SFML community forums

General => Feature requests => Topic started by: delahee on August 29, 2019, 11:04:52 pm

Title: glQueries
Post by: delahee on August 29, 2019, 11:04:52 pm

Hey,

Gamedev here. I would like to teach my students to time their draw queries gpu wise, I think the lib could benefit a lot from having proper integration of glQueries with GL_TIME_ELAPSED. I believe for a maintainer it should be a couple hour challenge but as a noob user, I don't really know...

Whatcha think?

Thanks.

Title: Re: glQueries
Post by: binary1248 on August 30, 2019, 12:00:03 am

I don't think this is within the scope of SFML.

• Using this properly requires an understanding of the asynchronous nature of the OpenGL pipeline
• Constantly querying GPU counters will cause a GPU-to-CPU sync anyway leading to a significant decrease in performance, hence previous point
• This requires an extension that is only supported in OpenGL 3+
• If you really needed such functionality, writing a wrapper yourself with the help of sf::Content::isExtensionAvailable and sf::Context::getFunction shouldn't be more than 30 lines of code
• A lof of programming literature out there (especially beginner books like "Programming: Principles and Practice Using C++") provide their own blackbox libraries to help students focus on first learning the concepts at hand rather than their concrete implementations, this would be no different