[Interest] Compilation issue for OpenGL ES2 on ARM/Linux

[Thomas Senyk]

On Tue, April 16, 2013 07:47:32 AM Andre Renaud wrote:
> Hi Thomas,
> I don't think it's a problem with egl.h itself. The problem seems
> actually to be that for some reason QT_NO_EGL is getting defined,
> meaning that when egl/qegl_p.h is #include'd, it ends up only defining
> a few of the EGL options (and noy including GLES2/gl2.h). The problem
> I have is I cannot work out where QT_NO_EGL is getting defined, or
> what has caused it.

Ah sorry you mentioned that in your first mail! You're right! :)

You're building on linux, for linux, right?
The only settings I found were win(ce) or symbian related.

(and tools/configure/configureapp.cpp .. but that's only used on windows 
(maybe mac?) ... not sure, haven't used either of those for a while ;)

To pin-point the case I recommend: grep -r QT_NO_EGL and then either qmake -d 
(debug) .. or which might be faster: adding 'message("foo")' to all .pro and 
pri where QT_NO_EGL is presents

> 
> Is it possible that it's picking things up from my native QT build?
> I'm cross building on an ubuntu machine.

You should see warnings about this ... 'It's unsafe to include /... in cross-
build' or something like that.


One thing you might find useful to try is to build for qpa instead of qws.
  (it's -qpa instead of -embedded)
It's similar, the difference is that with qpa you don't get a built-in window-
system ... which means without a external windowing-system (x11, wayland, 
dfb,...) you can only get one full-screen surface (and therefor single 
process, single window).

If this is sufficient for you, maybe qpa is simpler so solve.
.. on the other hand, multi-window opengl never worked very well (/on a lot of 
setups) in qws neither, so not much lost :D




> 
> Regards,
> Andre
> 
> On 15 April 2013 23:09, Thomas Senyk <thomas.senyk at pelagicore.com> wrote:
> > On Mon, April 15, 2013 09:44:29 AM Andre Renaud wrote:
> >> Hi Thomas,
> >> 
> >> > What does configure tell you? ... configure with -egl to enforce it.
> >> > (if you post the configure output, always add -v (verbose) to
> >> > configure)
> >> 
> >> I'm not entirely sure which bit of the configure output you're after
> >> there. I've added the -egl flag, but it doesn't seem to make any
> >> difference. Attached is the (compressed - it ran to > 1MB) output from
> >> configure.
> >> 
> >> Any ideas/comments?
> > 
> > Hmm this is strange. The configure test is successful .. so it can find
> > egl.h and libegl ... also after taking another look at the error...
> > 
> >   it seems to find egl.h, but not much of it's symbols/defines.
> > 
> > You need to check what's going on with your egl.h ... are those symbols
> > missing (broken egl.h) .. are they defined somewhere else (also broken
> > egl.h)> 
> >  ... are they disabled due to some defines (e.g. some platforms require
> > 
> > defines to select the egl platform)
> > '
> > 
> >> Regards,
> >> Andre