public b2Mat22 GetInverse()
{
float a = ex.X;
float b = ey.X;
float c = ex.Y;
float d = ey.Y;
float det = a * d - b * c;
b2Mat22 B = new b2Mat22();
if (det != 0.0f)
{
det = 1.0f / det;
}
B.ex.X = det * d; B.ey.X = -det * b;
B.ex.Y = -det * c; B.ey.Y = det * a;
return(B);
}
public static Vector2D Mul(b2Mat22 A, Vector2D v)
{
return(new Vector2D(A.ex.X * v.X + A.ey.X * v.Y, A.ex.Y * v.X + A.ey.Y * v.Y));
}