Sorry for the slow response! At Thu, 11 Jan 2018 12:56:02 -0500, Mark Wunsch wrote: > Yes — that's perfect, thank you! And it also gives me a better sense of how > racket/gui is implemented for macOS. This snippet of code is now included in > my library, and I wonder if there's benefit to having this be available in > racket/gui for cross-platform usage?
The snippet seems fairly specialized to me, and I'm not sure there's a useful cross-platform interpretation. > Now that I understand this a bit, I tried solving the second use-case I wrote > about, using the glimagesink. My understanding of this code is that it > creates > a subview with a CAOpenGLLayer, and then enqueues a `setNeedsDisplay`: > https://github.com/GStreamer/gst-plugins-bad/blob/8d99867c13944be9ba75a89268220 > 4955f16f586/gst-libs/gst/gl/cocoa/gstglwindow_cocoa.m#L332-L354 > > When I run equivalent code outside of racket (e.g. through the gst-launch > tool), I see that I continuously see calls to draw > (https://developer.apple.com/documentation/quartzcore/caopengllayer/1522316-dra > w). Those calls are not being made when run from Racket. > > I realize we're venturing outside of the Realm of Racket (intentional pun) > and closer to Cocoa, but I'd like to have a better sense of how to dequeue > these drawing actions. Based on your previous code, I thought that I could > yield to the main thread by calling `run` or `runUntilDate` on the main > NSRunLoop, but that didn't seem to accomplish this goal. > > Any ideas of how to "yield" to whatever queue or thread GStreamer has running? I'm not sure I'm following, but I think a `setNeedsDisplay` on a view within a `racket/gui` frame will triggers a refresh callback in the normal `racket/gui` event queue. Does the `yield` function from `racket/gui` allow the callback to run in the way you expect? I'd try `yield` applied to a semaphore that's posted by a low-priority callback installed with `queue-callback`, since refresh events will happen with higher priority. There's also `flush-display`. For various reasons, `flush-display` rarely helps, but it may be worth a try. -- You received this message because you are subscribed to the Google Groups "Racket Users" group. To unsubscribe from this group and stop receiving emails from it, send an email to racket-users+unsubscr...@googlegroups.com. For more options, visit https://groups.google.com/d/optout.
