v0.4.0

0.4.0 (2026-10-25)

Changed

• Breaking: the API and replay refuse magnitudes past fixed limits.
  Every value a call or a recorded op takes is bounded, so every product
  the step forms from them stays finite. A call past a limit refuses
  with m3_errorInvalid (a create returns the null id), counts one
  misuse, journals nothing and changes nothing, and replay refuses the
  same values through the same checks. Among the limits: speeds within
  1e5 m/s and rad/s per component (a kinematic body's linear speed
  within 1e10 m/s), gravity within 1e4 m/s^2, frequencies within 1e5 Hz,
  dimensionless ratios within 1e4, step lengths from 1e-4 to 10 s,
  forces and torques within 1e20, and on a dynamic body every
  mass-bearing shape at least 1e-6 kg with every principal moment at
  least 1e-12 kg m^2 and the body at most 1e20 kg. The guide's
  "Magnitude limits" chapter and the header docs list every limit per
  call. A body holding static-only scenery cannot leave static, and a
  teleport or a type change cancels a pending servo target
  (#81).
• Breaking: m3Shape_SetDensity always rebuilds the body's mass. It
  takes no updateBodyMass argument, and its journal record shrinks
  from 16 to 12 bytes. A body's mass, center and inertia are now always
  derived from its type and shapes
  (#82).
• Breaking: the snapshot format is 3. Mass, center, inertia and
  extents are rebuilt on restore rather than stored, bit for bit as the
  source world had them, and a format 2 snapshot is refused
  (#82).
• On 32-bit x86 the library is built with SSE2 math
  (-msse2 -mfpmath=sse), so it needs a processor with SSE2, and every
  build now leaves trapping math at the compiler's default, from the
  family's compiler flags. On AVX2 the solver's min and max are one
  instruction each, with the same bits. Every golden scene and bench
  hash is unchanged on x64 and i686, with GCC and Clang
  (#85).

Fixed

• Restore accepts only what a world built through the API could hold.
  It refuses any value past the limit its create or setter keeps, a
  position past 1e18 m, a dynamic body whose shapes break the mass
  floors or limit, and a contact manifold with a float that is not
  finite. The step holds every body and soft particle within 1e18 m and
  a loaded warm start within a limit. Every ordinary impulse keeps its
  bits, and every golden scene's result is unchanged; only the snapshot
  and journal byte hashes moved with the formats
  (#82).
• The step keeps every dynamic body, particle and joint row within
  1e5 m/s and rad/s after the warm start, restitution and the soft-body
  pass, and caps a joint row's correction speed there, so an error of
  any size closes no faster than a body may move. A body's inverse
  inertia is exact at any scale
  (#76).
• The gyroscopic step and the solver's small inverses (the contact
  tangent pair, the joint row pair and the 3x3 solve) solve at unit
  scale when the direct result is not finite or the determinant is not
  a normal float, instead of dropping the term or giving zero. Every
  ordinary system goes through the same operations and gives the same
  bits, and every golden and bench hash is unchanged
  (#79,
  #80).
• Replay applies each op's public checks: the sleep controls, waking a
  body, a hull's points, tank commands, joint targets and voxel edits
  are refused on replay exactly where their calls refuse them, and the
  journal reader checks each record's length as the replay reader does.
  A soft lattice def is refused, by the call and on replay, when any one
  of its counts passes the particle cap
  (#86).