June 2007 - Boost-users - lists.boost.org

Re: [Boost-users] port of GameDev SDL lib in Boost?
by Christian Henning 08 Jun '07

08 Jun '07

Hi there, I think there is something wrong with the timer. Whenever I run the code ( see below ) it slows down for whatever reason. Is that a known problem? When I look at the output the frequency is certainly not 10 times a second. #include <windows.h> #include <iostream> #include <sdl.h> using namespace std; Uint32 time_elapsed( Uint32 interval, void* param ) { cout << interval << endl; return ++interval; } int main( int argc, char* argv[] ) { SDL_Init( SDL_INIT_VIDEO | SDL_INIT_TIMER ); SDL_TimerID id = SDL_AddTimer( 100, &time_elapsed, NULL ); SDL_Event event; while( SDL_PollEvent( &event ) >= 0 ) { ::Sleep( 100 ); } return 0; }

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[signal] Invoking connect with same argument a second time allowed?
by Boris 08 Jun '07

08 Jun '07

Is it allowed to call connect() with the same argument (slot) a second time (without disconnecting in between)? I've been checking the documentation at http://www.boost.org/doc/html/boost/signalN.html#id1033842-bb but couldn't find any answer. I assume it is allowed (it doesn't throw any exception et al.) but don't want to build a software based on assumptions really. ;-) Boris

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wave: preprocessing Visual C++ 2005 stl
by Ludovic Aubert 07 Jun '07

07 Jun '07

Hello boost wave users, I have written a sample program which uses boost wave and I am trying to run it on its own source code. The environnement (especially the stl) is Microsoft Visual C++ 2005. Since typically an include file like "vector" will be preprocessed many times (once for every compilation unit), I am saving all the preprocessed tokens in a map<string, map<tuple<int,int>,string> > token, so that token[path][make_tuple(line,col)] = value. Then for each path I am using a forward iterator to spit out all the values into a buffer. The major trouble I have is with the macros #define STD_BEGIN namespace std { #define STD_END } defined in the file "yvals.h" Somehow, STD_BEGIN and STD_END are replaced by blanks and I get "namespace std{}" at the end of the files instead. Looks like the line and col for these items are wrong ... I would like to know if someone has already successfully preprocessed the stl delivered with Visual C++ 2005. Thank you in advance for your reply Ludovic Aubert

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Filesystem Exception
by Surya Kiran Gullapalli 07 Jun '07

07 Jun '07

Hello all, I'm creating a directory using boost::filesystem::create_directory function. When i looked at the documentation, It said, Throws: basic_filesystem_error<Path> if Effects fails for any reason other than because the directory already exists. Now when i catch the exception like this try { boost::filesystem::create_directory (path) } catch (boost::filesystem::basic_filesystem_error <boost::filesystem::path>& e) { cout << e.what() << endl ; } e.what() returns the string boost::filesystem::create_directory. What i expect is why the create_directory failed. How can i get the string describing the problem. Thanks in advance, Surya

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Re: [Boost-users] port of GameDev SDL lib in Boost?
by Christian Henning 07 Jun '07

