//TODO: I can use CheckNotTriangleException but i don't know is it neccessary
private void CheckNotTriangleException(FixedVertex2D a, FixedVertex2D b, FixedVertex2D c)
{
FixedVector2 ab = a.GetDirectionTo(b);
FixedVector2 ac = a.GetDirectionTo(c);
if ((ab.x * ac.y - ab.y * ac.x).IsZero())
{
throw new System.ArgumentException("This set of vertices can't form the triangle");
}
}
public bool IsInTriangle(FixedVector2 p)
{
RecalculateDirectionalVectors();
FixedVector2 ap = a.GetDirectionTo(p);
FixedVector2 bp = b.GetDirectionTo(p);
FixedVector2 cp = b.GetDirectionTo(p);
Fixed bpXab = FixedVector2.PseudoscalarMultiplication(bp, ab);
Fixed cpXbc = FixedVector2.PseudoscalarMultiplication(cp, bc);
Fixed apXca = FixedVector2.PseudoscalarMultiplication(ap, ca);
//this return means that sign of the pseudoscalar multiplications is equal
return
(apXca.IsZero() || bpXab.IsZero() || cpXbc.IsZero()
||
(apXca.IsNegative() == bpXab.IsNegative() && apXca.IsNegative() == cpXbc.IsNegative()));
}