public Vector InverseTransform(Vector v)
{
float x = v.x, y = v.y;
float det = m00 * m11 - m01 * m10;
if (Math.Abs(det) == 0f) {
// determinant is zero; matrix is not invertible
throw new NoninvertibleTransformException(this.ToString());
}
float rdet = 1 / det;
return new Vector((x * m11 - y * m10) * rdet,
(y * m00 - x * m01) * rdet);
}
public Vector Transform(Vector v)
{
float x = v.x, y = v.y;
return new Vector(m00*x + m10*y, m01*x + m11*y);
}
public float DistanceSq(Vector other)
{
float dx = x - other.x, dy = y - other.y;
return dx*dx + dy*dy;
}
public float Dot(Vector other)
{
return x*other.x + y*other.y;
}
public float AngleBetween(Vector other)
{
float cos = Dot(other) / (this.Length * other.Length);
return cos >= 1f ? 0f : FloatMath.Acos(cos);
}
public float Distance(Vector other)
{
return FloatMath.Sqrt(DistanceSq(other));
}
public Vector Add(Vector other)
{
return Add(other.x, other.y);
}
public Vector Transform(Vector v)
{
return Vectors.Transform(v.x, v.y, ScaleX, ScaleY, Rotation);
}
public Vector Scale(Vector other)
{
return new Vector(x*other.x, y*other.y);
}
public Vector Subtract(Vector other)
{
return Add(-other.x, -other.y);
}
public Vector RotateScaleAndAdd(float angle, float scale, Vector add)
{
float sina = FloatMath.Sin(angle), cosa = FloatMath.Cos(angle);
return new Vector((x*cosa - y*sina)*scale + add.x,
(x*sina + y*cosa)*scale + add.y);
}
public Vector RotateAndAdd(float angle, Vector add)
{
float sina = FloatMath.Sin(angle), cosa = FloatMath.Cos(angle);
return new Vector(x*cosa - y*sina + add.x, x*sina + y*cosa + add.y);
}
public Vector Lerp(Vector other, float t, Vector result)
{
float dx = other.x - x, dy = other.y - y;
return new Vector(x + t*dx, y + t*dy);
}
/**
* Returns true if the supplied vectors' x and y components are equal to one another within
* {@link MathUtil#EPSILON}.
*/
public static bool EpsilonEquals(Vector v1, Vector v2)
{
return EpsilonEquals(v1, v2, MathUtil.EPSILON);
}
public Vector AddScaled(Vector other, float v)
{
return new Vector(x + other.x*v, y + other.y*v);
}
/**
* Returns true if the supplied vectors' x and y components are equal to one another within
* {@code epsilon}.
*/
public static bool EpsilonEquals(Vector v1, Vector v2, float epsilon)
{
return Math.Abs(v1.x - v2.x) <= epsilon && Math.Abs(v1.y - v2.y) <= epsilon;
}
public Transform Invert()
{
Vector iscale = new Vector(1f / ScaleX, 1f / ScaleY);
Vector t = new Vector(Tx, Ty).Negate().Rotate(-Rotation).Scale(iscale);
return new NonUniformTransform(iscale.x, iscale.y, -Rotation, t.x, t.y);
}
