Almost all graphics systems are single threaded. Some allow additional non rendering event loops but with heavy restrictions that GUI components are only accessed on the main event loop thread.
> On Oct 3, 2023, at 2:00 AM, 'wagner riffel' via golang-nuts > <golang-nuts@googlegroups.com> wrote: > > On Tue Oct 3, 2023 at 05:54 AM UTC, Kurtis Rader wrote: > > Thank you to Ian and TheDiveO. I don't understand why functions like > > gocv.io/x/gocv.NewWindow() have to run on the initial OS thread (at least > > on macOS). > > It's common for C and C++ libraries to use TLS (thread local storage) > to attach data/state to each thread, one example is the global errno > variable used in C to signal errors, each thread read/write its own > variable even though in code they are wirting "the same" variable, > using libc from cgo and reading errno for failures would give wrong > results if the goroutine moved OS threads. It's unrelated which thread > it is and that's why it's not a default, you could start NewWindow at > some point that its goroutine is running in thread4, and if it's not > pinned to run in thread4 you have the same issue with the "initial > thread". > > ps: Specific with graphics, I know OpenGL retains thread-local data, > which might explain why libraries that have this common ancestor needs > to LockOSThread, I'm not sure about Mac and Windows. > > -w > > -- > You received this message because you are subscribed to the Google Groups > "golang-nuts" group. > To unsubscribe from this group and stop receiving emails from it, send an > email to golang-nuts+unsubscr...@googlegroups.com. > To view this discussion on the web visit > https://groups.google.com/d/msgid/golang-nuts/dcbc6ba0-54c8-5942-eb4d-120ba8d65f03%40104d.net. -- You received this message because you are subscribed to the Google Groups "golang-nuts" group. To unsubscribe from this group and stop receiving emails from it, send an email to golang-nuts+unsubscr...@googlegroups.com. To view this discussion on the web visit https://groups.google.com/d/msgid/golang-nuts/DD240547-61CF-40AC-9DDC-C49504203FB4%40ix.netcom.com.
