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11 de Fevereiro de 2010, 0:00 , por Desconhecido - | Ninguém está seguindo este artigo ainda.

Gustavo Noronha (kov): CEF on Wayland

22 de Dezembro de 2017, 11:25, por Planeta GNOME Brasil - 0sem comentários ainda

TL;DR: we have patches for CEF to enable its usage on Wayland and X11 through the Mus/Ozone infrastructure that is to become Chromium’s streamlined future. And also for Content Shell!

At Collabora we have recently done some work for a customer who wanted to upgrade their system from X11 to Wayland. The problem: they use CEF as a runtime for web applications and CEF was not Wayland-ready. They also wanted to have something which was as future-proof and as upstreamable as possible, so the Chromium team’s plans were quite relevant.

Chromium is at the same time very modular and quite monolithic. It supports several platforms and has slightly different code paths in each, while at the same time acting as a desktop shell for Chromium OS. To make it even more complex, the Chromium team is constantly rewriting bits or doing major refactorings.

That means you’ll often find several different and incompatible ways of doing something in the code base. You will usually not find clear and stable interfaces, which is where tools like CEF come in, to provide some stability to users of the framework. CEF neutralizes some of the instability, providing a more stable API.

So we started by looking at 1) where is Chromium headed and 2) what kind of integration CEF needed with Chromium’s guts to work with Wayland? We quickly found that the Chromium team is trying to streamline some of the infrastructure so that it can be better shared among the several use cases, reducing duplication and complexity.

That’s where the mus+ash (pronounced “mustache”) project comes in. It wants to make a better split of the window management and shell functionalities of Chrome OS from the browser while at the same time replacing obsolete IPC systems with Mojo. That should allow a lot more code sharing with the “Linux Desktop” version. It also meant that we needed to get CEF to talk Mus.

Chromium already has Wayland support that was built by Intel a while ago for the Ozone display platform abstraction layer. More recently, the ozone-wayland-dev branch was started by our friends at Igalia to integrate that work with mus+ash, implementing the necessary Mus and Mojo interfaces, window decorations, menus and so on. That looked like the right base to use for our CEF changes.

It took quite a bit of effort and several Collaborans participated in the effort, but we eventually managed to convince CEF to properly start the necessary processes and set them up for running with Mus and Ozone. Then we moved on to make the use cases our customer cared about stable and to port their internal runtime code.

We contributed touch support for the Wayland Ozone backend, which we are in the process of upstreaming, reported a few bugs on the Mus/Ozone integration, and did some debugging for others, which we still need to figure out better fixes for.

For instance, the way Wayland fd polling works does not integrate nicely with the Chromium run loop, since there needs to be some locking involved. If you don’t lock/unlock the display for polling, you may end up in a situation in which you’re told there is something to read and before you actually do the read the GL stack may do it in another thread, causing your blocking read to hang forever (or until there is something to read, like a mouse move). As a work-around, we avoided the Chromium run loop entirely for Wayland polling.

More recently, we have start working on an internal project for adding Mus/Ozone support to Content Shell, which is a test shell simpler than Chromium the browser. We think it will be useful as a test bed for future work that uses Mus/Ozone and the content API but not the browser UI, since it lives inside the Chromium code base. We are looking forward to upstreaming it soon!

PS: if you want to build it and try it out, here are some instructions:

# Check out Google build tools and put them on the path
$ git clone
$ export PATH=$PATH:`pwd`/depot_tools

# Check out chromium; note the 'src' after the git command, it is important
$ mkdir chromium; cd chromium
$ git clone -b cef-wayland src
$ gclient sync  --jobs 16 --with_branch_heads

# To use CEF, download it and look at or use the script we put in the repository
$ cd src # cef goes inside the chromium source tree
$ git clone -b cef-wayland
$ sh ./cef/ # NOTE: you may need to edit this script to adapt to your directory structure
$ out/Release_GN_x64/cefsimple --mus --use-views

# To build Content Shell you do not need to download CEF, just switch to the branch and build
$ cd src
$ git checkout -b content_shell_mus_support origin/content_shell_mus_support
$ gn args out/Default --args="use_ozone=true enable_mus=true use_xkbcommon=true"
$ ninja -C out/Default content_shell
$ ./out/Default/content_shell --mus --ozone-platform=wayland

Gustavo Noronha (kov): Who knew we still had low-hanging fruits?

