v0.14.0

0.14.0 (2026-10-30)

This release finishes the API review for 1.0. The readers take the context const and read it when host code calls back in (#170). The calls on a clip's player are named for it (#178) and the two counters that were not are named Get...Count (#176). The reduced motion switch returns nothing (#174), the host easing's callback is a function type (#172), and mtwnMakeTrack takes the keyframes it rewrites first (#184). Three getters no longer crash on a null context, and a refused rough easing leaves its points. The getting started guide says what 1.0 will keep. No value, velocity or event record changes.

Changed

• Breaking: ten readers take a const mtwnContext* (#170): mtwnClip_GetTrack, mtwnClip_GetNode, mtwnClip_FindLabel, mtwnClip_GetDuration, mtwnTarget_GetValue, mtwnTarget_GetState, mtwnPlayer_GetState (now mtwnClipPlayer_GetState), mtwnContext_ReadTargets, mtwnContext_GetClipBytes and mtwnContext_MeasureTransition. C callers compile as before; a C++ pointer to one of them has a new type.

  • Called back in from the host's code the context runs (a host easing, the allocator, the task system's functions), all but mtwnTarget_GetState now read the context as the call in progress has left it, where they returned mtwn_errorBusy, and count no misuse.
  • mtwnTarget_GetState is still refused when called back in: a target's velocity may be computed when read, by sampling a host easing, which could otherwise call it again without end.
  • While an update's clip players run in groups on the host's task system, mtwnTarget_GetValue, mtwnContext_ReadTargets, mtwnClipPlayer_GetState and mtwnContext_MeasureTransition called from the host's code are refused with mtwn_errorBusy, one misuse counted, their outputs left as they were, since a group may be writing what they read.
  • mtwnDestroyClip and mtwnDestroyContext release a clip's id before the host's free gets its block, so a free that reads back the clip finds the id stale.

• Breaking: the calls that take only a clip's player are named for it (#178):

  Before	Now
  mtwnPlayer_Play, _Pause, _Reverse, _Finish, _Cancel	mtwnClipPlayer_Play, _Pause, _Reverse, _Finish, _Cancel
  mtwnPlayer_Seek, _Sweep, _SeekProgress, _SeekLabel	mtwnClipPlayer_Seek, _Sweep, _SeekProgress, _SeekLabel
  mtwnPlayer_SetRate, _SetWeight, _GetState	mtwnClipPlayer_SetRate, _SetWeight, _GetState
  mtwnCreatePlayer	mtwnCreateClipPlayer
  mtwnPlayerDef	mtwnClipPlayerDef
  mtwnDefaultPlayerDef	mtwnDefaultClipPlayerDef
  MTWN_PLAYER_DEF_COOKIE	MTWN_CLIP_PLAYER_DEF_COOKIE
  mtwnPlayerState	mtwnClipPlayerState

  mtwnPlayerId, mtwnDestroyPlayer and mtwnPlayer_IsValid, which take a transition's player too, and mtwnPlayState keep their names. Parameters, values and the cookie's value are unchanged.

• Breaking: mtwnContext_GetDroppedEvents is mtwnContext_GetDroppedEventCount and mtwnContext_GetSerialAdvances is mtwnContext_GetSerialAdvanceCount, as the family names its counters. Their parameters and behavior are unchanged (#176).

• Breaking: mtwnContext_EnableReducedMotion returns void. A null context changes nothing, and a call back in changes nothing and counts one misuse, as their refusals did; read the state with mtwnContext_IsReducedMotionEnabled (#174).

• Breaking: mtwnEaseFunction is a function type, double (void* context, double progress), as the task hooks' are: mtwnMakeHostEasing takes, and mtwnEasing.function holds, a mtwnEaseFunction*. Passing a function's name compiles as before; a variable of the old type is declared mtwnEaseFunction* (#172).

• Breaking: mtwnMakeTrack takes the keyframes and their count first and the def third: mtwnMakeTrack(keyframes, count, def, lengthsOut, mixesOut, trackOut). It rewrites the keyframes in place for angles and for rotations on the shortest path, so they are the call's object, as the family's conventions order it. A call in the old order no longer compiles (#184).

• docs/user/getting-started.md has a Compatibility section, linked from the README: what 1.0.0 will keep across 1.y (every function, type, enum value, macro and struct field in the headers, things only added), what it leaves out (the fields of the made value structs a host never reads), the binary interface within a minor version, and results the same bits on every platform, any change of a bit stated here. The transitions guide says to ask mtwnPlayer_IsValid before stopping a transition that may have ended (#180).

Fixed

• mtwnContext_GetMisuse, mtwnContext_GetSerialAdvanceCount and mtwnContext_GetMemoryBytes read 0 from a null context, where they crashed, as the other getters do (#165).
• A refused mtwnMakeRoughEasing leaves the caller's points as they were. A host shape giving a value that is not finite past the first inner points left part of a new set there; the shape is now sampled at every inner point before one is written (#168).
• mtwnFitLinearEasing says what a refused fit leaves in its points, which its header called unspecified: the fit's first points, at most the capacity, exactly as a larger buffer would start, and the rest as they were (#182).