YonderCore

YonderCore is a high-performance Rust-based library designed for processing transit data, specifically optimized for integration into iOS and macOS applications. It provides a robust backend for handling GTFS (General Transit Feed Specification) data, including static lookups, real-time updates, and smooth vehicle position interpolation.

Features

• GTFS Static Lookup: Efficiently parses static GTFS files (routes, trips, stops, etc.) using HTTP range requests to minimize data transfer.
• Shape Interpolation: Computes smooth, interpolated vehicle positions between GPS pings based on shapes.txt and stop_times.txt.
• Real-time Enrichment: Integrates GTFS-RT (Real-time) feeds to provide live vehicle positions, trip updates, and occupancy status.
• Spatial Indexing: Uses an R-tree for fast O(log n) spatial queries to find nearby stops.
• Zero-Copy Tile Caching: Implements a high-performance tile cache using rkyv for zero-copy deserialization.
• Thread-Safe Architecture: Designed with thread-safe data structures (Arc, RwLock, Mutex) to handle concurrent access in mobile environments.

Project Structure

• lib.rs The main entry point and FFI (Foreign Function Interface) layer.
• gtfs_static.rs Handles parsing and lookup of static GTFS data and shape interpolation logic.
• gtfs_rt.rs Manages GTFS-RT Protobuf message definitions and feed parsing.
• tile_cache.rs A disk and memory-based caching system for map tiles and metadata.