A proof-of-concept for building Orbiter spaceflight simulator addons in Rust

Orbiter spacecraft addon development in Rust

This project is a proof of concept for creating a spacecraft addon for the Orbiter spaceflight simulator in Rust. It uses the cxx crate creating Rust bindings for the Orbiter SDK.

Goals

The initial goal of this project is to be able to re-create the core logic from this tutorial in Rust. The source-code from the tutorial can be found in examples/Surveyor.cpp. This file exists purely as a reference and is not used during the build. Only the functions/classes required for this tutorial is currently implemented for Rust. This has been completed and it is possible to build a DLL file that can be loaded in Orbiter and re-creates the functionality of the Surveyor spacecraft to the extent shown in the aforementioned tutorial.

Implementation

The crate can now be imported and used like a library. A demo implementation can be found in src/examples/surveyor.rs. An addon module must include a struct implementing the OrbiterVessel trait. Then it must use the init_vessel! macro to generate the code that links it to Orbiter SDK. For example:

init_vessel!(
    fn init(_h_vessel: OBJHANDLE, _flight_model: i32) {
        Surveyor::default()
    }
    fn exit() {}
);

Building

1. Download/Install Orbiter
2. Install Visual Studio 2019
3. Install Rust using rustup (https://rustup.rs)
4. Install the win32 target by running rustup add target i686-pc-windows-msvc

This addon has been tested with Rust 1.57.0 and Visual Studio 2019 Commuity Edition on Windows 10. Running cargo build should build the project generate a DLL file.

Installing and Testing the Addon

Once you build the addon, you should have a file called Surveyor.dll in target/i686-pc-windows-msvc/debug/examples/. Copy this file to the Modules folder in your Orbiter installation. Also copy over the files in the Config, Meshes and Scenarios folders into the corresponding folders in your Orbiter installation. Launch the SurveyorInOrbit scenario in Orbiter and make sure that the spacecraft shows up. Pressing "L" should activate the retro thruster firing sequence.

Future

Only a limited number of Orbiter functions are now available to Rust bindings. This list will expand in the future to hopefully include all of Orbiter SDK. Pull requests are welcome!

Meshes

The meshes in the demo addon were adapted from the Surveyor 1.0 Orbiter Addon. These were updated based on the tutorial at https://www.orbiterwiki.org/wiki/Vessel_Tutorial_1.

MFDs

An older proof-of-concept for building MFDs can be found at https://github.com/thomasantony/RustMFD. However, this uses an outdated and modified version of cxx and may not build at this time and exists just as a reference. The code in that repo will be moved over to this one at some point in the future.

Notes

• Uses .cargo/config to force i686 as target