Example usage of the core.sync classes

[Benjamin Thaut via Digitalmars-d-learn]

Am 02.01.2015 um 19:45 schrieb Vlad Levenfeld:
>
> My personal favorite method is to use the primitives in core.atomic with
> a double or triple buffer. To double buffer, keep two buffers in an
> array (data[][] or something) and an integer index that points to the
> active buffer, then use atomicStore to update active buffer index when
> you want to swap.
> Triple buffering can improve runtime performance at the cost of more
> memory, and in this case you will need two indices and two swap methods,
> one for the producer and another for the consumer. I use cas with a
> timed sleep to update the indices in this case.
>
> Take it with a grain of salt, I'm far from a pro, but this has worked
> well for me in the past. I can post some example code if you need it.

I have to agree with Vlad here. The usual way is to do double buffering. 
So you have two buffers which hold all the data that the physics 
simulation passes to the game logic. While the physics simulation is 
computing the next frame, the game logic can use the results from the 
last frame. The only point where sinchronisation is neccessary is when 
swapping the buffers. You have to ensure that both the game logic and 
the physics thread are done with their current buffer and then sawp 
them. The only downside of this approach is, that you will get a small 
delay (usually the time taken for 1 frame) into the data you pass this 
way. Sometimes this approach is called the "exractor pattern". I use it 
to pass data from the game simulation to the renderer, so the renderer 
can render in paralell with the game simulation computing the next 
frame. You can find a example of my double buffered solution here:
https://github.com/Ingrater/Spacecraft/blob/master/game/sources/renderer/extractor.d

I had tripple buffering up and running at some point, but I went back to 
double buffering, because tripple buffering can cause micro lags and you 
don't want that.

Kind Regards
Benjamin Thaut