Qt GUI Toolkit Ported to JavaScript via Emscripten

http://badassjs.com/post/43158184752/qt-gui-toolkit-ported-to-javascript-via-emscripten

by adamnemecek • 13 years ago

106 40 13 years ago

eksith• 13 years ago

Good news for browser centric thin clients/devices, I suppose. There was a lot of criticism of devices, particularly Chromebook, that rely on the cloud; that you're fairly limited by what you can reach via the browser. Well, it looks like you can reach a lot more now.

I hope we can look forward to getting rid of pointless apps that are forced on you just to read a web page though. That's really, really annoying.

Wilya• 13 years ago

I'm not sure whether I should be impressed, consterned or scared.

It's the sort of things I would love as a developer (Hey ! Portability! Less code to write ! awesome mature toolkits !) and I would never want as an user ( Hey ! It's the same as old Qt apps, except five time slower !).

adamnemecek2• 13 years ago

From the comments: "From Qt came KDE, KDE produced KHTML which became WebKit which I can now use to render Qt. Full circle indeed!"

eyko2• 13 years ago

Just that KJS -> JavascriptCore. Is that understood as part of KHTML/WebKit?

kombine3• 13 years ago

Well, this is no more than a showcase. On my fairly modern computer with powerful graphics card it is unbearably slow even in Chrome, while remember, Qt used to run on embedded devices with no hardware acceleration whatsoever . Everyone and her granma is excited about web technologies, but this is not the future I want.

Native Client approach is a lot more promising, despite not being welcomed well in the industry.

rtpg2• 13 years ago

it might be more of a canvas issue than anything. emscripten gets some good results most of the time (something like 10x speed down compared to g++ -O3).

Canvas (and webGL notably) support is there, but its super flaky and hard to make fast.

kombine3• 13 years ago

And at which point in history 10x speed down has become acceptable? In certain industries people are trying to squeeze the last bit of performance out of their code, fine tuning cache usage, SSE and whatnot. I just don't see it as an innovation in technologies, quite the opposite in fact.

azakai4• 13 years ago

This is just a proof of concept. It uses the raster renderer, for example. Also the code isn't fully optimized.

Not necessarily saying this approach (Qt to JS) is the way for GUI apps, but this + hardware accelerated rendering could be interesting.

pjmlp2• 13 years ago

Why on earth would I want to use this?!

vetrom• 13 years ago

Porting 'legacy' QT apps with too much functionality in the QT bits to a browser hosted environment could, I imagine, form a case in favor of simplifying software delivery. (That, or forcing a desktop upgrade to i7's. Think of the kickback opportunities!)

ori_b• 13 years ago

I'd rather just ship a Qemu image. Or have OSes handle sandboxing properly, and make it possible to run native apps off the web directly.

jrogers65• 13 years ago

Because you can write web applications without having to use crippled, half baked JS frameworks. GUI programming was solved over a decade ago. The things we do in the browser these days, in terms of complicated web apps, mostly consist of reinventing the wheel. Backbone, ember, knockout, etc are all toys with missing wheels in comparison to a serious GUI toolkit. In contrast, Qt is well tested, very well designed and elegant. It's been around since 1992 - 21 years old!

pjmlp2• 13 years ago

I will take the desktop over the web any day for complex applications.

My experience in web development projects makes me every day more convinced that the only thing the browser is good for, is documents.

curiousdannii• 13 years ago

I really hope this includes QtWebKit!

BonoboBoner• 13 years ago

i heard you like browsers...

eyko2• 13 years ago

... so i put a browser in your browser so you can browse while you browse.

10098• 13 years ago

No, thanks. I'm already frustrated by all the crappy "native" (non-ported) javascript applications that never work as expected, so let's not keep adding to this.

shadowmint2• 13 years ago

Cute idea; compile C++ -> LLVM -> Javascript.

...but the problem is that relatively few business GUI applications do nothing. The front end has no purpose other than to trigger some kind of backend action, or update some database, or read some data from some source and display it.

