/// <summary>
/// Calculates slicing plane top offset
/// </summary>
/// <param name="Atar">Target area</param>
/// <returns>Offset of the slicing plane from the top</returns>
public double GetSlicePlaneTopOffset(double Atar)
{
double SlicePlaneCoordinate = 0.0;
double Sum_hi = 0; //summation of height of previous rectangles
double Sum_Ai = 0; //summation of areas of previous rectangles
var sortedRectanglesX = RectanglesXAxis.OrderByDescending(r => r.InsertionPoint.Y).ToList();
foreach (var r in sortedRectanglesX)
{
double bn = r.b;
double hn = r.h;
double hn_actual = r.h_a; //actual height used for fillet areas
double yn = 0;
double An = bn * hn;
//distance from top of the rectangle to the slicing plane
//this number is meaningful only for one rectangle
double h_n_tilda = (Atar - Sum_Ai) / bn;
double Y_n_tilda = 0;
//check if this rectangle is the one where
//slice plane is located
if (h_n_tilda > 0 && h_n_tilda <= hn)
{
//this condition is met only for one rectangle
Y_n_tilda = Sum_hi + h_n_tilda;
SlicePlaneCoordinate = Y_n_tilda;//slicing plane coordinate is measured from top
}
Sum_Ai += An;
Sum_hi += hn_actual;
}
return(SlicePlaneCoordinate);
}
private void CalculatePlasticProperties()
{
//sort rectangles collection to make sure that they go from top to bottom
var sortedRectanglesX = RectanglesXAxis.OrderByDescending(r => r.InsertionPoint.Y).ToList();
CalculatePlasticSectionModulus(AnalysisAxis.X, sortedRectanglesX);
//sort rectangles collection to make sure that they go from left to right
if (RectanglesYAxis != null)
{
var sortedRectanglesY = RectanglesYAxis.OrderBy(r => r.InsertionPoint.X).ToList();
CalculatePlasticSectionModulus(AnalysisAxis.Y, sortedRectanglesY);
}
}
/// <summary>
/// Calculates a section based on slicing criteria
/// </summary>
/// <param name="YCoordinate">Plane Y coordinate in local coordinate system</param>
/// <param name="sliceType">Indicates whether top or bottom slice is returned</param>
/// <returns></returns>
private IMoveableSection getSliceAtCoordinate(double YCoordinate, SliceType sliceType)
{
ArbitraryCompoundShape newShape = new ArbitraryCompoundShape(null, null);
if (sliceType == SliceType.Top)
{
var sortedRectanglesX = RectanglesXAxis.OrderByDescending(r => r.InsertionPoint.Y).ToList();
foreach (var r in sortedRectanglesX)
{
if (r.Ymax > YCoordinate && r.Ymin >= YCoordinate)
{
newShape.rectanglesXAxis.Add(r);
}
else if (r.Ymax >= YCoordinate && r.Ymin <= YCoordinate)
{
double thisRectHeight = r.Ymax - YCoordinate;
newShape.rectanglesXAxis.Add(new CompoundShapePart(r.b, thisRectHeight, new Point2D(0, r.Ymax - thisRectHeight / 2.0)));
}
else
{
//do nothing since this rectangle does not belong here
}
}
}
else
{
var sortedRectanglesX = RectanglesXAxis.OrderBy(r => r.InsertionPoint.Y).ToList();
foreach (var r in sortedRectanglesX)
{
if (r.Ymax <= YCoordinate && r.Ymin < YCoordinate)
{
newShape.rectanglesXAxis.Add(r);
}
else if (r.Ymax > YCoordinate && r.Ymin <= YCoordinate)
{
double thisRectHeight = YCoordinate - r.Ymin;
newShape.rectanglesXAxis.Add(new CompoundShapePart(r.b, thisRectHeight, new Point2D(0, r.Ymin + thisRectHeight / 2.0)));
}
else
{
//do nothing since this rectangle does not belong here
}
}
}
return(newShape);
}
