Write a video dvd from a video file in 4 commands

This is more a reminder for myself as I need to do it quite often and always forget how to do it:

ffmpeg -i mymovie.mp4 -target pal-dvd dvd.mpg
dvdauthor -o dvd/ -t dvd.mpg
(repeat if adding more movies)
dvdauthor -o dvd/ -T
growisofs -Z /dev/dvd -dvd-compat dvd/

Auto-analise de consumo elétrico

Outro dia tentei "dissecar" o nosso consumo elétrico aqui em casa, e ver o que isso representa comparado à média nacional e de outros países, e qual quantidade de painéis solares seria necessária para suprir esse consumo. As fontes de consumo listadas abaixo são todas tiradas da internet, tentei achar os dados mais precisos possíveis, mas deve ter obviamente vários dados errados ou desatualizados. Mesmo assim, tirei várias conclusões interessantes:

1) Até somos bastante eficientes, consumimos metade da média de São Paulo, um quarto da média da França, ou um décimo da média dos USA! Somando todos os aparelhos da casa, chego a 115 kwh/mês, a nossa conta da mais ou menos 110/mês, portanto a estimação deve ser mais ou menos correta.

2) Os nossos computadores realmente não consomem muita energia. O maior culpado, obviamente, é o chuveiro elétrico. Já li que botar o computador em modo "sleep" ou desliga-lo quase não faz diferencia, acho que é verdade. Note que desktops consomem muito mais que notebooks.

3) Precisariamos, no Brasil, apenas 10m² de painéis solares para produzir o que consumimos. O custo dessa instalação, infelizmente, gira em torno de R$ 50 000

4) Uma instalação solar não é interessante sozinha (produz pontualmente pouca energia demais, e não tem como armazenar eficientemente). O interessante é vender tudo que produz para a rede, e comprar o que usa. Na maioria dos países europeus (que é o modelo que se planeja seguir no Brasil), a lei obriga as companhias de energias a comprar o kwh de você mais caro do que vende. Nos USA é o inverso... Não consegui achar se já existe uma tarifa de compra no Brasil.

5) Nos países que mais incentivam o uso de energia solar (Alemanha), a proporção de energia disponível na rede elétrica que é produzida por casas particulares está começando a ficar consequente. O modelo está se comprovando. Tem vários projetos similares na mesa no Brasil, mas como no momento a produção de energia é mais que suficiente para atender o país, suponho que ninguém vê muita urgência nisso...

Aqui vai minha análise detalhada:

aparelho                 w           Kwh       horas/dia       Kwh

geladeira      1                                               27.3
chuveiro       1        5000                      0.5           75
lampadas       4         15                        4           7.2
notebook       2                     2.4                       4.8
Lava-roupas    1        250                       0.15         1.25

                                                              115.55

consumo                           Kwh / mês                 Kwh / ano
comparado

nossa casa                           110                       1320
média SP                             200                       2400
média Brasil                         150                       1800
média França                                                   4000
média UK                                                       3300
média USA                                                     14000

Insolação                         Kwh / ano                 kwh/ano/m²
média
Brasil                               1900                      190
São Paulo                            1700                      170
França                               1300                      130
Alemanha                             1100                      110

painéis              dimensões    Kwh / mês     preço R$   necessários
solares

Genérico              100x100        15.8                       7
Kyocera                140x60        25.2         3000          4
KC120

preço do kwh                       comprar                    vender
em R$
Brasil                               0.31
França                               0.25                      1.29
Portugal                             0.25                      1.45
USA                                  0.15                      0.03

5 new alpha textures

Get them on the textures page...

FreeCAD and SVG output

Putting your drawing on a SVG sheet in FreeCAD is beginning to work well. Here is a recent example:

In FreeCAD:


And the outputted SVG:


It is almost perfect, I still have a small problem regarding texts location (there is a shift between both), and the svg hatches which are not too good and for which I still didn't find a solution.

Download the .fcstd file here and the .svg file here.

More on FreeCAD, or Generative Components-like workflow on Linux

I did this interesting little chain yesterday, you might find it interesting. With a bit of trickery, you can really do some interesting parametric-generated architecture design on linux, only with open-source tools. And when I say architecture design, I mean the whole production chain, from conception to paper prints.

If you don't know Generative Components, it's a piece of software made to design architecture compositions based on sets of parameters that you can make evolve to create "beautiful" parametric-looking structures... I recently discovered an amazing application called StructureSynth which does exactly that: create geometry based on parameters and rules.

