/// <summary>
/// Renders the minor items.
/// </summary>
/// <param name="axis">The axis.</param>
/// <param name="axisPosition">The axis position.</param>
protected virtual void RenderMinorItems(Axis axis, double axisPosition)
{
double eps = axis.ActualMinorStep * 1e-3;
double actualMinimum = axis.ActualMinimum;
double actualMaximum = axis.ActualMaximum;
double plotAreaLeft = this.Plot.PlotArea.Left;
double plotAreaRight = this.Plot.PlotArea.Right;
double plotAreaTop = this.Plot.PlotArea.Top;
double plotAreaBottom = this.Plot.PlotArea.Bottom;
bool isHorizontal = axis.IsHorizontal();
double a0;
double a1;
var minorSegments = new List<ScreenPoint>();
var minorTickSegments = new List<ScreenPoint>();
this.GetTickPositions(axis, axis.TickStyle, axis.MinorTickSize, axis.Position, out a0, out a1);
foreach (double value in this.MinorTickValues)
{
if (value < actualMinimum - eps || value > actualMaximum + eps)
{
continue;
}
if (this.MajorTickValues.Contains(value))
{
continue;
}
if (axis.PositionAtZeroCrossing && Math.Abs(value) < eps)
{
continue;
}
double transformedValue = axis.Transform(value);
if (isHorizontal)
{
SnapTo(plotAreaLeft, ref transformedValue);
SnapTo(plotAreaRight, ref transformedValue);
}
else
{
SnapTo(plotAreaTop, ref transformedValue);
SnapTo(plotAreaBottom, ref transformedValue);
}
// Draw the minor grid line
if (this.MinorPen != null)
{
if (isHorizontal)
{
minorSegments.Add(new ScreenPoint(transformedValue, plotAreaTop));
minorSegments.Add(new ScreenPoint(transformedValue, plotAreaBottom));
}
else
{
if (transformedValue < plotAreaTop || transformedValue > plotAreaBottom)
{
}
minorSegments.Add(new ScreenPoint(plotAreaLeft, transformedValue));
minorSegments.Add(new ScreenPoint(plotAreaRight, transformedValue));
}
}
// Draw the minor tick
if (axis.TickStyle != TickStyle.None && axis.MinorTickSize > 0)
{
if (isHorizontal)
{
minorTickSegments.Add(new ScreenPoint(transformedValue, axisPosition + a0));
minorTickSegments.Add(new ScreenPoint(transformedValue, axisPosition + a1));
}
else
{
minorTickSegments.Add(new ScreenPoint(axisPosition + a0, transformedValue));
minorTickSegments.Add(new ScreenPoint(axisPosition + a1, transformedValue));
}
}
}
// Draw all the line segments);
if (this.MinorPen != null)
{
this.RenderContext.DrawLineSegments(minorSegments, this.MinorPen);
}
if (this.MinorTickPen != null)
{
this.RenderContext.DrawLineSegments(minorTickSegments, this.MinorTickPen);
}
}
/// <summary>
/// Gets the axis title position, rotation and alignment.
/// </summary>
/// <param name="axis">The axis.</param>
/// <param name="titlePosition">The title position.</param>
/// <param name="angle">The angle.</param>
/// <param name="halign">The horizontal alignment.</param>
/// <param name="valign">The vertical alignment.</param>
/// <returns>The <see cref="ScreenPoint" />.</returns>
protected virtual ScreenPoint GetAxisTitlePositionAndAlignment(
Axis axis,
double titlePosition,
ref double angle,
ref HorizontalAlignment halign,
ref VerticalAlignment valign)
{
double middle = axis.IsHorizontal()
? Lerp(axis.ScreenMin.X, axis.ScreenMax.X, axis.TitlePosition)
: Lerp(axis.ScreenMax.Y, axis.ScreenMin.Y, axis.TitlePosition);
if (axis.PositionAtZeroCrossing)
{
middle = Lerp(axis.Transform(axis.ActualMaximum), axis.Transform(axis.ActualMinimum), axis.TitlePosition);
}
switch (axis.Position)
{
case AxisPosition.Left:
return new ScreenPoint(titlePosition, middle);
case AxisPosition.Right:
valign = VerticalAlignment.Bottom;
return new ScreenPoint(titlePosition, middle);
case AxisPosition.Top:
halign = HorizontalAlignment.Center;
valign = VerticalAlignment.Top;
angle = 0;
return new ScreenPoint(middle, titlePosition);
case AxisPosition.Bottom:
halign = HorizontalAlignment.Center;
valign = VerticalAlignment.Bottom;
angle = 0;
return new ScreenPoint(middle, titlePosition);
default:
throw new ArgumentOutOfRangeException("axis");
}
}
/// <summary>
/// Renders the major items.
