How to load XML locale file natively - c++

I'm building a game with SFML and I'm looking for a way to localize it. I've seen many topics saying that XML is a good file type to write localization for programs. However in most examples they simply say how to write the XML file or how to load it with GUI managers such as Qt, but I'm not using any of those. What I need is the actual way to load those language files based on the system language, preferably a cross-platform way. Statically compiling and loading one language would kind of defeat the purpose of localization.

Well I decided to use a configuration file instead. I implemented a xml parser sucessfully for both the config file and the language files. I kept the setlocale function only if the user specifies that he wants his system language, might be set to that by default and if the locale fails, the user can change the config to any language.

Related

Good way to maintain Qt labels and text on UI

What is the best way/common practice for maintaining all string resources found on a UI in Qt, especially the textual input/text in combo boxes etc. (since these are the once that are frequently used in the code itself)?
I know that Android has this string resources thing such that resources only have to be modified at one position.
Does Qt have something like that too or do I have to initialize string resources in code instead of in the UI's XML itself...
AFAIK, there is no built-in mechanism for string resources in Qt. If you want to maintain strings at build time you can define them in one .h/.cpp file as global variables and reuse them in your code.
Otherwise you can use Qt's translator files (binary) and load them along with your application. If you need to change a string, you simply will need to edit the translation file (xml) and "recompile" it with lrelease utility without building the application again.
There is a mechanism to dynamically translate texts in application, but it works a bit different than Android string resources, but achieves the same goals.
Qt uses i18n system modelled after standard, well known unix gettext. It works in a very similar way to iOS NSLocalizedString, if that rings a bell.
http://doc.qt.io/qt-5/qobject.html#tr
This is worth reading too:
http://en.wikipedia.org/wiki/Gettext
http://doc.qt.io/qt-5/internationalization.html
Android approach is a bit unique and you should not expect it to be a "standard everywhere". It works, it's ok, but it's not a standard way of doing things on desktop.

C++ reading from .lang files with locales

I am creating an OpenGL game and I would like to make it open to more languages than just English for obvious reasons. From looking around and fiddling around with the games installed on my computer I can see that locales play a big part in this and that .lang files, such as en-US.lang that is shipped with minecraft, are basically text documents with a language code, "item.iron.ingot" for example, an equal sign, and then what it means for that given language, English as per en-US, so in this case would be, "Iron Ingot". Well I created a file that I named en-US.lang and this is its contents:
item.iron.ingot=Iron Ingot
In my C++ main method I put:
setlocale(LC_ALL, "en-US");
After including the locale header file. So I suppose the part that I am confused by is how to use the locales to read from the .lang file? Please help SO and some example code would be appreciated.
C++ Does not come with a built-in support for resource files / internationalization. However there is a huge variety of solutions.
To support multi-language messages, you should have some basic understanding of how such strings are encoded in files and read to memory. Here is a basic introduction if you are not familiar:
"http://www.joelonsoftware.com/articles/Unicode.html"
To keep and load the correct text at runtime you need to use a third party library: GNU gettext http://www.gnu.org/software/gettext/ is one such example. However there are other solutions out there.

Small library for generating HTML files in C++

Is there a library that will allow easier generation of a simple website using C++ code. This 'website' will then be compiled into a CHM help file (which is the final goal here). Ideally, it will allow generation of pages easily and allow links to be generated between pages easily. I can do this all by hand, but that is going be very tedious and error prone.
I know about bigger libraries such as Wt, but am more interested in smaller ones with little or no dependencies and a need for installation.
You can try CTPP template engine. It is written in C++ is small and quite fast.
Do you need this project to be written in c++? Because if you just need to prepare documentation in CHM I would go with Sphinx. Sphinx is a set of tools written in Python that generate manuals in few formats (chm, html, LaTeX, PDF) from text files (formated using reStructuredText markup language). Those text files could be created by hand or using some application and then combined into one manual using Sphinx. In my work right now we are using this solution to write documentation, because it is very easy to maintain text files (merging, tracking changes etc.) than for example html or doc. Sphinx is used to generate Python language documentation (chm), so it is capable to handle really large project.
I've used the FLATE library every day for ten years and it works flawlessly. It's a piece of cake to use; I can't recommend it enough.
It will definitely do the trick, though probably at a much lower level than you have in mind. It is a C-language source library that you can link with a C++ caller. It's also available as a Perl module, but I haven't used that.
FLATE library
Flate is a template library used to deal with html code in CGI applications. The library includes C and Perl support. All html code is put in an external file (the template) and printed using the library functions: variables, zones (parts to be displayed or not) and tables (parts to be displayed 0 to n times). Using this method you don't need to modify/recompile your application when modifying html code, printing order doesn't matter in your CGI code, and your CGI code is much cleaner.
HTH and good luck!
Are this CHM lib and the related links what you're looking for?