You design simple rules in a very simple language, such as: "Rule n°1: move 2 units in x, rotate 15° in y, then create a box, then reapply Rule n°1". Then, all the magic is here: You can specify another, different Rule n°1. The program will interpolate both randomly, and create randomic variations:



The version of StructureSynth in the Debian repositories comes with a set of exporters for different renderers such as Sunflow, and Blender, (with the help of a blender import script) which I used here to import the geometry:



The blender import script imported all the geometry as one single object, so I first separated it in original parts (Edit mode, select all, P -> separate all loose parts), then exported it as an .obj file, that < href=http://free-cad.sf.net>FreeCAD can read. Of course the blender import script could easily be adapted to FreeCAD so we could skip the Blender step, but I found it interesting to show how the geometry passes from one to another without any data loss.



FreeCAD can work with several types of geometry. Our .obj file was imported as Meshes, but much more interesting is to work with bRep objects, which are FreeCAD's "native" object type, and permit much more complex functionality (they have the notion of "solid", so boolean ops work perfectly, they can have real curved surfaces, etc). So I converted my meshes to brep parts with a macro, and added a couple of lines just to show you how 3D and 2D begin to mix well in FreeCAD.

The Draft module in FreeCAD can already give you nice results when putting your scene geometry on a sheet. Of course the Draft module is made for 2D, so you'll notice the 3D parts are not displaying very correctly (face inversions, mostly), but that problem will be addressed soon.



To show you better the possibilities of the Geometry-to-paper process, I did another example. It suffers the same problems as the one above, but the control over display (colors, line width, texts, etc...) begins to be good.



This is a quick structure I did just to play with the process, and here is the SVG output:



SVG files already carry informations such as paper size, and it is as reliable as pdf (you can easily turn them as pdf with apps that support svg such as Inkscape or directly from FreeCAD). At the moment the informations in the template (Project author, etc...) cannot be edited directly from within FreeCAD, so you need to edit your sheet in another app, but that also will probably be addressed one of these days.

What's new on the FreeCAD front

There are several cool new things coming to FreeCAD so I decided to show you a bit of what's going on. Most of this stuff will be in the 0.11 release (no release date prevision, it's done when it's done). There is a 0.11 preview installer for windows on the FreeCAD website, otherwise you'll have to wait a bit (or compile FreeCAD yourself if you are brave enough). I'll focus more on the 2D part, since it's what I'm mostly doing there...

The most interesting thing that has been added recently by Werner is python-driven Part objects. Unlike the older python Document objects, where you had to do everything, compute the geometry, and define how that geometry gets displayed in the 3D scene, the new Part python objects automatically display their geometry the "standard FreeCAD way". That allows for extremely simple python objects such as this:

class Line:
    def __init__(self, obj):
        ''' App two point properties '''
        obj.addProperty("App::PropertyVector","p1","myCategory","Start point")
        obj.addProperty("App::PropertyVector","p2","myCategory","End point").p2=FreeCAD.Vector(1,0,0)
        obj.Proxy = self
 
    def execute(self, obj):
        ''' Print a short message when doing a recomputation, this method is mandatory '''
        obj.Shape = Part.makeLine(obj.p1,obj.p2)
 
ml=FreeCAD.ActiveDocument.addObject("Part::FeaturePython","myLine")
Line(ml)

As a result, the 2D drafting module has been completely upgraded to take advantage of this. One of the most useful consequences is that it now has an editmode. But it also allows for several other goodies, such as enter FreeCAD's parametric chain (for example, an object made of the union of two other objects retains the original objects, etc):



Because of this, the use of the Drawing module is now much easier, and you can already output much better sheets:





Another area that is being currently worked on by Jürgen is the Sketcher, which allows you to draw constrained 2D shapes. There is still not much new stuff visible, but it has been almost rewritten from scratch, and is now much more stable and works on all platforms. Now really the sketcher can be used to build geometry.



Of course all this is pretty new and lots of bugs are expected to appear, but we come everyday closer to the day we can start to do serious productive work with FreeCAD. As a sidenote, one of the things we lack badly is bug reporting. If you happen to find a bug, if you make FreeCAD crash and can reproduce the cause of the crash, don't hesitate and add a report to the bug tracker. This is a very important for FreeCAD to reach some stability...

Working with blender looks cooler than sketchup

One image is worth thousand words

World cup stadiums in the blender game engine

This is a job we've recently made with Chico Ortiz for an exhibition currently running at the SESC Pompéia in São Paulo, until 30th of June.

