// this = this * t;
public void postMultiply(Matrix2D t)
{
Matrix2D t0 = this;
multiply(t0, t);
}
public void inverse()
{
Matrix2D t = this;
inverseFrom(t);
}
public void multiply(Matrix2D t1, Matrix2D t2)
{
a = t1.a * t2.a + t1.b * t2.c; b = t1.a * t2.b + t1.b * t2.d;
c = t1.c * t2.a + t1.d * t2.c; d = t1.c * t2.b + t1.d * t2.d;
x = t1.x * t2.a + t1.y * t2.c + t2.x; y = t1.x * t2.b + t1.y * t2.d + t2.y;
}
// this = t * this
public void preMultiply(Matrix2D t)
{
Matrix2D t0 = this;
multiply(t, t0);
}