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Who: Sara Vogl
Lucid Trips is made by an indie team of four people that started as a free time project of two of the founders from the German VR Nerds Collective, Nico and Sara. Both have a Communication Design background and got into VR and Unity due to the Rift DK1.
With Julian and Basti joining the group they got support on the coding side, and a team that was capable of adapting the rough prototype to the rapidly changing hardware was formed. Lucid Trips is the first game the team has released on Steam. The style was developed as a fusion of our motion design background and the deep connection to art of the creatives leading the group.
What: Pulling yourself through a VR world
Locomotion in VR is still a topic that is far from being sophisticatedly solved. We tried our own approach to (hyper)naturally and most intuitively move as a bodiless consciousness in virtual space even before the question of VR movement was all over the place.
The concept of locomotion of Lucid Trips has similarities with the movement of astronauts in outer space who have jetpacks attached to their wrists. Your body hovers over the ground and you alternately use your hands to move forward. Think of your body as sitting on a hover board like in the movie Back to the Future.
Though the project is still in early access, using the hand-walking method doesn’t have many difficulties with regards to motion sickness. As soon as the player develops a feeling of how the avatar reacts to the unknown surrounding, he can move around very intuitively. All movement is skill based and develops over time.
Every real-world movement is followed by a predictable movement in VR that relates to the added force. As these actions are done while your whole wrist is in movement and not only your fingers, the brain seems to be less confused by the triggered moves.
Inspired by Lucid Dreams
Lucid dreams are dreams in which you are aware that you're actually dreaming. The dream to fly is deeply rooted in the history of mankind such as being weightless and able to see perspectives like a bird. Lucid Trips immerses you to intuitively experience a whole other consciousness. As soon as you figured out how your new body reacts to the surrounding you have a very intimate and meditative experience as an undefined being in a surreal realm.
For moving around fluently and avoiding motion sickness it is crucial to have an understanding of the mechanics going on in the brain while experiencing motion and adapt to what is comfortable. On regular 2D games with gamepad you hit a button to execute a movement repeatedly, which is a bit similar to sitting in a car or other cockpit in the real world. That’s contrary to independent locomotion in the real world where for every action you do with your own body there has to be added a certain force of which we are mostly familiar with triggered response and acceleration.
As we can assume the outcome of our added force, our brain predicts the next movement and acceleration fairly well and we feel fine doing so. We made a similar observation with our hand walking technique when people got used to the controls and movements started to become very tactile and precise.
The invention of solid and affordable roomscale systems like the HTC Vive brought us a huge step forward to the potential of direct, realistic and fully immersive interaction while being close to moves you would do in reality.
In the very popular title Job Simulator from Owlchemy Labs you can experience that phenomenon of realism through interactivity. If you want to naturally move forward, you use your legs for doing so and techniques like redirected walking, where the game tricks the user into running in circles while they think they’re going straight, help a bit with not hitting walls. More clunky approaches that are often used are the Teleportation Mechanic or Omnidirectional Treadmills.
Capturing and transferring the players motion directly to his avatar definitely enhances immersion. There are different motion tracking methods available but most are very complex and expensive. Even if these systems get more and more advanced and affordable, we are still facing the currently very well known problem of locomotion in VR - being limited by the real world space around you.
New approach on Movement in VR
The concept of Lucid Trips completely avoids these problems by creating a living room friendly experience in which the use of legs is eliminated but the player does a very natural and physical movement through virtual space. Apart from the head, the avatar only consists of two limbs, which represent the arms and hands of the player. He is able to walk, climb, jump, and glide with them. Imagine your body consisting only of hands, arms, chest and head. With the use of inverse kinematics (IK) it is possible to transfer the movement of the real arm to the virtual arm when using hand motion controllers.
In early development we used the Oculus Rift DK1 and Razer Hydra, which at the time delivered precise data. At that time there was no expectation at all that something like the setup we used would be anywhere near to release for consumers. So we focused on pushing immersion as far as possible and worked on a full body installation with a kind of hammock that keeps you standing or kneeling in a 30 degree forward angle.
We were also working on a quadrocopter based wind feedback that is directly linked to the avatars moving speed and direction to give more realistic feedback and feeling of movement and acceleration.
Since the summer of 2014, we switched from the wired Razer Hydra to the wireless PlayStation Move controllers in combination with the Rift DK2 and collected feedback while demoing at art and game events. Since the summer of 2015 we have been working with the HTC Vive devkits - we couldn’t believe our luck when Valve and HTC announced that they were producing exactly they setup we we needed for consumers.
From that time on we decided to completely focus on building a version of Lucid Trips that is suitable for public release.
Adjustments through Playtesting
As we opened up play testing to a constantly growing number of enthusiast and VR newbies we learned that we had to implement a lot more comfort mechanics than we thought. As in the beginning our avatar had a realistic gravity and the user could just start to walk and run forward, jump off the ground, spread their arms and fly. Players were even able to do loops. One can guess that even if we ourselves were feeling totally fine with this some playtesters weren’t at all.
We implemented some specific features that minimise the potential of nausea drastically. We altered the environment to have a very low gravity that makes large and frequent up and down movements not possible until wanted. These movements challenged the vestibular sense a lot and therefore easily lead to sickness. To stabilise the gaze we added localised particles in the player’s view and a vignetting that reacts to certain, especially unwanted, moves in backwards or sidewards directions - both can be adjusted through the comfort level on the touchpad from one to seven.
After 3 years of prototyping and iteration the user is now able to seamlessly switch from walking to jumping, flying or climbing, which lets him explore the magic environments on the artistically designed dreamplanet in Lucid Trips moving around completely free. It opens up a whole other possibility of perception of the virtual worlds in terms of space and dimensions.
Our current Early Access release is on Steam. We are also playtesting and developing with the Rift and Touch controllers and are targeting a release on Oculus as soon as we reach the full release state. A version for Playstation VR is also planned but as we are a small team all additional platform releases depend on how the game will perform through Early Access and the response of the community.