private static string GetSourceVersionHash(
IntRect srcTileRect,
ITileStore <ImageTile, TileMetadata> srcTileStore)
{
var s = string.Empty;
foreach (var tilePoint in srcTileRect.EnumPointsZx())
{
var tileMetadata = srcTileStore.GetTileMetadata(tilePoint);
if (tileMetadata != null)
{
s = s + "," + tileMetadata.VersionHash;
}
}
return(GetHash(s));
}
private ZoomOutTileRenderResult RenderZoomOutTiles(
IntRect tileRect,
int tileSize,
IList <RegionPoint> regions)
{
var tileRenderResult = new ZoomOutTileRenderResult();
for (var zoomLevel = -1; zoomLevel >= -6; --zoomLevel)
{
var intRect = tileRect.ZoomBy(zoomLevel);
tileRenderResult.TilesTotal += intRect.Width * intRect.Height;
}
for (var index = -1; index >= -6; --index)
{
Logger.Information("Rendering zoom level {zoom}", index);
var zoomLevel = index + 1;
var tileStore = GetTileStore(tileSize, index);
var srcTileStore = GetTileStore(tileSize, zoomLevel);
foreach (var intPoint1 in tileRect.ZoomBy(index).EnumPointsZx())
{
var tileRegionRect = intPoint1.ToBlockRect(tileSize).ZoomBy(Math.Abs(index)).ToRegionRect();
if (!regions.Any(r => tileRegionRect.Contains(r)))
{
--tileRenderResult.TilesTotal;
}
else
{
var srcTileRect = new IntRect(intPoint1.ZoomBy(1), new IntSize(2, 2));
var sourceVersionHash = GetSourceVersionHash(srcTileRect, srcTileStore);
if (!_force)
{
var tileMetadata = tileStore.GetTileMetadata(intPoint1);
if (tileMetadata != null && sourceVersionHash == tileMetadata.SourceVersionHash &&
tileStore.HasTile(intPoint1))
{
++tileRenderResult.TilesSkipped;
continue;
}
}
Logger.Information("Rendering zoom-out tile z{zoom} t{tile}", index, intPoint1);
var image1 = new Image <Rgba32>(tileSize * 2, tileSize * 2);
image1.Mutate(ctx =>
{
foreach (var tilePoint in srcTileRect.EnumPointsZx())
{
var intPoint = tilePoint - (IntVector)srcTileRect.TopLeft;
var image = srcTileStore.GetTileAsync(tilePoint, CancellationToken.None)
.GetAwaiter().GetResult()?.Image;
if (image == null)
{
ctx.Fill(Rgba32.White,
new Rectangle(intPoint.X * tileSize, intPoint.Z * tileSize,
tileSize, tileSize));
}
else
{
ctx.DrawImage(image,
new Point(intPoint.X * tileSize, intPoint.Z * tileSize), 1f);
}
}
ctx.Resize(new Size(tileSize, tileSize), new BicubicResampler(),
false);
});
tileStore.UpdateOrAddTileAsync(intPoint1, new ImageTile(intPoint1, tileSize, image1))
.GetAwaiter().GetResult();
tileStore.SetTileMetadata(intPoint1, new TileMetadata
{
SourceVersionHash = sourceVersionHash,
VersionHash = GetHash(DateTime.Now.ToString(CultureInfo.InvariantCulture))
});
++tileRenderResult.TilesRendered;
}
}
}
return(tileRenderResult);
}