Difference between revisions of "Documentation Improvement"

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====Display and Print Targets====
 
====Display and Print Targets====

Revision as of 00:25, 27 July 2021

These instructions describe the process to change the Tutorial & Concepts Guide and the Help manuals.

If you are interested in translating the documentation, you should read Translating the GnuCash Guide and Help, too.

Preface and Introduction -- What to expect

The documentation update process uses the same software management tools that are used for updating the program itself. This ensures that changes are made consistently and reliably. This includes using a version control system (VCS) to coordinate contributions from disparate sources, as well as using DocBook, a semantic markup language for technical documentation based on eXtended Markup Language (XML) for the actual edits. It also requires contributors to check their contributions for compatibility by compiling the documentation before final submission.

These aspects require that documentation contributors learn and use several specialized tools to engage the process.

The tools and the process are outlined in this page. For background on these tools, see Build Tools.

Any changes you make will be inserted into local copies of the source documentation files and subsequently transferred to the main documentation set. These source files use a special markup in XML to provide structure. Later in the process, the XML files are converted to other versions (HTML, PDF, etc.) for viewing. As a documentation support person, your task is to shepherd your modifications through all stages from start to finish.

At each stage, you must validate your changes to assure that they are both valid and have the intended effect, and you must address any errors or unexpected changes that are found.

Since your changes will be carried out by software, there is a difference determination process that identifies exactly what and where changes will be made. This process permits you to be sure that only what you intend will actually be installed. After your changes have been validated locally, you will submit your changes to the project either through a "patch," or by a git "pull request" (both of which will be explained later).

For quality control, any changes you submit will be reviewed by a developer before your changes become official. If everything is accepted without requiring further work, your changes will be applied to the main set of documentation by a developer and you will be notified of that action.

The above brief description outlines the general documentation update process.

It may be helpful to become familiar with the references given in the REFERENCES section below.

Setting Up Your System

To begin changing the documentation, you will need to set up your system with the proper software.

Required Software

You will need the following software:

  • To manage the change sequence, you will install the git version control system. See Git for more on this.
  • To edit the source files, you will need to have a text editor. Any text editor will do, as long as it can save your files without extra markup. But some editors offer Syntaxhighlighting and perhaps other specific tools for Docbook or XML.
  • To use the build system (make commands etc.) see Requirements in the README file.
  • To illustrate your text with Screenshots and Images, you can use
    • for diagrams: any SVG able drawing program like OfficeDraw (available from LibreOffice or OpenOffice),
    • for screenshots:
      • creation: the built in PrintScreen of your OS or desktop environment,
      • manipulation: The script /util/adjust-dpi.sh uses the following programs
        • identify from ImageMagick, a nice toolset to manipulate images or query their parameters,
        • awk from gawk,
        • bc from bc, but the later two are in most cases already installed.
      • maintainance: OptiPNG should be run once on new png files, also in stylesheets.
  • To control the result, you should at least have web browser.

Initial Steps

  • You will need to obtain a local copy of the files from the GnuCash repository, which is called cloning. The cloned copy is what you will work on. See git for more information.
  • To stage your changes, you will need an appropriate directory structure.
See Initializing Documentation Build Environment for more.
  • To check your changes, you will use the make utility to compile the documentation locally.
See The Make Utility for more on using and installing make.

The Documentation Change Process

To write GnuCash documentation the following steps must be completed in the order given. When executing any command listed, do not use quotations of any sort around the commands.

N.B.: The instructions below are for a non-committer preparing a patch. If you have commit privileges in the gnucash-docs repository, the git commands you use will be somewhat different. Please see Git. If you're not familiar with using git, you'll find more details on basic commands and links to documentation there as well. You may prefer one of the many Git GUIs to the command-line instructions here, especially if you use Microsoft Windows.

Create a Place to Attach and Discuss Your Changes

This can either be

  • an (existing or new) enhancement request "bug" in Bugzilla to attach your patch or
  • a pull request (PR) on github.

While the devs would prefer PR's it is up to you to decide which is more comfortable for you.