16 de Outubro de 2017, 18:23, por Planeta GNOME Brasil - 0sem comentários ainda

Earlier this month I had the pleasure of attending the Web Engines Hackfest, hosted by Igalia at their offices in A Coruña, and also sponsored by my employer, Collabora, Google and Mozilla. It has grown a lot and we had many new people this year.

Fun fact: I am one of the 3 or 4 people who have attended all of the editions of the hackfest since its inception in 2009, when it was called WebKitGTK+ hackfest \o/


It was a great get together where I met many friends and made some new ones. Had plenty of discussions, mainly with Antonio Gomes and Google’s Robert Kroeger, about the way forward for Chromium on Wayland.

We had the opportunity of explaining how we at Collabora cooperated with igalians to implemented and optimise a Wayland nested compositor for WebKit2 to share buffers between processes in an efficient way even on broken drivers. Most of the discussions and some of the work that led to this was done in previous hackfests, by the way!


The idea seems to have been mostly welcomed, the only concern being that Wayland’s interfaces would need to be tested for security (fuzzed). So we may end up going that same route with Chromium for allowing process separation between the UI and GPU (being renamed Viz, currently) processes.

On another note, and going back to the title of the post, at Collabora we have recently adopted Mattermost to replace our internal IRC server. Many Collaborans have decided to use Mattermost through an Epiphany Web Application or through a simple Python application that just shows a GTK+ window wrapping a WebKitGTK+ WebView.


Some people noticed that when the connection was lost Mattermose would take a very long time to notice and reconnect – its web sockets were taking a long, long time to timeout, according to our colleague Andrew Shadura.

I did some quick searching on the codebase and noticed WebCore has a NetworkStateNotifier interface that it uses to get notified when connection changes. That was not implemented for WebKitGTK+, so it was likely what caused stuff to linger when a connection hiccup happened. Given we have GNetworkMonitor, implementation of the missing interfaces required only 3 lines of actual code (plus the necessary boilerplate)!


I was surprised to still find such as low hanging fruit in WebKitGTK+, so I decided to look for more. Turns out WebCore also has a notifier for low power situations, which was implemented only by the iOS port, and causes the engine to throttle some timers and avoid some expensive checks it would do in normal situations. This required a few more lines to implement using upower-glib, but not that many either!

That was the fun I had during the hackfest in terms of coding. Mostly I had fun just lurking in break out sessions discussing the past, present and future of tech such as WebRTC, Servo, Rust, WebKit, Chromium, WebVR, and more. I also beat a few challengers in Street Fighter 2, as usual.

I’d like to say thanks to Collabora, Igalia, Google, and Mozilla for sponsoring and attending the hackfest. Thanks to Igalia for hosting and to Collabora for sponsoring my attendance along with two other collaborans. It was a great hackfest and I’m looking forward to the next one! See you in 2018 =)

Vicente Aguiar: Da contracultura à cibercultura: Uma reflexão sobre o papel dos hackers.

10 de Julho de 2017, 18:35, por Planeta GNOME Brasil - 0sem comentários ainda

Da contracultura   cibercultura  uma reflex o sobre o papel dos hackers.

Com o início do século XXI, estamos vivendo um desses raros intervalos na história. Um período em que a base tecnológica das nossas relações em sociedade está — e tudo indica que continuará por um bom tempo — imersa num intenso processo de transformações tecnológicas e culturais. Assim, de forma semelhante ao que aconteceu no século XIX, com a revolução industrial e o surgimento da produção em série mediada por máquinas, as novas tecnologias de informação e comunicação, em especial a internet, revolucionam os meios de comunicação humana, como também alicerçam transformações nas mais diversas áreas da vida em sociedade.

