Set this matrix to be a simple scale matrix which scales the base axes by <code>xy.x</code> and <code>xy.y</code> respectively.
<p>
The resulting matrix can be multiplied against another transformation
matrix to obtain an additional scaling.
<p>
In order to post-multiply a scaling transformation directly to a
matrix use {@link #scale(Vector2d) scale()} instead.
@see #scale(Vector2d)
@param xy
the scale in x and y respectively
@return this
Set this matrix to be a simple scale matrix which scales the base axes by <code>xy.x</code> and <code>xy.y</code> respectively. <p> The resulting matrix can be multiplied against another transformation matrix to obtain an additional scaling. <p> In order to post-multiply a scaling transformation directly to a matrix use {@link #scale(Vector2d) scale()} instead.
@see #scale(Vector2d)
@param xy the scale in x and y respectively @return this