public override void Draw(DrawingContext drawingContext, ulong firstVisibleTick, ulong lastVisibleTick)
{
Rect r = new Rect(0, 0, this.ActualWidth, this.ActualHeight);
drawingContext.DrawRectangle(this.IsKeyboardFocused ? this.FocusedBackground : this.Background, null, r);
if (this.DataSource == null)
{
return;
}
UpdateBitmap();
drawingContext.PushClip(new RectangleGeometry(r));
List<LabeledRange> labeledRanges = new List<LabeledRange>();
FormattedText ftLabel = null;
const double textMargin = 3;
if (this.LabelFontSize > 0)
{
// Calculate label rect requirements
foreach (var selectedNode in this.selectedNodes)
{
// We're +1 because there is some kind of sub-pixel misalignment between the event lane itself and the bitmap.
var middle = TimeAxis.TimeToScreen(selectedNode.StartTime + (selectedNode.Duration / 2)) + 1;
var x1 = TimeAxis.TimeToScreen(selectedNode.StartTime) + 1;
var x2 = TimeAxis.TimeToScreen(selectedNode.StartTime + selectedNode.Duration) + 1;
if (x1 <= this.PixelWidth && x2 > 0)
{
if (ftLabel == null)
{
// NOTE: It is assumed that all selected nodes have the same name...
ftLabel = new FormattedText(selectedNode.Name, CultureInfo.CurrentCulture, FlowDirection.LeftToRight,
this.labelTypeface, this.LabelFontSize, this.IsKeyboardFocused ? this.FocusedSelectionForeground : this.SelectionForeground);
}
// Try to center the label under the node. But adjust its position if it
// is clipped by the left or right edge of the timeline.
var left = middle - ftLabel.Width / 2;
if (left < textMargin)
{
left = textMargin;
}
else if (left + ftLabel.Width > this.ActualWidth - textMargin)
{
left = this.ActualWidth - textMargin - ftLabel.Width;
}
// Create a labeled range for this label
var range = new LabeledRange();
range.Start = x1;
range.End = x2;
range.Rect = new Rect(left, this.palette.BitmapPixelHeight, ftLabel.Width, this.SelectionFanHeight + this.labelTextHeight + (this.LabelMargin * 2));
range.Rect.Inflate(textMargin, 0);
range.ContainsPrimaryNode = (selectedNode == this.primarySelectedNode);
labeledRanges.Add(range);
}
}
}
if (ftLabel != null)
{
List<LabeledRange> mergedRanges = new List<LabeledRange>(labeledRanges.Count);
// Merge the overlapping label rects together
while (labeledRanges.Count > 0)
{
LabeledRange range = labeledRanges[0];
labeledRanges.RemoveAt(0);
for (int i = 0; i < labeledRanges.Count; )
{
if (range.Rect.IntersectsWith(labeledRanges[i].Rect))
{
range.Union(labeledRanges[i]);
labeledRanges.RemoveAt(i);
}
else
{
i++;
}
}
double centerX = range.Rect.Left + (range.Rect.Width / 2) - (ftLabel.Width / 2);
range.Rect = new Rect(centerX, range.Rect.Top, ftLabel.Width, range.Rect.Height);
range.Rect.Inflate(textMargin, 0);
mergedRanges.Add(range);
}
double textRectTop = this.DesiredSize.Height - (ftLabel.Height + this.LabelMargin + this.BottomMargin);
double textRectBottom = this.DesiredSize.Height - this.BottomMargin;
// Draw the remaining labeled ranges
foreach (var range in mergedRanges)
{
double centerX = range.Rect.Left + (range.Rect.Width / 2) - (ftLabel.Width / 2);
var geometry = new StreamGeometry() { FillRule = FillRule.EvenOdd };
using (StreamGeometryContext ctx = geometry.Open())
{
ctx.BeginFigure(new Point(range.End, range.Rect.Top), isFilled: true, isClosed: true);
ctx.LineTo(new Point(range.Rect.Right, textRectTop), true, true);
ctx.LineTo(new Point(range.Rect.Right, textRectBottom), true, true);
ctx.LineTo(new Point(range.Rect.Left, textRectBottom), true, true);
ctx.LineTo(new Point(range.Rect.Left, textRectTop), true, true);
if (range.SubRanges == null)
{
ctx.LineTo(new Point(range.Start, range.Rect.Top), true, true);
}
else
{
double inc = range.Rect.Width / range.SubRanges.Count;
double nextValley = range.Rect.Left + inc;
for (int i = 0; i < range.SubRanges.Count; i++)
{
var subrange = range.SubRanges[i];
ctx.LineTo(new Point(subrange.Item1, range.Rect.Top), true, true);
if (i < range.SubRanges.Count - 1)
{
ctx.LineTo(new Point(subrange.Item2, range.Rect.Top), false, true);
ctx.LineTo(new Point(nextValley, textRectTop), true, true);
nextValley += inc;
}
}
}
ctx.LineTo(new Point(range.End, range.Rect.Top), false, true);
}
var brush = this.Background;
var foreground = this.Foreground;
if (this.IsKeyboardFocused)
{
if (range.ContainsPrimaryNode)
{
brush = this.FocusedSelectionBackground;
foreground = this.FocusedSelectionForeground;
}
else
{
brush = this.FocusedBackground;
foreground = this.FocusedForeground;
}
}
drawingContext.DrawGeometry(brush, this.standardPen, geometry);
ftLabel.SetForegroundBrush(foreground);
drawingContext.DrawText(ftLabel, new Point(centerX, textRectTop));
}
}
drawingContext.Pop();
}
public void Union(LabeledRange range)
{
if (this.SubRanges == null)
{
this.SubRanges = new List<Tuple<double, double>>();
this.SubRanges.Add(new Tuple<double, double>(this.Start, this.End));
}
this.Start = Math.Min(this.Start, range.Start);
this.End = Math.Max(this.End, range.End);
this.Rect.Union(range.Rect);
if (range.SubRanges == null)
{
this.SubRanges.Add(new Tuple<double, double>(range.Start, range.End));
}
else
{
this.SubRanges.AddRange(range.SubRanges);
}
this.ContainsPrimaryNode |= range.ContainsPrimaryNode;
}