wxlua-users Mailing List for wxLua

On 9/3/05, Eike Decker <ei...@cu...> wrote:
> Hi
> Thanks for the answer and positive feedback on a C compatible header.
> I am sorry that I haven't described the full "problem" in my last
> request, but I didn't thought it was necessary, but it seems to be more
> complicated than I thought (surprise surprise).
It always is... :(
=20
> The project I talked about is a 3D engine that can be extended by using
> lua and it looks currently quite nice
> (http://chilli.degnet.de/~e_decker/lux/index.php/Main/Screenshots -
Looks nice.
> website is under construction...). - anyhow: We are currently using GLFW
> as windowenvironment for OpenGL which replaced Glut (we want to be
> plattformindependent). Now, the idea about wx was, that we could use it
> to extend the engine with GUI elements for making editors, etc.
wxLua would be perfect for this, except for the problems...
> I have now tried out the loadlib function in lua to load the dll like thi=
s:
> luaopen =3D loadlib("wxLua.dll", "wxLua")
>=20
> unfortunately, calling luaopen in lua itself crashs the application
> somewhere deeply in the dll and I can't debug this. Meanwhile I am also
> not sure anymore if it is really possible to extend the engine this way
> since we need our own mainloop. I guess that creating a new window using
> WX makes the engine crash since GLFW did this before - but it's only a
> guess, I haven't spend too much time on this window-stuff programming...
wxLua relies on the wxWidgets main loop and I don't think that this is
avoidable because of the required notification events.
Typically you create a wxApp instance that initializes the wxWidgets
main loop. (this is a good site for the wxWidgets docs)
http://www.lpthe.jussieu.fr/~zeitlin/wxWindows/docs/wxwin_wxappoverview.htm=
l#wxappoverview
However I have seen people handle initializing the mainloop their own way, =
see
http://www.lpthe.jussieu.fr/~zeitlin/wxWindows/docs/wxwin_wxapp.html#wxappm=
ainloop
Also search for IMPLEMENT_APP_NO_MAIN on google
http://lists.wxwidgets.org/archive/wx-users/msg33172.html
"To use your own "int main()" you'll need to use the
IMPLEMENT_APP_NO_MAIN() macro and use wxEntry. On the wiki there's a
topic about using wxWidgets in DLLs which is somewhat similar to
this."
http://wiki.wxwidgets.org/wiki.pl?Creating_A_DLL_Of_An_Application
** I have never tried to use DLLs nor anything like this so I can't be
of much help, but maybe the above will get you started and give you
some ideas.
> As a possibility, we could switch from GLFW to WX - but this would cause
> much more work on this (a little bit minor) problem than we wanted to spe=
nd.
Switching over to wxWidgets is an option, it'll add a lot of features,
some useful data structures, and whatnot, but might be a lot of work.
> Any creative ideas how to solve this problem without spending too much
> work in rewriting the C core of the engine?
As as aside, I don't want to start a war here, but C++ is perfect for
GUI libs because you can encapsulate the data for a window in a class
and use inheritance to reuse code. A button for example, has fore,
back colours, size, position and of course so would a generic window,
the button just adds a member for the label.
You can always compile C w/ C++ if you do this when including headers
extern "C"
{
 #include "cheader.h"
}
I don't know much about the loss in performance of compiling C code as
C++, but what what I've seen (Great computer language shootout IIRC)
it wasn't too significant.
Good luck,
 John Labenski

Hi
Thanks for the answer and positive feedback on a C compatible header.
I am sorry that I haven't described the full "problem" in my last 
request, but I didn't thought it was necessary, but it seems to be more 
complicated than I thought (surprise surprise).
The project I talked about is a 3D engine that can be extended by using 
lua and it looks currently quite nice 
(http://chilli.degnet.de/~e_decker/lux/index.php/Main/Screenshots - 
website is under construction...). - anyhow: We are currently using GLFW 
as windowenvironment for OpenGL which replaced Glut (we want to be 
plattformindependent). Now, the idea about wx was, that we could use it 
to extend the engine with GUI elements for making editors, etc.
I have now tried out the loadlib function in lua to load the dll like this:
 luaopen = loadlib("wxLua.dll", "wxLua")
unfortunately, calling luaopen in lua itself crashs the application 
somewhere deeply in the dll and I can't debug this. Meanwhile I am also 
not sure anymore if it is really possible to extend the engine this way 
since we need our own mainloop. I guess that creating a new window using 
WX makes the engine crash since GLFW did this before - but it's only a 
guess, I haven't spend too much time on this window-stuff programming...
As a possibility, we could switch from GLFW to WX - but this would cause 
much more work on this (a little bit minor) problem than we wanted to spend.
Any creative ideas how to solve this problem without spending too much 
work in rewriting the C core of the engine?
Thanks in advance
Eike Decker