Tendo a liberdade de acesso, produção e compartilhamento de informações como um dos grandes princípios estruturantes, as mudanças propiciadas pelos liames digitais da internet representam até o surgimento de um novo paradigma tecnológico, de uma nova Era Pós-Industrial.

Contudo, cientistas sociais, como Manuel Castells e Fred Turner, nos lembram que não existem revoluções de natureza tecnológica que não sejam precedidas de transformações culturais. Como tecnologias revolucionárias têm que ser pensadas, elas não são o resultado de um simples processo técnico ou incremental, mas sim fruto de pensamentos libertários e subversivos que são, por exemplo, ligados a gestos de rebeldia e desobediência civil. Dentro desse entendimento, esses mesmos autores afirmam que existe uma relação estreita entre os movimentos de contracultura dos anos 60 e a cibercultura libertária dos nossos dias.

Para além dos festivais de música e das manifestações do movimento hippie, os princípios de liberdade de expressão que marcaram essa época também se fizeram presente ao longo de todo o processo de criação e difusão da internet pelo que hoje é denominado de “cultura hacker”. Todavia, antes de seguirmos adiante nessa história, faz-se necessário esclarecer certa ambiguidade ou mal-entendido sobre o termo e a práxis social dos hackers. Afinal, na sua origem, o termo hacker não está associado a indivíduos irresponsáveis que invadem sistemas computacionais de forma ilícita — como é normalmente propagado pela mídia de massa mais tradicional. Esses sujeitos que violam sistemas de segurança e quebram códigos computacionais são, especificamente, denominados de “crackers” e, em geral, são também repudiados pelas comunidades de hackers. É claro que todo “cracker” já foi um hacker e isso possibilita que formadores de opinião — como, por exemplo, o jornalista e produtor cultural Nelson Motta — afirmem que todo hacker seja sim um cracker.

No entanto, de forma contrária a uma visão mais restrita que tenha como base o exemplo de alguns poucos crackers que ganharam fama no mundo por conta de invasões espetaculares em poderosos computadores corporativos, esse artigo tenta ir um pouco além desse entendimento. Em especial, buscamos resgatar a visão do filósofo finlandês Pekka Himanen e os artigos de um dos integrantes da própria comunidade hacker, Eric Raymond, que reforçam a importância desses primeiros “nativos digitais” como uma importante expressão cultural contemporânea de caráter libertário e inovador. Isto porque os hackers estão vinculados a um conjunto de valores e crenças que emergiram, num primeiro momento, das redes de pessoas que desenvolviam softwares e interagiam em redes computacionais em torno da colaboração em projetos de programação criativa. Isso significa, então, partir de um entendimento que essa cultura hacker desempenhou um papel central ao longo da história de desenvolvimento dos principais símbolos tecnológicos da atual sociedade em rede, como os primeiros computadores pessoais (PCs), a internet e os primeiros sistemas operacionais, como o UNIX. E essa cultura criativa perdura até o presente momento de forma pulsante. Afinal, inúmeras pesquisas demonstram como os hackers sustentam o ambiente fomentador de inovações tecnológicas significativas, mediante a colaboração e comunicação on-line, como também acaba permitindo a conexão entre o conhecimento originado em universidades e centros de pesquisas com os produtos empresariais que difundem as tecnologias da informação no “mundo dos átomos” — isto é, na materialidade da economia contemporânea.

Tendo a liberdade técnica de acesso, uso, compartilhamento, modificação e criação como valor supremo, a cultura hacker se manifesta em diversas áreas por meio de uma nova ética de trabalho, que lança alguns “enigmas contemporâneos” sobre o comportamento e as próprias relações sociotécnicas na realidade contemporânea. Mais especificamente, esse suposto comportamento enigmático, em termos de engajamento digital, emerge a partir de questões como: quais os valores que levam hoje milhares de tecnólogos a desenvolverem um software de alta complexidade como o Linux, na maioria dos casos de forma voluntária, além de o distribuírem de forma livre pela internet? Ou ainda, o que exatamente impulsiona milhares de wikipedistas de diversas partes do mundo a se juntarem na internet de forma colaborativa para criar e compartilhar conhecimento de forma livre e gratuita, por meio de um projeto enciclopédico internacional?