Note the bug or PR number and title
You will be listed as wanting to be notified any time there is an update to the bug. You can monitor it until it is confirmed and applied.
Ideally you would reuse type, number and title in you commit messages.

Update Your Local Copy

Since others could be making changes to the documentation at the same time you are, the GnuCash documentation process employs git to coordinate the disparate contributions. Git ensures that your changes and those of any others are incorporated efficiently into one final set of source files. See Git to learn about using git. This section assumes that you have already obtained a clone of the GnuCash repository, as outlined in Setting Up Your System.

Before you begin editing, you must make sure that your local copy is up to date and aligns with the GnuCash repository by following the instructions at An Introduction to Git.

Autotools users need to refresh their makefiles
As the source files get changed on your machine and on the remote repositories, the files
configure.ac in the top source directory and
Makefile.am in each source directory
can change. If either of these files changes, you should run autogen.sh and configure … again to make sure that this changes are incorporated. It might occur because you changed them yourself or someone else committed a change into the repository.
If you are not sure whether or not these files have changed, the safest course is to run these commands after each git pull.
Remember
These commands are issued from the build directory; if you do not yet have your build directory set up, consult Initializing Documentation Build Environment.

Identify Location for Changes

GnuCash stores documentation in one master sequence, but reformats the information in different ways for different platforms. When you build the documentation, you create a copy in final format. To make changes, you need to edit the local repository files, not the build directory files. Once you have located the correct source files, you must identify the passages that need to be changed. Your changes should roughly follow the GNOME Documentation Style Guide of the GNOME Documentation Project.

Read the documentation carefully to find exactly where your change belongs.

The English Help Manual source XML files are in

/home/$USER/code/gnucash-docs/help/C

The English Tutorial and Concepts Guide source XML files are in

/home/$USER/code/gnucash-docs/guide/C

The non-english files are in the corresponding locations with C replaced by a 2 character language code.

It may be useful to have either a printed copy or a PDF copy [3] of the documentation available for reference. The PDF is often useful, because it allows using FIND (ctrl-F) to search for key words. This can be important to assure yourself that you have covered the existing places in the documentation where the issue you are interested in has already had a mention or treatment.

Draft Your Changes

If your changes are few and easily formulated, you should be able to make your changes directly in the source XML files.

If your changes are more extensive, you may find it helpful to develop your ideas in a separate temporary text file. If you use this approach, you will need to insert your changes into the XML file(s) affected. Doing this might be easier by using a specific XML Editor. Additional resources for XML are listed in the References section for this step.

Note: Remember to edit the source files in the repository directories, not in the build directories. The various make commands (run from the build directories), will copy the files from the repository to the build directories.

The source documents are saved in the XML flavour of DocBook code, so all changes need to follow those formatting rules. DocBook enforces strict rules about tags and markup, so be sure to make your changes fit the XML tags in the manner of the existing documentation.

Note
It is not necessary to use comments to denote the start or end of your source modifications. The version control system is used to track changes.

Conventions

Examples of commonly-used tags include: chapter, sect1 ... sect5, simplelist, orderedlist, list item, para and their corresponding closing tags.

You can find a complete reference to DocBook in The Definitive Guide. Chapter 2: Creating DocBook Documents may be of particular assistance.

Since GnuCash 3.3
The documents use XInclude
<xi:include href="Help_ch_Intro.xml" />
instead of file inclusion by
 <!ENTITY SYSTEM ...>
and most other <!ENTITY ...> elements moved in the new Document Type Definition (DTD) gnucash-docs/docbook/gnc-docbookx.dtd. Each file needs now a header
<?xml version="1.0" encoding="UTF-8"?>
<!DOCTYPE book SYSTEM "gnc-docbookx.dtd">
to be syntactical correct and find the entities.

