Actinium

Sci-Fi Top-down shooter

Actinium is a Top-down shooter inspired by games like Hotline Miami and OTXO, but with a sci-fi theme.

Something I liked about those games is the persistent carnage that remained in the map as you go. Walking back through levels once completed is really interesting to see a record of your actions.

Prototyping

One thing that went really well on this project was committing to a fast, scrappy prototype before worrying about polish. I built the prototype in about a week, which let me gather feedback almost immediately.

Visual Style

Early on, I wasn’t sure whether the game should be 2D or 3D. Both had legitimate advantages, so I implemented a toggle and built both versions side by side. This turned out to be incredibly helpful—I learned things I wouldn’t have noticed without seeing the options in action. In the end, I chose 3D because it felt more dynamic, represented depth more naturally, and created a more distinctive visual style.

From there, I iterated further on the 3D approach and focused on sharpening some of the core visual features.

Stencil Shader

I used a stencil shader to carve a hole in the outer hull of the ship, making the interior appear embedded within the larger structure. This added a strong sense of depth and made it feel like the player was truly inside the ship rather than floating above a flat layout.

Line of Sight

The line-of-sight system generated a mesh at runtime using the player’s position and nearby wall corners. That mesh drove another stencil shader that revealed characters and objects only within visible areas. I also added a screen-space effect that gave unseen regions a holographic, scan-line appearance, which helped sell the sci-fi aesthetic.

Conclusion

This project was a big success in terms of validating the concept quickly and gathering early feedback. Testers responded very positively.

The biggest takeaway for me was just how valuable rapid prototyping can be. Before this, I often got stuck polishing details too early, without confirming whether the core idea worked.

I’ve parked this project for now to focus on other things, but I’d love to come back to it in the future.