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In order to build the examples on Linux you first need some dependencies installed on your system. All of the needed dependencies are common in Linux distributions so you'll probably find everything needed through your distribution's package manager. The name of the packages vary slightly from distribution to another so you'll might need to search for the specific names a little.
The build scripts available for Linux use cmake so you have to have that installed. In addition you need a bunch of other usual build tools like gcc, libc, make and possibly others. The Linux version uses SDL so you'll also need some development packages for SDL. It's usually called SDL-devel and in order to hear sounds you'll also need SDL_mixer-devel. This is not a complete list of the dependencies so you might need to try if the building succeeds and if not then install some more dependencies. Sometimes the build process outputs a sane error message that tells what is missing, sometimes it doesn't. Good luck
This is the process I follow when compiling the examples. You may vary this to your needs if you want since cmake is quite flexible in what it can do. But it's a safe bet to follow these quidelines if you are not yet too familiar with cmake.
It's a good practice to do so called out-of-source builds. This way the compiled object and other files don't pollute the source directory but instead they are put to a directory of their own. With cmake out-of-source builds are really easy.
So fire up your console and let's start typing.
First let's make a directory where the building will happen.
cd RTBareBones/linux mkdir build
Then enter that directory, call cmake and then make.
cd build cmake .. make
The argument to cmake (..) tells where it's supposed to search for the CMakeLists.txt build file that tells it what to do. If you make your build directory somewhere else than shown above you would need to adjust this argument accordingly but other than that the process should be exactly the same as here.
If the build finishes without errors you'll end up with a binary called
rtbarebones in the build directory. In the process cmake has created a bunch of subdirectories and files but you don't need to care about these - let cmake do its stuff.
In order to run the compiled program you'll need to change to the directory which contains the images and other resources and execute the binary from there. This way the program can find the resources and load them correctly.
cd ../../bin ../linux/build/rtbarebones
Now you should see the application window.
The compilation process for the other examples is exactly the same that what was explained for RTBareBones above. But in addition the other examples than RTBareBones need resources to be built as explained here: Compiling RTSimpleApp. You can do this resource building in Linux as well. The difference is that you need to compile the RTPack tool before it can be done.
Compiling RTPack is a similar process to compiling the examples. The build script here is also for cmake. There is a helper script that chooses a correct build directory for you so that the resource building in future steps will go smoothly. Do these commands in your console:
cd tools/RTPack ./build.sh
The resulting binary called
RTPack will appear to a subdirectory called
build. Let it stay there.
Now let's build RTSimpleApp just like RTBareBones:
cd RTSimpleApp/linux mkdir build cd build cmake .. make
Next we'll build the resources. There is a helper script available that can be used in Linux to do this. There are similar helper scripts for Windows as well. The difference is that while there is a separate Windows script called update_media.bat for each example there is only one script for Linux that tries to take care of all the examples.
Run the script and see it do its job:
cd ../../media ../../tools/linux/update_media.sh
This will convert the fonts and images to correct format and copy the converted resources to the
bin directory of the example. Next you can run the example:
cd ../bin ../linux/build/rtsimpleapp
The rest of the examples can be compiled and run in a similar way.
The resource building script goes to the subdirectories of the
media directory and converts fonts and images to the Proton format. It uses a configuration file called
texture_conversion_flags.txt that contains options for converting the images. The examples'
media directories already contain these configuration files but if you'll build your own applications and want to use this system make sure you have these files in place.
The process described above for building the examples produces a binary that can be called a release build. We didn't give any special instructions for cmake so it chose the default settings. Especially the binary doesn't contain any debug symbols so it's not really suitable for a debugger. Luckily doing debug builds with cmake is quite easy.
Let's use the RTBareBones as an example. This is one place where the out-of-source builds used above come handy. You already have a release build made to a directory
RTBareBones/linux/build. You can let the release build be there and do a debug build to another directory like this:
cd RTBareBones/linux mkdir build-debug cd build-debug cmake -DCMAKE_BUILD_TYPE=Debug .. make
Now you have the debug and release builds in separate subdirectories and they don't mess with each other. You can off course have more subdirectories to different kinds of builds as you desire.
You basically only have to run cmake manually once per build directory. After that you can just run make. If the CMakeLists.txt file has been changed it is noticed by the build scripts and cmake is run automatically with the same parameters as it was run the first time.
The Linux versions of the examples accept a few command line arguments. You can choose the video mode and emulated environment (e.g. iOS, Android,…) from a predefined set of presets. You can get a list of the available modes by running any of the examples with option
[user@localhost]$ ./rtsimpleapp -l Available video modes: Windows Windows Wide OSX OSX Wide Linux Linux Wide iPhone iPhone Landscape [...]
You can choose any of these modes by giving the name of it as an argument to the program. For example testing how an application might look on an iPad you can command:
./rtsimpleapp "iPad Landscape"
Note that you need to enclose modes with spaces between quotes.
All of the tools mentioned on this page work from the command line. It means that no IDE is chosen for you beforehand. You are free to use any editor or IDE you like, be it emacs or vi or something more sophisticated.
As a personal preference I'm using QtCreator. It has a nice built-in importer for cmake projects. Although QtCreator is mainly meant for Qt development it's a great IDE for any C++ development. You can open the CMakeLists.txt file with QtCreator and it automatically imports the project in to the IDE. You might need to set some paths or such in the project settings but it's relatively easy to get the building work with Ctrl+B and running with Ctrl+R. QtCreator also has a great UI for debugger.
You can set multiple run configurations so you can run the applications with different command line arguments for example - perhaps setting a different window resolution for each configuration.