How to read a PDF text matrix

Question

I am writing a program to create PDF file directly from my Program. I have used the PDF Reference manual and managed to figure out everything except for 1 thing. The Text Matrix

Answer 1

The matrices used in PDFs are Affine transforms.

tm loads the parameters into:

|a b 0|
|c d 0|
|e f 1|

Where:

a is Scale_x
b is Shear_x
c is Shear_y
d is Scale_y
e is offset x
f is offset y

A good introduction can be found at http://docstore.mik.ua/orelly/java-ent/jfc/ch04_11.htm

Hope this helps someone.