A real-time ballistic solver for moving targets under drag (C++)
Hi HN, I’m sharing a small open-source project I’ve been working on: a native C++ ballistic solver that computes launch angles to intercept moving targets in real time, under gravity and air drag. Instead of relying on vacuum assumptions, closed-form equations, or lookup tables, the solver formulates the intercept as a nonlinear problem and solves it numerically using time integration and iterative methods. The motivation came from game and simulation scenarios where simpler approaches tend to break down: - moving targets - strongly curved trajectories due to drag - real-time constraints The…
What it does
In the maker’s words, at launch
Hi HN, I’m sharing a small open-source project I’ve been working on: a native C++ ballistic solver that computes launch angles to intercept moving targets in real time, under gravity and air drag. Instead of relying on vacuum assumptions, closed-form equations, or lookup tables, the solver formulates the intercept as a nonlinear problem and solves it numerically using time integration and iterative methods. The motivation came from game and simulation scenarios where simpler approaches tend to break down: - moving targets - strongly curved trajectories due to drag - real-time constraints The solver simulates projectile motion (RK-style integration), tracks the closest approach to the target, and iteratively adjusts the launch direction until an intercept is achieved. It’s written in C++ and exposed through a stable C ABI, so it can be used from environments like Python or game engines (e.g. Unity) without rewriting the core logic. Project page: https://github.com/ujinf74/ballistic-solver I’d be very interested in feedback, criticism, or discussion around the numerical approach, performance trade-offs, or edge cases I might have missed.
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