Umas das respostas mais encontradas em pesquisas sobre essa temática é que os hackers trabalham e se engajam em projetos dessa natureza, antes de tudo, porque os desafios técnicos e intelectuais são interessantes. Problemas encontrados no processo de criação de um determinado bem causam uma forte curiosidade e atração para essas pessoas, tornando-as sempre ávidas por mais conhecimento para criar ou encontrar uma solução inovadora. Essa atividade de produção exerceria então um poder de fascínio sobre esses sujeitos envolvidos pela cultura hacker, a ponto de o próprio trabalho, em determinadas condições, servir como um momento de se “recarregar as energias” — por mais contraditório que isso possa parecer num primeiro momento. Assim, para definir o princípio que rege as atividades de um indivíduo que se afirma como um hacker, o Linus Torvalds (hacker criador do Linux) acredita que as palavras “paixão” e “diversão” podem descrever bem a força lúdica que move ele a dedicar horas de um trabalho que muitas vezes é empreendido no “tempo livre”.

Por conta disso, não é difícil perceber que esta relação passional com o trabalho não é privilégio dos hackers de computador. Muito ao contrário. Em seu guia Como Tornar-se um Hacker, Eric Raymond também afirma que é possível encontrar outros tipos de hackers entre diversas áreas. “Há pessoas que aplicam a atitude hacker em outras coisas, como eletrônica ou música — na verdade, você pode encontrá-la nos níveis mais altos de qualquer ciência ou arte. Hackers de software reconhecem esses espíritos aparentados de outros lugares e podem chamá-los de ‘hackers’ também — e alguns alegam que a natureza hacker é realmente independente da mídia particular em que o hacker trabalha”.

Por exemplo, há vários pontos de contato entre tecelões, artesãos e a cultura hacker. Isto porque é possível perceber que todos eles (tecelões, artesãos e hackers) comungam de muitos valores inerentes ao trabalho criativo e coletivo, como, por exemplo, o compartilhamento do conhecimento que fundamenta o processo da produção de um bem ou uma obra — além, é claro, do prazer e da alegria inerente ao ato da criação em si. Afinal, o que seria, por exemplo, da gastronomia mundial sem o antigo hábito popular de se compartilhar receitas de culinária para se adaptar e criar novos e saborosos pratos pelos chefes de cozinha.

Richard Stallman, fundador da Free Software Foundation, ressalta, então, que um hacker é antes de tudo alguém que ama o que faz e, por conta disso, busca sempre inovar e explorar novas possibilidades no exercício do seu ofício em colaboração com seus pares. Isso significa dizer que um hacker, como individuo, busca sempre não apenas usar, mas principalmente aprimorar e aperfeiçoar o objeto de sua paixão, no contexto de um setor, organização ou comunidade da qual interage e participa. Para isso, o acesso irrestrito e o compartilhamento do conhecimento associado ao uso e ao processo de produção de um bem em questão é para um hacker, da mesma forma que para seus pares, uma condição vital da sua práxis social.

Dentro dessa perspectiva, esse ímpeto lúdico e colaborativo permite aos hackers romperem com uma dimensão clássica dos sistemas criativos da modernidade industrial: a separação entre quem usa e quem cria, aperfeiçoa ou produz um determinado bem. Em outras palavras, isso significa que a cultura hacker supera a clássica dicotomia entre “criadores” e “usuários”, pois partem de uma (antiga) premissa produtiva: os usuários são a base de toda a organização criativa somente por uma simples razão: todos os criadores eram usuários antes de começarem a contribuir com suas criações.

* Texto originalmente publicado na Revista Objectiva.

Jonh Wendell: Fedora 26 não conecta no wireless

20 de Abril de 2017, 19:17, por Planeta GNOME Brasil - 0sem comentários ainda

Esta é uma dica rápida caso você, assim como eu, tenha o mesmo problema ao instalar o Fedora 26 (alfa).

