multithreading_support(3)

💖 multithreading_support(3) 💖

okay bestie, welcome to the manual page for multithreading_support — yes that's the name, yes it's a lot of syllables, we move.

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🌸 NAME 🌸

multithreading_support — Multithreading Support in Coin 🧵✨

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🦋 DESCRIPTION 🦋

so Coin has this whole thing where it supports using multiple threads in application programs and inside the Coin library itself, and it's giving two main features, no cap:

• Coin hands you platform-independent thread-handling abstraction classes. Like, these are classes the application programmer can freely use in her application code to start new threads, control their execution, work with mutexes, and do all the other tasks related to handling multiple threads. 🫶

The classes in question are SbThread, SbMutex, SbStorage, SbBarrier, SbCondVar, SbFifo, SbThreadAutoLock, SbRWMutex, and SbTypedStorage. Go read their respective documentation for the detailed tea, bestie. 👑

These classes fully hide the system-specific implementation, which is either done on top of native Win32 (if you're on Microsoft Windows), or over POSIX threads (on UNIX and UNIX-like systems). So you don't gotta worry about it. periodt.

• The other aspect of this multi-threading support is that Coin can be specially configured so that rendering traversals of the scene graph are done in a thread-safe manner. This means, like, it's possible to have Coin render the scene in parallel on multiple CPUs for multiple rendering pipes, to better take advantage of such high-end systems (like CAVE environments, for instance). iconic honestly. 🔥

Thread-safe render traversals are off by default, because there's a small overhead involved which would make rendering (very) slightly slower on single-threaded invocations. a tiny little tax. 🙈

To get a Coin library built with thread-safe rendering, you must actively re-configure Coin and build a special, local version. For configure-based builds (UNIX and UNIX-like systems, or with Cygwin on Microsoft Windows) this is done with the option --enable-threadsafe to Autoconf configure. For how to change the configuration and re-build with Visual Studio, get in touch with us at coin-support@coin3d.org. 💌

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🚧 Restrictions & Other Issues You Gotta Know About 🚧

There are some restrictions and other issues which it is important to be aware of:

• We do not yet provide any support for binding the multi-threaded rendering support into the SoQt / SoWin / etc GUI bindings, and neither do we provide bindings against any specific library that handles multi-pipe rendering. This means the application programmer will have to possess some expertise, and put in some effort, to be able to utilize multi-pipe rendering with Coin. it's giving homework. 😭
• Rendering traversals is currently the only operation which we publicly support to be thread-safe. There are other aspects of Coin that we know are thread-safe, like most other action traversals beside just rendering, but we make no guarantees in this regard. ngl, don't @ us. 💀
• Be careful about using a separate thread for changing Coin structures versus what is used for the application's GUI event thread. ⚠️

We are aware of at least issues with Qt (and thereby SoQt), where you should not modify the scene graph in any way in a thread separate from the main Qt thread. This because it will trigger operations where Qt is not thread-safe. do not do it bestie, I'm begging. 🥺

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⭐ SINCE ⭐

Coin 2.0

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and that's the whole page, mwah 💅 this was written for Coin Version 3.1.3 — Library Functions Manual energy, and yes the original footer was literally just Coin Version 3.1.3 + multithreading_support(3) with no date, so that's what you're getting. slay, stay thread-safe out there 🧚💖