with it:

As every hitchickers knows...
credit: https://teenskepchick.org/2012/05/25/dont-panic-unless-youve-forgotten-your-towel/

You can go to the following link:

http://developer.android.com/about/dashboards/index.html

Were you'll get usefull information about Android terminal used worldwide sucha as Android version distribution, open GL version distribution...

We will use the Platform Versions information to configure our Android SDK Manager, in the screenshot below you can see percentage of Android version used with related API:

You have to choose your API depending on number of people you want to reach or functionnalities you will use. Please check this post for quick configuration: http://stackoverflow.com/questions/26535897/which-android-api-to-use-in-libgdx-android-sdk-manager

Here is what I use for example:

Libgdx setup configuration with Eclipse - Part 3: Android SDK Tools

Now you have to download the Android SDK Tools:

1) Super fast shortcut
If you want to download directly what you need go here:
https://developer.android.com/sdk/index.html#Other

2) Shortcut

There is a shorter path if you click on Other Download Options so you get directly to the download you need:

3) The (too) long way

- Go to the link below if you want to spend time by clicking useless links:
https://developer.android.com/sdk/index.html

- Click on Installing the SDK, as we didn't need Android Studio (>1Go download... -_-') we will just download the stand alone SDK (136Mo download  yeah! \o/)

- So click on Stand alone SDK Tools:


Go to Part 4: Libgdx setup configuration with Eclipse - Part 4: Android SDK Tools

Libgdx setup configuration with Eclipse - Part 4: Android SDK Tools

- You'll get a new page of blahblahblah stand alone sdk tools only includes the sdk tools (thanks captain obvious...), click on download the SDK now ("and stop bother me with your 1Go download :D")

- Once you click on this link you'll go to a new page already focused on the bloody android studio bundle package...

 

Ah bastard...

 Scroll up and you'll find what you need:

- So now download the one you need and install it (again with default option it works perfectly) it will normally open the SDK Manager if not you can find it on your computer at: C:\Users\YourUser\AppData\Local\Android\android-sdk, assuming you install the SDK Tools with default options and YourUser is your user name in Windows

Libgdx setup configuration with Eclipse - Part 1: introduction & my hardware/software configuration

Hello world,

[LAST UPDATE 19/10/2016]

Today I'll give you my configuration setup for Libgdx with Eclipse, this will update some stuff visible on the book Learning Libgdx Game Development (first edition) from PacktPub. As Libgdx and software updates regularly I'll provide you my hardware and software from the time I setup my Libgdx development environment on Eclipse. Everything here maybe not usefull, some things probably have to be modified and/or optimized...

My hardware and software configuration is:

    - Surface Pro 2 (i5-4300U CPU, 4 Go ram)
    - Windows 10
    - Mozilla Firefox v49.0.1
    - Eclipse version: Neon.1 Release (4.6.1)
      Build id: 20160913-0900
  
    - Java version returned from command line:
    java -version
    java version "1.8.0_92"
    Java(TM) SE Runtime Environment (build 1.8.0_92-b14)
    Java HotSpot(TM) 64-Bit Server VM (build 25.92-b14, mixed mode)
  
    - Android SDK Tools v1.16 with following API installed:
    Android 6.0 (API 23)
      Android M (API 22, MNC preview)
      Android 5.1.1 (API 22)
      Android 5.0.1 (API 21)
      Android 4.4W.2 (API 20)
      Android 4.4.2 (API 19)
      Android 2.2 (API 8)

      Android SDK Tools Rev. 24.3.4
    
      Android SDK Platform-tools Rev. 23.0.1
    
      Android SDK Build-tools Rev. 20

That's all for the hardware/software part.

Before anything it is recommended to create a folder on your computer where you'll put everything you need so that you have everything at you fingertips.

What you need:
- Eclipse (Part 2)
- JRE & JDK (Part 2)
- Configure variables (Part 2)
- Android SDK Tools (Part 3 & Part 4)
- Eventually a GitHub account if you want to share your code.

Go to Part 2: Libgdx setup configuration with Eclipse - Part 2: Eclipse, JRE, JDK and variables

Libgdx setup configuration with Eclipse - Part 2: Eclipse, JRE, JDK and variables

[LAST UPDATE 19/10/2016]

First you have to download Eclipse here, I use the Luna version as some plugins are not implemented for Eclipse Mars yet, no installation is required for Eclipse just put it where you want:
https://eclipse.org/downloads/eclipse-packages/

Get JRE and JDK here from the time I'm writing (19/10/2016) JRE and JDK version 8u112:

JRE: http://www.oracle.com/technetwork/java/javase/downloads/jre8-downloads-2133155.html

JDK: http://www.oracle.com/technetwork/java/javase/downloads/jdk8-downloads-2133151.html
Once you get both JRE and JDK install them with default parameters.

Now you have to configure you variables, on windows:

- Right click on "This Computer" on the Windows explorer then go to properties:

- Then click on Advanced System Parameters as visible in the screenshot below:

- Then click on Environment variables as visible in the screenshot below:

- Now you have to configure two variables JAVA_HOME and PATH, click on new button on the User Variables part:

- Then fill up the form as below assuming your JDK is installed on C:\Program Files\Java\jdk1.8.0_60

Go to part 3: Libgdx setup configuration with Eclipse - Part 3: Android SDK Tools

Libgdx issue with RGB color not appearing correctly (glClearColor)

Hello world,

Today i'll give you a tip I found while I searching on the internet about an issue related to RGB color not displayed correctly in Libdgx.

