About Qtopia on PPC

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Guninia

Beginner

Posts: 5

Location: Taiwan

Occupation: software engineer

Thursday, January 17th 2008, 8:07am

About Qtopia on PPC

Dear all,

I'm trying to write a GUI program for Power PC with 300e CPU and PCI graphic card on it.
I wrote it on x86 Linux system and cross-compiled it.
When it running in Linux on Power PC, everything is fine except the colors.
It seems the endian problems because I have done some tests for the framebuffer with different endian.
The x86 system is little-endian and Power PC is just the opposite,
so there might be something wrong when processing the RGB values.

I tried to re-configure the Qtopia with "-big-endian" when cross-compile, but it didn't work.

I wonder if it works or not by modifying "qscreen_qws.h".

Please give me some suggestion to solve this problem, thanks.

New Qt programmer

Guninia

Beginner

Posts: 5

Location: Taiwan

Occupation: software engineer

Wednesday, January 23rd 2008, 8:44am

Is there anybody tried running Qtopia progams on PPC?
Is there anyway to change the color byte order from argb to gbra for Qtopia GUI programs?
The endian settings for Qtopia seems affecting only data except the GUI image colors.

I use the style sheet to design the looking for the GUI, and it seems useless to change the QRgb definition.
What function will the style sheet call to implement the style sheet syntax?

I wonder that my questions are too easy, and no one would answer, hehe...
Actually I'm newbie for Qt and embedded programming.
Thanks for your help anyway.

New Qt programmer

nijish

Trainee

Posts: 154

Location: Bangalore

Occupation: Software Engineer

Sunday, February 17th 2008, 9:42pm

is it color distortion? if it is then check your color palette and re-configure.

if your display is showing 'stripes' then it ideally means that you have a endian problem. but qt does provide a solution for this problem in its raster file. enabling the flag will do.
and, if this doesnt work, write a macro in the driver file to change rgb to bga....

Guninia

Beginner

Posts: 5

Location: Taiwan

Occupation: software engineer

Thursday, February 21st 2008, 4:22am

Thanks for your reply.

I've tried the ENDIAN flag while configuring, but it seems useless.

I'm contacting the video card menufacturer to discuss about the offset problem.

New Qt programmer

nijish

Trainee

Posts: 154

Location: Bangalore

Occupation: Software Engineer

Thursday, February 21st 2008, 7:45pm

hmm... i meant playing around with flags like:

>>> QT_QWS_REVERSE_BYTE_ENDIANNESS,
>>> QWS_BIG_ENDIAN,
>>> QT_QWS_EXPERIMENTAL_REVERSE_BIT_ENDIANNESS,
etc...

they might just work for you.

anyways, let know what is the problem.

nijish

Trainee

Posts: 154

Location: Bangalore

Occupation: Software Engineer

Thursday, February 21st 2008, 7:46pm

btw... what is the spec of your screen?

Guninia

Beginner

Posts: 5

Location: Taiwan

Occupation: software engineer

Friday, February 22nd 2008, 7:12am

My Screen is Samsung SyncMaster 750s, CRT.

Is there anything I should pay attention about screen?

New Qt programmer

nijish

Trainee

Posts: 154

Location: Bangalore

Occupation: Software Engineer

Friday, February 22nd 2008, 7:54am

depends.. i will have to check out the specs to tell you more.

i had used a 640x240 resolution screen. hence i had to set width and height in driver(qgfxlinuxfb) file. since you are using linux, you wouldnt need the baseaddress of the panel.

also, the palette would generally be different. i mean, it is always good to have a conversion algorithm for rgb to bgr. you can ignore alpha channel for the initial setup till you see something on the screen. alpha blending can be taken up later is what i believe.