Ok, the main code is in src/proxy*.js. You can see how basic canvas operations are forwarded there.
The proxying there listens to DOM events and sends them over. For SDL audio, there are a few options and I am not sure which is best. One is to proxy at the C level - replace MIX_* calls in the worker with functions that proxy over. Or, another is to proxy at the HTML Audio object, replace it with a shim that proxies. First step is to look at both of those options, I think. - Alon On Sun, Dec 29, 2013 at 6:53 PM, Richard Janicek <[email protected]> wrote: > Any guidelines you could provide would be much appreciated. I will attempt > to implement. > > > > On Sun, Dec 29, 2013 at 9:30 PM, Alon Zakai <[email protected]> wrote: > >> Yes, audio is possible as well. I don't have plans to work on this myself >> but happy to give guidelines if anyone else wants to. >> >> - Alon >> >> >> >> On Sun, Dec 29, 2013 at 4:54 PM, Richard Janicek <[email protected]>wrote: >> >>> Hello, >>> >>> I am testing --proxy-to-worker with VICE.js. Looks like it's getting >>> +10% performance boost on Chrome. Very nice. >>> >>> Would it be possible to also proxy SDL audio? >>> >>> Best regards, >>> ~Richard Janicek >>> >>> On Saturday, September 14, 2013 12:37:21 AM UTC-4, azakai wrote: >>> >>>> Close to that, yes. SDL_Delay can be implemented as a busy-wait both on >>>> the main thread and in workers, but on the main thread _it blocks >>>> rendering_. On workers, it just blocks event handling; the worker can still >>>> send out paint events. >>>> >>>> This actually happens in Doom, it does screen wipe effects >>>> synchronously. Those are not shown when running on the main thread, because >>>> nothing renders until the event loop is exited. But when running in a >>>> worker, they are shown perfectly. Input events can't be handled during that >>>> time, but in that case it doesn't matter - this might be a problem in other >>>> ones. >>>> >>>> I see it refresh the canvas very quickly, and this is without much >>>> optimization (no typed array transfers, for example). No reason it can't be >>>> 60fps. >>>> >>>> - Alon >>>> >>>> >>>> >>>> >>>> >>>> On Fri, Sep 13, 2013 at 6:34 PM, Richard Janicek <[email protected]>wrote: >>>> >>>>> Oh wow, I think this may work for my app. Does this mean it is >>>>> possible to allow synchronous blocking flow control in the worker thread >>>>> (SDL_Delay) ? How fast can it refresh the canvas, is 60 fps possible? >>>>> >>>>> Thank you very much for this! >>>>> >>>>> § Richard Janicek <http://janicek.co> ¦ mappur <http://mappur.com> ¦ >>>>> player <http://player.janicek.co/#player> ¦ >>>>> clock2d<http://www.clock2d.com/> >>>>> >>>>> >>>>> On Fri, Sep 13, 2013 at 8:47 PM, Alon Zakai <[email protected]>wrote: >>>>> >>>>>> If you use HTML canvas commands like lines, shapes, fills, etc., >>>>>> all those need a 2D canvas context, and do not work in workers (yet). >>>>>> Right >>>>>> now what works is if all you do is render pixels to a buffer and do >>>>>> SDL_UnlockSurface to push them to the screen. >>>>>> >>>>>> But this is temporary, there is spec work going on to get canvas and >>>>>> WebGL to workers, it will happen eventually, see e.g. >>>>>> >>>>>> https://bugzilla.mozilla.org/show_bug.cgi?id=801176 >>>>>> >>>>>> - Alon >>>>>> >>>>>> >>>>>> >>>>>> On Fri, Sep 13, 2013 at 5:44 PM, Richard Janicek <[email protected]>wrote: >>>>>> >>>>>>> What do you mean by "software renderer" ? My app >>>>>>> (VICE.js<http://vice.janicek.co/>) >>>>>>> renders frames to HTML canvas, does this mean I can't take advantage of >>>>>>> this new technique? >>>>>>> >>>>>>> Thank you, >>>>>>> >>>>>>> § Richard Janicek <http://janicek.co> ¦ mappur <http://mappur.com> >>>>>>> ¦ clock2d <http://www.clock2d.com/> >>>>>>> >>>>>>> >>>>>>> On Fri, Sep 13, 2013 at 7:49 PM, Alon Zakai <[email protected]>wrote: >>>>>>> >>>>>>>> 1. Proxing to/from a worker. With >>>>>>>> >>>>>>>> emcc --proxy-to-worker >>>>>>>> >>>>>>>> the compiler will