protected sealed override void RenderPoints([NotNull] IDrawingContext drawingContext, ref Rect clippingRect, bool isCurrentCurve)
{
var controlPointCount = controlPoints.Count;
if (controlPointCount == 0)
{
drawingContext.DrawTexts(new[] { clippingRect.GetCenterLocation() }, Color.LightGray, new[] { $"{Resources.Strings.KeyGestures.GestureAddPoint} to add a keyframe" },
XAxis.FontFamily, XAxis.FontSize * 2, FontWeights.Bold, HorizontalAlignment.Center, VerticalAlignment.Center);
return;
}
#if DEBUG_POINTS_ORDER
var sortedPoints = new List <KeyFrameControlPointViewModel <TValue> >(controlPoints.Count);
var firstPoint = controlPoints[0];
while (firstPoint != null)
{
sortedPoints.Add(firstPoint);
firstPoint = firstPoint.Next as KeyFrameControlPointViewModel <TValue>;
}
#else
// control points can temporarily be unordered during the dragging of one or more points
var sortedPoints = controlPoints.OrderBy(p => p.ActualPoint.X).ToList();
#endif
// sample the curve
var drawPoints = new List <WindowsPoint>();
for (var i = 0; i < controlPointCount - 1; ++i)
{
var samples = SampleControlPoints(sortedPoints[i], sortedPoints[i + 1]);
drawPoints.AddRange(samples.Select(TransformPoint));
}
// last point
drawPoints.Add(sortedPoints[controlPoints.Count - 1].ActualPoint);
// render the curve
RenderLine(drawingContext, ref clippingRect, drawPoints, Color);
if (!isCurrentCurve)
{
return;
}
// Retrieve actual points (and selected actual points)
var actualPoints = new List <WindowsPoint>();
var selectedActualPoints = new List <WindowsPoint>();
foreach (var controlPoint in controlPoints)
{
var actualPoint = controlPoint.ActualPoint;
actualPoints.Add(actualPoint);
if (controlPoint.IsSelected)
{
selectedActualPoints.Add(actualPoint);
}
}
// Render the control points
var radius = ControlPointRadius;
drawingContext.DrawCircles(actualPoints, radius, ControlPointColor, ControlPointColor);
// Render the selection circles over the selected control points
radius *= 2;
drawingContext.DrawCircles(selectedActualPoints, radius, Color.Transparent, Color.WhiteSmoke);
// Render the tangents
// TODO: also render tangents
}