/// </summary>
/// <param name="axis">The axis.</param>
/// <param name="axisPosition">The axis position.</param>
/// <param name="titlePosition">The title position.</param>
/// <param name="drawAxisLine">Draw the axis line if set to <c>true</c>.</param>
protected virtual void RenderMajorItems(Axis axis, double axisPosition, double titlePosition, bool drawAxisLine)
{
double eps = axis.ActualMinorStep * 1e-3;
double actualMinimum = axis.ActualMinimum;
double actualMaximum = axis.ActualMaximum;
double plotAreaLeft = this.Plot.PlotArea.Left;
double plotAreaRight = this.Plot.PlotArea.Right;
double plotAreaTop = this.Plot.PlotArea.Top;
double plotAreaBottom = this.Plot.PlotArea.Bottom;
bool isHorizontal = axis.IsHorizontal();
double a0;
double a1;
var majorSegments = new List<ScreenPoint>();
var majorTickSegments = new List<ScreenPoint>();
this.GetTickPositions(axis, axis.TickStyle, axis.MajorTickSize, axis.Position, out a0, out a1);
foreach (double value in this.MajorTickValues)
{
if (value < actualMinimum - eps || value > actualMaximum + eps)
{
continue;
}
if (axis.PositionAtZeroCrossing && Math.Abs(value) < eps)
{
continue;
}
double transformedValue = axis.Transform(value);
if (isHorizontal)
{
SnapTo(plotAreaLeft, ref transformedValue);
SnapTo(plotAreaRight, ref transformedValue);
}
else
{
SnapTo(plotAreaTop, ref transformedValue);
SnapTo(plotAreaBottom, ref transformedValue);
}
if (this.MajorPen != null)
{
if (isHorizontal)
{
majorSegments.Add(new ScreenPoint(transformedValue, plotAreaTop));
majorSegments.Add(new ScreenPoint(transformedValue, plotAreaBottom));
}
else
{
majorSegments.Add(new ScreenPoint(plotAreaLeft, transformedValue));
majorSegments.Add(new ScreenPoint(plotAreaRight, transformedValue));
}
}
if (axis.TickStyle != TickStyle.None && axis.MajorTickSize > 0)
{
if (isHorizontal)
{
majorTickSegments.Add(new ScreenPoint(transformedValue, axisPosition + a0));
majorTickSegments.Add(new ScreenPoint(transformedValue, axisPosition + a1));
}
else
{
majorTickSegments.Add(new ScreenPoint(axisPosition + a0, transformedValue));
majorTickSegments.Add(new ScreenPoint(axisPosition + a1, transformedValue));
}
}
}
// Render the axis labels (numbers or category names)
foreach (double value in this.MajorLabelValues)
{
if (value < actualMinimum - eps || value > actualMaximum + eps)
{
continue;
}
if (axis.PositionAtZeroCrossing && Math.Abs(value) < eps)
{
continue;
}
double transformedValue = axis.Transform(value);
if (isHorizontal)
{
SnapTo(plotAreaLeft, ref transformedValue);
SnapTo(plotAreaRight, ref transformedValue);
}
else
{
SnapTo(plotAreaTop, ref transformedValue);
SnapTo(plotAreaBottom, ref transformedValue);
}
var pt = new ScreenPoint();
var ha = HorizontalAlignment.Right;
var va = VerticalAlignment.Middle;
switch (axis.Position)
{
case AxisPosition.Left:
pt = new ScreenPoint(axisPosition + a1 - axis.AxisTickToLabelDistance, transformedValue);
this.GetRotatedAlignments(
axis.Angle,
HorizontalAlignment.Right,
VerticalAlignment.Middle,
out ha,
out va);
break;
case AxisPosition.Right:
pt = new ScreenPoint(axisPosition + a1 + axis.AxisTickToLabelDistance, transformedValue);
this.GetRotatedAlignments(
axis.Angle,
HorizontalAlignment.Left,
VerticalAlignment.Middle,
out ha,
out va);
break;
case AxisPosition.Top:
pt = new ScreenPoint(transformedValue, axisPosition + a1 - axis.AxisTickToLabelDistance);
this.GetRotatedAlignments(
axis.Angle,
HorizontalAlignment.Center,
VerticalAlignment.Bottom,
out ha,
out va);
break;
case AxisPosition.Bottom:
pt = new ScreenPoint(transformedValue, axisPosition + a1 + axis.AxisTickToLabelDistance);
this.GetRotatedAlignments(
axis.Angle,
HorizontalAlignment.Center,
VerticalAlignment.Top,
out ha,
out va);
break;
}
string text = axis.FormatValue(value);
this.RenderContext.DrawMathText(
pt,
text,
axis.ActualTextColor,
axis.ActualFont,
axis.ActualFontSize,
axis.ActualFontWeight,
axis.Angle,
ha,
va);
}
// Draw the zero crossing line
if (axis.PositionAtZeroCrossing && this.ZeroPen != null && this.IsWithin(0, actualMinimum, actualMaximum))
{
double t0 = axis.Transform(0);
if (isHorizontal)
{
this.RenderContext.DrawLine(t0, plotAreaTop, t0, plotAreaBottom, this.ZeroPen);
}
else
{
this.RenderContext.DrawLine(plotAreaLeft, t0, plotAreaRight, t0, this.ZeroPen);
}
}
// Draw extra grid lines
if (axis.ExtraGridlines != null && this.ExtraPen != null)
{
foreach (double value in axis.ExtraGridlines)
{
if (!this.IsWithin(value, actualMinimum, actualMaximum))
{
continue;
}
double transformedValue = axis.Transform(value);
if (isHorizontal)
{
this.RenderContext.DrawLine(
transformedValue,
plotAreaTop,
transformedValue,
plotAreaBottom,
this.ExtraPen);
}
else
{
this.RenderContext.DrawLine(
plotAreaLeft,
transformedValue,
plotAreaRight,
transformedValue,
this.ExtraPen);
}
}
}
if (drawAxisLine)
{
// Draw the axis line (across the tick marks)
if (isHorizontal)
{
this.RenderContext.DrawLine(
axis.Transform(actualMinimum),
axisPosition,
axis.Transform(actualMaximum),
axisPosition,
this.AxislinePen);
}
else
{
this.RenderContext.DrawLine(
axisPosition,
axis.Transform(actualMinimum),
axisPosition,
axis.Transform(actualMaximum),
this.AxislinePen);
}
}
if (this.MajorPen != null)
{
this.RenderContext.DrawLineSegments(majorSegments, this.MajorPen);
}
if (this.MajorTickPen != null)
{
this.RenderContext.DrawLineSegments(majorTickSegments, this.MajorTickPen);
}
}
/// <summary>
/// Transforms the specified point to screen coordinates.
/// </summary>
/// <param name="x">The x value (for the current axis).</param>
/// <param name="y">The y value.</param>
/// <param name="yaxis">The y axis.</param>
/// <returns>The transformed point.</returns>
public virtual ScreenPoint Transform(double x, double y, Axis yaxis)
{
if (yaxis == null)
{
throw new NullReferenceException("Y axis should not be null when transforming.");
}
return new ScreenPoint(this.Transform(x), yaxis.Transform(y));
}
/// <summary>
/// Zooms at the specified position.
/// </summary>
/// <param name="axis">
/// The axis.
/// </param>
/// <param name="factor">
/// The zoom factor.
/// </param>
/// <param name="x">
/// The position to zoom at.