The idea was to show a couple of stadiums interactively, so you can see their shape and surroundings, then enter them and experiment how it feels to play football there... Maíra and me made the modeling, while Chico made the game logic, python scripting, the menus and all the game system. Everything runs in the blender game engine, and is displayed in 2 consoles in the expo (on first floor, next to the spiral stair):











Here is a video of the in-game feel...

And last but not least, here are the files! Here are the 4 stadiums (74Mb zip file). In short we'll put the complete game files...

I also made a fluxbox theme with that image...

Automounting usb devices with udev only

Fiddling a little bit with udev rules to automount usb drives. Udev is just amazing, can do about whatever you want!
The following rules must be added to one of the .rule files in /etc/udev/rules.d (for example: 98usb-storage.rule):

#Custom USB Mounting
ACTION=="add", KERNEL=="sdb[1-9]", DRIVERS=="usb-storage", NAME="%k"
ACTION=="add", KERNEL=="sdb[1-9]", DRIVERS=="usb-storage", SYMLINK+="usbdisk-%k", GROUP="plugdev"
ACTION=="add", KERNEL=="sdb[1-9]", DRIVERS=="usb-storage", RUN+="/bin/mkdir -p /media/%k"
ACTION=="add", KERNEL=="sdb[1-9]", DRIVERS=="usb-storage", RUN+="/bin/chown root:plugdev /media/%k"
ACTION=="add", KERNEL=="sdb[1-9]", DRIVERS=="usb-storage", RUN+="/bin/chmod 775 /media/%k"
ACTION=="add", KERNEL=="sdb[1-9]", DRIVERS=="usb-storage", RUN+="/bin/mount -t vfat -o 
noauto,rw,user,uid=1000,gid=1/dev/%k /media/%k"

ACTION=="remove", KERNEL=="sdb[1-9]", RUN+="/bin/umount -l /media/%k"
ACTION=="remove", KERNEL=="sdb[1-9]", RUN+="/bin/rmdir /media/%k"

Info comes from here:
http://reactivated.net/writing_udev_rules.html
http://wiki.archlinux.org/index.php/Udev

Simple python code browser in emacs

On my way through perfect emacs setup...
It's actually much easier than I thought. Just install speedbar from your software repository, then put sr-speedbar.el in your lisp folder, and add this to your .emacs file:

(require 'sr-speedbar)

then, invoke it with M-x sr-speedbar-open. Navigate with arrows, expand with Space and jump to item with Return... Complete info here...

Playing with FreeCAD...

I just made this little "thing" while searching for a cool new splash screen. I got very impressed by Form:uLA yesterday (specially this work)... Kind of 3D Lebbeus Woods...







The FreeCAD file is here...

Small update to fluxtwitter... It now takes a default icon from monsterID if the user avatar cannot be loaded...
http://yorik.uncreated.net/scripts/fluxtwitter.py

Playing with the wacom

Following the example of Chico & Cícero, I got myself a new wacom tablet (bamboo pen&touch), what a difference with the (RIP) genius... The touch is completely different, the pentip and the pas surface are much harder and the pen can be tilted very low. The touchpad is a bit annoying (sometimes it detects a hand movement while you are drawing), so I quickly set up a mechanism to disable it. The installation under linux was a bit of pain, but now it works like a charm. And it has an eraser. Here are the first drawings I did with it...











For who is struggling to install the thing under linux, I wrote my method here:
http://forums.debian.net/viewtopic.php?f=16&t=51279

fluxtwitter upgrade

I made a small upgrade to my little twitter app, you can now have tweets stack up until you read them. When you close the window, the list gets reduced to the normal number of tweets. Get new version here:
http://yorik.uncreated.net/scripts/fluxtwitter.py

2 more "randomic creations"... First one made with harmony, other one with alchemy...

Drawn in less than 2 minutes with Harmony



http://storage.dangertree.net/harmonyStrokes/harmony.html

Blender 2.50 and 2.49 together

A couple of days ago, the 2.49 scripts were removed from the blender trunk version (2.50). This means that when you install the 2.50 version, the 2.49 won't work fully anymore. But it is quite easy to make both work side by side:

- The user settings aready use different files (.B.blend for 2.49 and .B25.blend for 2.50) so nothing to worry about
- The scripts folders can be set to a custom path. What I do is to keep the standard .blender folder for 2.50 so it gets updated when I recompile (actually it is a link to the .blender folder inside my compilation folder), and I created a .blender24 folder, containing the old scripts. Then, in blender 2.49, set the script path to that one in the preferences, and the job is done!
- You can then create two different links (or two different launch icons) to the two blender executables. If you are on linux, you can even create a "blender" link in your /home/user/bin folder pointing to the blender 2.50 executable, so it overrides your system-installed blender...