I was searching for a nice blue background for sky in Piou with GraphicsGale and get the RGB code for it:

 So in my Java code I wrote:

Gdx.gl.glClearColor(0, 187, 249, 0);

but when I launched the game the color appears as an eye bleeding cyan:

 

Aaaaargh Y_Y it burns my eyes !!!!

So I searched why the blue didn't appears as it must be and I've found an answer on Stackoverflow so I modified my code with:

Gdx.gl.glClearColor(0/255f, 187/255f, 249/255f, 0);

And finally get the blue sky correctly displayed:

Fiuuuu, it's faaaaaar better :)

Hope this will help some people arround here.

How to connect Eclipse with GitHub

Hello world,

I tried to learn how to connect Eclipse with GitHub and i found some usefull ressources:

Pro Git book by Scott Chacon and Ben Straub available for free.

Tutorial explaining how to configure Eclipse and Egit (in french) by Larent Guérin.

Another tutorial explaining how to connect Eclipse with GitHub (in french) by Benjamin Besse.

And it works now \o/ !!!
 

[UPDATE FROM 20/10/2016]  

I encountered some issues when trying to make Eclipse Neon and GitHub working together. After getting multiple error messages I found the solution:

Install EGit and Mylyn plugins

Go to Help -> Install New Software

With your internet browser, you have to go to the link provided here :

http://www.eclipse.org/egit/download/

You have to install EGit plugin :

http://download.eclipse.org/egit/updates

and then Mylyn connector plugin :

http://download.eclipse.org/egit/github/updates

You can encounter errors while trying to push your code, connection errors and so on like this one:

if it happen go to Help -> Install New Software again and use the following link as indicated in the message:

http://download.eclipse.org/mcp/neon

Select all the updates.

Once they are installed Eclipse will work correctly with GitHub now

Indie game development

Hello world,

Today i'll write about indie game development, in the past game development was the apanage of very clever people (called geeks and sadly underestimated...) which had to work with very limited ressource due to hardware specifications (Comodore, Atari...). This equipment was expensive and difficult to operate as IT was in its infancy.

Blablabla... i'll not provide you a course about IT history uh...

Nowadays IT has been democratized (at least in Industiralized countries) and with IT, internet. Sharing knowledge never been so easy and fast, communities grow up, new languages appear...

Languages evolve with the community and some projects were created, frameworks were born, created from developers for developers. Now non IT people can make games, tutorials are shared all accross the internet... But making a game still needs mathematics (argh!) and physics (re-argh!) knowledge.

Do you remember the days you were at school in mathematics course "Hell! i didn't understand a bunch of these things >< ! and what is it used for ?! We will never use it in our profesionnal career!"

Unfortunately for you (me of course as i'm really bad in mathematics -_-') all (or at least most of) the universe works with mathematics (NOOOOOOOO!!! °o°).

As i didn't get much far in my studies (bac +2 in Fance: technical degree in application development) i didn't have any notion in physics and my knowledge in mathematics is weak. It's particularly a handicap in game development, and development in general, as it is supposed to require analytic and logical brain.

But, even you don't like mathematics and you're not good at it, you can make games, because your strenght are elsewhere. You can have good imagination, you can be good in graphics, you can see things with a new look...

Of course mathematics are important for development and most of all in game development, but it does not have to be a drag in you project.

There are many good tutorials on the internet, with patience, work and will you can do what you want.

So, if you feel you'll not make it, don't give up, let your big project rest for a while and keep working on a smaller and easier one, you'll get more confidence with it.

If i found easy way to explain mathematics or physics rules i'll use in my games i'll post it as i think knowledge must be shared to make things better.

Books i'm reading about Libgdx

Hello world,

Today i'll show you some books i read to learn Libgdx game development

Learning Libgdx Game Development by Andreas Oehlke is the first book i bought about Libgdx. the book is really clear to understand and allow us create a platform game step by step. The code is correctly explained and accompanied by illustrations. There is a second edition of this book i didn't read yet. The publisher Packt Publishing allow us to get the physical or digital version of the book or both, which is really nice as we sometimes cannot carry physical books for practical reason.

LibGDX Game Development Essentials by Juwal Bose is a step by step book to make a flappy bird clone game with additionnal stuff. I didn't fully read it yet but from what i saw the book explain many way how to create a Libgdx project. The quality is same to Learning Libgdx Game Development book.

Libgdx Cross-platform Game Development Cookbook by David Saltares Márquez and Alberto Cejas Sánchez contains code recipes with illustrated examples. I didn't read it yet but it looks very interesting as it covers many aspect of Libgdx and game development (2D sound system, Box2D...).

Also you can find many ressources online about Libgdx here is some usefull links:

https://github.com/libgdx/libgdx/wiki the official Libgdx wiki

http://steigert.blogspot.fr/ (in english) a blog with Libgdx tutorials
http://tutoriel-libgdx-android.blogspot.fr/ (in french) a blog with Libgdx tutorials
http://obviam.net/ (in english) a blog with Libgdx tutorial
http://www.creationjeuxjava.fr/home (in french) Libgdx video tutorials
https://anthdeldeveloper.wordpress.com (in english) a game developper blog with an asteroid game tutorial
http://www.codeproject.com/Articles/702957/Create-your-first-Android-Game-with-libgdx complete example of simple game made with Libgdx
http://www.java-gaming.org/ (in english) a great community of Java game developpers
http://www.b4x.com/ (in english) forum post introducing to Libgdx
http://stackoverflow.com/ usefull website based on question/answer system
http://dmentrard.free.fr/ mathematics and physics notion explained with animations
http://opengameart.org/ free graphics to use with your game