Author Topic: Semaphore? (Read 4309 times)

golgoth · « **on:** October 06, 2010, 01:41:51 am »

Greetings,

Is there an equivalent as SDL_CondSignal (Restart a thread wait on a condition variable) within the SFML threads... Semaphore?

thx

Laurent · « **Reply #1 on:** October 06, 2010, 08:04:45 am »

There's no semaphore and no wait condition in SFML (by the way, these two concepts are totally different). If you need this kind of features, you should use a more dedicated threading library.

golgoth · « **Reply #2 on:** October 06, 2010, 09:42:20 am »

Oh i see, that is very unfortunate... thx for pointing that out… just the wait condition would do… any library you would recommend beside SDL?

Laurent · « **Reply #3 on:** October 06, 2010, 10:20:27 am »

boost/std::thread is the most obvious choice. I don't know other threading libraries, but I'm sure there are many good ones available. It depends on what features you want.

golgoth · « **Reply #4 on:** October 07, 2010, 01:18:10 am »

Basically, I`m trying to convert this tutorial:

http://dranger.com/ffmpeg/tutorial03.html

It’s been a nightmare so far… I`m astonish by the lack of support with this, for this tutorials being about 7 years old. I was hoping to make an SFML version. I think video playback would be a great plus for SFML. All it is missing is the equivalent of:

SDL_CondWait();
SDL_CondSignal();

would this be a valuable feature to implement?

With a little guidance setting the audio streaming, it shouldn’t take much to make this work. But I can’t make it happen by myself so far.

Still digging,

golgoth · « **Reply #5 on:** October 07, 2010, 01:54:20 am »

And the rabbit hole goes deeper... std::thread(C++0x) is not implemented in VC++ 2010 and I`m not a fan of boost:: … at all.

I was hoping not to look back at SDL again…

WitchD0ctor · « **Reply #6 on:** October 07, 2010, 01:59:23 am »

You can always use sf video player in the projects forum, easy to use. Only catch is it only supports theora format videos, which is a patent free codec

Laurent · « **Reply #7 on:** October 07, 2010, 08:26:16 am »

Quote

And the rabbit hole goes deeper... std::thread(C++0x) is not implemented in VC++ 2010 and I`m not a fan of boost:: … at all.

I was hoping not to look back at SDL again…

I can't believe that you can't find a threading library that suits your needs, if SFML doesn't provide it.

golgoth · « **Reply #8 on:** October 07, 2010, 05:18:40 pm »

It’s not that I can’t, I’d rather not too... keep library count to a minimum for maintainability sake. when it’s says SFML supports threading I didn’t expect it was partially supported. No worries, I went for a duo SFML / SDL until I find something more elegant.

Nexus · « **Reply #9 on:** October 08, 2010, 12:59:35 am »

Quote from: "golgoth"

And the rabbit hole goes deeper... std::thread(C++0x) is not implemented in VC++ 2010 and I`m not a fan of boost:: … at all.

But you are aware that the std::thread implementation will look pretty similar to boost::thread?

And Boost is used by many C++ programmers. I don't think it's generally a bad idea to create this dependency, as it also offers a lot of other libraries apart from multithreading. By the way, you could abandon SDL instead, so the dependency count is not really an argument.

Maybe you should give Boost a try, it consists of different libraries written by different developers. Or what exactly doesn't please you?