Log from #neuros IRC channel

<crweb>

sorry, Visualization

<crweb>

demonstrate

<crweb>

how the Qt� application development framework, together with the advanced

<crweb>

Coin3D graphics toolkit from SIM, provide one of the best 3D visualization

<crweb>

solutions for developing advanced applications in the Oil & Gas industry.

[12:34]

crweb: cool hardware prize, for attending a webcast ?

<crweb>

yeah, last time it was a pda

<crweb>

really nice one, that uses qt

<crweb>

cant remember what it was called though

to every webcast attendee ?

<crweb>

no

<crweb>

just one

ah, i see

<crweb>

but there aren't many attending

yeah, but my luck is what it is ;)

[12:36]

<crweb>

all you have to do is dial into the toll free number, go walk around the house with the phone for 40 minutes, and listen to who wins at the end :)

[12:36]

excepti it won't be toll free for me

[12:38]

<crweb>

they have international tollfree numbers

[12:38]

<crweb>

trolltech isn't a US company

[12:38]

aren't they somewhere from northern europe ?

[12:39]

<crweb>

Oslo Norway

[12:39]

<crweb>

but they have very many different #'s

[12:39]

<crweb>

just for the webnairs

<crweb>

Munich, Berlin, Brisbane, Beijing, USA, and Oslo Norway

<crweb>

are the local offices

they're getting pretty big

<crweb>

webcasts aren't actually given by trolltech though

[12:42]

affiliates, i've seen that

[12:49]

<unknown_lamer>

I lust after the greenphone

[12:50]

what is a greenphone ?

[12:50]

<unknown_lamer>

the qtopia phone edition dev platform

<unknown_lamer>

seems great

does anyone have an idea why one would want to wrote something like do { printf("message"); }while(0) ,instead of just doing the printf ?

[13:38]

nerochiaro: Off the top of my head, no, although I almost think that it *can* be useful sometimes... for some reason...

[13:39]

it just doesn't make much sense to me, unless maybe to try to force the compile to not do some kind of optimization.

[13:39]

or some dirty trick likethat

[13:54]

Qt tutorial?

[13:54]

Where do I sign up? :D

[13:55]

AsGF2MX: the one crweb posted is not a tutorial, it seems like a demonstration on some uses of Qt for visualizations in software

[13:55]

Hmm

[13:56]

I have no experience with Qt but I'd like to have a look if it isn't too complicated

[13:56]

Or is the web-seminar a little too advanced?

[13:58]

i dunno, probably the second you said though. crweb is the qt man around here, though ;)

[13:59]

I saw some of his screenshots and I watched the videos. Though the OSD doesn't seem to have enough RAM for him to put on a proper Qt UI :P

[14:00]

what do you mean with "proper" ?

[14:03]

Err

[14:03]

I'm under the impression he's trying to do a full out replacement UI

<crweb>

theres enough ram

<crweb>

it runs perfectly fine

<crweb>

even with an sqlite backend

I recall you mention something being harder...

<crweb>

harder than C and ncooler? def not

Hmm

<crweb>

taking ncooler out of the media libs, yes

crweb: ncooler ain't hard, come on

ncooler?

C ... no problem

What's ncooler?

the neuros widget toolkit

Oh

<crweb>

well in comparison to qt

crweb: problem with cooler is that it's too quirky

<crweb>

i have my gui running on my desktop

<crweb>

dont' have to compile to see it

<crweb>

err, don't have to run it on osd to see it

yeah, that's handy, but not fundamental.

Screenshots?

<crweb>

www.limesg.com some are on pc, some are on osd

I was actually wondering the other day when JoeBorn asked if I was a UI guy

AsGF2MX: what were you wondering

?

crweb: I saw those pics in the ftp site

<crweb>

nerochiaro: i've got webkit working, which is khtml web browser

nerochiaro: well whether I can do UI things or not...the only thing I might like to help with is the topology of the menu

crweb: that is handy

<crweb>

nerochiaro: no user input for it yet though. so kinda useless, but is a nice browser for the osd

oh and the input method but I am no pro there...

crweb: works fast enough that browser ?

<crweb>

yeah

cool. gets input only via mouse i imagine ?

crweb: With a browser functionality, it would be great but it's troublesome to navigate with a remote

<crweb>

wont be any more troublesome than mobile phone

<crweb>

nerochiaro: it can, but no, it uses nermical keypad

<crweb>

i just havent linked ityet

Hmm

nermical ?

<crweb>

T9

<crweb>

numerical

<crweb>

heh

Typing address is fine but what about clicking page elements?

crweb: ah, ok

<crweb>

AsGF2MX: never used your keyboard instead of amouse?

