It’s interesting to see how Western Europe is the region with a greater quota of free (and probably open source) tools, followed by Latin America, and on the completely other end there is US/Canada. For sure it can be related to the culture of these countries, and therefore to the economic systems.

The tips of this post are only applicable to Lithium-ion batteries.

PowerTOP

The easiest and faster way of improving the power efficiency of the laptop, is at software level. With the PowerTOP application we can not only monitor which software is responsible of our CPU cycles and hard disk spinning, but also  (and more important) tune several parameters related with the energy. For example, enable the auto-suspend of an external USB device when not in use, or an energy saving feature of the wireless card.

That’s the PowerTOP tunables section on my laptop, with some settings not optimized.

After playing with it, you will probably notice that the settings are not saved, and after rebooting you have to run PowerTOP and set everything again. Solution: if you run PowerTOP with the –html option, it will generate an HTML (surprise!) report with all the command line instructions to set each tunable. So, then you only have to add these commands to an init script (for example, /etc/rc.local on Arch Linux), and you’re done!

Just a last tip: do not enable autosuspend for an external mouse… it’s really annoying.

Charging cycle

If you are like me and usually run your laptop connected to AC, your battery it’s probably almost always charged at 100%. This is not good. But but be optimal, is having it charged at max of ~85%, and then let it discharge by its own until it reaches ~35%.  About “telling” you laptop to follow this charging cycle, I only know how to do it with Thinkpads, which is setting:

echo 40 > /sys/devices/platform/smapi/BAT0/start_charge_thresh
echo 80 > /sys/devices/platform/smapi/BAT0/stop_charge_thresh

having Tp smapi installed. Details about how to implement it on a script can be found on the ArchWiki.

Actually, the best way of keeping a battery in an optimum state, when not in use, is having it at 40% of it’s charge and storing it on the fridge. If you try that, please put it on a sealed plastic bag, with some rice to absorb humidity!

Para volver a avivar estas temáticas, nada mejor que hacer publicidad de un sorteo de miniaturas. Vale, no es de forma desinteresada porque al hacerlo tengo más posibilidades de ganar, pero no les voy a hacer ese feo :P.

A lo que iba: el blog sobre miniaturas Dragones y Castillos, para celebrar que cumplen dos años, han montado un sorteo más que digno para sus seguidores. Participar es facilísimo, pudiendo hacerlo simplemente dejando un comentario en la web o siguiéndolos en twitter. ¿Y los premios? Fuá los premios. Una miniatura del Asesino de Shadowcrafter pintada por Iguazzu (que bien quedaría en mi estantería). Otro: una caja Starter Pack del juego Némesis de Zenit Miniatures. Y, por si fuera poco, un manual y una miniatura de Carnevale de Vesper-on Games. Tres premios, tres posibilidades de llevarse algo.

¿Aún estás leyendo este post? :)

Aunque me habría gustado que lo hubiera hecho con Gimp, la herramienta que ha usado es el Adobe Photoshop CS2. Aún así, él mismo asegura que es posible encontrar funcionalidades equivalentes en Gimp. Bueno, después de este breve ¿prólogo?, os dejo con el tutorial en cuestión:

1. Creamos un nuevo archivo con fondo transparente. El tamaño que yo he utilizado es de 450×450 pixeles. Luego, rellenamos de negro y con la opción de “Marco Elíptico” hacemos una circunferencia perfecta:

2. Sin deseleccionar, nos vamos a Filtro > Interpretar > Nubes y después Filtro > Interpretar > Nubes de Diferencia:

Una vez en este paso, lo siguiente que tenemos que hacer es presionar CTRL+I para invertir los colores.

3. Obtendremos como una circunferencia de nubes blancas. El siguiente paso será abrir la ventana de Ajuste (CTRL+L) y moveremos el cursor gris hasta que tan sólo nos queden los “rayos”:

4. Ahora, deberíamos ir a Filtro > Estilizar > Hallar Bordes. Y la imagen debería quedarnos así:

5. He de comentar que la imagen de arriba no se corresponde con los pasos anteriores sino de otra capa posterior, pero bueno, se ve el efecto.