O instalador não conseguiu conectar no meu roteador wireless, um D-Link. Mais especificamente, ele não estava recebendo um endereço IP do roteador. Ao que parece, um problema relacionado a DHCP.

Se for este o caso, abra um terminal (pressione a tecla Windows, digite “Terminal” e aperte Enter), e digite o seguinte comando:

sudo sh -c 'echo "send dhcp-client-identifier = hardware;" > /etc/dhcp/dhclient.conf'

Agora reconecte na rede wireless. Depois do primeiro boot – com o sistema já instalado – repita o comando acima, uma única vez.

A propósito, esse bug não é recente. Aconteceu comigo no Fedora 25, mas somente no sistema instalado. Dentro do instalador tudo funcionou perfeitamente. Agora, no F26, tá acontecendo desde o começo. Aqui o link do bugzilla, para os curiosos:

Espero ter ajudado. Bom Fedora pra vcs!

Vicente Aguiar: Rede Suiça de Educação Artística adere ao Noosfero

13 de Março de 2017, 3:23, por Planeta GNOME Brasil - 0sem comentários ainda


A rede internacional Another Roadmap for Arts Education (Outro Roteiro para a Educação Artística), que reúne educadores/as e pesquisadores/as em museus, universidades, escolas e projetos culturais e educativos passou a utilizar o Noosfero como plataforma de articulação e comunicação entre seus núcleos ao redor do mundo. A rede agrega 22 grupos ao redor do mundo com a proposta de trabalhar a educação artística inserida nas relações sociais e políticas, respeitando os contextos locais.

Another Roadmap surgiu do anseio de educadores/as e pesquisadores/as de fazer uma análise crítica do Roteiro para a Educação Artística da Unesco, definido em 2006, e da Agenda de Seul (2010), uma série de metas mundiais para o desenvolvimento da Arte e Educação. A rede, que deu início à Another Roadmap School (Escola Outro Roteiro), tem a perspectiva de questionar a hegemonia dos conceitos ocidentais de arte e educação e elaborar alternativas e novos paradigmas para as pesquisas e práticas relacionadas à educação artística.

A plataforma utilizada pela rede foi desenvolvida pela Colivre por meio de um serviço prestado à Universidade de Artes de Zurique na Suiça. Por utilizar o Noosfero, a plataforma permite autonomia para os grupos que fazem parte da rede porque possibilita que cada perfil de comunidade e usuário na rede possa ter seu próprio layout customizado além de possuir funcionalidades de blogs, fóruns, agendam, wiki, pastas de arquivos, galeria de imagens, entre outras.

O Noosfero é uma plataforma web livre para a criação de redes sociais autônomas com foco no compartilhamento de conteúdo. Desenvolvido pela Colivre e lançado em 2009 durante o III Encontro Nordestino de Software Livre, o Noosfero já garantiu o primeiro lugar em diversos prêmios nacionais à cooperativa como o 9º Prêmio Cooperativa do Ano em 2014, o Prêmio Pontos de Mídia Livre do Ministério da Cultura em 2015 e o Prêmio Especial Recursos Educacionais Abertos da Revista ARede Educa em 2016.

Para conhecer mais sobre a rede Another Roadmap for Arts Education acesse o site oficial através do endereço

Gustavo Noronha (kov): A tale of cylinders and shadows

21 de Novembro de 2016, 17:04, por Planeta GNOME Brasil - 0sem comentários ainda

Like I wrote before, we at Collabora have been working on improving WebKitGTK+ performance for customer projects, such as Apertis. We took the opportunity brought by recent improvements to WebKitGTK+ and GTK+ itself to make the final leg of drawing contents to screen as efficient as possible. And then we went on investigating why so much CPU was still being used in some of our test cases.

The first weird thing we noticed is performance was actually degraded on Wayland compared to running under X11. After some investigation we found a lot of time was being spent inside GTK+, painting the window’s background.

