threading.cpp


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static void
PushRect(rectangle RenderRegion)
{
    uint32 Q = SDL_AtomicGet(&QueuedEntries);
    render_entry *Entry = Entries + Q;
    Entry->RenderRegion = RenderRegion;
    SDL_AtomicAdd(&QueuedEntries, 1);
    SDL_SemPost(Semaphore);
}

static void
RenderLayers(render_queue *RenderInfo, rectangle RenderRegion);

static bool32
CheckQueue(render_queue RenderInfo, uint16 Index)
{
    bool32 Result = 0;
    uint32 Q = SDL_AtomicGet(&QueuedEntries);
    uint32 C = SDL_AtomicGet(&CurrentEntry);
    if (Q > C)
        {
            if (SDL_AtomicCAS(&CurrentEntry, C, C + 1)) {
                render_entry *Entry = Entries + C;
                Assert(Entry->RenderRegion.Max.x != 0);
                RenderLayers(&RenderInfo, Entry->RenderRegion);
                // printf("(FINISHED) Thread %i, region X%i Y%i\n", Index, Entry->RenderRegion.Min.x/240, Entry->RenderRegion.Min.y/135);
                SDL_AtomicAdd(&CompletedEntries, 1);
                Result = 1;
            }
        }
    return Result;
}

static int
TestThread(void *ptr)
{
    thread_info *ThreadInfo = (thread_info *)ptr;
    uint16 Index = ThreadInfo->Index;
    for(;;)
    {
        if (!CheckQueue(*ThreadInfo->RenderInfo, Index))
        {
            SDL_SemWait(Semaphore);
        }
    }
}