A work-in-progress collection of interface bindings to raylib 5.5, for 2-D and 3-D game programming in Fortran 2018.

Install the raylib package suitable for your operating system, or build from source:

$ cd raylib-5.5/
$ mkdir build && cd build/
$ cmake ..
$ make PLATFORM=PLATFORM_DESKTOP
$ make install

Select platform PLATFORM_DESKTOP_SDL for the SDL 2.0 back-end:

$ make PLATFORM=PLATFORM_DESKTOP_SDL

Build the fortran-raylib library by executing the provided Makefile:

$ git clone --depth 1 https://github.com/interkosmos/fortran-raylib
$ cd fortran-raylib/
$ make

Pass argument RAYLIB to override the raylib library to link. For example, if the static library libraylib.a is in the same directory:

$ make RAYLIB=libraylib.a

You may have to set the libraries to link manually (argument LDLIBS), depending on you operating system.

Building the library and all examples with fpm:

$ fpm build --profile release --flag "-fno-range-check"

Alternatively, you can add fortran-raylib as a dependency to the fpm.toml of your project:

[dependencies]
fortran-raylib = { git = "https://github.com/interkosmos/fortran-raylib.git" }

Link your Fortran application against libfortran-raylib.a, -lraylib, and additional platform-dependent libraries:

The following example program opens a window and draws some text.

! example.f90
program main
    use, intrinsic :: iso_c_binding, only: c_null_char
    use :: raylib
    implicit none (type, external)

    integer, parameter :: SCREEN_WIDTH  = 800
    integer, parameter :: SCREEN_HEIGHT = 450

    call init_window(SCREEN_WIDTH, SCREEN_HEIGHT, 'Fortran + raylib' // c_null_char)
    call set_target_fps(60)

    do while (.not. window_should_close())
        call begin_drawing()
            call clear_background(RAYWHITE)
            call draw_text('Hello, World!' // c_null_char, 190, 200, 20, LIGHTGRAY)
        call end_drawing()
    end do

    call close_window()
end program main

Compile and link the example program:

$ gfortran -L/usr/local/lib -o example example.f90 libfortran-raylib.a -lraylib -lGL -lpthread -lm
$ ./example

Depending on the build flags chosen for raylib, you may have to link with -lglfw additionally.

More examples can be found in examples/:

• bunny is a bunny benchmark.
• camera renders a cube in 3-D.
• camera3d renders a 3-D scene, with keyboard and mouse controls.
• castle renders a 3-D model loaded from file.
• collision shows 2-D collision detection.
• cubes renders waving cubes.
• explosion renders sprites and plays sound.
• flags shows window flags.
• geometric renders basic geometric shapes.
• font displays text using bitmap fonts.
• julia renders animated Julia set (via GLSL shader).
• keys demonstrates keyboard input.
• log adds a custom logging routine.
• map renders a height map.
• maze renders a 3-D maze in first-person view.
• plane demonstrates pitch/yaw/roll of a 3-D model.
• shapes renders basic shapes.
• ship rotates a 3-D model loaded from file.
• window opens a window with raylib.

Build all examples with:

$ make examples

To link against a static raylib library, run:

$ make examples RAYLIB=libraylib.a

Some issues have to be regarded when calling raylib from Fortran:

• Loading models in Wavefront OBJ format is broken since raylib 5.0 (issue).
• All procedure names and dummy arguments have been converted to snake case.
• As Fortran does not feature unsigned data types, use the compiler flag -fno-range-check to allow signed values to be written into unsigned variables where necessary.
• Make sure to properly null-terminate all character strings passed to raylib with c_null_char from module iso_c_binding or simply achar(0).
• Some variadic C functions of raylib are not bound by the interface library, like TextFormat(). In this particular case, just use the Fortran write statement instead.
• If a function returns type(c_ptr), the result has to be converted to a Fortran pointer with the intrinsic subroutine c_f_pointer() first. C char pointers may be converted with utility subroutine c_f_str_ptr() from module raylib_util, or the intrinsic c_f_strpointer() (Fortran 2023).

ISC