quetzalcoatlus

A Qt-based 'proving-grounds' application to exercise interesting or re-usable parts of Qt, C++17, C++ build strategies (CMake/Makefile), deployment strategies on multiple platforms, including the Docker approach for cross-compilation.

This application is an attempt to preserve the random bits and pieces of advice collected over multiple projects into a (hopefully) cohesive project.

ADD MORE!

Usage

Platforms

Tested on Ubuntu 20.04 with:

• default apt provided Qt 5.12.8
• Qt Installer provided Qt 5.15.2 ( base install path used: /home/${USER}/qt ==>> so, 5.15.2 path: /home/${USER}/qt/5.15.2 )

In general, it is recommended to use a base path like: /home/${USER}/qt or /opt/qt for installation, so it becomes easy to use the same build commands across different machines.

Get Sources

Clone the repo as usual:

git clone https://github.com/coolbreeze413/quetzalcoatlus.git
cd quetzalcoatlus

Build Local Install

For distro provided installation of Qt, we can use:

make

If we want to use a separate non-distro-provided installation of Qt, using a Qt Installer, then:

1. Ensure that we remove the CMake build directory once (if built earlier) to clear the cache and any artifacts first:

   make distclean

2. Call make with the qmake path of the desired Qt Installation to use:

   make QMAKE_PATH=/path/to/bin/qmake

   For example, if we have Qt 5.15.2 installation at: /home/${USER}/qt/5.15.2
   Then, qmake path for gcc, x86_64 will be at: /home/${USER}/qt/5.15.2/gcc_64/bin/qmake
   and then we use:

   make QMAKE_PATH=/home/${USER}/qt/5.15.2/gcc_64/bin/qmake

   For example, if we have Qt 6.5.3 installation at: /home/${USER}/qt/6.5.3
   Then, qmake path for gcc, x86_64 will be at: /home/${USER}/qt/6.5.3/gcc_64/bin/qmake
   and then we use:

   make QMAKE_PATH=/home/${USER}/qt/6.5.3/gcc_64/bin/qmake

Run Local Install

For distro provided installation of Qt, we can use:

./install/bin/quetzalcoatlus

If we want to use a separate non-distro-provided installation of Qt, using a Qt Installer, then to run the built application, set the LD_LIBRARY_PATH variable to the corresponding Qt install lib/ path:

LD_LIBRARY_PATH=/path/to/qt/install/gcc_64/lib:$LD_LIBRARY_PATH ./install/bin/quetzalcoatlus

For example, if we have Qt 5.15.2 installation at: /home/${USER}/qt/5.15.2
Then, lib path for gcc, x86_64 will be at: /home/${USER}/qt/5.15.2/gcc_64/lib
and then we use:

LD_LIBRARY_PATH=/home/${USER}/qt/5.15.2/gcc_64/lib:$LD_LIBRARY_PATH ./install/bin/quetzalcoatlus

For example, if we have Qt 6.5.3 installation at: /home/${USER}/qt/6.5.3
Then, lib path for gcc, x86_64 will be at: /home/${USER}/qt/6.5.3/gcc_64/lib
and then we use:

LD_LIBRARY_PATH=/home/${USER}/qt/6.5.3/gcc_64/lib:$LD_LIBRARY_PATH ./install/bin/quetzalcoatlus

Build deploy Package

Currently, we use linuxdeployqt for creating a deploy package and an AppImage.

Note that, linuxdeployqt will add a DT_RUNPATH( == $ORIGIN/../lib )to the ELF so that the libraries can be found without explicitly setting LD_LIBRARY_PATH while running the binary from the deploy package.

This can be seen by using readelf -d ./quetzalcoatlus in the deploy directory.

For distro provided installation of Qt, we can use:

make deploy

If we want to use a separate non-distro-provided installation of Qt, using a Qt Installer, then call make with the qmake path of the desired Qt Installation to use:

make deploy QMAKE_PATH=/path/to/bin/qmake

For example, if we have Qt 5.15.2 installation at: /home/${USER}/qt/5.15.2
Then, qmake path for gcc, x86_64 will be at: /home/${USER}/qt/5.15.2/gcc_64/bin/qmake
and then we use:

make deploy QMAKE_PATH=/home/${USER}/qt/5.15.2/gcc_64/bin/qmake

For example, if we have Qt 6.5.3 installation at: /home/${USER}/qt/6.5.3
Then, qmake path for gcc, x86_64 will be at: /home/${USER}/qt/6.5.3/gcc_64/bin/qmake
and then we use:

make deploy QMAKE_PATH=/home/${USER}/qt/6.5.3/gcc_64/bin/qmake

Internally, we set the $PATH variable to ensure that linuxdeployqt can find the correct qmake to use for packaging, according to this: https://github.com/probonopd/linuxdeployqt#qmake-configuration

Run deploy Package

deploy Package Directory

The deploy package as a directory is available at: deploy/quetzalcoatlus_<current_version>

To run from the deploy package directory, we don't need any special steps, for both distro provided Qt install or manually installed Qt installs:

cd deploy/quetzalcoatlus_<current_version>/bin
./quetzalcoatlus

deploy Package Tarball

The deploy package is also available as a tarball that can be extracted and used as the directory usage above: deploy/quetzalcoatlus_<current_version>.tar.gz

deploy Package AppImage

There is also an AppImage created: deploy/QuetzalCoatlus-${SHA1}-x86_64 which can just be run directly.

Attributions

The awesome quetzalcoatlus SVG used in the application is derived from:
https://thenounproject.com/icon/quetzalcoatlus-4818424/
CC BY 3.0
https://creativecommons.org/licenses/by/3.0/us/legalcode

The Black Hole Accretion Disk icon in the buttons is by Hrvoje Tomic from the Noun Project:
https://thenounproject.com/icon/black-hole-5551295/
CC BY 3.0
https://creativecommons.org/licenses/by/3.0/us/legalcode

The Accretion Disk gif in the application is from NASA:
https://svs.gsfc.nasa.gov/13326
Credit: NASA’s Goddard Space Flight Center/Jeremy Schnittman

The planet SVGs are derived from:
https://www.freepik.com/free-vector/flat-universe-infographic-template_6359775.htm
FreePik License