From Sand to Simulation: Building a Cozy Sandbox Game

Fabien Weibel began his career in 3D animation and later worked as an art director on animated series, including a project for Rovio. In 2019 he started his first game, Haven Park, and founded his own studio in 2021. After releasing Trackline Express, he turned his attention to a new title, Sandcastle.

The idea for Sandcastle emerged after a period of re‑scoping a larger, more complex project. Weibel decided to keep only the parts he enjoyed: the water and sand simulation. He realized that a game centered on building sand castles would be a unique niche.

Using Unity, he built the entire water and sand simulation from scratch, without relying on third‑party plugins. He consulted scientific papers on fluid dynamics to model the water and adapted those principles for sand, treating it as a highly viscous fluid.

A major technical hurdle was running the water and sand simulations at different resolutions. The coupling produced artifacts in the sand, which he mitigated by adding random noise to smooth the results and give the beach a natural texture.

Weibel also implemented controls for erosion and sedimentation, a feature that players have requested. Continuous player feedback is used to refine these mechanics.

For designers and animators, the project demonstrates how custom physics can create engaging gameplay experiences. It shows that investing time in building your own tools can pay off in terms of creative freedom.

Looking ahead, the team plans to add more building tools and personalization options. They are also preparing a full release for multiple platforms, so keep an eye on upcoming updates.