Qt qrc/rcc files

[larpon]

The format is a little hard to find any official specs for but it looks like it can be done.

Example project:
https://github.com/pgaskin/qrc

[qkaiser]

Some more info available at https://doc.qt.io/qt-6/rcc.html

The rcc tool is used to embed resources into a Qt application during the build process. It works by generating a C++ source file containing data specified in a Qt resource (.qrc) file.

@larpon do you have any sample files we could look at ?

[larpon]

I'll try and cook one up for you - here's also some of the original C++ source for handling the rcc

[larpon]

GitHub doesn't support uploading .rcc files directly - so here's a .zip with 2 common types of .rcc files included:
rcc.zip.

The .zip also contains the files for generating the .rcc files, namely the original .qrc file and the actual contents of the .rcc output - I thought these could be helpful to have.

Assuming you have the rcc tool installed (I used the rcc tool shipped with Qt 5.14.2) and the provided rcc.zip unpacked into /tmp/rcc, the target files are:

• resources.rcc - an uncompressed .rcc, generated with: rcc -binary -no-compress -o /tmp/rcc/resources.rcc /tmp/rcc/resources.qrc
• resources_compressed.rcc - a compressed .rcc, generated with: rcc -binary --compress 9 --compress-algo zlib -o /tmp/rcc/resources_compressed.rcc /tmp/rcc/resources.qrc

Just for the record: it's the included *.rcc files this request is about - not any of the other files 🙂

Additional info
The rcc tool I used only supported zlib as a compression option.
The rcc tool can generate .rcc files in different format versions - I do not know what the default version is - but I think it defaults to version 3 of the format - I can provide .rcc files in different formats if needed.

The output of running rcc -h on the command line:

rcc -h
Usage: rcc [options] inputs
Qt Resource Compiler version 5.14.2

Options:
  -h, --help                            Displays help on commandline options.
  --help-all                            Displays help including Qt specific
                                        options.
  -v, --version                         Displays version information.
  -o, --output <file>                   Write output to <file> rather than
                                        stdout.
  -t, --temp <file>                     Use temporary <file> for big resources.
  --name <name>                         Create an external initialization
                                        function with <name>.
  --root <path>                         Prefix resource access path with root
                                        path.
  --compress-algo <algo>                Compress input files using algorithm
                                        <algo> ([zlib], none).
  --compress <level>                    Compress input files by <level>.
  --no-compress                         Disable all compression. Same as
                                        --compress-algo=none.
  --threshold <level>                   Threshold to consider compressing
                                        files.
  --binary                              Output a binary file for use as a
                                        dynamic resource.
  -g, --generator <cpp|python|python2>  Select generator.
  --pass <number>                       Pass number for big resources
  --namespace                           Turn off namespace macros.
  --verbose                             Enable verbose mode.
  --list                                Only list .qrc file entries, do not
                                        generate code.
  --list-mapping                        Only output a mapping of resource paths
                                        to file system paths defined in the .qrc
                                        file, do not generate code.
  -d, --depfile <file>                  Write a depfile with the .qrc
                                        dependencies to <file>.
  --project                             Output a resource file containing all
                                        files from the current directory.
  --format-version <number>             The RCC format version to write

Arguments:
  inputs                                Input files (*.qrc).