Different margin on first page

Question

To meet the conditions of our corporate design I need other margins on the first page of each document. The normal page layout is given by

\usepackage[left=3cm,right=2cm,bottom=3cm,top=2cm]{geometry}

But on the first page I need

\usepackage[left=3cm,right=4.5cm,bottom=3cm,top=2cm]{geometry}

I am aware of commands like \newgeometry, but for such things I need to insert pagebreaks by hand.

How can I achieve different margins only on the first page without doing pagebreaks by hand? Any trick (like using wrapfig or something like this) is allowed.

Here is a MWE where I want to use it:

\documentclass[parskip=half,fontsize=11pt,ngerman]{scrlttr2}
\usepackage{babel,lipsum,txfonts}
\usepackage[left=3cm,right=2cm,bottom=3cm,top=2cm]{geometry}

\setkomavar{fromaddress}{Street}
\setkomavar{yourmail}{2013-01-10}
\setkomavar{subject}{Subject}

\begin{document}

\begin{letter}{Insert a name here}
\opening{Hi,}
\lipsum
\end{letter}

\end{document}

Answer 1

If you are okay with manual fiddling you can use a combination of \rightskip and \parshape. The problem with \rightskip is that it will always act on the entire paragraph, so that the first lines on the second page would still obey the wrong margin, if they belong to a paragraph that started on the first page. \parshape can handle line by line, but you need to specify the number of lines by hand (or automatize it somehow.

\documentclass[parskip=half,fontsize=11pt,ngerman]{scrlttr2}
\usepackage{babel,lipsum}
\usepackage[left=3cm,right=2cm,bottom=3cm,top=2cm]{geometry}
\setkomavar{fromaddress}{Street}
\setkomavar{yourmail}{2013-01-10}
\setkomavar{subject}{Subject}

\setlength{\rightskip}{2.5cm}

\begin{document}

\begin{letter}{Insert a name here}
\opening{Hi,}
\lipsum[1]
\lipsum[2]
\setlength{\rightskip}{0pt}
\parshape 8
0cm \dimexpr\textwidth-2.5cm\relax
0cm \dimexpr\textwidth-2.5cm\relax
0cm \dimexpr\textwidth-2.5cm\relax
0cm \dimexpr\textwidth-2.5cm\relax
0cm \dimexpr\textwidth-2.5cm\relax
0cm \dimexpr\textwidth-2.5cm\relax
0cm \dimexpr\textwidth-2.5cm\relax
0cm \textwidth
\lipsum[3]

\lipsum[4]
\end{letter}

\end{document}

I do not claim that this is a perfect solution, but maybe it gives someone else here an idea to build on.

---

Edit to point out the problems with using only \rightskip

It would be much more elegant to just reset the right margin after the first page is done. However, you then run into problems, if the second page continues a paragraph that started on the first one:

\documentclass[parskip=half,fontsize=11pt,ngerman]{scrlttr2}
\usepackage{babel,lipsum}
\usepackage[left=3cm,right=2cm,bottom=3cm,top=2cm]{geometry}
\setkomavar{fromaddress}{Street}
\setkomavar{yourmail}{2013-01-10}
\setkomavar{subject}{Subject}

% reset \rightskip to zero when first page is done
\usepackage{everyshi}
\setlength{\rightskip}{2.5cm}
\AtNextShipout{\global\rightskip=0pt}

\begin{document}

\begin{letter}{Insert a name here}
\opening{Hi,}
\lipsum[1]
\lipsum[2]
\lipsum[3]
\lipsum[4]
\end{letter}

\end{document}

The above will result in a wrong indentation of the first lines on the second page.

Answer 2

I don't have a solution for the scrlttr2 class, although I think if you beat this answer with the letter class, you should be able to get it to work ...

Something like

\usepackage{everyshi}
\AtNextShipout{\global\rightskip=-2.5cm\relax}

can handle the simple cases of single page letters and letters where the first page break occur at a paragraph. As I see it the crux of the problem is to handle the case when the first page break occurs in the middle of a paragraph. David's answer handles simple cases by defining a parshape and keeping track of where you are. This solution works great if you start the parshape at the top of a page. The problem with letters is that there is variable amounts of "stuff" at the top of the page. This is especially true for the scrlttr2 class, which is why I cannot get it to work. Butchering David's code to handle a pages with variable numbers of lines (the first page of the letter class with your margins has 54 lines) and a variable width gives

\newlength{\textwidth@wide}
\setlength{\textwidth@wide}{\textwidth}
\addtolength{\textwidth@wide}{2.5cm}
\newcounter{nlines@first}
\setcounter{nlines@first}{54}

\def\shp#1{%
\@tempcnta\z@
\loop
\advance\@tempcnta\@ne
\edef\pshape{\pshape 0pt #1 }
\ifnum\@tempcnta<\value{nlines@first}
\repeat
\advance\@tempcntb\value{nlines@first}
}

