OpenTTD-JRPM Project Introduction

What is it

OpenTTD-JRPM (jrpm) is a secondary development branch based on JGR's Patchpack (jgrpp), incorporating the "train decoupling" and "modular airport" features from pulsexlb/OpenTTD-patches, along with jrpm-specific functionality. Current version jrpm-0.1.0.

It is a fully standalone installable, standalone multiplayer version: jrpm clients/servers use an independent version identifier (jrpm-0.1.0) for handshake, fully isolated from original jgrpp and pulsexlb versions to avoid version confusion.

Feature Overview

From pulsexlb (152 commits, merged via git merge)

• Train Decoupling (decouple): Complete train decouple/couple system -- decouple orders, path signal transfer, coupling length and speed limits, dual-head support, NewGRF coupling, coupling pathfinding (YAPF/NPF), and independent scheduling after decoupling;
• Modular Airports (multitile-airport): Multitile airport system overhaul -- air type system (air.h/air_type.h/newgrf_airtype.*), PBS air traffic control (pbs_air.*), YAPF air pathfinding, station.allow_modify_airports for airport layout modification, gui.default_air_type for default air type.

jrpm Exclusive

Feature	Description	Entry Point
Resource Download: Multi-Mirror + Parallel	Comma-separated multi-mirror sources, file-level parallel download (configurable concurrency), automatic mirror fallback on failure	Settings → network.content_mirrors / network.content_download_parallel
Vehicle Auto-Grouping	One-click auto-create and assign groups by shared orders/schedules, group names automatically derived from route names	Group window button / Console autogroup
Build Cost Tooltip	Real-time estimated cost displayed at mouse cursor when building rails/roads/terrain	Rail/road/terrain toolbar
Whole-Game-Aware AI	Retains NoAI, adds new AIGlobal global API + example AI GlobalAI, access controlled by game setting	game.script.allow_global_ai_access
Server Multi-Version Compatibility	jrpm server accepts jrpm / original jgrpp / pulsexlb clients simultaneously	Server-side check activates automatically

Complete Inheritance

• All jgrpp features (signal enhancements, scheduled dispatch, tracerestrict, template replacement, etc.);
• All upstream OpenTTD functionality and NewGRF/script ecosystem compatibility.

Version Relationship

                 jgrpp-0.73.1 (common ancestor)
                 /                 \
 jgrpp branch (63 commits)        pulsexlb px-patch (152 commits)
 ├ jgrpp recent updates            ├ train decoupling (decouple branch)
 ├ jrpm exclusive features         └ modular airports (multitile-airport branch)
 └ version renamed jrpm-0.1.0
                 \                 /
                  jrpm branch (git merge)

Branches and Commits

• Branch: jrpm (development mainline)
• Key commits:
  • d4c45740 jrpm exclusive 5 features
  • 71fe214c merge pulsexlb (decoupling + modular airports)
  • 425e7207 version renamed openttd-jrpm / jrpm-0.1.0
  • cb9848b7 server multi-version client compatibility
  • 4716b925 parallel download concurrency configurable

License

Same as OpenTTD: GPL-2.0.