Optionalgravityinitial world gravity, default {x: 0, y: 1} (matter-js convention)
Optionalmatterraw matter-js engine options forwarded to Matter.Engine.create().
Use this to tweak solver iterations, constraint accuracy, etc.
OptionalsubNumber of physics substeps per engine frame. Each call to
MatterAdapter.step runs Engine.update(engine, dt / N)
N times instead of one full-dt step. Increases narrow-phase
accuracy at high relative velocities (break shots, projectiles)
at the cost of ~N× physics CPU. Default 1 matches the legacy
single-step behaviour. Values < 1 are clamped to 1.
Options accepted by the MatterAdapter constructor.