The Tomb Raider series let the player solve puzzles, explore and fighting enemies. Tobii was given the opportunity to add eye tracking to Shadow of the Tomb Raider in 2018. The game was far in development at that time so Tobii mainly focused on changing the game mechanics to enhance the experience of playing with eye tracking.

We decided to focus on creating meaningful eye tracking features, which directed us concentrating on few features and making them shine.

As eye tracking is a technology that changes conditions on how the player interact with game we focused on how to change game mechanics in the game. During the development process we understood that we need to cater for the identity of Lara as well as how the Tomb Raider series is usually played by the audience.

We mainly redesigned a set of game mechanics with the basic activities in mind; exploration, puzzle solving and combat. We also acknowledged how other aspects of the game, such as the franchise, reinforced attributes of our redesigned mechanics. Our feature set turned out to be:

• Aim & Throw at Gaze, meaning you would aim at the position to where you look.
• Awareness, in which we redesign the Survival Instinct feature to become controlled by gaze.
• Extended View, to support rotation of the main camera through gaze.

Aim at Gaze would automatically snap to enemies by simply looking at them. We justified our proposed interaction by connecting the feature to Lara Crofts awesome shooting skills and the fact that Shadow of Tomb Raider is not a shooter game. Recognizing Lara’s powerful skills and invite the user to experience the sensation of empowerment was reasonable.

A learning from this approach is also to acknowledge how the game is usually played, which declares that Lara usually employ stealth attacks and uses headshots with bow to swiftly eliminate enemies. In this sense we needed to involve other aspects of the game to drive the design of the aiming mechanics. The end result was a combination of aiming with your eyes and being able to make headshots.

The other focus was exploration. We supported this activity by reinforcing the activity with eye tracking. With eye tracking we made it possible to combine a feature in the game, Survival Instinct, to be used in a fluent manner in the game. With eye tracking the user no longer must press the Survival Instinct button to perceive objects of interest. The user can instead move Lara around and identify these objects in a fluent manner. We named the feature Survival Instinct Awareness, the feature not only empowered the user to immediately recognize objects of interest but also improved quality of life as we could combine several interaction techniques into one gameplay experience.

”It is basically a quality of life feature. Normally I keep turning Survival Instincts on and off, but this makes it all a better immersive gameplay”

– John, play tester 4

Features Description

Aim at Gaze

When users press aim key, Lara animates to an aim position without zooming in and target the enemy the user looks at. By using a clever component, we can identify what enemy the user is most likely interested in targeting. Not only do this feature add to sensation of empowerment but also decreases disorientation the user might feel as the camera is zoomed to target.

For gamepad users, the feature will also have a compensating effect to overcome accuracy difficulties when aiming at targets with a controller.

Throw at Gaze

Throwing in Shadow of the Tomb Raider is improved with eye tracking. As the user press the throw button an arc appears with end position at the spot where the user looks at. This adds both to the sensation of empowerment and quality of life as user’s intent and interest drives the throwing mechanism.

Extended View

Extended view is a feature to automatically rotate the camera according to user’s intent to get a wider view of the surrounding, which facilitate a sensation of presence.

Trap Awareness

A special awareness feature was created for the Shadow game when playing with a gamepad. When moving Lara close to a trap and looking at a trap the gamepad rumbles to provide tactile feedback and warn the player.

Character Awareness

In certain situations when player looks at characters they turn their head towards Lara to signal awareness.