07 Jun '07

My current version is more or less ready to use. you can check it here: http://gil-contributions.googlecode.com/svn/trunk/gil_2/boost/gil/extension… Let me know what you think. I'm not so sure if you can put your callback timer under the boost license. Maybe somebody else knows the answer. Christian On 6/6/07, fanzhe cui <fanzhe.cui(a)goldiom.com> wrote: > Christian, > > Boost is very widely accepted and utilized by game developers, and on the > web GameDev.net there are many many articles about various boost sub lib. > But I haven't seen many discussions about SDL lib on this boost mail list > from boost users/developers. SDL is very convenient cross-platform C++ > development platform that can be used not only game developers but also by > other developers. It has easy-to-use classes of multithreads, mutex, event > queues, timer callbacks, semaphores, key board input handling, audio, video, > to name a few. Most of these functionalities are available from Boost lib. > But I haven't seen good timer callback available from Boost lib (anybody can > correct me if I am not so informed of Boost timer). > > I tried to extract the timer functions (classes) from the SDL lib into an > individual timer lib, and the work is still in progress. I am not sure other > users in the list are interested in knowing about porting SDL timer to > Boost. So if you can tell me your email of this email list, I can send you > the project file. > > What exactly I did was that I included the relevant source files from SDL > package, and compile it with testing program. I was able to get the exe file > but the project also generated a library file in addition to the exe file. I > am confused by the fact that the project generating TimerTest.lib, that I > don't want t. Rather, I wanted to link them with TimerTest not intended to. > I checked the project configuration file, and there is no setting that will > generate a library file. I think it might be set in the program source code, > but I did not find it. > > I am interested in your idea of implement SDL wrapper in boost lib. Thank > you! > > Best regards, > Fanzhe Cui > +++++++++++++++++++++++++++ > Goldiom Systems LLC > - Information and Communication Technology Provider > Email: fanzhe.cui(a)goldiom.com > Tel: 973-210-4254 > www.goldiom.com > > > -----Original Message----- > From: boost-users-bounces(a)lists.boost.org > [mailto:boost-users-bounces@lists.boost.org] On Behalf Of Christian Henning > Sent: Wednesday, June 06, 2007 10:06 AM > To: boost-users(a)lists.boost.org > Subject: Re: [Boost-users] port of GameDev SDL lib in Boost? > > Fanzhe, I have been working on a sdl wrapper for boost::gil. It lets > you draw on a canvas and react to event such as a timer event. I was > thinking of outsourcing this portion so people can use just that. The > good thing is the sdl is supporting almost the same platforms as boost > does. The bad thing probably is the license sdl is using, LGPL. > > If you want I can give you a pointer for the code. > > Christian > > On 6/6/07, fanzhe cui <fanzhe.cui(a)goldiom.com> wrote: > > Yes, I was referring to that library and more info could be found from the > > web: http://www.libsdl.org/. > > The problem with the boost timer that you mentioned is that it provides > the > > time elapsed, but not the interface like provided by SDL lib. Particularly > > the kind of timer callback function that is available in SDL lib is not > > available in Boost lit. > > > > Best regards, > > Fanzhe Cui > > > > ++++++++++++++++++++++ > > Goldiom Systems LLC > > - Information and Communication Technology Provider > > Email: fanzhe.cui(a)goldiom.com > > Tel: 973-210-4254 > > www.goldiom.com > > > > -----Original Message----- > > From: boost-users-bounces(a)lists.boost.org > > [mailto:boost-users-bounces@lists.boost.org] On Behalf Of Tarjei Knapstad > > Sent: Wednesday, June 06, 2007 4:02 AM > > To: boost-users(a)lists.boost.org > > Subject: Re: [Boost-users] port of GameDev SDL lib in Boost? > > > > On 6/6/07, fanzhe cui <fanzhe.cui(a)goldiom.com> wrote: > > > I have been using both Boost lib and GameDev SDL lib in same projects. > > Both > > > of the lib have very good platform independency. But they have some > > > functionalities overlapping each other and I would like to use only one > of > > > them. The timer lib in GameDev SDL is very easy to use and I hope such > lib > > > or functionally similar one exists in Boost lib. I had a look at boost > > > archive on previous discussion on implementing Boost timers and feel > that > > > there is still no good implementation of timer in Boost lib (correct me > if > > I > > > am wrong). Anybody in this email list had a look at GameDev timer and > have > > > considered implementing such a lib in Boost? > > > > > > > Are you referring to the Simple Direct Medialayer? > > > > http://lazyfoo.net/SDL_tutorials/lesson12/index.php > > > > What's wrong with/missing in boost::timer ? > > > > http://boost.org/libs/timer/index.html > > > > -- > > Tarjei > > _______________________________________________ > > Boost-users mailing list > > Boost-users(a)lists.boost.org > > http://lists.boost.org/mailman/listinfo.cgi/boost-users > > > > > > > > _______________________________________________ > > Boost-users mailing list > > Boost-users(a)lists.boost.org > > http://lists.boost.org/mailman/listinfo.cgi/boost-users > > > _______________________________________________ > Boost-users mailing list > Boost-users(a)lists.boost.org > http://lists.boost.org/mailman/listinfo.cgi/boost-users > > > > _______________________________________________ > Boost-users mailing list > Boost-users(a)lists.boost.org > http://lists.boost.org/mailman/listinfo.cgi/boost-users >

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Re: [Boost-users] port of GameDev SDL lib in Boost?
by Christian Henning 07 Jun '07