Here’s the thing: the problem only showed under Wayland because in that case GTK+ is responsible for painting the window decorations, whereas in the X11 case the window manager does it. That means all of that expensive blurring and rendering of shadows fell on GTK+’s lap.

During the web engines hackfest, a couple of months ago, I delved deeper into the problem and noticed, with Carlos Garcia’s help, that it was even worse when HiDPI displays were thrown into the mix. The scaling made things unbearably slower.

You might also be wondering why would painting of window decorations be such a problem, anyway? They should only be repainted when a window changes size or state anyway, which should be pretty rare, right? Right, that is one of the reasons why we had to make it fast, though: the resizing experience was pretty terrible. But we’ll get back to that later.

So I dug into that, made a few tries at understanding the issue and came up with a patch showing how applying the blur was being way too expensive. After a bit of discussion with our own Pekka Paalanen and Benjamin Otte we found the root cause: a fast path was not being hit by pixman due to the difference in scale factors on the shadow mask and the target surface. We made the shadow mask scale the same as the surface’s and voilà, sane performance.

I keep talking about this being a performance problem, but how bad was it? In the following video you can see how huge the impact in performance of this problem was on my very recent laptop with a HiDPI display. The video starts with an Epiphany window running with a patched GTK+ showing a nice demo the WebKit folks cooked for CSS animations and 3D transforms.

After a few seconds I quickly alt-tab to the version running with unpatched GTK+ – I made the window the exact size and position of the other one, so that it is under the same conditions and the difference can be seen more easily. It is massive.

Yes, all of that slow down was caused by repainting window shadows! OK, so that solved the problem for HiDPI displays, made resizing saner, great! But why is GTK+ repainting the window even if only the contents are changing, anyway? Well, that turned out to be an off-by-one bug in the code that checks whether the invalidated area includes part of the window decorations.

If the area being changed spanned the whole window width, say, it would always cause the shadows to be repainted. By fixing that, we now avoid all of the shadow drawing code when we are running full-window animations such as the CSS poster circle or gtk3-demo’s pixbufs demo.

As you can see in the video below, the gtk3-demo running with the patched GTK+ (the one on the right) is using a lot less CPU and has smoother animation than the one running with the unpatched GTK+ (left).

Pretty much all of the overhead caused by window decorations is gone in the patched version. It is still using quite a bit of CPU to animate those pixbufs, though, so some work still remains. Also, the overhead added to integrate cairo and GL rendering in GTK+ is pretty significant in the WebKitGTK+ CSS animation case. Hopefully that’ll get much better from GTK+ 4 onwards.

Gustavo Noronha (kov): Web Engines Hackfest 2016!

5 de Outubro de 2016, 12:23, por Planeta GNOME Brasil - 0sem comentários ainda

I had a great time last week and the web engines hackfest! It was the 7th web hackfest hosted by Igalia and the 7th hackfest I attended. I’m almost a local Galician already. Brazilian Portuguese being so close to Galician certainly helps! Collabora co-sponsored the event and it was great that two colleagues of mine managed to join me in attendance.

It had great talks that will eventually end up in videos uploaded to the web site. We were amazed at the progress being made to Servo, including some performance results that blew our minds. We also discussed the next steps for WebKitGTK+, WebKit for Wayland (or WPE), our own Clutter wrapper to WebKitGTK+ which is used for the Apertis project, and much more.

Zan giving his talk on WPE (former WebKitForWayland)Zan giving his talk on WPE (former WebKitForWayland)

One thing that drew my attention was how many Dell laptops there were. Many collaborans (myself included) and igalians are now using Dells, it seems. Sure, there were thinkpads and macbooks, but there was plenty of inspirons and xpses as well. It’s interesting how the brand make up shifted over the years since 2009, when the hackfest could easily be mistaken with a thinkpad shop.

Back to the actual hackfest: with the recent release of Gnome 3.22 (and Fedora 25 nearing release), my main focus was on dealing with some regressions suffered by users experienced after a change that made putting the final rendering composited by the nested Wayland compositor we have inside WebKitGTK+ to the GTK+ widget so it is shown on the screen.

