Source map

Where the behavior these docs describe lives in skild-ai/newton. Paths are relative to newton/_src/solvers/steel/.

Topic	Source
Options, supported features, limitations	solver_steel.py: SolverSteel class and __init__ docstrings
Step-time options	solver_steel.py: _StepOption, _FrictionGapOption
steel: attributes	solver_steel.py: SolverSteel.register_custom_attributes
Unsupported model features	solver_steel.py: _validate_supported_model; gradients in SolverSteel.__init__
Coupled friction disk solve	friction.py: module docstring and coupled_contact_cuda (Newton steps, bisection fallback, KKT check)
Friction patches and anchors	friction_patches.py: module docstring, normal agreement 0.995, _SLIP_SATURATION_TOLERANCE
Contact row counts	kernels.py: contact_base_rows, free_rigid_angular_slots
Kinematic DOF armature	kernels.py: compute_effective_joint_armature
Gyroscopic microsteps	kernels.py: Cayley update of single-body free articulations
Small-world solve assignment	solver_steel.py: classify_local_solve_worlds launch
One-launch colored solve	latency_fused.py; solver_steel.py: latency-mode setup
Island sleeping	sleeping.py: island union-find and wake events
Contact compliance, torsion, adhesion	contact_compliance.py, contact_torsion.py, contact_torsion_device.py, contact_adhesion.py
Row watermarks and status	solver_steel.py: constraint_row_watermarks, check_constraint_capacity, snapshot_constraint_status
Observables	solver_steel.py: class docstring “Solver observables”; Newton docs/concepts/solver_observables.rst
Coupling	solver_steel.py: coupling_* methods; Newton docs/concepts/coupling.rst
Determinism	__init__ docstring of deterministic; Newton docs/concepts/determinism.rst

Steel is part of Newton and licensed under Apache-2.0. The third-party code and fonts this site ships are listed with their licenses in third-party notices. Throughput benchmarks for Steel are in the launch post; the frame-time changes quoted in the warm-start FAQ come from site/scripts/experiments/warmstart_experiment.py. The reference pages are generated by site/scripts/gen_reference.py.