fortran-raylib

A work-in-progress collection of interface bindings to raylib 5.5, for 2-D and 3-D game programming in Fortran 2018. The library has been tested with GNU Fortran 14 and Flang 20.

Build Instructions

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

Make

Build the fortran-raylib library with GNU Fortran by executing the provided Makefile:

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

Or, to compile with Flang:

$ make FC=flang20

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 your operating system.

Fortran Package Manager

Building the library and all examples with fpm:

$ fpm build --profile release

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" }

Linking

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

System	Linker Libraries
FreeBSD	-lraylib -lglfw -lGL -lpthread -lm
Linux	-lraylib -lGL -lm -lpthread -ldl -lrt -lX11
Linux (Wayland)	-lraylib -lGL -lm -lpthread -ldl -lrt -lwayland-client -lwayland-cursor -lwayland-egl -lxkbcommon
macOS	-lraylib -framework OpenGL -framework Cocoa -framework IOKit -framework CoreAudio -framework CoreVideo
Raspberry Pi	-lraylib -lbrcmGLESv2 -lbrcmEGL -lpthread -lrt -lm -lbcm_host -ldl -latomic
Windows	-lraylib -lopengl32 -lgdi32 -lwinmm

Example

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.

Further Examples

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.
• mesh demonstrates mesh instancing.
• plane shows 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

Compatibility

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.
• 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).

Licence

ISC