I have

<crweb>

same thing

kinda painful in fact

<crweb>

qtdeveloper.net

But no tab key on the remote...

looking

<crweb>

so?

<crweb>

it has to have "tab" written on it ? ;)

AsGF2MX: you can use any other key as tab. even one arrow

Well, you need some way to go through the elements...I called it "tab" just for the sake of it ;)

<crweb>

there are 37 keys

Yep

AsGF2MX: what about left and right arrow to move around elements. pefect

up down to scrol

How will you deal with frames?

<crweb>

the same way mobile browsers do

<crweb>

there is nothing new here

[14:13]

<crweb>

I took a phone mobile browser, and compiled with qtopia and our toolchain

[14:13]

To be honest, I'm using an XDA Mini S with IE and a keyboard and stylus make it easy. I never tried to browse the web on my T720 prior to this.

<crweb>

usb hub and mouse plugged into the osd will solve any "issues"

*PIE as FF is too much of a resource hog...I really should have a look at a normal phone

<crweb>

Opera

<crweb>

and waht is *PIE as FF ?

[14:15]

*as should be and ... PIE = Pocket IE , FF = FireFox

[14:15]

<crweb>

ah

[14:15]

<crweb>

brb, time for the monthly reboot

<crweb>

( /dev/hdb1 is stuck as mounted, but can't find where )

Also USB hubs, I thought the port on the OSD is USB1.1? I'm just thinking if using a keyboard will hog the bandwidth

can't find where?

<crweb>

keyboard, hog 1.1 bandwidth?

no, a keyboard is really low low bandwidth

No no...you have too many devices

<crweb>

you can have up to 127 devices

Does that apply to USB1.1 and 2?

<crweb>

umm.. yes

<crweb>

give it a sec

it?

<crweb>

nvrmind

<crweb>

anyway, keyboard only uses bandwidth when a key is pressed

[14:18]

<crweb>

and even then, its only 2bytes per ke

[14:18]

<crweb>

key

[14:18]

I'm just wondering of a situation like this: you're playing video off a USB HD, then you have a keyboard and start typing something. Will the video stutter?

[14:19]

<crweb>

usb would have never been invented if that is how it worked

[14:19]

AsGF2MX: no way

[14:19]

AsGF2MX: think about how much information you need to get from a keyboard even at the highest typing rate you can sustain ? very very little

[14:20]

<crweb>

it would take 750000 keystrokes a second, to tak 100% bandwidth

[14:21]

<crweb>

if you type 50 words a minute, thats 4 keystrokes a second

[14:21]

True but even if you don't reach 100% saturation point, in USB, what about overheads?

<crweb>

theres no way "overhead" is more than 50% of the bandwidth

It's not the 50%

It's just in between your video stream

<crweb>

thats not how it works

?

<crweb>

they are concurrent, they both happen at the same time

<crweb>

parallel

[14:23]

<crweb>

it doesn't stop the video, and wait for the keyboard

[14:23]

But in usb you only have 2 wires which use differential signalling - serial half-duplex...correct? So in these hubs is the data being serialized?

[14:24]

<crweb>

does your usb keyboard make your usb mouse quit working?

[14:24]

<crweb>

does transfer from usb harddrive make your keyboard stop typing?

[14:24]

<crweb>

can't use your mouse while your camera dumps pictuers?

[14:25]

<crweb>

if you type 50 words per minute, that is .5% of the bandwidth

[14:25]

<crweb>

thats 11.94 Mbit a second left over for your video

Hmm

<crweb>

you can print, while you copy photo's

<crweb>

you can have everything you own on usb 1.1

<crweb>

and it still work fine

Hmm

<crweb>

i actually don't have a single device thats not usb

[14:27]

<crweb>

except for a firewire array of drives

[14:29]

Ok, thinking about it, it probably won't occur...given the way USB works...

<crweb>

Looking

<crweb>

data transfer speed != to host controller speed

[14:30]

^^^ noted

[14:30]

<crweb>

if you have a bad chipset, and your controller can't deal with the traffic, then yes you'll have problems

[14:31]

<crweb>

and HID devices, keyboards, mice, joysticks use Low Speed basic rate anyway, which is 1.5mbit

[14:31]

I don't have any problems with my USB... they all work as you've said, just the way USB works was bugging me...hold on a sec

[14:32]

<crweb>

Full Speed devices divide the USB bandwidth between them in a first-come first-served basis and it is not uncommon to run out of bandwidth with several isochronous devices. All USB Hubs support Full Speed

[14:32]

<crweb>

yes you can run it out of transfer, but you can only play 1 video on the osd.

