public override void Render(IRenderContext rc, PlotModel model)
{
if (Slices.Count == 0)
{
return;
}
var total = Slices.Sum(slice => slice.Value);
if (Math.Abs(total) < double.Epsilon)
{
return;
}
var radius = Math.Min(model.PlotArea.Width, model.PlotArea.Height) / 2;
var outerRadius = radius * (Diameter - ExplodedDistance);
var innerRadius = radius * InnerDiameter;
var angle = StartAngle;
var midPoint = new ScreenPoint((model.PlotArea.Left + model.PlotArea.Right) * 0.5, (model.PlotArea.Top + model.PlotArea.Bottom) * 0.5);
foreach (var slice in Slices)
{
var outerPoints = new List <ScreenPoint>();
var innerPoints = new List <ScreenPoint>();
var sliceAngle = slice.Value / total * AngleSpan;
var endAngle = angle + sliceAngle;
var explodedRadius = slice.IsExploded ? ExplodedDistance * radius : 0.0;
var midAngle = angle + sliceAngle / 2;
var midAngleRadians = midAngle * Math.PI / 180;
var mp = new ScreenPoint(
midPoint.X + explodedRadius * Math.Cos(midAngleRadians),
midPoint.Y + explodedRadius * Math.Sin(midAngleRadians));
// Create the pie sector points for both outside and inside arcs
while (true)
{
var stop = false;
if (angle >= endAngle)
{
angle = endAngle;
stop = true;
}
var a = angle * Math.PI / 180;
var op = new ScreenPoint(mp.X + outerRadius * Math.Cos(a), mp.Y + outerRadius * Math.Sin(a));
outerPoints.Add(op);
var ip = new ScreenPoint(mp.X + innerRadius * Math.Cos(a), mp.Y + innerRadius * Math.Sin(a));
if (innerRadius + explodedRadius > 0)
{
innerPoints.Add(ip);
}
if (stop)
{
break;
}
angle += AngleIncrement;
}
innerPoints.Reverse();
if (innerPoints.Count == 0)
{
innerPoints.Add(mp);
}
innerPoints.Add(outerPoints[0]);
var points = outerPoints;
points.AddRange(innerPoints);
rc.DrawPolygon(points, slice.ActualFillColor, Stroke, StrokeThickness, null, LineJoin.Bevel);
}
angle = StartAngle;
foreach (var slice in Slices)
{
var sliceAngle = slice.Value / total * AngleSpan;
var explodedRadius = slice.IsExploded ? ExplodedDistance * radius : 0.0;
var midAngle = angle + sliceAngle / 2;
var midAngleRadians = midAngle * Math.PI / 180;
var mp = new ScreenPoint(
midPoint.X + explodedRadius * Math.Cos(midAngleRadians),
midPoint.Y + explodedRadius * Math.Sin(midAngleRadians));
angle = angle + sliceAngle;
// Render label outside the slice
if (OutsideLabelFormat != null)
{
var label = string.Format(
OutsideLabelFormat, slice.Value, slice.Label, slice.Value / total * 100);
var sign = Math.Sign(Math.Cos(midAngleRadians));
// tick points
var tp0 = new ScreenPoint(
mp.X + (outerRadius + TickDistance) * Math.Cos(midAngleRadians),
mp.Y + (outerRadius + TickDistance) * Math.Sin(midAngleRadians));
var tp1 = new ScreenPoint(
tp0.X + TickRadialLength * Math.Cos(midAngleRadians),
tp0.Y + TickRadialLength * Math.Sin(midAngleRadians));
var tp2 = new ScreenPoint(tp1.X + TickHorizontalLength * sign, tp1.Y);
rc.DrawLine(new[] { tp0, tp1, tp2 }, Stroke, 1d, null, LineJoin.Bevel);
// label
var labelPosition = new ScreenPoint(tp2.X + TickLabelDistance * sign, tp2.Y);
DrawTextWithShadow(rc, labelPosition, label, ActualTextColor, ActualFont, ActualFontSize, ActualFontWeight,
0, sign > 0 ? HorizontalAlignment.Left : HorizontalAlignment.Right, VerticalAlignment.Middle);
}
// Render label inside the slice
if (InsideLabelFormat != null)
{
var label = string.Format(
InsideLabelFormat, slice.Value, slice.Label, slice.Value / total * 100);
var r = innerRadius * (1 - InsideLabelPosition) + outerRadius * InsideLabelPosition;
var labelPosition = new ScreenPoint(
mp.X + r * Math.Cos(midAngleRadians), mp.Y + r * Math.Sin(midAngleRadians));
double textAngle = 0;
if (AreInsideLabelsAngled)
{
textAngle = midAngle;
if (Math.Cos(midAngleRadians) < 0)
{
textAngle += 180;
}
}
DrawTextWithShadow(rc, labelPosition, label, ActualTextColor, ActualFont, ActualFontSize, ActualFontWeight,
textAngle, HorizontalAlignment.Center, VerticalAlignment.Middle);
}
}
void DrawTextWithShadow(IRenderContext context, ScreenPoint p, string text, OxyColor fill, string fontFamily = null, double fontSize = 10.0, double fontWeight = 400.0,
double rotation = 0.0, HorizontalAlignment horizontalAlignment = HorizontalAlignment.Left,
VerticalAlignment verticalAlignment = VerticalAlignment.Top, OxySize?maxSize = null)
{
for (var i = -1; i <= 1; ++i)
{
for (var j = -1; j <= 1; ++j)
{
if (Math.Abs(i) + Math.Abs(j) != 1)
{
continue;
}
context.DrawText(p + new ScreenVector(i, j), text, OxyColors.Black, fontFamily, fontSize, fontWeight,
rotation, horizontalAlignment, verticalAlignment, maxSize);
}
}
context.DrawText(p, text, fill, fontFamily, fontSize, fontWeight, rotation, horizontalAlignment, verticalAlignment, maxSize);
}
}