Switching to blender 2.5



The new blender version 2.50 is now in sufficient good shape to be fully customized, and to me that was a very important point. So I swapped my main work version to the new one. Of course, since several functions are still not there (and specially almost all the python scripts), it's good to keep a 2.49 version around for a couple of months.

I had a bit of trouble understanding how to change the default theme (You must go into the outliner, set it to display the user preferences, then navigate to the theme and replace the theme name "Blender" by another name, which will create a new - editable - theme.

Other small thing was the middle mouse button that rotates the view instead of panning. Same thing here, you must export the default keymap, then change its name and reimport it, in order to create an editable keymap. Then, swap the view2d.pan and view3d.rotate values.

I still cannot seem to export my new theme, but as soon as it works I'll post it around here...

Lecture at the Campus Party 2010



for who'll be around, I'll be giving a lecture about blender and architecture at the Campus Party in são Paulo , on January 28th, at 16h00...

dwg to dxf converter for linux

This python application converts a dwg file to a dxf 2007 file with same name. To use it, you must have wine installed, and set the correct path to the EveryDWG utility by editing this script. The EveryDWG utility can be downloaded free of charge from the opendwg website but you must agree to their license terms before downloading.

Instructions and download here.

dxf thumbnailer for linux



This application generates a 128x128px PNG image showing the contents of a DXF file. In order to speed up the image generation process, only a few types of entities are read, so complex files might not get rendered accurately or even fail to render. In order to use this program, you must configure your file manager to use it as a thumbnailer for dxf file type (mime type: image/x-dxf).

Instructions and download here.

Good, free games on linux

I decided to write this article to show a couple of games I like, that are free and run on linux. I am not trying to do a "10 best linux games" article (Try searching for "best linux games" on google, you'll find many cool things), but rather to illustrate a couple of games that I like much, that are free and run on linux. The linux gaming scenery is evolving quite well now, aside the traditional open-source games, more and more commercial games are beginning to support the linux platform. But nothing like those good old free ones that are always around...

1. Flightgear: A realistic flight simulator, for a zen & relaxing time



FlightGear is today a gorgeous flight simulator. It exists since a long time already, and always had amazing features like an excellent flight model, many fan-made airplane and the whole world available to fly over. Recently they made a total conversion of the graphics system and, even if the sceneries still don't match more famous professional games, the realism is now quite high. There is also a meteorologic system that takes real-time info from the net, multiplayer connection, a mapping utility, etc. Only for flight sims passionates probably, but I like it much.

Website: http://www.flightgear.org/
In-game video: http://www.youtube.com/watch?v=QOgSoeCxXb0
How to install: Directly from the Debian/Ubuntu software repository
Additional downloads: Sceneries,planes

2. OpenArena: A give-me-blood-immediately adrenaline-rich first-person shooter



OpenArena is a first-person shooter, similar to Quake. Actually it is built upon an earlier version of the Quake 3 engine, thanks to the cool attitude of the Quake developers who release older versions of their engine for free. Thanks to that, OpenArena can use the wide amout of Quake 3 maps. OpenArena is a simple, intense, multiplayer adrenaline-pushing game. It is best played on the internet, against other humans, but you can also play alone against bots. Although graphically pretty simple compared to commercial games, it is one of the most widespread 1st-person shooters on linux, so you always find intense battles on the net to merge into.

Website: http://www.openarena.ws/
In-game video: http://www.youtube.com/watch?v=lCeGTniBOj8
How to install: Directly from the Debian/Ubuntu software repository.
Additional downloads: maps, more maps.
Try also: Sauerbraten, Nexuiz, Tremulous, Assault-Cube

3. TA Spring: A glorious and gorgeous real-time strategy game



Total Annihilation Spring started as a project to reuse the assets of the famous comercial game Total Annihilation, but in a modern 3D environment. Since then, it has now evolved into something much bigger, a complete Real Time Strategy engine. You can plug in it the original TA game assets, but also many other games, mods, maps, availables on the net. It is a modern, graphically rich, multiplayer RTS game. You can play on the internet, in a local network or alone against bots. The installation is a bit hard, but once you succeed you get your reward...

Website: http://springrts.com/
In-game video: http://www.youtube.com/watch?v=H1K6Y9fYY94
How to install: Follow this guide.
Additional downloads: Once Spring is installed, you need to add games and maps.

