Grounded Gameplay Design

Transitioning Homeworld’s space-based gameplay to a ground-based RTS

By Elliot Hudson – Core Gameplay Designer

Before embarking on our journey to create a new Homeworld game, we reflected a lot on what made the originals unique, successful, and resonate with their audience. We had a whiteboard covered in words describing the essence of Homeworld, from the concrete (“huge ships!” “explosive battles!”) to the abstract (“loneliness”, “discovery”). We wanted to fully understand what made Homeworld great, so that we could “do the right thing” when it came to designing Homeworld: Deserts of Kharak.

In terms of gameplay, there were several aspects that jumped out at us as core to the Homeworld experience:

  • Three-dimensional movement: The freedom to choose any direction to move and attack from.
  • Mobility: A fleet constantly on the move. A deliberate shift away from traditional RTS base-building.
  • Formations: Strategically controlling the movements of a fleet. Beautiful battles.

We knew we wanted to hit all of these points. At the same time, we wanted to provide a fresh perspective into the Homeworld universe by showing life on Kharak, and focusing on the massive land vehicles which were the forerunners to the fleets of the future. What we didn’t expect was the challenges of adapting Homeworld’s gameplay to a ground-based setting.

Three-Dimensional Movement

Elevation matters in Homeworld: Deserts of Kharak

Units engaging on a hill.

In Homeworld, units can move unrestricted on the vertical axis. However, the units in DoK don’t have such freedom. In response, we found we had to challenge our understanding of map design, introducing a greater breadth of vertical space through elevations of terrain. We also made verticality more compelling through our Height Advantage system, providing accuracy and damage benefits  when attacking from above a target. Height Advantage also synergizes well with our Line-of-Fire system, which encourages players to seek lower elevations in order to gain cover.

Mobility

Carrier and fleet on the move amidst a battle.

Encouraging fleet mobility seemed easy: you have a gigantic Command Carrier which produces all your units, and it can move. Boom, case closed! Not so easy. We became painfully aware of the limitations a single mobile production unit places on RTS gameplay. If Players are not building immobile structures which must be defended, then there’s little reason to spread out their forces, and most matches turn into two giant swarms smashing into each other. Scouting also becomes less useful, whereas base-building has the benefit of hinting at an opponent’s strength and strategy. In DoK, we encourage splitting the Player’s forces by providing simultaneous objectives and points of contention across the map (more on how this happens in Multiplayer in another post!). The scouting problem is mitigated by providing signs on the Carrier itself as to what technology a Player has (such as runways on the deck lighting up when air units are acquired).

Formations

The cruiser, Armored Assaults, and Light Attack Vehicles assume appropriate formations on the move.

We agonized over formations, and it was by far the hardest thing to bring forward. We are deeply aware of the strong role of formations in Homeworld. It was easy for us to get units moving in a delta, box or circle. However, there were immediate technical and gameplay challenges.

 

We found it was extremely difficult to get formations to interact intelligently with our highly realistic and organic terrain. Moving through a curving, narrow passage turned a beautiful delta into a messy clump, ripe for a devastating explosive attack. One unit swerving to avoid a rocky outcrop caused an entire formation to slow down and wait for it. This was exacerbated by the fact that we have somewhat realistic vehicle motion; our units drive like real-world vehicles, making quick, snappy adjustments tricky. The limitations imposed by the terrain and unit locomotion would often trip up attempts to execute on formation control. Ultimately, we decided we didn’t want to make Players babysit formations that were “misbehaving”, so we designed an intuitive, automatic, context-based formation system that intelligently puts units into formation based on Player input. For example, moving a group of Railguns automatically puts them in a long line, maximizing their damage output. Setting a group to guard another unit will put them in a circle around the target. When moving groups of mixed unit types, weaker support units take up position in the back ranks, while tankier offensive units move to the front. We feel that this provides Players with control over the layout of their fleet while allowing them to focus more on moment-to-moment gameplay.

Conclusion

These were challenging design problems. We discovered that context is king, and we feel like we successfully adapted verticality and mobility to a new setting. As for formations, it was clear that Homeworld’s system worked well in space, but for a ground-based RTS with realistic vehicle physics, we needed a simpler approach that was connected more intuitively to Player action. In the end, we’re extremely proud of our ground-based Homeworld game. It feels at once akin to the originals, and utterly unique. We hope that the fans agree that it’s both a worthy successor and a fresh take on an acclaimed title.

Discussion
  1. 1.
    This is the kind of stuff I love to hear, though I probably want even more than you can reasonably give.

    I understand you can't go into too much detail, but a bit of insight into the decisions and technical aspects of the game's development, like you've given here, is much appreciated!

    Looking forward to follow on articles.

    Edit:

    In direct response to the article, problematic formation behaviour when traversing bottlenecks could've been a gameplay element!

    Though the indirect control now applied does work reasonably well, interactive group behaviour between different units isn't really apparent, other than in guard mode or forming up at the destination. Would like to have a form of movement coördination other than guarding available.

    2.
    I would love to be able to simply orient a formation of craft along a dune ridge line, much the same way I do in Total War. I wonder if that particular game mechanic is under IP license?
    3.
    astrospud you can! With a group selected, press 'V' or 'A' to bring up the feedback dial, then left-click-drag to set the facing of that group. They will assume that facing direction when they reach their destination.
    4.
    I have a question for this, did you take anything about the terrain and LOS gameplay from the Wargame series? Those RTS games put a huge emphasis on manipulating units in terrain and paying attention to LOS.
    5.






    Originally posted by BBI-ekhudson

    View Post


    astrospud you can! With a group selected, press 'V' or 'A' to bring up the feedback dial, then left-click-drag to set the facing of that group. They will assume that facing direction when they reach their destination.




    Awesome, thanks!
    6.






    Originally posted by BBI-ekhudson

    View Post


    astrospud you can! With a group selected, press 'V' or 'A' to bring up the feedback dial, then left-click-drag to set the facing of that group. They will assume that facing direction when they reach their destination.






    Was this in the tutorial?

    This really should be in the tutorial i had no idea.
    9.
    I missed it too before until you pointed it out on the Reddit, but good on you that you're spreading the word continuously.

    Maybe next time (DLC?) you'll going to add more/better tutorials? It's really a shame if we complain about a lack of features that already are in the game..