Ahora comenzaremos a “colorear” nuestra “tormenta”. Presionamos CTRL+U y marcamos la opción de colorear y le damos la tonalidad de la cuál deseemos crear nuestra estrella. Lo “normal” es utilizar una escala de rojos a amarillos, pero también hay estrellas de cuyo espectro las hace blancas, azules e incluso verdes. En este ejemplo, empiezo por el color rojo intenso:

6. Duplicamos la capa y le damos otra tonalidad para después fusionarla con la primera. En este caso, elegí un amarillo intenso:

7. El “truco”, consiste ahora en fusionar las dos capas con una “sobreexposición lineal” en la primera de las dos capas:

Tras lo cual, debería quedarnos algo así:

8. Ahora, debemos tan solo combinar las dos capas y ya tendremos “una parte” de nuestra estrella. Ahora, resta la parte más pesada; que consiste en repetir los pasos anteriores tantas veces como veamos necesario hasta crear una imagen más parecida a una estrella.

Hay que pensar que cada paso podemos jugar con las “tonalidades” e incluso las fusiones entre capas. Generalmente se utilizará la sobreexposición lineal, pero puedes crear capas con “sobreexposición del color”, o “superposición”… según vayamos viendo. También pensaremos en como jugar con las capas para crear una “esfera ardiente” más creíble.

Yo tras unas cuantas capas he obtenido esto:

Tiene un color más parecido a una “llamarada” o una “Tormenta de Fuego” con los contrastes de color si lo comparamos con la estrella que puse de ejemplo. Esto es debido a “los tonos medios” cuando se realizan los ajustes en el paso 3. Para ello, podemos modificar en las Opciones, las tonalidades de luz, medios y sombras para crear en vez de un fondo negro con rayos, una imagen menos contrastada. De esta forma, podemos añadir capas que cubran mejor la superficie en vez de tener sólo 4, 5 ó 6 “tormentas” que se entremezclan pero siempre con un “fondo negro”.

Comento esto, porque es algo que de lo que me di cuenta para tener una estrella que parezca densa sin parecer necesariamente una llamarada.

9. Cuando estemos satisfechos con nuestra estrella comienza la segunda parte del trabajo, que consistirá en crear la “corona solar”. Para ello duplicamos la capa de nuestra estrella y en la capa inferior aplicamos los efectos de “resplandor exterior”:

Y con los siguiente parámetros; que podréis modificar a vuestro antojo. Lo único, que tendréis que tener en cuenta que las capas más abajo tendrán que tener siempre una extensión menor:

10. Ahora, procederemos a hacer lo mismo en la capa superior. En realidad podríamos tener muchas más capas y crear un halo mucho más complejo… pero eso ya es cuestión de ir probando y hacer lo mismo. Lo único que tendremos que tener en cuenta es que las capas siguientes deberían ser más extensas y con un tono “menos luminoso”. Si para la primera capa, yo elegí un amarillo, para esta segunda… he elegido una tonalidad rojiza:

11. Deberíamos tener esta imagen o algo parecido:

Si observáis, el contorno del astro está un poco pixelado y “queda feo”. Bueno, un truquillo que he utilizado yo es en la capa superior añadir un efecto de “resplandor interior”, así sin más:

Y nos quedaría algo así:

Ahora ya está mucho mejor definido .

12. Bueno, seguimos con nuestro trabajo para la corona solar. Ahora creamos una nueva capa y la rellenamos de negro (o simplemente la capa inicial la duplicamos, vaya). Ahora deberíamos irnos a Filtro > Interpretar > Nubes y después Filtro > Interpretar > Nubes de Diferencia. Para repetir este último filtro pulsamos unas siete veces CTRL+F. ¿Por qué siete? Bueno, pues no lo sé, porque no lo he probado ni con más ni con menos, pero en el tutorial que leí venía así. Así que si queréis podéis investigar si hacen falta más o hacen falta menos .

13. En este momento mientras está seleccionada está última capa deberíamos pulsar la tecla de CTRL y hacer clic justo en “la miniatura” de la capa de nuestra estrella (da igual cual). De esta forma lo único que obtendremos será una selección del contorno de la capa.

