Closeup of a scared person in a dark cave holding a torch

Improved Dynamic Line-of-Sight

The easiest way to handle vision in TTRPGs

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In the newest Fey-Gate update, we greatly improved dynamic Line-of-Sight. This highly anticipated update promises to transform gameplay, offering an automated solution to one of tabletop role-playing's most complex tasks—lighting and visibility.

What is Line-of-Sight?

The Line-of-Sight feature dynamically adjusts a character's vision as they move through the game's virtual environment. In a nutshell, this means that Dungeon Masters no longer have to manually reveal areas on the map. The feature automates this task, calculating vision and light in real-time based on each character's position.

How to Use It

To access this feature, click on the moon icon beneath the campfire symbol within the app. This activates a "dark mode," overlaying the entire map with a layer of darkness. Dungeon Masters can still see everything—albeit a bit darker—while for players, areas outside their line of sight remain completely hidden.

One noteworthy aspect is the ability to set individual and group lighting. Characters can be assigned their own "vision range" for dark vision and a "light range" for torchlight or magical illumination. What's more, using the "light range" affects the visibility of everyone in the group, not just the individual holding it.



Developing the feature was no small feat. Implemented through plain JavaScript and intensive mathematical algorithms, the feature casts multiple rays to different points in the environment. These rays determine potential paths for light travel, revealing or concealing areas as characters move.

Performance optimization was one of the more significant challenges, eventually solved through a multi-threaded approach and various improvements to reduce unnecessary calculations.

Conclusion and Future Plans

The updated Line-of-Sight feature is a milestone in Fey-Gate's ability to enhance the digital D&D experience, removing a labor-intensive task from the Dungeon Master's plate and making gameplay more immersive and strategic. The feature is now available in the latest version of Fey-Gate, offering a smoother and more interactive role-playing experience for all.

While we currently have no plans for further updates to this feature, we may be adding aesthetic enhancements, such as changing the color tint of different light sources in the future. If you have any suggestions on improvements, feel free to join our Discord and let us know!