[14:32]

<crweb>

and video's don't use all the bandwidth themselves

[14:33]

<crweb>

that would be one heck of a highquality xvid

[14:33]

I had one for testing a while back ... boy did it choke on linux...ran fine in windows :S

<crweb>

that would be a driver issue

That's despite the fact I had everything setup...have 6800Go on this laptop.

<crweb>

?

the nvidia GeForce 6800Go

<crweb>

video playback is 2d, won't matter what vid card you have

[14:35]

decoding of video also does not go to the video card

[14:35]

But you can still offload some of the decoding to the GPU using XVMc or the like?

[14:35]

<crweb>

that has nothing to do with USB

[14:36]

<crweb>

and not the type of decoding you're thinking

[14:36]

We slightly veered off topic...or at least I did, mentioned high quality video and I mentioned this...

[14:36]

Indeed, nothing to do with USB as it's just loading the data

[14:37]

Rest is up to whatever is on the otherside, in this case the Ti ??? with the ARM core inside

[14:38]

<crweb>

TMS320C54x

[14:38]

Too many numbers to remember but I will sooner or later ;)

[14:42]

"Hubs, even Hi-Speed hubs, serving a number of non-hi-speed devices, are likely to divide up a total bandwidth of 12 Mb/s for such devices, which will slow them down unless the hub has transaction translator for each port."

[14:43]

That's what bugged me so correct if I'm wrong but in the end, it also depends on the hub you use?

[14:43]

Reading the rest

[14:45]

<crweb>

you have a low speed device

[14:45]

<crweb>

bandwidth is divided amoung devices that are USING the bus

[14:45]

<crweb>

not just plugged in and idle

<crweb>

low speed is always 1.5 max

<crweb>

that leavs 10.5

Ah

<crweb>

wouldn't make any sense to have a printer plugged in and take 50% of available

<crweb>

when a hard drive could use 75%

[14:48]

I guess that would be an issue of link speed vs actual bandwidth utilized?

[14:50]

I guess I've muddled up a few things here. I got it...

[14:50]

My bad...

[14:51]

* AsGF2MX bangs head on wall as everyone stares

[14:54]

the silence is getting to me now ... : s

[15:00]

Maybe it was my empty stomach...time for dinner

[15:01]

AsGF2MX: bon appetit

[15:01]

* AsGF2MX will be back shortly.

[15:10]

crweb: pardon my ignorance of qtopia, but does it also act as a sort of window manager ?

[15:10]

<crweb>

it can yes

[15:10]

<crweb>

I'm actually implementing the desktop right now.

[15:11]

how would that work ? with a server part that runs in the background ?

[15:11]

<crweb>

and seperating my apps

[15:11]

<crweb>

yeah, you start your main application, it can either be a server, or attach to a server

[15:12]

<crweb>

my desktop will have icons that will launch apps.

[15:12]

<crweb>

the app will open knowing that the gfx server already started

[15:14]

so server is started on boot ?

[15:15]

and of course server can only handle qt windows

[15:15]

<crweb>

no, first application = server

[15:16]

<crweb>

you can encase other apps in the qt windows

[15:16]

encase ?

<crweb>

well, i don't know how they actually do it

<crweb>

but, on OpenZaurus there are a few apps that are not qt, that can be run

<crweb>

snes is the only one I can think of right now

apps can always access the fb directly, IIRC

<crweb>

not if the fb is locked by the qtopia display

crweb: they still have probably need to be compiled against qt to be able to do that

hmm...for some reason I thought direct fb access was an option on Zaurus

'lo all, BTW :)

<crweb>

maybe it is

<crweb>

like i said, i don't know how

<crweb>

but I do know that it locks the fb on the osd

JoshMalone: hey hey

hmmm

hey nero

<crweb>

or did last time i tried

<crweb>

never know, sometimes I get mixed results

crweb: locks ? like if another app wants to write to it it can't ?

if the device is busy...yeah

some device drivers can only be opened by 1 process at a time

so it keep that busy all the time ?

but not fb

at least not on the osd

<crweb>

I can't boot right now to test

<crweb>

all the outputs to the fb would fight eachother

<crweb>

wouldn't they?

yoru syscall to fopen would fail

unless there was some multiplexing layer....

not sure, now that I think about it

yes, they do fight

<crweb>

you can't have 2 trying to draw the same pixel

last one that writes will overwrite the others

<crweb>

so some pixels would be 1 app, some the other

yes

<crweb>

sounds like joy

i tried, it's pretty funky