Ahora sólo resta pulsar suprimir y deseleccionar, y ya lo tenemos:

En estas imágenes se ve en negro la capa. Eso es porque no había aplicado antes el filtro de nubes. En la siguiente imagen se ve como quedaría realmente:

14. Por último, añadimos la opción de fusión que nos dará el resultado que estábamos buscando. Para ello, utilizaremos la “sobreexposición de color” y nos quedará algo tal que así:

15. Y hete aquí nuestro astro rey de cualquier punto de la galaxia. Pero vaya… no se le ve muy esférico, ¿verdad? Pues nada, para eso sólo necesitamos volver a obtener el contorno de la estrella como he comentado antes y nos vamos a Filtro > Distorsionar > Esferizar. Y lo haremos en modo “normal” y con un 100%. Con ello, ya tendremos nuestra estrella completamente terminada:

Añadido extra:

Personalmente remarcaría un par de cosas en el tutorial. Como por ejemplo:

- Los “tonos medios”, con capas como estas:

- En “esferizar cada capa” en vez de hacerlo al final. De esta forma queda, en mi opinión, mucho mejor definida la estrella.

- Y sobretodo, en “ir jugando” con distintas opciones de fusión para ir creando la estrella.

Alternative to Google Search

There is not much to explain here, as I’ve dedicated a whole post to this topic. The more I use Duck Duck Go, the happier I am with it. Particularly because it is quite easy to change between a world wide search or a local (country) search. I use the former for general queries like programming issues, info about books, etc., and the other when looking for restaurants, leisure activities, etc.

Alternative to Google Maps

This one is a bit tricky. I have to admit that Google Maps offers better search capabilities than its main competitors: Open Street Map, Yahoo! Maps, and Bing Maps. You can misspell the name of a business or just provide some keywords, and it will try to find the best match.

But (there is usually a but), I like quite much the “art” of Open Street Map, because it reminds me paper maps and some bonuses like detailing the exact position of the underground entrances (which Google doesn’t, just the approximate location of the station). So, sometimes I use one, and sometimes the other.

Alternative to Gmail

There was not much sense on switching to Hotmail, Yahoo or any other company if privacy was an issue. More or less they all share the same practices. So, the best solution was having my own mail server. I have a modest VPS on Linode, so I set-up the server as you can see on this guide. Therefore, I have an IMAP server which I can use with Thunderbird or when in roaming with the nice Roundcube webmail.

The only lacking functionality is server-side filtering, which I still have to set-up (if you know a way to extend a day to more than 24 hours, please tell me!). I could live with client-side filtering on Thunderbird, but I also want to enjoy it when using the webmail interface.

Alternative to Google Calendar

Having already a mail server, why do not have a calendar server? I took the same approach, and set-up a calendar server using CalendarServer which I can sync with Thunderbird and my iPhone. For even more functionality, I added a web interface with AgenDAV. This time, there is not any feature missing.

Alternative to Google Reader

I wanted to use my feed aggregator on several computers, so setting up a desktop client on each one and trying to get all of them synced was not a viable option. Therefore, I opted for an in-the-cloud solution with a web interface, as Google Reader is. And again, my server comes to rescue! I liked what I saw on Tiny Tiny RSS webpage, I installed it, and I’m very happy with how if works. Nothing to be jealous from Google Reader. It even have a mobile-optimized interface, so it’s not a hassle to check it from the phone.

Alternative to Picasa

To make it clear, I didn’t check the terms of service of Flickr and other providers. I suppose they’re good enough because they’re used by several artists, but I decided to choose the hard way: build my own web gallery. I found Piwigo, with all the features I was looking for and with enough eye-candy to please me. So, after one afternoon of work, I had it working on my server.

Conclusions

I realize that all the options I’m using are not an option for everybody, because of the simple fact that you need your own server and set it up. This simplify the issue to your priorities. If you want privacy and company-independence, learn how to do it or pay somebody to do it for you. If you don’t care, you can just keep using the free services.

Up to now, and after a heavy use of it, I’m very happy with the decision I’ve taken. It has also been useful to learn some new things, and as learning is fun, it has been a nice leisure activity. Mmm, maybe they’re right when they call me geek :P

Installation

The packages I installed were:

gamin postfix postfix-mysql courier-imap courier-imap-ssl libsasl2-2 libsasl2-modules php-auth-sasl sasl2-bin libpam-mysql

I think that these are enough (with its dependences) to get a working system. I’m not 100% sure because I documented this part a posteriori, after playing a bit around installing/uninstalling things.

