private void SetRenderTransform()
{
var tileScale = (double)(1 << TileGrid.ZoomLevel);
var scale = Math.Pow(2d, parentMap.ZoomLevel) / tileScale;
var tileCenter = new Point(tileScale * (0.5 + parentMap.Center.Longitude / 360d),
tileScale * (0.5 - WebMercatorProjection.LatitudeToY(parentMap.Center.Latitude) / 360d));
var tileOrigin = new Point(MapProjection.TileSize * (tileCenter.X - TileGrid.XMin),
MapProjection.TileSize * (tileCenter.Y - TileGrid.YMin));
var viewCenter = new Point(parentMap.RenderSize.Width / 2d, parentMap.RenderSize.Height / 2d);
((MatrixTransform)RenderTransform).Matrix =
MapProjection.CreateTransformMatrix(tileOrigin, scale, parentMap.Heading, viewCenter);
}
private TileGrid GetTileGrid()
{
var tileZoomLevel = Math.Max(0, (int)Math.Round(parentMap.ZoomLevel + ZoomLevelOffset));
var tileScale = (double)(1 << tileZoomLevel);
var scale = tileScale / (Math.Pow(2d, parentMap.ZoomLevel) * MapProjection.TileSize);
var tileCenter = new Point(tileScale * (0.5 + parentMap.Center.Longitude / 360d),
tileScale * (0.5 - WebMercatorProjection.LatitudeToY(parentMap.Center.Latitude) / 360d));
var viewCenter = new Point(parentMap.RenderSize.Width / 2d, parentMap.RenderSize.Height / 2d);
var transform = new MatrixTransform
{
Matrix = MapProjection.CreateTransformMatrix(viewCenter, scale, -parentMap.Heading, tileCenter)
};
var bounds = transform.TransformBounds(new Rect(0d, 0d, parentMap.RenderSize.Width, parentMap.RenderSize.Height));
return(new TileGrid(tileZoomLevel,
(int)Math.Floor(bounds.X), (int)Math.Floor(bounds.Y),
(int)Math.Floor(bounds.X + bounds.Width), (int)Math.Floor(bounds.Y + bounds.Height)));
}
