Newtonian gravity: sum of G·dm·r̂ / r² over a circular slab. No relativity.
Finite disk: radius — km; thickness varies by taper. Top surface only.
Density: base ρ with optional center bias. Mountains/oceans ignored.
Spin (optional): simple centrifugal term ω²r (ω=2π/Day).
Softening: tiny height ε above surface to avoid singularities; thickness integrated as an average depth.
Symmetry: radial profile + rotation → fast field.
Continents overlay: schematic, azimuthal‑ish outlines for teaching; not geodetic.
What it might feel like: near the center plumb lines are nearly straight; toward the edge ‘down’ leans inward—walking feels like a constant slight slope toward the middle. Weight changes with radius.