Hi,
>>* I am using windows and mingw as compiler and make throws strange
>>errormessages if I run make (making lua was no problem that way):
>>
>>process_begin: CreateProcess((null), wx-config --basename, ...) failed.
>>process_begin: CreateProcess((null), wx-config --release, ...) failed.
>> ...
> 
> 
> These are looking for the 'wx-config' scripts, is it in your path?
> They should have been created by running configure in the wxWidgets
> root dir. I have never tried mingw, but I'm assuming it would be the
> same as using gcc in linux.
that's not so easy: wx-config cannot be used with mingw.
mingw's make is like any other win32 make and thus does not understand command 
substitution as unix makes do.
which makefile did you try ?
try to go in wxLua\build\msw and type
mingw32-make -fmakefile.gcc
Francesco

On 9/2/05, Eike Decker <ei...@cu...> wrote:
> Hi there
>=20
> I would like to include wxLua in a C project as a lib, offering an easy
> and simple way to create windows, buttons and so on, without switching
> to C++.
> Using wxLua looks like a simple solution here, since the few functions
> could be easily called from C and lua could take care about all that GUI
> stuff using wxWidgets once the application starts.
wxLua should fit the bill.
Try this version, there's a "Modules" directory that's for making a
DLL. I do not know if that's what your looking for, but maybe it's a
start. See below about the current status at SourceForge.
http://www.luascript.thersgb.net/
=20
> Unfortunatly, I am encountering some problems:
>=20
> * The current header is in c++ style (although it could be easily
> converted to a C-like form)
We could add a separate header for C, wxWidgets is a C++ library and
so wxLua, which uses many wxWidgets functions, is also C++.
> * I am using windows and mingw as compiler and make throws strange
> errormessages if I run make (making lua was no problem that way):
>=20
> process_begin: CreateProcess((null), wx-config --basename, ...) failed.
> process_begin: CreateProcess((null), wx-config --release, ...) failed.
> ...
These are looking for the 'wx-config' scripts, is it in your path?
They should have been created by running configure in the wxWidgets
root dir. I have never tried mingw, but I'm assuming it would be the
same as using gcc in linux.
> I think I compiled the wxwidget library in a correct way (at least it did=
n't complain when I compiled it as DLL), but somehow I can't create a lib f=
rom wxLua.
>=20
> It would be really nice if someone knew what steps have to be done in my =
case (the website describes linux and windows using VC++). It would be even=
 better if some default libs could be downloaded for developers, including =
a C compatible header.
We'll have to wait for things to get stabilized before making a
release. Currently the CVS version on SF is broken. There are issues
with properly wrapping enums and static functions. A member is working
on completing a set of new wrappers, so fixing the current ones have
been put on hold until then. Hopefully we'll get it together soon.
Regards,
 John Labenski

Hi there
I would like to include wxLua in a C project as a lib, offering an easy 
and simple way to create windows, buttons and so on, without switching 
to C++.
Using wxLua looks like a simple solution here, since the few functions 
could be easily called from C and lua could take care about all that GUI 
stuff using wxWidgets once the application starts.
Unfortunatly, I am encountering some problems:
* The current header is in c++ style (although it could be easily 
converted to a C-like form)
* I am using windows and mingw as compiler and make throws strange 
errormessages if I run make (making lua was no problem that way):
process_begin: CreateProcess((null), wx-config --basename, ...) failed.
process_begin: CreateProcess((null), wx-config --release, ...) failed.
 ...
I think I compiled the wxwidget library in a correct way (at least it didn't complain when I compiled it as DLL), but somehow I can't create a lib from wxLua.
It would be really nice if someone knew what steps have to be done in my case (the website describes linux and windows using VC++). It would be even better if some default libs could be downloaded for developers, including a C compatible header.
Thanks in advance
Eike Decker