/// </param>
public void ZoomAt(Axis axis, double factor, double x = double.NaN)
{
if (double.IsNaN(x))
{
double sx = (axis.Transform(axis.ActualMaximum) + axis.Transform(axis.ActualMinimum)) * 0.5;
x = axis.InverseTransform(sx);
}
axis.ZoomAt(factor, x);
}
/// <summary>
/// Returns the angle (in radian) of the axis line in screen coordinate
/// </summary>
/// <param name="axis">The axis.</param>
/// <param name="angleAxis">The angle axis.</param>
/// <returns>The angle (in radians).</returns>
private static double GetActualAngle(Axis axis, Axis angleAxis)
{
var a = axis.Transform(0, angleAxis.Angle, angleAxis);
var b = axis.Transform(1, angleAxis.Angle, angleAxis);
return Math.Atan2(b.y - a.y, b.x - a.x);
}
/// <summary>
/// Renders major tick text
/// </summary>
/// <param name="axis">The axis.</param>
/// <param name="x">The x-value.</param>
/// <param name="angleAxis">The angle axis.</param>
private void RenderTickText(Axis axis, double x, Axis angleAxis)
{
var actualAngle = GetActualAngle(axis, angleAxis);
var dx = axis.AxisTickToLabelDistance * Math.Sin(actualAngle);
var dy = -axis.AxisTickToLabelDistance * Math.Cos(actualAngle);
HorizontalAlignment ha;
VerticalAlignment va;
GetTickTextAligment(actualAngle, out ha, out va);
var pt = axis.Transform(x, angleAxis.Angle, angleAxis);
pt = new ScreenPoint(pt.X + dx, pt.Y + dy);
string text = axis.FormatValue(x);
this.RenderContext.DrawMathText(
pt,
text,
axis.ActualTextColor,
axis.ActualFont,
axis.ActualFontSize,
axis.ActualFontWeight,
axis.Angle,
ha,
va);
}
/// <summary>
/// Renders a tick by drawing an lot of segments
/// </summary>
/// <param name="axis">The axis.</param>
/// <param name="angleAxis">The angle axis.</param>
/// <param name="x">The x-value.</param>
/// <param name="pen">The pen.</param>
private void RenderTickArc(Axis axis, AngleAxis angleAxis, double x, OxyPen pen)
{
// caution: make sure angleAxis.UpdateActualMaxMin(); has been called
var minAngle = angleAxis.ActualMinimum;
var maxAngle = angleAxis.ActualMaximum;
// number of segment to draw a full circle
// - decrease if you want get more speed
// - increase if you want more detail
// (making a public property of it would be a great idea)
const double MaxSegments = 90.0;
// compute the actual number of segments
var segmentCount = (int)(MaxSegments * Math.Abs(angleAxis.EndAngle - angleAxis.StartAngle) / 360.0);
var angleStep = (maxAngle - minAngle) / (segmentCount - 1);
var points = new List<ScreenPoint>();
for (var i = 0; i < segmentCount; i++)
{
var angle = minAngle + (i * angleStep);
points.Add(axis.Transform(x, angle, angleAxis));
}
this.RenderContext.DrawLine(points, pen.Color, pen.Thickness, pen.ActualDashArray);
}
/// <summary>
/// Renders a tick by drawing an ellipse
/// </summary>
/// <param name="axis">The axis.</param>
/// <param name="angleAxis">The angle axis.</param>
/// <param name="x">The x-value.</param>
/// <param name="pen">The pen.</param>
private void RenderTickCircle(Axis axis, Axis angleAxis, double x, OxyPen pen)
{
var zero = angleAxis.Offset;
var center = axis.Transform(axis.ActualMinimum, zero, angleAxis);
var right = axis.Transform(x, zero, angleAxis).X;
var radius = right - center.X;
var width = radius * 2;
var left = right - width;
var top = center.Y - radius;
var height = width;
this.RenderContext.DrawEllipse(new OxyRect(left, top, width, height), OxyColors.Undefined, pen.Color, pen.Thickness);
}
/// <summary>
/// Transforms the specified point to screen coordinates.
/// </summary>
/// <param name="p">
/// The point.
/// </param>
/// <param name="xaxis">
/// The x axis.
/// </param>
/// <param name="yaxis">
/// The y axis.
/// </param>
/// <returns>
/// The transformed point.
/// </returns>
public static ScreenPoint Transform(IDataPoint p, Axis xaxis, Axis yaxis)
{
return xaxis.Transform(p.X, p.Y, yaxis);
}