...and that backend, non-QT code, which talks to system libraries, is never ever ever going to compile to javascript.

So other than tech-demo, what's the use case for this?

adamnemecek2• 13 years ago

Say no more, say no more! There is just the thing for you:

http://www.webtoolkit.eu/wt

To answer your question, I'm not sure what is the use for this, since you know, it does not compile to coffeescript /sarcasm. But in all seriousness, I did not post this to advocate it's use, but because I found it somewhat strange.

shadowmint2• 13 years ago

What on earth are you talking about?

I'm not dissing this project; I think the c++ to javascript compiler is really neat.

I just don't think I've ever seen any real QT applications that would compile and run with it; they all talk to databases or system services, which isn't supported.

regularfry• 13 years ago

What a wonderful, pointless, hilarious, inpiring hack.

MatthewPhillips2• 13 years ago

Are there any projects using emscripten that aren't just demos?

dbaupp• 13 years ago

Empythoned, the Python interpreter used by http://reply.it/

azakai4• 13 years ago

In practical terms, most of the publicly available stuff is demos. It's easy to create demos of open source projects and publish them immediately.

It takes longer for commercial codebases to be ported, pass all the stages of productization, and be officially launched. My prediction is for a few such projects to show up later this year.

With that said, there are some uses of emscripten that are not demos. For example emscripten was used to port the crunch decoder to JS in gl-matrix, and that might well be used in non-demos. Also there are educational sites using compiled languages like repl.it as another commenter mentioned. I've also seen a few other practical uses, e.g. of sql.js in sqlfiddle.

MatthewPhillips2• 13 years ago

It doesn't have to be commercial to be more than a demo. Sql.js was a great concept but hasn't been updated in 10 months (unless there is a fork that is maintaining it), even though it has major issues.

I know you Mozilla guys don't have time to maintain ports, but are you doing anything to encourage open source devs to actually use and maintain this stuff? I'm working on an emscripten port of a game myself that I do want to actually maintain and improve upon, but I get the impression that I am in the minority.

przemoc• 13 years ago

"it’s actually really fast and responsive"

Is everyone today equipped with at least 4-core 3GHz i7s or what?

Text Edit demo is barely responsive on my Athlon 64 X2 4600+ in recent Google Chrome beta (25.0.1364.84) on up-to-date debian wheezy. To the point it's unusable, unfortunately.

I admire the project, it must have been a great fun to build it and it is impressive achievement. Really!

I still hope it may be optimized more, so it will be truly responsive. Even then it doesn't mean it's the right way to go. Web developers, please, do not write your websites as Qt apps to compile them later with emscripten-qt!

stuffihavemade• 13 years ago

I have a 4 core 2GHZ i7, and it locks up Firefox for me as well.

azakai4• 13 years ago

It is not optimized at all yet - still using software rendering in pure JS. Will be more interesting with hardware acceleration, I intend to work on that with the author of these ports.

devongovett• 13 years ago

Interesting. I did find it pretty fast or I wouldn't have written that. I was using Chrome 24 on Mac OS X 10.8 on a 2010 i5 MacBook Pro, so my computer is definitely not the latest and greatest. I guess there must be some difference between the rendering engine on the Mac and on Linux, but I don't know enough to say what.

sp332• 13 years ago

I've got a 2.8GHz AMD proc running Windows 7. Even Firefox was able to keep up with just a bit of lag, and Chrome was nice and quick.

joezydeco• 13 years ago

I'm curious how this would run inside an Android webview. Anyone have some hardware to try it out?

fosap• 13 years ago

I'd love to see a (either ported or native) Unix in javascript that can run all these ported programms. I know emscripten already does have a filesystem and stuff. But I mean something bigger, something with filesystem backends for webdav and local storage, a shell, process management and all the usual stuff. I'd be a victory over the walled garden, because today everything speaks javascript.

hemancuso• 13 years ago

I was kind of hoping it could run a Qt Webkit demo!

Qt GUI Toolkit Ported to JavaScript via Emscripten

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