One of the main problems people reported was applications that use WebKitGTK+ not showing anything where the content was supposed to appear. It turns out the problem was caused by GTK+ not being able to create a GL context. If the system was simply not able to use GL there would be no problem: WebKit would then just disable accelerated compositing and things would work, albeit slower.

The problem was WebKit being able to use an older GL version than the minimum required by GTK+. We fixed it by testing that GTK+ is able to create GL contexts before using the fast path, falling back to the slow glReadPixels codepath if not. This way we keep accelerated compositing working inside WebKit, which gives us nice 3D transforms and less repainting, but take the performance hit in the final “blit”.

Introducing "WebKitClutterGTK+"Introducing “WebKitClutterGTK+”

Another issue we hit was GTK+ not properly updating its knowledge of the window’s opaque region when painting a frame with GL, which led to some really interesting issues like a shadow appearing when you tried to shrink the window. There was also an issue where the window would not use all of the screen when fullscreen which was likely related. Both were fixed.

André Magalhães also worked on a couple of patches we wrote for customer projects and are now pushing upstream. One enables the use of more than one frontend to connect to a remote web inspector server at once. This can be used to, for instance, show the regular web inspector on a browser window and also use IDE integration for setting breakpoints and so on.

The other patch was cooked by Philip Withnall and helped us deal with some performance bottlenecks we were hitting. It improves the performance of painting scroll bars. WebKitGTK+ does its own painting of scrollbars (we do not use the GTK+ widgets for various reasons). It turns out painting scrollbars can be quite a hit when the page is being scrolled fast, if not done efficiently.

Emanuele Aina had a great time learning more about meson to figure out a build issue we had when a more recent GStreamer was added to our jhbuild environment. He came out of the experience rather sane, which makes me think meson might indeed be much better than autotools.

Igalia 15 years cakeIgalia 15 years cake

It was a great hackfest, great seeing everyone face to face. We were happy to celebrate Igalia’s 15 years with them. Hope to see everyone again next year =)

Jonh Wendell: Festa de lançamento do GNOME – Sucesso! Hands on em breve?

3 de Outubro de 2016, 14:06, por Planeta GNOME Brasil - 0sem comentários ainda

Aê gente! Passada rápida aqui só pra dizer que foi muito bacana a nossa festinha do GNOME.

Tivemos 2 palestras “informais” e muito, mas muito bate papo acerca do GNOME: tecnologia, comunidade, meritocracia, GNU e FSF e afins 🙂

O Georges escreveu sobre a festa em inglês, quem puder dá uma olhada lá.

No final ficou um sentimento que seria bacana termos um próximo encontro com hands-on, mais hacking e menos talk 🙂 Achei bacana a ideia e criei um meetup pra isso. Se tivermos gente interessada o suficiente podemos fazer. O que acham? Divulguem!

Gustavo Noronha (kov): WebKitGTK+ 2.14 and the Web Engines Hackfest

22 de Setembro de 2016, 17:03, por Planeta GNOME Brasil - 0sem comentários ainda

Next week our friends at Igalia will be hosting this year’s Web Engines Hackfest. Collabora will be there! We are gold sponsors, and have three developers attending. It will also be an opportunity to celebrate Igalia’s 15th birthday \o/. Looking forward to meet you there! =)

Carlos Garcia has recently released WebKitGTK+ 2.14, the latest stable release. This is a great release that brings a lot of improvements and works much better on Wayland, which is becoming mature enough to be used by default. In particular, it fixes the clipboard, which was one of the main missing features, thanks to Carlos Garnacho! We have also been able to contribute a bit to this release =)

One of the biggest changes this cycle is the threaded compositor, which was implemented by Igalia’s Gwang Yoon Hwang. This work improves performance by not stalling other web engine features while compositing. Earlier this year we contributed fixes to make the threaded compositor work with the web inspector and fixed elements, helping with the goal of enabling it by default for this release.

