@pathblender/core

Pure-function core of PathBlender: parse FRC autonomous path files into a unified trajectory model, then fuse, replay, and collision- check them. Zero DOM, zero dependencies, fully synchronous — runs in any JS runtime (browser, Node, workers).

Used by the PathBlender web app and consumable as a library (e.g. by the sibling show-control project GHPaths for guest-path import).

Install

npm install @pathblender/core

What it does

| Area | Entry points | |---|---| | Parse any supported file | parsePathFile(text, fileName, resolvePath?) — auto-detects format; returns a Trajectory or throws ParseError with an actionable reason | | Supported formats | Choreo .traj (all known schema versions) · Collaborative fork .ghostauto · PathPlanner .path / .auto (trajectory generation ported from PathPlannerLib) · PathBlender .pb session files (pre-rename .ghpb.json still reads) | | Unified model | Trajectory / TrajectorySample in WPILib blue-origin meters/radians; applyAllianceChange normalizes red-alliance exports | | Fusion & playback | SessionTrajectory, samplePoseAt, sessionDuration, serializeSession / deserializeSession | | Collision checking | detectCollisions (bumper OBB-SAT, 0.02 s sampling), minimumSeparation, detectFieldBounds | | Fields | FIELDS (2018–2020, 2022–2026 — no 2021: that season reused the 2020 field), makeCustomField, AprilTag layout parsing (WPILib/PhotonVision JSON) |

Everything is pure: same input, same output, no hidden state.

Attribution

Trajectory generation for .path/.auto is a TypeScript port of PathPlannerLib (MIT, mjansen4857/pathplanner). Red/blue alliance transform semantics follow WPILib conventions. See the repository NOTICE.md for the full attribution list.