In particular, note that:

  • Wherever possible you should use the Definitions <!ENTITY name ...> from our gnc-docbookx.dtd and the base file gnucash-guide.xml or gnucash-help.xml as &name;.
  • Elements of the graphical user interface (GUI) should have the respective markup e.g.for a label: <guilabel>Accounts</guilabel>. A incomplete list of gui elements:
accel, guibutton, guiicon, guimenu, guimenuitem, guisubmenu, keycap, keycode, keycombo, keysym, menuchoice, mousebutton, shortcut.
See DocBook Guide for more detail.
ID attributes
Many elements can contain an inside of the document unique id="chapter-more-specific-context" attribute. This will serve as target for any links — internal or for #Telling the Program of a New Help Context. So each element, which is referenced from inside or outside (GnuCash's Help context) requires one. That includes also elements, for which lists a generated in some target formats: Tables, Figures, ...
Additional they can be used to name the pages of the html output: Getting_Started.html might look nicer than pt01.html.
Conventions
Lowercase, hyphenated terms, where the first stands for the chapter.
Command to grep current definitions
From the top source directory run
grep -inrF "id=" --include="*.xml" --include="*.po" help/C/
to get the list from the english help. The pattern "*.po" is currently only required for Italian.
Commands to grep current internal references
From the top source directory run
# the usual way
grep -inrF "linkend=" --include="*.xml" --include="*.po" help/C/
# some are behind URLs like https://code.gnucash.org/docs/
grep -inrF "url=" --include="*.xml" --include="*.po" help/C/ 
# Other dependencies: xinclude's href and imagedata fileref
grep -inrF "ref=" --include="*.xml" --include="*.po" help/C/
Table Titles
They should be unique, because the <book> has one <LoT> (List of Tables), which is visible in HTML.

There are more in Docbook Conventions.

Linking
Examples
Tip
If you do not plan to replace the URL by another text, use the short form <link url="https://en.wikipedia.org/wiki/URL" /> instead of
<link url="https://en.wikipedia.org/wiki/URL">https://en.wikipedia.org/wiki/URL</link>
The result is the same.
URLs
Because they will be used in several translations, put them as entities in docbook/gnc-docbookx.dtd to allow an easier update, if they change. The previous example would become
  1. docbook/gnc-docbookx.dtd:
    <!ENTITY url-wp-en "https://en.wikipedia.org/wiki/">  <!-- Append the desired topic -->
    
  2. and in your text:
    More details in <link url="&url-wp-en;URL" />.
    
resulting in
More details in https://en.wikipedia.org/wiki/URL
Textual Conventions
Do not use vague formulations
Instead of "Previous versions [...]" use "Until version X.Y[.Z] [...]".

Adding or Removing Files

If you are adding or deleting files from the documentation, for example adding a new chapter or appendix, you will need to announce it to several parts of the system to ensure that these new or deleted files get handled properly.

This are:

  1. The base XML file (i.e., gnucash-guide.xml or gnucash-help.xml). This file includes
    <xi:include href="Book_type_Name.xml" />
    
    declarations for each source file in the documentation. You must edit this XInclude list to reflect the changes you have made to the file list, where
    • Book is either Help or empty, (TODO: should be dropped)
    • type should be either ch[apter] or app[endix],
    • Name describing its content.
  2. Tell the build system about the change:
    • Autotools Add the name for your added file to or remove the name of your removed file from the file list in Makefile.am located in the same folder as the base XML file. Makefile.am must include all files listed in the <xi:include ...> section of the base XML file in its entities list.
    • CMake Add the name of your added file to or remove the name of your removed file from the file list in CMakeLists.txt located in the same folder as the base XML file.
    Note
    There are Makefile.am and CMakeLists.txt files in each of the language folders as well as in the base documentation folder. Make sure you edit the proper copy--that is, the copy in the specific language folder you have edited.
    Important (Autotools only)
    Because you have changed Makefile.am, you will need to rerun ../configure, as described in Initializing Documentation Build Environment.
  3. Tell Git to add/remove the file to/from the repository:
    git add ${MODULE}/${LOCALE}/${FILENAME} # ${MODULE}={guide|help}; ${LOCALE}={C|de|it...}; ${FILENAME}=file to add
    git rm ${MODULE}/${LOCALE}/${FILENAME} # to remove it - also from your filesystem! See 'git help rm' for other options.
    
Note
If your update adds new modules to the full set of documentation, you should review all modules in the directory in which you are working (gnucash-docs/help/C or gnucash-docs/guide/C) to determine what changes, if any, need to be made to modules outside your original assessment.

