protected override Size MeasureOverride(Size constraint)
{
Children.Clear();
//VisualOperations.GetChildren(this).Clear();
if (double.IsPositiveInfinity(constraint.Width)) { constraint.Width = 500; }
if (double.IsPositiveInfinity(constraint.Height)) { constraint.Height = 500; }
double optimalRows = constraint.Height / (double)VETSHelper.TileSizePixels;
double optimalColumns = constraint.Width / (double)VETSHelper.TileSizePixels;
int neededRows = (int)(Math.Ceiling(optimalRows + 1.0));
int neededColumns = (int)(Math.Ceiling(optimalColumns + 1.0));
WorldCoordinate upperLeft = new WorldCoordinate() { Latitude = CornerLatitude, Longitude = CornerLongitude };
var pixels = Translator.CoordinateToPixels(upperLeft);
int tileX, tileY;
VirtualEarthTileSystem.PixelXYToTileXY((int)pixels.X, (int)pixels.Y, out tileX, out tileY);
TileCoordinate tileStart = new TileCoordinate(tileX, tileY);
Dictionary<TileCoordinate, UIElement> oldDisplays = displays;
displays = new Dictionary<TileCoordinate, UIElement>();
int maxTiles = VETSHelper.MaxTiles(ZoomLevel);
for (int y = tileStart.Y; y < Math.Min(tileStart.Y + neededRows, maxTiles); y++)
{
for (int x = tileStart.X; x < Math.Min(tileStart.X + neededColumns, maxTiles); x++)
{
TileCoordinate cur = new TileCoordinate(x, y);
UIElement child = null;
if (!oldDisplays.ContainsKey(cur))
{
child = CreateChild(cur);
if (child != null)
{
displays[cur] = child;
}
}
else
{
child = displays[cur] = oldDisplays[cur];
}
if (child != null)
{
Children.Add(child);
//VisualOperations.GetChildren(this).Add(child);
child.Measure(constraint);
}
}
}
if (workQueue.Count > 0)
{
workQueue.Dequeue().BeginInvoke(null, null);
}
return constraint;
}
UIElement CreateChild(TileCoordinate tile)
{
string ft;
ft = ".jpg";
string ms = "a";
switch (MapStyle)
{
case MapStyle.Roads:
ms = "r";
ft = ".png";
break;
case MapStyle.Satalite:
ms = "a";
ft = ".jpg";
break;
case MapStyle.Both:
ms = "h";
ft = ".jpg";
break;
}
string qk = VirtualEarthTileSystem.TileXYToQuadKey(tile.X, tile.Y, ZoomLevel);
string fullpath = "http://r0.ortho.tiles.virtualearth.net/tiles/" + ms + qk + ft + "?g=1";
Image img = new Image();
img.Stretch = Stretch.None;
img.Height = img.Width = VETSHelper.TileSizePixels;
img.SnapsToDevicePixels = true;
SetImageSource(img, fullpath);
int absX, absY;
VirtualEarthTileSystem.TileXYToPixelXY(tile.X, tile.Y, out absX, out absY);
Point absolute = new Point(absX, absY);
WorldCoordinate wc = Translator.PixelsToCoordinates(absolute);
SetLatitude(img, wc.Latitude);
SetLongitude(img, wc.Longitude);
return img;
}