4. FreeCiv: One of the best games ever...



Everyone knows the famous Civilization, right? I'm surely not the only one to pretend it was the best computer game ever made until today. You must grow your civilization militarily, scientifically, politically and commercially, so you crush the other civilizations and take the control of the world, simple as that. This is a free (and somewhat "bettered") version that allows multiplayer games, several game types, etc...

Website: http://freeciv.wikia.com/wiki/Main_Page
In-game video: http://www.youtube.com/watch?v=_LM0MEyTwH8
How to install: Directly from the Debian/Ubuntu software repository.

5. Warzone 2100: Another classic revived.



Whoever already played Warzone 2100 will never forget the thunder of the howitzer gun on the plains. This is quite an old game, with simple graphics compared to today games, but few real-time strategy games have been able to render the battlefield with so much intensity. It is a typical RTS, harvest for resources, build your base, research new weapons, build units and crush the enemy, but it is one of the best. Warzone 2100 was once a commercial game, but has some time ago been released under a GPL license, and is now maintained by volunteers.

Website: http://wz2100.net/
In-game video: http://www.youtube.com/watch?v=98BoUFS7UZM
How to install: Directly from the Debian/Ubuntu software repository.

6. Regnum Online: A state-of-the-art free MMORPG



Regnum online is there since some time already but has been steadily improved over time and has now quite impressive graphics. It is a classical Massive Multiplayer Online Role-playing Game like World of Warcraft or Archlord. You begin alone, but quickly you need to team up with other players to achieve quests, you begin to form small militias with those people who become your friends, and eventually you enter wars against other player groups... If you never played a MMORPG, have definitely a try. The game is totally free, and they send goodies (special weapons, etc) on the website too, but that are absolutely not necessary.

Website: http://www.regnumonline.com.ar/
In-game video: http://www.youtube.com/watch?v=6Rl8SDv4ABw
How to install: They have their own installer here. You must create an user on the website too.

7. Privateer: "Die by the fielthy weapon you adore!"



Privateer is an old space fighter game based on the Wing Commander serie. Differently to Wing Commander, where you were a military space fighter pilot in a war, in Privateer you are a free-lancer pilot, taking missions from spaceport to spaceports. You do the missions for money, which you spend in arming and upgrading your spaceship. This version is an excellent remake of the original game.

Website: http://privateer.sourceforge.net/
In-game video: http://www.youtube.com/watch?v=88TPOvBwo3Q
How to install: They have their own installer here
Try also: Vega Strike

8. Beneath a Steel Sky: Where are the adventure games gone today?



I don't know about you, but I'm too sad the times of the good old adventure games, where you had good laughs trying to solve absurd problems in cool 2D landscape are gone... I spent hours on that type of games. Fortunately there is an open-source engine called SCUMM that is able to play several of those games. Beneath a steel sky was one I had never finished at that time, and, besides the old-time low-res graphics, I enjoyed much in retaking.

Website: None
In-game video: http://www.youtube.com/watch?v=pm7V-VrlJuo
How to install: Directly from the Debian/Ubuntu software repository.
Try also: The Flight of the Amazon Queen, Day of the Tentacle

9. Shadow of the Comet: Abandonware!



Abandonware designates those old, I mean VERY old games, that are not technically free, but that have been abandoned by the publisher, so nobody cares anymore if you download and play the game. There are thousands of those someties excellent games on sites like Abandonia or Abandonwareme. Usually they were not made directly for linux or any other modern OS, so you must run them inside an emulator such as dosbox. Don't expect good graphics, but expect good games. Shadow of the Comet is a slow-paced, creepy lovercraft-style adventure I liked a lot.

Website: None
In-game video: http://www.viddler.com/explore/coulis/videos/2/.
How to install: Install dosbox first, then download the game from any abandonware site, unzip it and run its executable file like this from the terminal: dosbox /path-to/GAME.EXE
Try also: Eye of the Beholder, Dune 1, Flashback, Wing Commander, Pirates!

10. Urban Terror: A free Counter-strike



This is a first-person shooter, similar to OpenArena, but made only for 2-teams (SWAT vs terrorists) game. You cannot play alone, you need to enter an internet game or create your own with friends. It is based on the Quake3 engine, and is really as good as the original counter-strike game.

Website: http://www.urbanterror.net/
In-game video: http://www.youtube.com/watch?v=zjowhAU3mg4
How to install: They have their own installer here

More...

More and more, games on linux are becoming decent. An excellent place to keep in your bookmarks (or add to your repositories!) is playdeb or the ubuntu gamers arena.

Have fun!