Telling the Program of a New Help Context

In gnucash/gnome-utils/gnc-ui.h are 2 important sections:

  1. Help Files:
    /** Help Files ******************************************************/
    :
    #    define HF_GUIDE         "gnucash-guide"
    #    define HF_HELP          "gnucash-help"
    :
    
  2. Links in the Help Files (id):
    /** Links in the Help Files *****************************************/
    #define HL_USAGE             "usage"
    :
    

Ask a developer to

  1. add your chapter, section, table or whatever id to the list and
  2. use it together with its HF_* as help context in gnc_gnome_help(file_name, anchor) or where else it is associated GUI elements.
Fixme
Ways to find the ids generally in the code sources?

Validate Your Changes

In every case

xmllint is used to test that your xml file has no syntax errors or incorrect references to internal sections. The program xmllint is part of the package libxml.

Tip
Some XML aware editors have a builtin Validate command to run xmllint direct on the currently opened file and jump to the first error.

The documentation build system comes with built-in rules to run xmllint. The way to invoke these depends on which build system you have chosen.

Autotools

xmllint is run by executing make check in the appropriate build directory or sub-directory. Depending on the level in the directory hierarchy you invoke make check one or more documents will be checked.

For example, if you had downloaded the documentation files to a directory called /home/$USER/code/gnucash-docs and created a build directory called /home/$USER/code/gnucash-docs/build:

  • To validate
    • all the guide xml files for only the C (English) language:
      cd /home/$USER/code/gnucash-docs/build/guide/C
      
    • all the guide xml files for all languages:
      cd /home/$USER/code/gnucash-docs/build/guide
      
    • all the guide and help xml files:
      cd /home/$USER/code/gnucash-docs/build
      
  • Then
    make check
    
CMake

xmllint is run by executing make [something-]check in the top level build directory. Depending on the [something-] part in that command one or more documents will be checked.

For example, if you had downloaded the documentation files to a directory called /home/$USER/code/gnucash-docs and created a build directory called /home/$USER/code/gnucash-docs/build:

  • To validate one or more documents, first go to the top level build directory
    cd /home/$USER/code/gnucash-docs/build
    
  • From there to validate
    • all the guide xml files for only the C (English) language:
      make C-guide-check
      
    • all the guide xml files for all languages:
      make guide-check
      
    • all the guide and help xml files:
      make check
      

So generally the check parameter to make is of the form <language>-<document>-check. You can omit <language>- or <language>-<document>- to widen the scope of the check.

Note
xmllint works by loading the main gnucash-{guide|help}.xml file of the current document's directory together with all other xml files referenced in this main file and then checks all the files.
xmllint output
  • If your module(s) are free of XML errors, then the command returns no errors or warnings (if running in a terminal) or an empty file (if redirecting output to a file).
  • If there are any errors, fix them and repeat this step until no errors are found.
  • If you are unable to fix an XML error, ask either using IRC or, see Mailing_Lists, on gnucash-devel.
Tip
After passing make check it is a good idea to also run
CMake
make <language>-<document>-pdf
or
Autotools
make pdf
The xsltproc command used there is stricter than make check with the current settings. It will
  • warn if it finds unresolved ID references and
  • abort if a table row has more columns than declared.

After Adding, Moving or Deleting Files

Verify a tarball can be built
cd ${BUILDDIR} # Adjust this
make distcheck
and contains your new files.

After success you can remove gnucash-docs-5.9.tar.gz from your ${BUILDDIR} again.

Ensure Only Expected Changes Have Been Made

You should double check that there are no accidental changes to the documentation.

