public void AttachToContainer(CanvasControl result, Panel container, CachedTile tile)
{
_container = container;
if (result != null)
{
_ctrl = result;
}
_container?.Dispatcher?.RunAsync(CoreDispatcherPriority.Normal, () =>
{
if (_ctrl == null)
{
return;
}
if (_ctrl.Tag is TagContainer tag)
{
tag.IsAttached = true;
tag.Tile = tile;
}
else
{
_ctrl.Tag = new TagContainer {
IsAttached = true, Tile = tile
}
};
if (_container?.Children?.Contains(_ctrl) == true)
{
return;
}
_container?.Children?.Add(_ctrl);
RunWaitingCommands();
});
}
/// <summary>
/// Load a tile from the store, and add it to the display container and dictionary
/// If no tile is available in the store at this position, we put an empty proxy in place.
/// </summary>
private void AddToCache(PositionKey key)
{
if (key == null)
{
return;
}
var pos = VisualRectangleNative(key);
var tile = new CachedTile(_displayContainer, key, pos.X, pos.Y); // calls down to "Win2dCanvasManager.Employ"
tile.SetState(TileState.Locked);
lock (_reflowLock)
{
_tileCache.Add(key, tile);
_loadQueue.Enqueue(tile);
}
}
private bool PrepareTileForDraw([NotNull] PositionKey key, out CachedTile tile)
{
lock (_reflowLock)
{
if (!_tileCache.ContainsKey(key))
{
var pos = VisualRectangleNative(key);
var newTile = new CachedTile(_displayContainer, key, pos.X, pos.Y); // calls down to "Win2dCanvasManager.Employ"
newTile.AllocateEmptyImage();
_tileCache.Add(key, newTile);
}
tile = _tileCache[key];
}
if (tile == null)
{
Logging.WriteLogMessage("Tile cache returned null after being populated!");
return(false); // should never happen
}
if (tile.State == TileState.Locked)
{
Logging.WriteLogMessage("Tried to write to a locked tile");
return(false);
}
var dst = tile.GetTileData();
if (dst == null)
{
tile.AllocateEmptyImage();
dst = tile.GetTileData();
}
if (dst == null)
{
throw new Exception("Tile data is missing, even after allocation");
}
return(true);
}
public static CanvasControlAsyncProxy Employ([NotNull] Panel container, [NotNull] CachedTile cachedTile, double x, double y)
{
// Need a new canvas
var proxy = new CanvasControlAsyncProxy(container);
var targetTile = cachedTile;
container.Dispatcher?.RunAsync(CoreDispatcherPriority.High, () =>
{
var ctrl = new CanvasControl
{
Margin = new Thickness(0.0),
Height = 256,
Width = 256,
HorizontalAlignment = HorizontalAlignment.Left,
VerticalAlignment = VerticalAlignment.Top,
UseLayoutRounding = false,
RenderTransform = new TranslateTransform
{
X = x,
Y = y
}
};
proxy.QueueAction(canv =>
{
// We have a single common 'Draw' event hook and use context data to pump in image & state
if (canv == null)
{
return;
}
canv.Draw += _drawHub.Draw;
});
proxy.AttachToContainer(ctrl, container, targetTile);
});
return(proxy);
}
private void WriteTileToBackingStoreSync(PositionKey key, CachedTile tile)
{
if (key == null)
{
return;
}
if (tile == null)
{
return;
}
if (tile.State == TileState.Locked)
{
return;
}
var red = RawDataPool.Capture();
var green = RawDataPool.Capture();
var blue = RawDataPool.Capture();
try
{
var name = key.ToString();
if (tile.ImageIsBlank())
{
_tileStore.Delete(name, "img");
tile.SetState(TileState.Empty);
}
else
{
var packed = tile.GetTileData();
if (packed == null)
{
return;
}
var end = TileImageSize * TileImageSize;
for (int i = 0; i < end; i++)
{
blue[i] = packed[4 * i + 0];
green[i] = packed[4 * i + 1];
red[i] = packed[4 * i + 2];
}
using (var ms = new MemoryStream())
{
WaveletCompress.Compress(red, green, blue, tile.Width, tile.Height).WriteToStream(ms);
ms.Seek(0, SeekOrigin.Begin);
var ok = _tileStore.Store(name, "img", ms);
if (ok.IsFailure)
{
throw new Exception("Storage error: DB might be corrupt.", ok.FailureCause);
}
}
}
}
finally
{
RawDataPool.Release(red);
RawDataPool.Release(green);
RawDataPool.Release(blue);
}
}