Configuration

Postfix

On /etc/postfix/master.cf I used:

submission inet n - - - - smtpd
 -o smtpd_tls_security_level=encrypt
 -o smtpd_sasl_auth_enable=yes
 -o smtpd_client_restrictions=permit_sasl_authenticated,reject
 -o milter_macro_daemon_name=ORIGINATING

The file /etc/postfix/transport did not exist, so before

postmap /etc/postfix/transport

I did

touch /etc/postfix/transport

Courier

All the references to

/etc/authlib/

and

/etc/courier-imap/

must be changed to

/etc/courier/

On /etc/courier/authdaemonrc, instead of

MYSQL_MAILDIR_FIELD maildir

we must use

MYSQL_MAILDIR_FIELD     concat('/home/vmail/',maildir)

Cyrus

Instead of editing /etc/conf.d/saslauthd we have to edit /etc/default/saslauthd to say:

START=yes
MECHANISMS="pam"
OPTIONS="-c -m /var/spool/postfix/var/run/saslauthd -r"

Instead of /usr/lib/sasl2/smtpd.conf we have to edit /etc/postfix/sasl/smtpd.conf to:

pwcheck_method: saslauthd
 mech_list: plain login
 saslauthd_path: /var/run/saslauthd/mux
 log_level: 7

Rouncube

To make the directories writable to the server, we have to use:

chown -R www-admin:www-admin temp logs

rc.conf

There is no rc.conf to control boot services on Debian. All the services installed on this guide are automatically startup at bootup, so nothing to do here.

The end

And that’s all. With that we should have a working mail server, using MySQL to store user’s info, mail storage on the filesystem, PostfixAdmin to manage accounts and aliases and a nice webmail with Roundcube.

I remember that I did it with Gimp, following a tutorial about how to do a 3D cube. I even used the same colours and did everything exactly as explained there, so it was not very original… but I liked it. Geez, so many years have passed since then…

The old cube

This time, I tried asking my brother (who is supposedly studying graphic design or something like that :P) for help, but after a few weeks he has not shown much interest on it. So, “ni corto ni perezoso”, one afternoon of boringness I opened Inkscape and started to play with it. The results are what you can see below.

The new cube?

So, what do you think? Actually, I’m open to new options, therefore if you think you can do something much better and appealing than that (quite easy to achieve), just sent it to me and I will praise you on this so cool place that my blog is. Or if you have a suggestion about how I could improve it by myself, leave a comment, it will also be welcomed :).

To cool:

Check it :)

• Go around with a memory stick all the day.
• Use a online file-sync service.

For convenience, I use the second option. I have some files in the cloud, so they are always accessible and updated from any PC I use (three PCs at work and my laptop at home/wherever). In fact, I can even access them from my phone. For that, I greatly recommend Dropbox. I’ve already talked about it, but in Catalan, so I will make a short summary for English speakers (the Google translation is not so good).

How Dropbox works

1. Create an account.
2. Install the software on one computer (be the OS Linux, Windows or Mac).
3. Link the software to your account.
4. Decide which folder you want to sync. All the contents of the folder are uploaded to Dropbox servers, in real-time (well, as fast as your connection allows). Any modification/deletion/addition of files is automatically updated, with no user intervention.
5. Install the software on another computer.
6. Link again to your account.
7. Decide which folder to share. The contents of the folder are synchronised with the server, or what is the same: the two folders of your computers are always synchronized between them as soon as they have access to the network (usually, at boot up).
8. Repeat steps 5,6, 7 in many computers as you want.

Pros:

• No need to manually sync every time you modify the files, it is automatically done (you can check the sync status).
• You have local copies of the files, so you can work if network is not available.
• You can even access to your files via a web browser.
• Data transfer between server and clients is encrypted.

Cons:

• You have a local copies of the files on each computer, so it could be considered “wasted space” for some people (I prefer to say redundancy :) ).
• Dropbox workers could have a look at you files, even if they say they are not going to. They are on their servers, so…

Making Dropbox safer: Truecrypt is your friend

If you like the idea of using Dropbox, but you are worried about your privacy, or you have to store sensitive/confidential data, there is a solution to the dilemma. Do not share files; share encrypted files.

Truecrypt allows you to create encrypted partitions or containers. A container is a file which can be used as a partition or disk drive, encrypted and protected with a password. Actually, it can be encrypted with a password + a key file, but then you always need to have at hand this file for accessing to it. As I like lists a lot, I will explain how to use Truecrypt in this way.