Wayland was also lacking an accelerated compositing implementation. There was a patch to add a nested Wayland compositor to the UIProcess, with the WebProcesses connecting to it as Wayland clients to share the final rendering so that it can be shown to screen. It was not ready though and there were questions as to whether that was the way to go and alternative proposals were floating around on how to best implement it.

At last year’s hackfest we had discussions about what the best path for that would be where collaborans Emanuele Aina and Daniel Stone (proxied by Emanuele) contributed quite a bit on figuring out how to implement it in a way that was both efficient and platform agnostic.

We later picked up the old patchset, rebased on the then-current master and made it run efficiently as proof of concept for the Apertis project on an i.MX6 board. This was done using the fancy GL support that landed in GTK+ in the meantime, with some API additions and shortcuts to sidestep performance issues. The work was sponsored by Robert Bosch Car Multimedia.

Igalia managed to improve and land a very well designed patch that implements the nested compositor, though it was still not as efficient as it could be, as it was using glReadPixels to get the final rendering of the page to the GTK+ widget through cairo. I have improved that code by ensuring we do not waste memory when using HiDPI.

As part of our proof of concept investigation, we got this WebGL car visualizer running quite well on our sabrelite imx6 boards. Some of it went into the upstream patches or proposals mentioned below, but we have a bunch of potential improvements still in store that we hope to turn into upstreamable patches and advance during next week’s hackfest.

One of the improvements that already landed was an alternate code path that leverages GTK+’s recent GL super powers to render using gdk_cairo_draw_from_gl(), avoiding the expensive copying of pixels from the GPU to the CPU and making it go faster. That improvement exposed a weird bug in GTK+ that causes a black patch to appear when shrinking the window, which I have a tentative fix for.

We originally proposed to add a new gdk_cairo_draw_from_egl() to use an EGLImage instead of a GL texture or renderbuffer. On our proof of concept we noticed it is even more efficient than the texturing currently used by GTK+, and could give us even better performance for WebKitGTK+. Emanuele Bassi thinks it might be better to add EGLImage as another code branch inside from_gl() though, so we will look into that.

Another very interesting igalian addition to this release is support for the MemoryPressureHandler even on systems with no cgroups set up. The memory pressure handler is a WebKit feature which flushes caches and frees resources that are not being used when the operating system notifies it memory is scarce.

We worked with the Raspberry Pi Foundation to add support for that feature to the Raspberry Pi browser and contributed it upstream back in 2014, when Collabora was trying to squeeze as much as possible from the hardware. We had to add a cgroups setup to wrap Epiphany in, back then, so that it would actually benefit from the feature.

With this improvement, it will benefit even without the custom cgroups setups as well, by having the UIProcess monitor memory usage and notify each WebProcess when memory is tight.

Some of these improvements were achieved by developers getting together at the Web Engines Hackfest last year and laying out the ground work or ideas that ended up in the code base. I look forward to another great few days of hackfest next week! See you there o/

Jonh Wendell: Festa de lançamento do GNOME 3.22 – Confirmada

22 de Setembro de 2016, 16:49, por Planeta GNOME Brasil - 0sem comentários ainda

Teremos festinha do GNOME em São Paulo!

Data: 01/10/2016 (Sábado) – 10h
Local: Red Hat Brasil – Av. Faria Lima, 3900 – 8º Andar. Mapa.

Como dito no post anterior a ideia é ser um evento informal, com algumas palestras e muito bate-papo. Quem quiser palestrar, acesse esse documento do Google Docs e adiciona seu nome lá. O importante é ser algo relacionado ao GNOME né 🙂

Quanto aos comes e bebes, acredito que podemos seguir o mesmo modelo colaborativo, né? Ou seja a gente mesmo leva os salgados, doces, refri, etc. O que vocês acham? Coloquem lá nesse mesmo documento o que vocês pretendem levar.

Temos um limite de vagas e, além disso precisamos do nome e RG de todos que comparecerão. Isso é pra controle de acesso ao prédio. Portanto, enviem para o e-mail seu nome e RG para que possamos confirmar sua vinda e autorizar a entrada de vocês.

Ansioso pra encontrar essa galera! Abraços e até lá!

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