2.5cm spacing before chapter label is not precise

[GoogleCodeExporter]

Currently, \vspace*{2.5cm} is used to add the required vertical spacing
before chapter label. However, it produces unwanted extra spacing, which is
removed by (trial-and-error) workaround below:

\vspace*{-\parskip}\vspace*{-\baselineskip}

But this workaround does not produce the expected output.

What is the expected output?
2.5cm vertical spacing between top margin border and chapter label.

What do you see instead?
The resulting vertical spacing is slightly larger than 2.5cm (around 2.6+cm)

Original issue reported on code.google.com by teohuiming on 19 Dec 2008 at 1:19

[GoogleCodeExporter]

I raised the question
[http://groups.google.com/group/comp.text.tex/browse_thread/thread/b48a02bd95a91
7b5/337c9779a70e1582
Unwanted extra spacing at top of page after \vspace*] in comp.text.tex Usenet 
group.

Thanks to Dan Luecking, for explaining the actual cause of the problem. He 
suggested
the workaround should be replaced with the following sequence:

  \vspace*{-\topskip}
  \vspace{<desired amount>}
  \vspace{-\parskip}
  \nointerlineskip

Fixed in r157.

Original comment by teohuiming on 19 Dec 2008 at 1:43

• Changed state: Fixed