07 Jun '07

Fanzhe, I have been working on a sdl wrapper for boost::gil. It lets you draw on a canvas and react to event such as a timer event. I was thinking of outsourcing this portion so people can use just that. The good thing is the sdl is supporting almost the same platforms as boost does. The bad thing probably is the license sdl is using, LGPL. If you want I can give you a pointer for the code. Christian On 6/6/07, fanzhe cui <fanzhe.cui(a)goldiom.com> wrote: > Yes, I was referring to that library and more info could be found from the > web: http://www.libsdl.org/. > The problem with the boost timer that you mentioned is that it provides the > time elapsed, but not the interface like provided by SDL lib. Particularly > the kind of timer callback function that is available in SDL lib is not > available in Boost lit. > > Best regards, > Fanzhe Cui > > ++++++++++++++++++++++ > Goldiom Systems LLC > - Information and Communication Technology Provider > Email: fanzhe.cui(a)goldiom.com > Tel: 973-210-4254 > www.goldiom.com > > -----Original Message----- > From: boost-users-bounces(a)lists.boost.org > [mailto:boost-users-bounces@lists.boost.org] On Behalf Of Tarjei Knapstad > Sent: Wednesday, June 06, 2007 4:02 AM > To: boost-users(a)lists.boost.org > Subject: Re: [Boost-users] port of GameDev SDL lib in Boost? > > On 6/6/07, fanzhe cui <fanzhe.cui(a)goldiom.com> wrote: > > I have been using both Boost lib and GameDev SDL lib in same projects. > Both > > of the lib have very good platform independency. But they have some > > functionalities overlapping each other and I would like to use only one of > > them. The timer lib in GameDev SDL is very easy to use and I hope such lib > > or functionally similar one exists in Boost lib. I had a look at boost > > archive on previous discussion on implementing Boost timers and feel that > > there is still no good implementation of timer in Boost lib (correct me if > I > > am wrong). Anybody in this email list had a look at GameDev timer and have > > considered implementing such a lib in Boost? > > > > Are you referring to the Simple Direct Medialayer? > > http://lazyfoo.net/SDL_tutorials/lesson12/index.php > > What's wrong with/missing in boost::timer ? > > http://boost.org/libs/timer/index.html > > -- > Tarjei > _______________________________________________ > Boost-users mailing list > Boost-users(a)lists.boost.org > http://lists.boost.org/mailman/listinfo.cgi/boost-users > > > > _______________________________________________ > Boost-users mailing list > Boost-users(a)lists.boost.org > http://lists.boost.org/mailman/listinfo.cgi/boost-users >

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Uninitialized value p$m_value
by Paul 07 Jun '07

07 Jun '07

Hi, I'm trying to learn how to use the Boost Graph Library. Here is a very simple code example. #include <boost/graph/adjacency_list.hpp> #include <string> int main( void ) { using namespace std; using namespace boost; typedef adjacency_list< listS, vecS, directedS, // Vertex properties property< vertex_name_t, std::string >, // Edge properties property< edge_weight_t, int > > Graph; Graph graph; // Graph traits used to access graph's iterator types graph_traits< Graph >::vertex_descriptor a, b; a = add_vertex( graph ); b = add_vertex( graph ); graph_traits< Graph >::edge_descriptor ed; bool inserted; tie( ed, inserted ) = add_edge( a, b, graph ); // LINE 26 return 0; } When I compile this with g++ v4, I get on my Debian Etch system the warning for line 26: /usr/include/boost/graph/detail/adjacency_list.hpp:263: warning: 'p$m_value' is used uninitialized in this function Line 263 in adjacency_list.hpp looks as follows: inline stored_edge_property(Vertex target, const Property& p = Property()) : stored_edge<Vertex>(target), m_property(new Property(p)) { } What am I doing wrong and how can I fix that? Thank you. Regards, Paul

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[filesystem] remove for directories
by Ovanes Markarian 07 Jun '07

07 Jun '07

Hello all! Is there any way to remove a directory using boost::filesystem? remove and remove_all throw an exception. Remove docs reference a POSIX remove(). There is written: [quote] If path does not name a directory, remove(path) shall be equivalent to unlink(path). If path names a directory, remove(path) shall be equivalent to rmdir(path). [/quote] Unfortunately remove does not behave so (on WinXP and Visual C++ 8). One more issue: the link to the POSIX remove() doc points to link() and not remove. With Kind Regards, Ovanes

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Signal not disconnecting?
by Christian Mol 07 Jun '07

07 Jun '07

Hi, I'm using the signal library in my application. However if I call disconnect() on my connection object the connection is not removed. Is this default behaviour? I would like not having this behaviour because the signal is connected to a member function within an object that is actually deleted. Any ideas? Regards, Christian

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BGL compile error
by gast128 07 Jun '07

07 Jun '07

Dear all, We want to (DLL) export a boost graph. Probably on (DLL) exporting, the compiler tries to generate code for every member function. However on VC++7.1 it gives then a problem with operator[]. This can be easily verified with the following case: void Foo() { boost::adjacency_list<> graph; graph[0]; } We use here Boost 1.33.0. Anyone an idea? Wkr, me

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