/// <summary>
/// Calculate the values needed to properly display this <see cref="PieItem"/>.
/// </summary>
/// <param name="pane">
/// A graphic device object to be drawn into. This is normally e.Graphics from the
/// PaintEventArgs argument to the Paint() method.
/// </param>
/// <param name="maxDisplacement">maximum slice displacement</param>
private static void CalculatePieChartParams(GraphPane pane, ref double maxDisplacement)
{
string lblStr = " ";
//loop thru slices and get total value and maxDisplacement
double pieTotalValue = 0;
foreach (PieItem curve in pane.CurveList)
{
if (curve.IsPie)
{
pieTotalValue += curve._pieValue;
if (curve.Displacement > maxDisplacement)
{
maxDisplacement = curve.Displacement;
}
}
}
double nextStartAngle = 0;
//now loop thru and calculate the various angle values
foreach (PieItem curve in pane.CurveList)
{
lblStr = curve._labelStr;
curve.StartAngle = (float)nextStartAngle;
curve.SweepAngle = (float)(360 * curve.Value / pieTotalValue);
curve.MidAngle = curve.StartAngle + curve.SweepAngle / 2;
nextStartAngle = curve._startAngle + curve._sweepAngle;
PieItem.BuildLabelString(curve);
}
}
/// <summary>
/// The Copy Constructor
/// </summary>
/// <param name="rhs">The <see cref="PieItem"/> object from which to copy</param>
public PieItem(PieItem rhs)
: base(rhs)
{
_pieValue = rhs._pieValue;
_fill = rhs._fill.Clone();
this.Border = rhs._border.Clone();
_displacement = rhs._displacement;
_labelDetail = rhs._labelDetail.Clone();
_labelType = rhs._labelType;
_valueDecimalDigits = rhs._valueDecimalDigits;
_percentDecimalDigits = rhs._percentDecimalDigits;
}
/// <summary>
/// Build the string that will be displayed as the slice label as determined by
/// <see cref="LabelType"/>.
/// </summary>
/// <param name="curve">reference to the <see cref="PieItem"/></param>
private static void BuildLabelString(PieItem curve)
{
//set up label string formatting
NumberFormatInfo labelFormat = (NumberFormatInfo)NumberFormatInfo.CurrentInfo.Clone();
labelFormat.NumberDecimalDigits = curve._valueDecimalDigits;
labelFormat.PercentPositivePattern = 1; //no space between number and % sign
labelFormat.PercentDecimalDigits = curve._percentDecimalDigits;
switch (curve._labelType)
{
case PieLabelType.Value:
curve._labelStr = curve._pieValue.ToString("F", labelFormat);
break;
case PieLabelType.Percent:
curve._labelStr = (curve._sweepAngle / 360).ToString("P", labelFormat);
break;
case PieLabelType.Name_Value:
curve._labelStr = curve._label._text + ": " + curve._pieValue.ToString("F", labelFormat);
break;
case PieLabelType.Name_Percent:
curve._labelStr = curve._label._text + ": " + (curve._sweepAngle / 360).ToString("P", labelFormat);
break;
case PieLabelType.Name_Value_Percent:
curve._labelStr = curve._label._text + ": " + curve._pieValue.ToString("F", labelFormat) +
" (" + (curve._sweepAngle / 360).ToString("P", labelFormat) + ")";
break;
case PieLabelType.Name:
curve._labelStr = curve._label._text;
break;
case PieLabelType.None:
default:
break;
}
}
/// <summary>
/// Calculate the <see cref="RectangleF"/> that will be used to define the bounding rectangle of
/// the Pie.
/// </summary>
/// <remarks>This rectangle always lies inside of the <see cref="Chart.Rect"/>, and it is
/// normally a square so that the pie itself is not oval-shaped.</remarks>
/// <param name="g">
/// A graphic device object to be drawn into. This is normally e.Graphics from the
/// PaintEventArgs argument to the Paint() method.
/// </param>
/// <param name="pane">
/// A reference to the <see cref="GraphPane"/> object that is the parent or
/// owner of this object.
/// </param>
/// <param name="scaleFactor">
/// The scaling factor to be used for rendering objects. This is calculated and
/// passed down by the parent <see cref="GraphPane"/> object using the
/// <see cref="PaneBase.CalcScaleFactor"/> method, and is used to proportionally adjust
/// font sizes, etc. according to the actual size of the graph.
/// </param>
/// <param name="chartRect">The <see cref="RectangleF"/> (normally the <see cref="Chart.Rect"/>)
/// that bounds this pie.</param>
/// <returns></returns>
public static RectangleF CalcPieRect(Graphics g, GraphPane pane, float scaleFactor, RectangleF chartRect)
{
//want to draw the largest pie possible within ChartRect
//but want to leave 5% slack around the pie so labels will not overrun clip area
//largest pie is limited by the smaller of ChartRect.height or ChartRect.width...
//this rect (nonExplRect)has to be re-positioned so that it's in the center of ChartRect.
//Where ChartRect is almost a square - low Aspect Ratio -, need to contract pieRect so that there's some
//room for labels, if they're visible.
double maxDisplacement = 0;
RectangleF tempRect; //= new RectangleF(0,0,0,0);
RectangleF nonExplRect = chartRect;
if (pane.CurveList.IsPieOnly)
{
if (nonExplRect.Width < nonExplRect.Height)
{
//create slack rect
nonExplRect.Inflate(-(float)0.05F * nonExplRect.Height, -(float)0.05F * nonExplRect.Width);
//get the difference between dimensions
float delta = (nonExplRect.Height - nonExplRect.Width) / 2;
//make a square so we end up with circular pie
nonExplRect.Height = nonExplRect.Width;
//keep the center point the same
nonExplRect.Y += delta;
}
else
{
nonExplRect.Inflate(-(float)0.05F * nonExplRect.Height, -(float)0.05F * nonExplRect.Width);
float delta = (nonExplRect.Width - nonExplRect.Height) / 2;
nonExplRect.Width = nonExplRect.Height;
nonExplRect.X += delta;
}
//check aspect ratio
double aspectRatio = chartRect.Width / chartRect.Height;
//make an adjustment in rect size,as aspect ratio varies
if (aspectRatio < 1.5)
{
nonExplRect.Inflate(-(float)(.1 * (1.5 / aspectRatio) * nonExplRect.Width),
-(float)(.1 * (1.5 / aspectRatio) * nonExplRect.Width));
}
//modify the rect to determine if any of the labels need to be wrapped....
//first see if there's any exploded slices and if so, what's the max displacement...
//also, might as well get all the display params we can
PieItem.CalculatePieChartParams(pane, ref maxDisplacement);
if (maxDisplacement != 0) //need new rectangle if any slice exploded
{
CalcNewBaseRect(maxDisplacement, ref nonExplRect);
}
foreach (PieItem slice in pane.CurveList)
{
slice._boundingRectangle = nonExplRect;
//if exploded, need to re-calculate rectangle for slice
if (slice.Displacement != 0)
{
tempRect = nonExplRect;
slice.CalcExplodedRect(ref tempRect);
slice._boundingRectangle = tempRect;
}
//now get all the other slice specific drawing details, including need for wrapping label
slice.DesignLabel(g, pane, slice._boundingRectangle, scaleFactor);
}
}
return(nonExplRect);
}