The following command will show any changes to unstaged files

git diff

Git status will list all files with differences to the last commit, in categories staged, unstaged, and unknown to git but not matching an ignore pattern.

git status

Proofreading

After you have tested the integrity of the XML using xmllint (make check) and have verified that the difference file shows the correct changes, it depends on your OS/installed software, how to proceed

Not very fast, but simple under Linux
run Gnucash after installing your version of the documentation:
Install and run your version
cd ${BUILDDIR} # adjust this
sudo make install
gnucash
#choose a component from the Help menu
This is also the preferred method to test the context sensitive help.
Fast under Linux, but more typing
KHelpcenter and Gnomes help viewer yelp can both display docbook documents:
yelp /usr/local/share/gnome/help/gnucash-help/C/gnucash-help.xml # adjust:
# 1. $PREFIX (/usr/local/) or just use your ${SOURCEDIR},
# 2. $LANG (/C/)
# 3. document help or guide

# or after we fixed the path for our DTD:
khelpcenter /usr/local/share/gnome/help/gnucash-help/C/gnucash-help.xml
# If we create .desktop files this will become easier.

In HTML and Other Formats

The easiest way to check your changes is to view the HTML version in your browser. You should also review other formats as they have their own peculiarities:

  • If you are using non-latin writing, are the fonts right in pdf?
  • Are images displayed correctly?
  • Is the page layout OK in ebooks?

The Guide or Help must be recreated in HTML and the results examined in your browser to verify that the online version appears and reads as expected.

Build the Guide or Help file in HTML. Use this command exactly as written in a terminal, from the appropriate directory within the build directory structure:
cd [appropriate directory or sub-directory within the '''build''' directory structure]
make html # Replace html  by pdf, epub, mobi ...

The above make command will run xsltproc and use an XSL stylesheet (.../xsl/general-customization.xsl) to turn the raw input XML into the output HTML that comprises the online version of the Guide or Help.

The built html files with be placed in an automatically created directory, which if using the example directories will be:
/home/$USER/code/gnucash-docs/build/<guide|help>/C/gnucash-<guide|help>

Review the results in your browser. Calibre is a good choice as viewer for ebook formats (epub, mobi, ...).

If you need to make changes, do so, then check, rebuild and review again. It's amazing how errors which are obscure in XML--everything is obscure in XML--become blindingly obvious when rendered in the browser. Look for spelling errors, formatting oddness, incomplete tags, and missing or incorrect entities.

To view the results in a web browser, in a file manager (or for Windows: Windows Explorer/File Explorer) double click on either:
/home/$USER/code/gnucash-docs/build/help/C/gnucash-help/help.html
# or
/home/$USER/code/gnucash-docs/build/guide/C/gnucash-guide/index.html

Once your inspection shows that the online Guide/Help is now acceptable in all respects, you should make certain that the build directory and its contents are not included in any respect in your patch.

If you are using build as the name of your build subdirectory in your repository directory, as in this example, it is not necessary to remove the build directory as the <repository>/.gitignore file includes build*, so git will ignore it.

To remove the build directory structure, before building the patch, use this terminal command:
rm -rf "/home/$USER/code/gnucash-docs/build"

Add Extra Files

Git automatically tracks changes to files it knows are part of the repository. However, if you have added any files that should be included in your commit (xml or others, for example, illustrations), add (stage) them with the command:

 git add path/to/file
 

Note: Do NOT add file(s) from your build directory structure.

Here is another way to check your changes. Unless you're a programmer, you're probably not well practiced at examining diffs. If you have touched several files, the first thing to check is

 git status -uno

The -uno tells it to show only the repository files affected by your changes; all of the build products are ignored. Of course, if you've made a new file, that's ignored too, so make sure that all of the files you worked on and only those files are in the list. You can add new files with

 git add path/to/new-file

and revert files that you didn't mean to change with

 git checkout path/to/ignored-file

Publish your Authorship

The first page, which can also be shown as About of the document is in the file gnucash-{guide|help}-C.omf. OMF means Open Media Framework. Add a maintainer section with your data and check the other items like the date, which also needs an update.

Add your name and email address to the file AUTHORS. Create a separate patch for this change and ask to apply this patch also on gnucash/DOCUMENTERS - in both maint and master branches. The AUTHORS file can usually be shown in the packet manager while gnucash/DOCUMENTERS is shown in GnuCashs About->Credits->Documenters

Commit Your Changes

Once you're satisfied with your changes, it's time to commit them. You can commit everything that's been changed with

git commit -a
(-a also causes git to notice and commit any deleted files)

or you can commit a few files at a time with

git add path/to/file
git commit

If you need to make further changes, you can update your commit instead of creating a new one with

 git commit -a --amend

But --amend should only be used as long, as you did not publish your commit by pushing it to some public github repository.