generate html and js files, where the html is a >>>>>>>> small shim that just proxies events to the js, which runs in a worker, >>>>>>>> and >>>>>>>> the js sends back the SDL screen which the html then renders. So >>>>>>>> basically >>>>>>>> this lets you run simple SDL apps in a worker, which is usually good >>>>>>>> for >>>>>>>> performance (doing less on the main thread). >>>>>>>> >>>>>>>> This just supports code that does not use HTML canvas or WebGL, >>>>>>>> because those don't run in workers in browsers (yet). So it will work >>>>>>>> right >>>>>>>> now for a software renderer, for example. I've tested this on Doom. >>>>>>>> >>>>>>>> 2. emscripten_async_load_script (see emscripten.h) >>>>>>>> >>>>>>>> This loads a url into a newly-created HTML script element. This is >>>>>>>> the most efficient way to load a new large amount of code into your app >>>>>>>> (emscripten_run_script converts binary to text, then evals, which is >>>>>>>> worse). It also integrates with the run dependencies system, which >>>>>>>> means >>>>>>>> that you can generate code to preload some files using the file >>>>>>>> packager, >>>>>>>> and emscripten_async_load_script of that will asynchronously load the >>>>>>>> script as well as fetch the file data and prepare it; the callback will >>>>>>>> happen when all the data is ready. This can be used e.g. to load the >>>>>>>> next >>>>>>>> level in your game, at the right time, and in general it can make it >>>>>>>> easier >>>>>>>> to avoid preloading everything at the beginning, which can cause a >>>>>>>> noticeable pause. >>>>>>>> >>>>>>>> - Alon >>>>>>>> >>>>>>>> -- >>>>>>>> You received this message because you are subscribed to the Google >>>>>>>> Groups "emscripten-discuss" group. >>>>>>>> To unsubscribe from this group and stop receiving emails from it, >>>>>>>> send an email to [email protected]. >>>>>>>> For more options, visit https://groups.google.com/groups/opt_out. >>>>>>>> >>>>>>> >>>>>>> -- >>>>>>> You received this message because you are subscribed to the Google >>>>>>> Groups "emscripten-discuss" group. >>>>>>> To unsubscribe from this group and stop receiving emails from it, >>>>>>> send an email to [email protected]. >>>>>>> For more options, visit https://groups.google.com/groups/opt_out. >>>>>>> >>>>>> >>>>>> -- >>>>>> You received this message because you are subscribed to the Google >>>>>> Groups "emscripten-discuss" group. >>>>>> To unsubscribe from this group and stop receiving emails from it, >>>>>> send an email to [email protected]. >>>>>> For more options, visit https://groups.google.com/groups/opt_out. >>>>>> >>>>> >>>>> -- >>>>> You received this message because you are subscribed to the Google >>>>> Groups "emscripten-discuss" group. >>>>> To unsubscribe from this group and stop receiving emails from it, send >>>>> an email to [email protected]. >>>>> For more options, visit https://groups.google.com/groups/opt_out. >>>>> >>>> >>>> -- >>> You received this message because you are subscribed to the Google >>> Groups "emscripten-discuss" group. >>> To unsubscribe from this group and stop receiving emails from it, send >>> an email to [email protected]. >>> For more options, visit https://groups.google.com/groups/opt_out. >>> >> >> -- >> You received this message because you are subscribed to the Google Groups >> "emscripten-discuss" group. >> To unsubscribe from this group and stop receiving emails from it, send an >> email to [email protected]. >> For more options, visit https://groups.google.com/groups/opt_out. >> > > -- > You received this message because you are subscribed to the Google Groups > "emscripten-discuss" group. > To unsubscribe from this group and stop receiving emails from it, send an > email to [email protected]. > For more options, visit https://groups.google.com/groups/opt_out. > -- You received this message because you are subscribed to the Google Groups "emscripten-discuss" group. 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