Method add_tile_to_cache

src/libtexture/imagecache.cpp:1919–1957

void
ImageCacheImpl::add_tile_to_cache (ImageCacheTileRef &tile,
                                   ImageCachePerThreadInfo *thread_info)
{
    bool ourtile = true;
    {
        // Protect us from using too much memory if another thread added the
        // same tile just before us
        TileCache::iterator found = m_tilecache.find (tile->id());
        if (found != m_tilecache.end ()) {
            // Already added!  Use the other one, discard ours.
            tile = (*found).second;
            found.unlock ();
            ourtile = false;  // Don't need to add it
        } else {
            // Still not in cache, add ours to the cache.
            // N.B. at this time, we do not hold any locks.
            check_max_mem (thread_info);
            m_tilecache.insert (tile->id(), tile);
        }
    }

    // At this point, we no longer have the write lock, and we are no
    // longer modifying the cache itself.  However, if we added a new
    // tile to the cache, we may still need to read the pixels; and if
    // we found the tile in cache, we may need to wait for somebody else
    // to read the pixels.
    if (ourtile) {
        if (! tile->pixels_ready ()) {
            Timer timer;
            tile->read (thread_info);
            double readtime = timer();
            thread_info->m_stats.fileio_time += readtime;
            tile->id().file().iotime() += readtime;
        }
    } else {
        tile->wait_pixels_ready ();
    }
}