Ran into an interesting detail concerning differences between Flex and Java, having to do with their matrix representations. If you are unfamiliar with Matrices, as I am, you can review Matrices and Transformations in Flash at http://www.senocular.com/flash/tutorials/transformmatrix/. The detail is this: Java and Flash have their second and third at the opposite to each other. So, for example, in this matrix:
In Flash, you would say:
matrix = new Matrix(a, b, c, d, tx, ty);
and in Java, it look like:
matrix = new Matrix(a, c, b, d, tx, ty);
(Well, their matrix is spelled a little differently. See the javadoc page at : http://java.sun.com/j2se/1.4.2/docs/api/java/awt/geom/AffineTransform.html
[ m00 m01 m02 ]
[ m10 m11 m12 ]
This was one thorny detail on top of the rest of the great fun of the iText library. The other interesting piece is that the y coordinates are reversed. The PDF was designed for print media, so the y starts at the bottom of the page, with increasing values as it goes up. In Flash, it is the opposite. The y origin is at the top of the screen, increasing in value as you go downward. This is all in general, and default. It is possible to apply a transformation to the PDF to reverse the Y values, and likewise with the Flash.
With the PDF, you can apply the following transofmation:
matrix(1.o, 0.0, 0.0, -1.0, 0.0, h*)
using concatCTM most likely. The d value reverses the direction of the y axis, and the h* is a special value which is on the overall height of the page. Because once you reverse the y value, it is still originated at the bottom left. But when it increases it goes off the page into oblivion. The h* value moves the origin to the upper left hand corner of the page.