External Ballistics Simulator 2D: Drag & Crosswind

This 2D companion strips the 3D artillery range down to a clean side-on view so the physics is legible at a glance: the same semi-implicit drag-coupled integrator as the 3D scene runs behind a flat range chart, but now a dashed drag-free parabola is drawn for the identical muzzle velocity and angle, so the gap between it and the solid drag trail directly shows how much energy air resistance bleeds off. An air-density slider lets you thin the atmosphere toward high-altitude conditions and watch that gap shrink, live speed and drag-deceleration readouts update every frame during flight (not just at impact), and a wind arrow indicator shows crosswind direction and rough magnitude at a glance.