Is there some common way to write and read config files?

I need my program to create and edit a config file, which would contain information about set of objects, and than read it at every execution. Is there some sort of guideline for config style that i can use?
I'm using C++ on windows.
I recommend checking out boost::property_tree.
The Property Tree library provides a data structure that stores an arbitrarily deeply nested tree of values, indexed at each level by some key. Each node of the tree stores its own value, plus an ordered list of its subnodes and their keys. The tree allows easy access to any of its nodes by means of a path, which is a concatenation of multiple keys.
Additionally, it contains parsers and generators for XML, INI, and JSON, so you can save/load in the format of your choice.
It largely depends on the language, platform and the scope of your config files. There's for example the properties files in Java world for configuration, and others already mentioned here such as YAML.
XML is generally frowned upon for configuration, since it's very verbose. You still find it in many applications, Web frameworks, etc.
I think the best practice would be to choose the right configuration format for the job at hand. You can evaluate and try them for yourself, while considering these pointers:
What's the standard? (e.g. ini files in Windows, properties files in Java)
Is there native support in my language, or do I have to roll my own implementation?
Can my configuration format easily describe what I want to store as configuration?
I'm sure you could think of other considerations. If you update your question to clarify the scope, you'll get more useful answers.
YAML is a very popular solution for creating configuration files. It is used prominently by Ruby on Rails and Google AppEngine, for instance. YAML libraries are available for many if not most languages.
If you're working with Qt (based on your other questions),
look at the QSettings class. I've been using these to set a lot of persistent info, such as last visited directory, and which options were last used.
boost::program_options has some capacity to read ini files.
What is nice is that is allow to unify reading ini file and command line options. As Windows program goes, that may not be seen as such an interresting future, but for my unix app it was a killer feature.
However, boost::po does not allow editing or writing of ini files, hence you'll probably be better off with boost::property_tree.
The most common format is the INI File format. Most mdoern languages should have something built in to handle these, otherwise I'm sure you'd be able to find a third-party library.
Failing this, you could use XML, and if your language supports it, serializing to and deserializing from these XML files. If you don't want to/can't use XML, most languages will have a default format they use, such as a pure binary dump of the data in an object.
There is a free, cross-platform library for configuration file management, called libconfig. It supports very nice Yaml-based grammar, and supports user-defined grammar too. It also has many other computing language bindings. See it's homepage: http://www.hyperrealm.com/libconfig/ .
In the Java world, a properties file is pretty easy to use:
http://java.sun.com/j2se/1.5.0/docs/api/java/util/Properties.html
The Properties class represents a persistent set of properties. The Properties can be saved to a stream or loaded from a stream. Each key and its corresponding value in the property list is a string.
As the others have said, you would need to describe your environment to get the best recommendation.

Help programmatically add text to an existing PDF

I need to write a program that displays a PDF which a third-party supplies. I need to insert text data in to the form before displaying it to the user. I do have the option to convert the PDF in to another format, but it has to look exactly like the original PDF. C++ is the preferred language of choice, but other languages can be investigated (e.g. C#). It need to work on a Windows desktop machine.
What libraries, tools, strategies, or other programming languages do you suggest investigate to accomplish this task? Are there any online examples you could direct me to.
Thank-you in advance.
What about PoDoFo:
The PoDoFo library is a free, portable
C++ library which includes classes to
parse PDF files and modify their
contents into memory. The changes can
be written back to disk easily. The
parser can also be used to extract
information from a PDF file (for
example the parser could be used in a
PDF viewer). Besides parsing PoDoFo
includes also very simple classes to
create your own PDF files. All classes
are documented so it is easy to start
writing your own application using
PoDoFo.
iTextSharp is a free library that you can use in .Net applications. Take a look at the iText page - that is for the iText project, which is a Java library. iTextSharp is part of that project, and is a port to C# and .Net.
Consider Python It have a lot PDF librarys (both creating and extracting) eg:
http://pypi.python.org/pypi/pdfsplit/0.4.2
http://pypi.python.org/pypi/JagPDF/1.4.0
http://pypi.python.org/pypi/pdfminer/20091129
http://pypi.python.org/pypi/podofo/0.0.1
http://pypi.python.org/pypi/pyFPDF/1.52
There are also good tools for using C/C++ code in Python and to create .exe form Python scripts. If you decide to use different language consider Python as prototyping language!