[waffle] [PATCH 0/7] nacl backend implementation

[Tapani]

On 02/05/2015 09:47 AM, Tapani Pälli wrote:
>
> On 02/03/2015 10:07 PM, Chad Versace wrote:
>> It seems that two solutions are available:
>>
>>    S1. Provide waffle_set_swap_buffers_callback().
>>
>>    S2. On Waffle's NaCl backend, implement waffle_swap_buffers() to 
>> block
>>        until the back buffer has been composited onto the web page. 
>> (I believe
>>        this is possible to implement without a worker thread).
>
> I guess it is possible but not without introducing extra 
> latency/slowness for the application thread which I was trying to 
> avoid. Ideally app could continue doing something else while swap goes 
> on.
>

Having experimented this for some time with this I don't think this is 
possible to implement. Problem is that I can't wait in the main thread 
for the callback to be called (blocking somewhere within 
waffle_swap_buffers), the event dispatcher never gets run and there is 
no API to 'flush event queue' or 'run single iteration of event 
dispatcher'. There is way to get pp::MessageLoop of the main thread but 
you can just post more work to it. I vote for the thread, I don't find 
problems with it :)

// Tapani