[Symbian] screen flickering and app crashing [SOLVED]

[Nathan W]

Hi all,

In the past we had this problem too and solved it by executing the IwGxInit() and IwGLInit() functions. Since we experienced a lot of trouble with graphics in mixed ShiVa and Marmalade apps, we decided to do all graphics in ShiVa and to remove any Marmalade graphics code. So now we don't have IwGx and IwGL anymore.

We now only use the Marmalade code to run our ad engine, which interacts with our ad servers. So we still need Marmalade in our apps.

But now the problem with a flickering screen and the crashing app returned, on Symbian only. After about a minute, the screen starts flickering and finally the app crashes.

Any idea what could cause this problem? Or should we perform an explicit initialisation of GL in ShiVa?

Thanks,
Nathan

[Nitim]

Here is a video of the problem in addition to Nathans post:
http://youtu.be/a5N8NA8YGds

[Nathan W]

Additional info:

At the startup of the app, the splash screen is shown 'forever'. However, if I go to the device its main menu and then return to the app, the app it's first screen is displayed.

Also, if the splash screen is displayed and I touch the screen on the location where a button is expected in the app it's first screen, it is pressed.

Scenario:

- The splash screen is shown, I touch the screen at the location where button X is located in the app it's first screen.
- I go to the device its main meny and then return to the app.
- The menu that should be activated when pressing button X is shown. So it seems the app detected a button press.

Is there something we're required to do with relation to initialisation of the graphics system on the Symbian platform?

[dreamora]

Problems with rendering like these likely would best be asked on the marmelade boards as I'm sure that they know better under which circumstances marmelade would fail to render on Symbians and especially fail with such a flickering.
As all the rendering is done through Marmelade (shiva doesn't render anything anymore it only executes the IwGx and GL commands for marmelade to execute) they are pretty surely better at guessing potential roots.

In general the strange form of failing looks like either being a problem with the graphics memory (-> or whole system memory being overflooded due to the low amount present hence it has backbuffer problems or is not even able to load textures properly anymore like the one after your start screen) or that the graphics context itself is failing / trying to go to sleep. Last time I saw such a failure was when my 3DFx card burnt its VRAM to crisp over a decade ago

[Nathan W]

It took a couple of days, but we finally solved the problem. I already suspected that the problem was in the initialisation procedure of either IwGx or IwGL and today I read a bit on the principle of selective linking. It seems possible to initialise parts of IwGx only.

I'm still not sure why the problem occurs on Symbian only, but we solved the problem by calling the functions below prior to initialising ShiVa.

Code: Select all

IwGxInit_Base();
IwGxInit_GLRender();