\def\reshape{%
  \begingroup%
    \@tempcntb\z@%
    \def\pshape{}%
    \shp{\textwidth}\shp{\textwidth@wide}%
    \def\par{\ifhmode\\\fi\hspace*{\parindent}\ignorespaces}%
    \parshape\@tempcntb\pshape%
}

If you never used \opening then the solution is very easy

\usepackage{etoolbox}
\apptocmd{\letter}{\reshape}{}{}
\pretocmd{\endletter}{\endgraf\endgroup}{}{}

\opening does a whole lot more than just add the opening (e.g., it adds to and from addresses and a date). To handle this, we need to undo the change to the letter environment and modify \opening.

\pretocmd{\opening}{\endgraf\endgroup}{}{}
\apptocmd{\opening}{
  \ifx\toaddress\@empty
  \else
    \expandafter\count@lines\expandafter{\toaddress}%
    \addtocounter{nlines@first}{-2}%
  \fi
  \addtocounter{nlines@first}{-4}%
  \reshape%
}{}{}
\patchcmd{\opening}{{\raggedleft\@date\par}}{\addtocounter{nlines@first}{-2}{\raggedleft\@date\par}}{}{}
\patchcmd{\opening}{\thispagestyle{empty}}{\thispagestyle{empty}\addtocounter{nlines@first}{-4}\expandafter\count@lines\expandafter{\fromaddress}}{}{}

where we define the helper function

\newcommand{\count@lines}[1]{\@count@lines@#1\\@@@}
\long\def\@count@lines@ #1\\#2@@@{%
  \ifstrequal{#2}{}{}{%
    \addtocounter{nlines@first}{-1}%
    \@count@lines@#2@@@%
  }%
}

for counting the number of lines in the "to" and "from" addresses.

Putting it all together into a MWE

\documentclass{letter}
\usepackage[left=3cm,right=4.5cm,bottom=3cm,top=2cm]{geometry}
\usepackage[nopar]{lipsum}

\setlength{\parindent}{1cm}
\usepackage{everyshi}
\AtNextShipout{\global\rightskip=-2.5cm\relax}

\usepackage{etoolbox}
\makeatletter

\newlength{\textwidth@wide}
\setlength{\textwidth@wide}{\textwidth}
\addtolength{\textwidth@wide}{2.5cm}

\newcounter{nlines@first}
\setcounter{nlines@first}{54}

\def\shp#1{%
\@tempcnta\z@
\loop
\advance\@tempcnta\@ne
\edef\pshape{\pshape 0pt #1 }
\ifnum\@tempcnta<\value{nlines@first}
\repeat
\advance\@tempcntb\value{nlines@first}
}

\def\reshape{%
  \begingroup%
    \@tempcntb\z@%
    \def\pshape{}%
    \shp{\textwidth}\shp{\textwidth@wide}%
    \def\par{\ifhmode\\\fi\hspace*{\parindent}\ignorespaces}%
    \parshape\@tempcntb\pshape%
}

\pretocmd{\opening}{\endgraf\endgroup}{}{}
\apptocmd{\opening}{
  \ifx\toaddress\@empty
  \else
    \expandafter\count@lines\expandafter{\toaddress}%
    \addtocounter{nlines@first}{-2}%
  \fi
  \addtocounter{nlines@first}{-4}%
  \reshape%
}{}{}
\patchcmd{\opening}{{\raggedleft\@date\par}}{\addtocounter{nlines@first}{-2}{\raggedleft\@date\par}}{}{}
\patchcmd{\opening}{\thispagestyle{empty}}{\thispagestyle{empty}\addtocounter{nlines@first}{-4}\expandafter\count@lines\expandafter{\fromaddress}}{}{}

\newcommand{\count@lines}[1]{\@count@lines@#1\\@@@}
\long\def\@count@lines@ #1\\#2@@@{%
  \ifstrequal{#2}{}{}{%
    \addtocounter{nlines@first}{-1}%
    \@count@lines@#2@@@%
  }%
}
\makeatother

\apptocmd{\letter}{\reshape}{}{}
\pretocmd{\endletter}{\endgraf\endgroup}{}{}

\address{W\\X\\Y\\Z}
\begin{document}
\begin{letter}{A\\B\\C\\D\\E\\F}
\opening{Hi,}
\lipsum[1-3]\par\lipsum[1-3]\par\lipsum[1-3]\par\lipsum[1-3]
\end{letter}
\end{document}

The problem with the scrlttr2 class is that \opening is more complicated, but I think if you find the height of everything that is shipped out before the letter begins, you could make this approach work. If not, you should be able to create a less general company letter head class around this approach.

