Android sdk vs AndEngine vs libGDX

As the title says, soon I will begin to work on a game for android, so I decided to do a little test between Android SDK, AndEngine and libGDX. The results left me so amazed that I decided to put a video on youtube, hope you enjoy.

Joule Thief

Well ... it has been a whole month without a single post ^^ but this time it was for good reason, I was in school exams and they are going pretty good!

Now on-topic.

In these last days I've been thinking about many ways to save and produce electric energy. Almost none of the ideas resulted, but there is one that has worked wonderfully and that's what I've been talking about, it's called "Joule Thief".

According to wikipedia, joule thief is a term used to describe a self-oscillator energy booster, simple and low cost.

The peculiarity of this small circuit is to use almost all the energy of a battery cell, even after reaching that point that supposedly the battery is exhausted.

This is a possible electrical schematic, although there are many variations

And at the pictures of construction

For the coil, I used a metal core taken from a computer, the number of turns and the thickness of the wire was random.

Now the usefulness of this depends on our imagination, maybe light an LED with a single 1.5V cell, even use an old battery to recharge a Ni-Cd battery...

Good Joule Thief's :P

The internet status: SOPA

Hi, it makes a long time since I wrote anything. I hope you had a good new year, because I hadn’t...

Now on-topic, usually I’m not interested about news, I just don’t have patience, but in these last days I've been following some tweets, the central topic: SOPA and PIPA

But what is this?

Well…in Portuguese SOPA is soup and PIPA is barrel xD

According to wikipedia

“The Stop Online Piracy Act (SOPA) is a United States bill Introduced by U.S. Representative Lamar S. Smith (R-TX) to expand the Ability of U.S. law enforcement to fight online copyrighted Trafficking in counterfeit goods and intellectual property”

“The PROTECT IP Act (Preventing Real Online Threats to Economic Creativity and Theft of Intellectual Property Act, or PIPA) is to proposed law with the Stated goal of giving the U.S. government and copyright holders additional tools to curb access to "rogue websites dedicated to infringing or counterfeit goods "”

Using grep command

Let's talk about something used by some users of Linux that handle large amounts of information, the grep command.
This command lets you search for occurrences of text or expressions in a file or stdin, excellent links to search, numbers, IPs and other elements in large log files.

Quick way to encrypt your objects in Java

Hi, hope you have a good Christmas :) Mine was not bad, but here I am to write a little more.
Besides eating chocolates, these days I have continued some of my school works. One in specific is a game for android, that soon I will talk more in detail.

 
One important thing in games is the possibility of save the scores in a way that no one can forge, at least directly. So how do this in Java?

The simplest idea that I remembered was to put the scores in a particular class, make it serializable, apply a xor and write it to a file, to recover do the reverse process.

Choosing good passwords

My schoolwork is finally going well, so today I will take a break from works and everything related to programming.

Let's talk about something we use every day: passwords.

Even I who use computers for many years, sometimes I make mistakes. One of those led to one of my hotmail account to be hacked, and that happened precisely to the account that I use less and where I was using just two simple words found in the dictionary. Fortunately all ended well, but it isn't always the case ... so I prepared some tips that sometime we don't remember.

Tips to help you choose your Linux distribution

In the last three days I have been programming in android since I get up until I go to bed, so the last thing I want to see now is Java. For that reason I'll talk about another topic: Linux distributions.

As it happened to me, anyone who wants to move from Windows to Linux will face her first difficulty, choosing between a big number of distributions.

But what is a distribution?

Just like in windows family, you have Windows 9x, NT and CE, and for each of them, you have versions (as: 95,98,ME). In Linux it isn’t so different, with the particularity that the core (kernel) are the same.

So what’s the difference?

In Windows you have a company with total control over the core, applications and interface that the operating system will have, the final user may change something, but not as much as he may want.

In Linux anyone could grab the kernel, append a bunch of applications, tweak some parameters and puff, there’s a new distribution!

The freedom offered by Linux can look very good, but it isn’t always. This leads beginners to get confused and to have a fragmentation of the “help content”. Even worse is the fact that normally for the same thing there are at least two alternatives, both with their flaws and both have their qualities.

So I'll give some tips to help you choose one, and facilitate your entry into the magic of Linux