There are even finer-grained ways to pick out bits and pieces to group into a commit, but they're beyond the scope of this tutorial.

When you make a commit git will open a screen editor; which one depends on how you set your environment. The default on most Unixes is vi, but you can select a different one with the $EDITOR environment variable. Use the editor to make a good commit message. It should have a one-line (< 80 character) summary followed by a blank line, and a brief description of the change and its motivation. Don't get carried away here: If you need more than a couple of lines it should have been a smaller change.

The release announcement comes from commit messages, so include any information that should be passed on. You could even say This needs to be mentioned in the release announcement followed by the text you want in the announcement.

To add extra information to a previously pushed commit message, make some trivial change to a comment and write a commit message using the same subject line as the previous commit.

If required, you can check committed changes to a particular file with

 git log -p path/to/file

Create a Pull Request or a Patch

Once you have finalized your changes, you will notify the developer team of your changes, either by creating a pull request, or by creating and uploading a patch.

References to Supporting Technologies Used

[1] https://wiki.gnucash.org/wiki/Bugzilla
[2] https://github.com
[3] http://www.jedit.org/
[4] https://en.wikipedia.org/wiki/DocBook
[5] https://www.docbook.org/ DocBook: The Definitive Guide
Some Distributions have it as a package named like docbook-tdg.
[6] https://www.tldp.org/LDP/LDP-Author-Guide/html/tools-edit.html
[7] https://www.netlingo.com/tips/html-code-cheat-sheet.php
[8] https://wiki.gnucash.org/wiki/Git

Additional Information

Screenshots And Other Images

Desktop Themes for Screenshots

Try to maintain consistency with existing images by using specific themes for your desktop environment.
Most current images are still from the GnuCash-2 series, where we used the Clearlooks engine, which has been the default theme of GNOME 2 since version 2.12.
So for GnuCash3+ we should use Gnome3's default theme "Adwaita".
If you are not on Linux, try to find a similar theme for your desktop.

Image Formats

Screenshots
are ideally submitted in .png format.
Tip
Before capturing
Shrink the window size to the minimum to get the best result. If text gets truncated, file a bug against the GUI.
While capturing
Hold down the Alt keys because GTK3 else hides the accellerator markings _.
Graphics showing relations
are best in .svg. That would allow translators to replace in their copy the labels with their translation.
Callouts
images with annotations – are ideally created in GIMP's .xfc format with the
screenshot
on the first level and
each label
on a separate level.
That would again faciliate the work of translators: they can replace the screenshot and translate the labels. Finally add it in
xfc
for future maintainance and
png format
to use in the docs
to the repo and link the png in the text.
Icons
are used in all components: Program, Bundles, Documentation and Website. Best practise still needs to be written.

Indexing

To add your image to the List of Figures at the start of the Help or Tutorial and Concepts Guide, put your screenshot in a figure tag, for example:

  <figure pgwide="1">
    <title>This text will appear as header and in the List of Figures</title>
    <screenshot>
      <mediaobject>
        <!-- insert the imageobjects here -->
        <caption><para>Optionally you can here add a longer description than in the title.
          If not required, remove the caption element.</para>
        </caption>
      </mediaobject>
    </screenshot>
  </figure>
textobject
Older parts have mistakenly a <textobject> instead of a figure title or a <caption>. For now move the content into the adequate tag. Only if you want to support
add a precise description of the image as textobject.
Finally check your entry in the index context
Build the html flavour and open its Table of Content. That is currently
guide/C/gnucash-guide/index.html
help/C/gnucash-help/help.html
in your build directory, but willl change with GnuCash docs should follow XDG help-system-spec..
Scroll down to List of Figures. Is it
  • unique and
  • descriptive?

Display and Print Targets

FixMe
In between 510px on screen seems to have become too small. Rethink the numbers! On a "Full HD" monitor the normal page wide in yelp seems to be >=800px—compare different broad images.