Answer 3

For the simple case of a one page letter or a page break between paragraphs all we need is

\usepackage{everyshi}
\AtNextShipout{\global\rightskip=-2.5cm\relax}

Using a modified version of David's magic can handle the case where the page breaks in the middle of a paragraph.

\makeatletter
\newlength{\textwidth@wide}
\setlength{\textwidth@wide}{\textwidth}
\addtolength{\textwidth@wide}{2.5cm}

\def\shp#1{%
\@tempcnta\z@
\loop
\advance\@tempcnta\@ne
\edef\pshape{\pshape 0pt #1 }
\ifnum\@tempcnta<\value{nlines@first}
\repeat
\advance\@tempcntb\value{nlines@first}
}

\def\reshape{%
    \@tempcntb\z@%
    \def\pshape{}
    \shp{\textwidth}\shp{\textwidth@wide}%
    \def\par{\ifhmode\\\fi\hspace*{\parindent}\ignorespaces}%
    \parshape\@tempcntb\pshape%
}
\makeatother

David was careful to put this magic into a group, however, I cannot get it to work in a group inside the scrlttr2 letter environment. This means that there might be lots of unexpected side effects. It will only be used inside the letter environment group so it might not be so bad. In order for the reshaping to work requires knowing how many lines are on the first page. We can use the lineno package to do that.

\usepackage[pagewise]{lineno}
\makeatletter
\newcounter{nlines@first}
\renewcommand{\@LN}[2]{\ifstrequal{#2}{0}{\stepcounter{nlines@first}}{}}
\def\LineNumber{}
\makeatother

We then just need to patch \opening to setup line numbering and reshaping.

\usepackage{etoolbox}
\apptocmd{\opening}{\linenumbers\reshape}{}{}

Putting it all together

\documentclass[ngerman]{scrlttr2}
\usepackage{babel}
\usepackage[left=3cm,right=4.5cm,bottom=3cm,top=2cm]{geometry}
\usepackage[nopar]{lipsum}
\setlength{\parindent}{1cm}

\usepackage{everyshi}
\AtNextShipout{\global\rightskip=-2.5cm\relax}

\usepackage[pagewise]{lineno}
\makeatletter
\newcounter{nlines@first}
\renewcommand{\@LN}[2]{\ifstrequal{#2}{0}{\stepcounter{nlines@first}}{}}
\def\LineNumber{}
\makeatother

\makeatletter
\newlength{\textwidth@wide}
\setlength{\textwidth@wide}{\textwidth}
\addtolength{\textwidth@wide}{2.5cm}

\def\shp#1{%
\@tempcnta\z@
\loop
\advance\@tempcnta\@ne
\edef\pshape{\pshape 0pt #1 }
\ifnum\@tempcnta<\value{nlines@first}
\repeat
\advance\@tempcntb\value{nlines@first}
}

\def\reshape{%
    \@tempcntb\z@%
    \def\pshape{}
    \shp{\textwidth}\shp{\textwidth@wide}%
    \def\par{\ifhmode\\\fi\hspace*{\parindent}\ignorespaces}%
    \parshape\@tempcntb\pshape%
}
\makeatother

\usepackage{etoolbox}
\apptocmd{\opening}{\linenumbers\reshape}{}{}

\setkomavar{fromaddress}{Street}
\setkomavar{yourmail}{2013-01-10}
\setkomavar{subject}{Subject}

\begin{document}
\begin{letter}{My Name}
\opening{Hi,}
\lipsum[1-2]\par\lipsum[1-3]\par\lipsum[1-3]\par\lipsum[1-3]
\end{letter}
\end{document}

Answer 4

It is depreciated, but it will work for you (since you don't use memoir), the changepage package.

Simply enclose the content of the first page with \begin{adjustwidth}{<leftmargin>}{<rightmargin>} and \end{adjustwidth}, and complete with the additional margin you want on left and on right.
For your specific problem:

\begin{adjustwidth}{}{+2.5cm}
    \lipsum
\end{adjustwidth}

---

Update: If you don't know where the page ends (which seems to be the case), you can use \changepage{<text height>}{<text width>}{<even-side margin>}{<odd-side margin>}{<column sep.>}{<topmargin>}{<headheight>}{<headsep>}{<footskip>} and add margin or change text limits on the page the command appear; the margins and limits will be reset to document values on the next page.
For your specific problem it is simply:

\changepage{}{-2.5cm}{}{}{}{}{}{}{}

Answer 5

You can use the afterpage package which allows you to execute a command when a page break occurs.
For you specific problem use it as follows:

\begin{document}

\rightskip=2.5cm
\afterpage{\global\rightskip=0.0cm}

\begin{letter}{Insert a name here}
\opening{Hi,}
\lipsum
\end{letter}

\end{document}