To create your encrypted container:

1. Install Truecrypt software on you computer.
2. Execute it, and follow the wizard to create a virtual volume.
3. That’s all! :D

How to use the container:

1. Run Truecrypt.
2. Select the file (container) you have created before, and mount it.
3. Now you should have a new disk drive/partition available on you system. Copy files to it as you would normally.
4. Unmount the volume using Truecypt.

Quite simple, right? So, what’s the deal with Dropbox? You can put the encrypted container inside the Dropbox shared folder, so instead of getting access to all the files, they only receive a single encrypted file with no idea of what’s in there. Sure that they could try to crack it, but its like if somebody would like to hack your server by brute force (not impossible, but at least quite difficult).

To be sincere, there is a couple of drawbacks on that:

• You have to manually mount and unmount the encrypted file each time you want the data to be synced. While the volume is open, Dropbox will not sync it as it is considered to be “used by another application”.
• The sync is slower, as instead of just updating the files you have changed, it has to update the whole encrypted file.

I have found a balance between convenience and privacy putting on the encrypted volume just the sensitive files or personal data (e.g., pictures and documents), and outside of the container (but still inside the shared folder) the files that are not important but I want accessible and updated at all times.

Nowadays we use search engines a lot. They have become the standard way of finding websites on the jungle of information that the WWW is today. Web directories are a resource of the past, we just input our words of interest in a textbox, hit the Enter key, and rely on the answers of Google, Bing or Yahoo. They seem to work quite well, and they are free, so what’s wrong with them?

Just two things:

• You are getting a biased view of the web.
• Your telling A LOT about you to a company (and it’s third parties). Probably more than you would under other circumstances.

There is more out there.

When using a search engine, you are getting results according to its criteria. At the beginning, the results were sorted according to more or less objective parameters that measured the quality of the sites. But it has changed. You have probably noticed that you get different results for the same search when you use other computers or compare it with the results that other persons get. I could explain here why this happens, but the web page Don’t Bubble Us explains it with a lot of pictures, not much text and in a funny and easy to understand way. So, before continuing, please have a look at it (and then come back ;) ).

Done? Are you a bit disappointed about the search engine you use? I was. You have probably read the last part about DuckDuckGo, but I’ll talk about it later.

Searching for “herpes” is telling them (and other companies) that maybe you have it.

This is how it works. They know about your interests, your problems, what you are shopping… your life. Again, and in order to do not repeat what others have explained better, I recommend having a quick look at Don’t Track Us.

How do you prefer to be recognised?

So, now you could just be in the mood of “I don’t care about all this bullshit, you are a paranoid” or “OMG! I’m selling my life and having a distorted view of the world! I’ll never use it again.” Or something intermediate, just a bit worried and willing to find a better search engine that keeps your privacy while providing a good service.

Emergency services use dogs. I use ducks.

That’s the search engine I’m using, and the one I recommend: DuckDuckGo (DDG from now on). The have a very nice privacy policy, and I’m quite happy with the results. Actually, what they do is using other search engines to get a bunch of results, and then rank them according to its parameters of quality. So, we could say that they are acting as an anonimizer between you and several search engines.

In addition to that, they have some tricks that make the experience more enjoyable. One is the red box, also known as zero-click info. It is a red box (d’oh!) shown at the beginning of the search results, containing a topic summary or related topics.  It could be the explanation of an acronym, the result of a mathematical operation or conversion between units, a short definition, etc. I’ve solved several of my quick searches just with that, with no need to go inside other sites.

Zero-clik results for ESA

Next tip I love is the !bang. There are a set of keywords that allow you to perform specialized searches. You can !python to look at python documentaion, !mineforum for minecraft forum, !images for Google images (yes, they don’t provide this service yet), !filestube for search in filestube, etc. So, kind of shortcuts for other sites. And the list of options is huge.

To sum up this short review, to get an idea of the overall capabilities of DDG, try the searches on the goodies page.

Putting a duck in your life.

If you have decided to give DuckDuckGo a try, do not rely just on opening the web page each time. You are not going to do it. You will just use the search box in Firefox or the omnibox in Chrome/Chromium, therefore relying again on you previous search engine. To force yourself to use it for a while, you have to configure it as you default search engine on your browser. Fortunately, it’s really really easy, just a couple of clicks. If you visit the DDG homepage, you’ll see a link with the instructions to do it. So, do it. Now. If you don’t like it, you can always come back. But I haven’t ;)

Happy searching!