A real-time ballistic solver for moving targets under drag (C++)
Details
- External ID
- 46566390
- Source
- HN
- Company
- —
- Product
- —
- Website domain
- —
- Launched
- Jan. 10, 2026
- Cohort
- —
- Upvotes
- 5
- Upvotes percentile
- 0.09617918313570488
- Tags
- —
- Fetched at
- Sept. 7, 2026, 9:25 p.m.
- Updated at
- Sept. 7, 2026, 9:25 p.m.
Description
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 constraintsThe 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-solverI’d be very interested in feedback, criticism, or discussion around the numerical approach, performance trade-offs, or edge cases I might have missed.
Enrichment
- Theme
- 3D graphics and physics simulation tools
- Vertical
- Horizontal
- Function
- Dev tools
- Audience
- Developer
- AI stance
- Not AI
- Project type
- Hobby / open-source project
- Normalized one-liner
- ballistic physics calculation library
- Manually corrected
- False
Could you build this?
No Developing a real-time ballistic solver with air drag against moving targets requires advanced applied mathematics and numerical methods for differential equations.
What it would actually take: This requires solving a system of non-linear ordinary differential equations (ODEs) incorporating aerodynamic drag models (such as G1/G7 drag functions) coupled with root-finding algorithms (e.g., Runge-Kutta numerical integration combined with Newton-Raphson or Brent's method) to solve two-point boundary intercept problems in real-time. Specialized expertise in numerical analysis, physics simulation, and high-performance C++ optimization is required.
Discussion
2 comments analyzed.
Competitors
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Attention rank: #39 of 47 (itself plus its competitors, highest first — normalized so YC and Product Hunt are compared fairly).
Launched 59 days after the earliest competitor.
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Other launches for this product
- No other launches for this product.
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