Screenshots and images added to the GnuCash documentation must fit two purposes: video display (e.g. online) and paper printing (pdf creation). Each has its own way of determining width:

video display defines image width limits in terms of pixels, while
print output sets limits on image size based on a ratio of image size and the image's dots per inch (dpi).

Because we do not want to shrink the image itself, but want limit the width of

image presentations on screen to 510px,
and 14 cm on paper, we get 2 different cases for our entry:
width <= 510px
and insert:
      <imageobject>
        <imagedata fileref="figures/Report_Screen.png" format="PNG"
                   srccredit="your name" />
      </imageobject>
width > 510px
Use two <imageobject> tags, as shown below:
      <imageobject role="html">
        <imagedata fileref="figures/Help_Pref_AccntPeriod.png" format="PNG"
                   srccredit="your name" width="510px" />
      </imageobject>
      <imageobject role="fo">
        <imagedata fileref="figures/Help_Pref_AccntPeriod.png" format="PNG"
                   srccredit="your name" />
      </imageobject>
The "html" attribute refers to display presentation on screens (the width is limited to 510px), while the "fo" attribute refers to pdf printing.
Notes
  1. The attribute format is only required, if it is not already the filename extension. See also: docbookxsl GraphicSelection, docbookxsl GraphicFormats
  2. If the viewport area (width|depth) is specified, but no content area (contentwidth|contentdepth), docbook sets scalefit=1 resulting in zooming the image to viewportsize.

Now the image will fit on display and we can continue to adjust it for printing.

Adjusting an Image's Dots Per Inch

You must take another step to prepare a screenshot for print output: you must set the dots per inch (dpi) correctly. The dpi defines an image's dot density, and thus its overall quality; the higher the dpi, the better the printed image quality. The printing size, dpi and image pixel dimensions are in this relation:

size = pixels / dpi
So if you have a screenshot that is 800x560 pixels with a dpi of 80 you will have the screenshot in the pdf output displayed as 800/80 x 560/80 inches = 10 x 7 inches = 25 x 17.5 cm. (1 inch is about 2.5 cm). The available space in the A4 format pdf output is a maximum of about 15 cm, so you can resize the screenshot by changing its dpi (Note that the US Letter size paper is slightly wider than A4, so images scaled for A4 will also fit on US Letter size paper). Normally if you take a screenshot when the GnuCash window is almost at its minimum, the dpi will be set to 144, which for our example screenshot will result in a print size of:
800/144 x 560/144 inches = 14 x 10 cm 
This will stay inside the available areas.
If the screenshot you are going to add to documentation is wider than 850 pixels, you should increase the dpi above 144 so that its printed size remains less than 15 cm.
Tip
To query the properties of the existing images you can use Imagemagick
# for many details of one file:
identify -verbose $FILENAME
# or important infos about all files in the current directory:
echo "size and pixels per inch (dpi) of all files in the current directory:"
for i in *; do identify -format "%w x %h %x x %y" $i; echo " $i"; done;
Individual
The dpi of an image be changed in one of two ways:
  1. Open the screenshot in an image editor (like The Gimp) and select Image->Print Size. In the dialog that opens, set the X and Y resolution to the desired dpi (check that the unit value is set to the desired value - normally pixels/in). Press "Ok" and save the image.
  2. A faster approach uses Imagemagick, a library for image manipulation. From a terminal window, issue the following command:
    convert -units PixelsPerInch -density DPI IN OUT
    
where DPI is the desired dpi value (e.g. 144), IN is the input image filename and OUT the output filename (that could be the same as IN).
All at once
New Method
For your convenience the bash script adjust-dpi.sh has been included in the gnucash-docs repository that automatically calculates and assigns the right value of dpi to a list of png files. It is stored in the util subdirectory of the repository. To use it open a command line and run the script from the proper figures directory. For example:
cd guide/pt/figures            # In the repo, NOT the build directory structure
../../../util/adjust-dpi.sh
If that fails i.e. because dependencies are missing on your computer, you can still use the old methode.
Old Method
To convert the dpi of a bunch of images do this from a terminal window:
ls *.png > list
for i in `cat list`; do convert -units PixelsPerInch -density 144 "$i" "$i"; done
The first line creates the file "list" with a list of all png files in the current directory
The second and third lines applies a dpi of 144 to all images listed in the "list" file

Optimize the Compression

The tool OptiPNG tries to minimize the size of png files lossless:

cd guide/pt/figures            # In the repo, NOT the build directory structure
optipng ${FILENAME}

If it is too hard for you, ask the developers in your pull enhancement request to do it for you.

