Project Structure

AeroLiners Set is a CMake-driven NewGRF project. The source is written in NML and organized into thousands of source files via the C preprocessor (#include and #define in .pnml files). The following breaks down the whole repository by directory.

AeroLinersSet/
├── CMakeLists.txt          # Top-level build definitions (NML / GRF / Bundles targets)
├── CMakePresets.json       # CMake presets (Ninja / Make / VS generators)
├── Makefile                # CMake-generated build entry (make / make clean)
├── WAS.pnml                # Main entry: #include all aircraft source files
├── custom_tags.txt         # Build-time generated version / identity info
├── bin/                    # Build output: generated .grf and .nml
├── build/                  # CMake intermediate directory
├── docs/                   # This VitePress documentation (incl. readme.txt / license.txt / changelog.txt)
├── documentation/          # Misc docs, xlsx tracking sheets, logo, etc.
├── greyscales/             # Greyscale (base) livery PNGs per model, grouped by manufacturer
├── lang/                   # 15 language files (*.lng)
├── scripts/                # 3 CMake scripts driving NML/GRF/doc processing
├── sprites/                # Historical / auxiliary sprite assets (pcx / nfo / png / examplenfo)
└── src/                    # Core source
    ├── *.pnml              # Top-level definitions (header / check / basecost / cargotable ...)
    ├── gfx/                # All aircraft, in manufacturer / series / model three-level dirs
    └── sound/              # Takeoff & landing sounds (.wav)

Core source (src/)

File	Role
header.pnml	GRF header: grfid (AERO), name, url, version, and the 4 adjustable parameters
check.pnml	Compiler / environment check macros
basecost.pnml	Base cost related definitions
cargotable.pnml	Cargo table definition, corresponding to refit options
definition.pnml	Common macros: get_model_life, get_retire_early, plane_speed_kmh, plane_RC, flight_state, etc.
graph_templates.pnml	Graphics templates (spriteset template macros)
disable_origin.pnml	Switches to disable original aircraft, etc.
sort_order.pnml	Sort order definitions for the purchase list
gfx/	One directory per model, containing a .pnml (aircraft logic) and several .png (livery sprites)
sound/	Takeoff & landing sound files (av_turbogo.wav, av_landturbo.wav)

Aircraft source files (src/gfx/)

• Three-level directory structure: manufacturer / series / specific model. For example Boeing / B737 / B737-800 /.
• Each model directory contains:
  • One model.pnml: defines the aircraft's spriteset, state switches, properties, and graphics.
  • Several .png livery files: each PNG corresponds to one airline livery (including a (0)Greyscale.png as the greyscale base).
• Currently about 157 model .pnml files and about 1743 livery PNGs.

src/gfx/Boeing/B737/B737-800/
├── (0)Greyscale.png      # Greyscale base livery
├── B737-800.pnml         # Aircraft logic + sprite references
├── AerLingus.png         # Airline liveries
├── Lufthansa.png
└── ...

Language files (lang/)

• 15 .lng files, covering catalan, chinese_simplified, chinese_traditional, croatian, czech, dutch, english, finnish, german, indonesian, italian, korean, polish, russian, spanish.
• Declared via ##grflangid, providing localization for all STR_* strings (GRF name, parameter descriptions, model names, livery names, etc.).

Build scripts (scripts/)

Script	Role
Compile.cmake	Calls nmlc to compile .nml into the final .grf
GenerateCustomTags.cmake	Generates custom_tags.txt (version, GRF filename, date, etc.)
ProcessDocs.cmake	Calls grfid to compute MD5 and configure the three text files into the release bundle

Resource directory notes

• greyscales/: PNG backups/sources of each model's greyscale livery, grouped by manufacturer (129 .png).
• sprites/: historical and auxiliary assets, including pcx/, png/, nfo/, examplenfo/. nfo/ keeps the old NFO flow's string/sprite definitions; examplenfo/ holds callback examples (callback36.txt, xx.nfo).
• documentation/: development tracking sheets (xlsx), logo sources, old English lng, and other references.

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