Module transform 

Pipeline-mechanical clip transforms, ported from the incubating bake’s Python: frame-window slicing, hold-extension, duplicate-endpoint removal, and gait-anchor rotation. Scope rule (DESIGN.md §1): animsmith may rewrite a clip only in ways whose correctness its own checks can verify.

Structs

ConstantTrackPruneRecord

One constant-track candidate considered by prune_constant_tracks.

ConstantTrackRetainedRecord

A candidate that prune_constant_tracks conservatively retained.

DuplicateLoopEndpointOutcome

The lossless change made by drop_duplicate_loop_endpoint.

GaitAlignOutcome

Outcome of align_gait_anchor.

PruneConstantTracksOutcome

Outcome of prune_constant_tracks.

Enums

ConstantTrackRetentionReason

Reason a constant-track candidate was not removed.

DuplicateLoopEndpointError

Failure while analyzing a duplicate loop endpoint.

GaitTrajectoryPolicy

Declared movement contract under which gait-anchor rotation may run.

Constants

CONSTANT_TRACK_PRUNE_QUAT_TOLERANCE_RAD

Maximum sign-invariant local rotation change accepted when pruning a constant track. This aliases the constant-track check’s tolerance.

CONSTANT_TRACK_PRUNE_VEC3_TOLERANCE

Maximum component-wise local translation/scale change accepted when pruning a constant track. This aliases the constant-track check’s classification tolerance.

DUPLICATE_ENDPOINT_QUATERNION_TOLERANCE_RAD

Sign-invariant shortest-path angular tolerance for duplicate rotations.

DUPLICATE_ENDPOINT_VEC3_TOLERANCE

Component-wise tolerance for duplicate translation and scale endpoints.

GAIT_ANCHOR_MAX_HORIZONTAL_ACCUMULATION_M

Maximum horizontal root-trajectory endpoint displacement admitted by the in-place gait-anchor policy.

GAIT_ANCHOR_MAX_TRAJECTORY_POSE_SAMPLES

Maximum samples admitted by each in-place gait work bound.

GAIT_ANCHOR_MAX_YAW_ACCUMULATION_DEG

Maximum accumulated root yaw admitted by the in-place gait-anchor policy.

Functions

align_gait_anchor

Rotate a cyclic clip in time so its measured stride anchor (the trough of the L−R foot-height fundamental) lands at clip time 0.

analyze_duplicate_loop_endpoint

Analyze whether a clip has a safe, duplicated loop endpoint.

drop_duplicate_loop_endpoint

Atomically remove all consecutive duplicate closing keys from every track.

hold_extend

Append one key per track duplicating its final value hold_s seconds after its last key (a linear hold — charge/block poses). The clip duration extends to the longest held end.

prune_constant_tracks

Remove constant multi-key tracks only when doing so preserves every local TRS and model-space position/rotation on the original clip’s default sample grid.

slice

Keep only the keys inside [start, end] seconds (with a half-frame epsilon at fps absorbing float drift from earlier retimings) and retime them so the window starts at 0. Cubic tangent triplets move with their keys. The clip duration becomes end - start.