unsigned shorts in Photon widgets

QNX DEVELOPERS GUI Programming
1

Hello,
I’m making a GUI app which displays a very large canvas inside a PtScrollContainer, however when the canvas gets really huge, odd things start to happen. It would seem that this is down to the height of the canvas being larger than 65535, the limit for an unsigned short, which is the type of number that seems to be required for resizing Photon widgets.

I’m guessing I’m not the first person to need a widget larger than this, anyone know what the workaround is?

Thanks a lot

Garry

PS. One more thing, is there an official channel at QSS for reporting bugs/problems, rather than swamp forums like this one?

2

Yes, you can report problems on the newsgroups (you can post via myqnx.com if you don’t have a newsreader). There used to be a “report a bug” link on qnx.com, don’t know if that one is still present tho…)

Not sure about a good workaround, i’ll think about it =)

3

Thanks phearbear, I’ll wait before posting this as a bug, though. After some debugging, looks like my canvas goes way past 65535, over 250,000 in fact, so I’ll definitley need to sort something out!

Cheers

Garry

4

PhDim_t element are all unsigned short. My guess is Photon cannot handle Widgets bigger then 65535x65535 element.

5

That’s what I thought, I just did not want to believe it :imp:

So I guess the key is to not use PtScrollContainer (which by happy co-incidence might alleviate some of the bugs in PtOSContainer) and move stuff around myself, using long ints to store their actual position and move them around the canvas relative to a seperate scrollbar.

Cheers

Garry

6

I think it’s a reasonable limit for graphics element. But for printer this is going to be a problem in few years. With today’s printer reaching 6000DPI it will be soon impossible to print full resolution (if my understanding of how Photon handles printing is right)

7

Beware of the PtOSContainer, it somehow seem to crap out everytime I use it… definatly with the Scrollcontainer… (which I don’t really like either…)

8

Yes, I have had many problems with the PtOSContainer, it seems to be pretty buggy, but maybe that’s down to me using an unsupported video card. I have found the ScrollContainer fine, except the max dimensions of a widget, which are not big enough for me so I could not use it if I wanted to :frowning:

I’m going to persevere with the PtOSContainer, as my app is really flickery without it.