protected virtual DataRect CoerceVisible(DataRect newVisible)
{
if (Plotter == null)
{
return newVisible;
}
bool isDefaultValue = newVisible == (DataRect)VisibleProperty.DefaultMetadata.DefaultValue;
if (isDefaultValue)
{
newVisible = DataRect.Empty;
}
if (isDefaultValue && IsFittedToView)
{
// determining content bounds
DataRect bounds = DataRect.Empty;
foreach (var item in contentBoundsHosts)
{
IPlotterElement plotterElement = item as IPlotterElement;
if (plotterElement == null)
continue;
if (plotterElement.Plotter == null)
continue;
var plotter = (Plotter2D)plotterElement.Plotter;
var visual = plotter.VisualBindings[plotterElement];
if (visual.Visibility == Visibility.Visible)
{
DataRect contentBounds = Viewport2D.GetContentBounds(item);
if (contentBounds.Width.IsNaN() || contentBounds.Height.IsNaN())
continue;
bounds.UnionFinite(contentBounds);
}
}
if (useApproximateContentBoundsComparison)
{
var intersection = prevContentBounds;
intersection.Intersect(bounds);
double currSquare = bounds.GetSquare();
double prevSquare = prevContentBounds.GetSquare();
double intersectionSquare = intersection.GetSquare();
double squareTopLimit = 1 + maxContentBoundsComparisonMistake;
double squareBottomLimit = 1 - maxContentBoundsComparisonMistake;
if (intersectionSquare != 0)
{
double currRatio = currSquare / intersectionSquare;
double prevRatio = prevSquare / intersectionSquare;
if (squareBottomLimit < currRatio &&
currRatio < squareTopLimit &&
squareBottomLimit < prevRatio &&
prevRatio < squareTopLimit)
{
bounds = prevContentBounds;
}
}
}
prevContentBounds = bounds;
UnitedContentBounds = bounds;
// applying fit-to-view constraints
bounds = fitToViewConstraints.Apply(Visible, bounds, this);
// enlarging
if (!bounds.IsEmpty)
{
bounds = CoordinateUtilities.RectZoom(bounds, bounds.GetCenter(), clipToBoundsEnlargeFactor);
}
else
{
bounds = (DataRect)VisibleProperty.DefaultMetadata.DefaultValue;
}
newVisible.Union(bounds);
}
if (newVisible.IsEmpty)
{
newVisible = (DataRect)VisibleProperty.DefaultMetadata.DefaultValue;
}
else if (newVisible.Width == 0 || newVisible.Height == 0)
{
DataRect defRect = (DataRect)VisibleProperty.DefaultMetadata.DefaultValue;
Size size = newVisible.Size;
Point location = newVisible.Location;
if (newVisible.Width == 0)
{
size.Width = defRect.Width;
location.X -= size.Width / 2;
}
if (newVisible.Height == 0)
{
size.Height = defRect.Height;
location.Y -= size.Height / 2;
}
newVisible = new DataRect(location, size);
}
// apply domain constraint
newVisible = domainConstraint.Apply(Visible, newVisible, this);
// apply other restrictions
if (enforceConstraints)
newVisible = constraints.Apply(Visible, newVisible, this);
// applying transform's data domain constraint
if (!transform.DataTransform.DataDomain.IsEmpty)
{
var newDataRect = newVisible.ViewportToData(transform);
newDataRect = DataRect.Intersect(newDataRect, transform.DataTransform.DataDomain);
newVisible = newDataRect.DataToViewport(transform);
}
if (newVisible.IsEmpty)
newVisible = new Rect(0, 0, 1, 1);
return newVisible;
}
protected void OnRender()
{
if (DesignerProperties.GetIsInDesignMode(this))
return;
if (plotter == null)
return;
panel.Children.Clear();
freeChildren = new List<MapElement>(panel.Children.Count);
for (int i = 0; i < panel.Children.Count; i++)
{
freeChildren.Add((MapElement)panel.Children[i]);
}
rendering = true;
invalidatePending = false;
var transform = plotter.Viewport.Transform;
Rect output = plotter.Viewport.Output;
DataRect visible = plotter.Viewport.Visible;
visibleBounds = visible;
drawnBounds = DataRect.Empty;
var tileInfos = GetVisibleTiles();
var lowerTilesList = GetLoadedLowerTiles(tileInfos);
// displaying lower tiles
foreach (var tile in lowerTilesList)
{
if (server.IsLoaded(tile))
{
var bmp = server[tile];
DataRect visibleRect = tileProvider.GetTileBounds(tile);
DrawImage(bmp, visibleRect, tile);
}
else
{
server.BeginLoadImage(tile);
}
}
int count = 0;
foreach (var tileInfo in tileInfos)
{
drawnBounds.Union(tileInfo.VisibleBounds);
count++;
if (server.IsLoaded(tileInfo.Tile))
{
var bmp = server[tileInfo.Tile];
DrawImage(bmp, tileInfo.VisibleBounds, tileInfo.Tile);
}
else
{
server.BeginLoadImage(tileInfo.Tile);
}
}
showsWholeMap = count == MapTileProvider.GetTotalTilesCount(tileProvider.Level);
foreach (var item in freeChildren)
{
panel.Children.Remove(item);
pool.Put(item);
}
foreach (MapElement item in panel.Children)
{
if (item.Bitmap == null)
{
panel.Children.Remove(item);
pool.Put(item);
}
}
rendering = false;
Debug.WriteLine("Drawn " + Environment.TickCount);
}