What’s up survivors? As the topic states today’s post is going to be about engines, design decisions and various problems concerning their usefulness and implementation. So, what’s so problematic about the engines and why haven’t we covered this topic earlier? Well, there are several issues: realism, orbital mechanics and multiplayer nature of Hellion. We’d like to use this opportunity to go over them in detail.
As several players have noticed already we had done a bit of “ninja” tweaking of the main engines in Hellion. We have reduced their acceleration from “OMG” to something slightly more manageable like 200m/s2. Let’s disregard realism for a moment and say that human bodies can somehow withstand a prolonged exposure to forces exceeding 20G and let us factor in the largest problem of space exploration – distance between celestial objects. For this occasion, we will use Bethyr and its closest neighbor Eridil. Even in a scaled down model of a star system the closest distance between them is around 217,801,845 km, or 1.46 AU.
Any vessel using conventional propulsion would take around 90 days to complete the trip, moving at a constant speed of 28km/s. Now let’s use something “less realistic” like an “Epstein Drive” from The Expanse series. At a constant acceleration of 0.5G the journey would take almost 5 days. Finally, let’s check out the “completely unrealistic” engines of Hellion. With a steady thrust of 20G the journey would take over 18 hours. This may not seem as much in real terms, but for a game it is simply too long. This is why games like old Elite, Kerbal Space Program and Orbiter use “time acceleration” mechanics. However, Hellion is a multiplayer game, so playing with “time scale” is impossible. To bypass this, all long-distance travel in Hellion is done using Warp Drive.
Other space sims ran into similar problems when dealing with realistic distances and real-time nature of multiplayer and most of them have two or three different propulsion methods: Thrusters, Quantum Drive and Jump Drive in Star Citizen, engines, super cruise and Hyperspace in Elite Dangerous, or standard propulsion, LDS and Capsule-Drive in Independence War 2. In Hellion this matter is further complicated by the use of realistic orbital physics. Anyone who has played KSP or Orbiter is familiar with how difficult and time consuming it is to intercept an orbiting object.
Initially we wanted to implement a realistic engine system that would be used instead of a Warp Drive to change orbits and reach “nearby” objects. Unfortunately, this system proved overly complicated and extremely time consuming, with orbital maneuvers requiring hours and days to execute. Thus the original idea was scrapped and the engines were fully replaced with Warp Drive.
Now that we’ve pulled this idea from our backlog, we are re-working the engine controls for easier thrust adjustment to allow players to use them like “afterburners” or linear “high-speed” RCS. Overall the new control scheme should make approaching objects up to 200km away easier. Another thing we are considering at the moment is the use of engines from the Nav Map along with implementing several indicators for orbital adjustments.
Since this is still a work in progress, we are very interested in hearing your opinion on the subject of engines. So let us know what you think in the comments below and feel free to start/join a discussion on the forums.
Until next time, fly safe!
Zero Gravity team