// 將不同interval的方程式加到hp term中
private void DetermineEquationToHpTerm(Equation eq, Intersaction intersaction)
{
if (eq.X != 0)
{
if (eq.X > 0)
{
_hpTerm.AddEquation(new Equation(eq.Constant, eq.X, eq.X2, intersaction.X, eq.MaxInterval));
}
else
{
_hpTerm.AddEquation(new Equation(eq.Constant, eq.X, eq.X2, eq.MinInterval, intersaction.X));
}
}
else
{
Equation parallel = (intersaction.Equation1.X == 0) ? intersaction.Equation1 : intersaction.Equation2;
Equation slash = (intersaction.Equation1.X != 0) ? intersaction.Equation1 : intersaction.Equation2;
if (slash.X > 0)
{
parallel.MaxInterval = intersaction.X;
}
else
{
parallel.MinInterval = intersaction.X;
}
_hpTerm.AddEquation(parallel);
}
}
// 若交點y不是最大或跟其他交點相同的則清除它
private bool CleanIntersaction(Intersaction intersaction, Term term)
{
if (!term.IsInInterval(intersaction.X))
{
return(false);
}
foreach (Equation eq in term.Equations)
{
if (eq.IsInInterval(intersaction.X) && eq.GetY(intersaction.X) > intersaction.Y)
{
_intersactions.Remove(intersaction);
return(true);
}
}
return(false);
}
// 判斷是否重疊並加入交點
private void AddIntersaction(Equation lhs, Equation rhs)
{
if (lhs.IsEquationsIntervalOverlap(rhs) && !lhs.IsEqual(rhs))
{
// 1 y = ax + b
// 2 y = cx + d
// 1-2 -(b - d) / (a - c)
double x = -(lhs.Constant - rhs.Constant) / (lhs.X - rhs.X);
double y = lhs.X * x + lhs.Constant;
Intersaction newInter = new Intersaction(x, y, lhs, rhs);
if (lhs.MinInterval <= x && x <= lhs.MaxInterval &&
rhs.MinInterval <= x && x <= rhs.MaxInterval &&
!_intersactions.Any(eq => eq.IsEqual(newInter)))
{
_intersactions.Add(newInter);
}
}
}
// 判斷是否一樣
public bool IsEqual(Intersaction intersaction)
{
return(_x == intersaction.X &&
_y == intersaction.Y);
}