Maintenance

In this section are collected all the standards used to work on documentation.

Text conventions

  • Use the official Gnucash terminology. it is defined in
English
  1. gnc-glossary.txt
  2. and run
    make pot
    
    in your Code clone or as fallback use the current template from https://translationproject.org/domain/gnucash.html.
Other languages
<LANG>.po in
  1. https://github.com/Gnucash/gnucash/blob/maint/po/glossary/ and
  2. https://github.com/Gnucash/gnucash/blob/maint/po/
All
for GUI elements https://developer.gnome.org/hig/stable/
e.g. for future changes to revision numbers, docbook/gnc-docbookx.dtd defines variable vers-stable
<!ENTITY vers-stable "5.9">
and guide/appendixa.xml uses this variable like
The process works on &vers-stable; datafiles, and ought to ...
  • Use the same indentation as existing parts, i.e. indent each level of <tag>s by 2 spaces. Avoid the use of tabulators as their wide is not really defined and so the display of tabs varies depending on the editor, github, ...
  • Common markups - refinement in progress:
block
<task> should be used for tutorial lessons:
<procedure> is better than <numberedlist>;
<glosslist>, <varlist> are better than <itemizedlist>;
inline
All accounts named must be tagged with <emphasis>: e.g. <emphasis>Expenses:Tax</emphasis>
Use <emphasis> only as emphasis.
GUI elements. <guibutton>, <guilabel>, <menuchoice> …
In- and output: <userinput> (also for creating list elements) often combined with <replaceable>;
<computeroutput> (also selection of a list element)
<command> for console commands inline;#
<programlisting>, <screen> for complexer forms or data files can have a language attribute, which produces in yelp syntaxhighlighting.
  • Hyphens and dashes:
See https://www.thepunctuationguide.com/index.html for guidance on using English language punctuation, including &ndash; and &mdash;.
To represent a negative number or subtraction:
The typographically correct symbol to use is − (U+2212, &minus;). The ASCII hyphen-minus - (U+002d) is commonly used and is also fine. Whichever you use, be consistent, at least on the whole page.
Examples:
Number negative 1 (−1): &minus;1
Formula GROSS_SALE − TOTALBUY: GROSS_SALE &minus; TOTALBUY
  • In the current state of this page there are many more. Have a look at the recently reworked chapters. If you have some free time, add them here.

Content Checklist

Some often missed parts:

  • In which context does it get used and why - hint: why did you develope it?
  • Under which circumstances should it not be used, if any exist?
  • Do alternative methods exist?
  • The meaning of each GUI element should be explained.
  • Link related parts.

Graphics conventions

All screenshots of the GnuCash windows should be captured under the GNOME desktop environment with the following settings:

  • GNOME desktop environment
  • For GTK3 Adwaita is the default theme. Under GTK2 it was Clearlooks as you can see on older sceenshots.
  • GTK3: text below icon, before it was besides icon;
  • font: Sans. 9 point for application and 11 point for window title.
    Tip for Linux users
    Create a separate user account with above settings. That requires installation of the program for all users.
Notes
  • If the title of the window is not important, you can set without [window] decoration in your screenshot app. this will probably allow the use of other themes.
  • As GnuCash normalizes the order of transaction splits (debits before credits), you should capture the screen before finishing the transaction, in case you enter credits first.[1]

Updating Stylesheets

Sometimes maintainers update the XSL. If you do it, #Optimize the Compression of it's images.
  1. https://bugs.gnucash.orgshow_bug.cgi?id=798143 - Different order of splits in instructions and screenshot