Baking Pipeline

This document explains the engine resource baking pipeline: where it is wired, which source files own baker behavior, and how to validate changes. For the broader engine tool map, see Tools.md.

Use this for reusable engine behavior. Game-specific content folder rules and product package policy belong in the embedding project’s docs.

Source paths inspected

• BuildTools/cmake/stages/ScriptsAndBaking.cmake
• BuildTools/cmake/helpers/WriteBuildHash.cmake
• Source/Applications/BakerApp.cpp
• Source/Applications/BakerLib.cpp
• Source/Tools/Baker.h
• Source/Tools/Baker.cpp
• Source/Tools/MetadataBaker.h
• Source/Tools/MetadataBaker.cpp
• Source/Tools/ConfigBaker.h
• Source/Tools/ConfigBaker.cpp
• Source/Tools/RawCopyBaker.h
• Source/Tools/RawCopyBaker.cpp
• Source/Tools/ImageBaker.h
• Source/Tools/ImageBaker.cpp
• Source/Tools/EffectBaker.h
• Source/Tools/EffectBaker.cpp
• Source/Tools/ProtoBaker.h
• Source/Tools/ProtoBaker.cpp
• Source/Tools/MapBaker.h
• Source/Tools/MapBaker.cpp
• Source/Tools/TextBaker.h
• Source/Tools/TextBaker.cpp
• Source/Tools/ProtoTextBaker.h
• Source/Tools/ProtoTextBaker.cpp
• Source/Tools/ModelMeshBaker.h
• Source/Tools/ModelMeshBaker.cpp
• Source/Tools/ModelInfoBaker.h
• Source/Tools/ModelInfoBaker.cpp
• Source/Tools/AngelScriptBaker.h
• Source/Tools/AngelScriptBaker.cpp
• Source/Tests/Test_BakerSetup.cpp
• Source/Tests/Test_MetadataBaker.cpp
• Source/Tests/Test_ConfigBaker.cpp
• Source/Tests/Test_RawCopyBaker.cpp
• Source/Tests/Test_ImageBaker.cpp
• Source/Tests/Test_EffectBaker.cpp
• Source/Tests/Test_ProtoBaker.cpp
• Source/Tests/Test_ProtoTextBaker.cpp
• Source/Tests/Test_MapBaker.cpp
• Source/Tests/Test_TextBaker.cpp
• Source/Tests/Test_ModelBaker.cpp
• Source/Tests/Test_AngelScriptBaker.cpp

What baking does

Baking turns project resources and configuration into runtime-ready output. The build pipeline creates BakeResources and ForceBakeResources command targets in BuildTools/cmake/stages/ScriptsAndBaking.cmake. Those targets run the project baker application with the embedding project’s main config applied.

At runtime/source level, baking is owned by:

• Source/Applications/BakerApp.cpp — executable app wrapper that constructs MasterBaker and calls BakeAll().
• Source/Applications/BakerLib.cpp — exported library entry point FO_BakeResources() for library-based baking flows.
• Source/Tools/Baker.h / Source/Tools/Baker.cpp — shared baking context, baker setup, data source, output writing, and MasterBaker.

CMake entry points

BuildTools/cmake/stages/ScriptsAndBaking.cmake creates baking commands after application targets are available.

Current target responsibilities:

• BakeResources runs the project baker with -ForceBaking False.
• ForceBakeResources runs the project baker with -ForceBaking True.
• Both apply the embedding project’s main config through -ApplyConfig <FO_MAIN_CONFIG> and -ApplySubConfig NONE.
• Both work from FO_OUTPUT_PATH.
• Resource build-hash state is written through BuildTools/cmake/helpers/WriteBuildHash.cmake using Baking/Resources.build-hash.

The actual final target names that depend on these commands are project/preset-dependent. Do not document one embedding project’s target names as universal engine behavior.

Runtime classes

BakingContext

Defined in Source/Tools/Baker.h. It carries shared bake state:

• Settings — BakingSettings for the current bake.
• PackName — current resource pack name.
• BakeChecker — callback used to decide whether existing baked data is still valid.
• WriteData — async output writer callback.
• BakedFiles — existing baked file data source.
• ForceSyncMode — optional override for synchronous execution.

BaseBaker

The abstract base for individual baker implementations. Each baker provides:

• GetName() — stable baker name used by setup/config selection.
• GetOrder() — ordering key for deterministic bake ordering.
• BakeFiles() — the actual file transformation step.

BaseBaker::SetupBakers() in Source/Tools/Baker.cpp creates requested bakers and then calls SetupBakersHook() so external/project code can extend the baker list.

MasterBaker

MasterBaker coordinates a full bake through BakeAll(). It is the app-facing type used by both BakerApp.cpp and BakerLib.cpp.

BakerDataSource

BakerDataSource adapts resource inputs/outputs to the engine DataSource interface. It tracks input resource packs, output resources, cache checks, and output path construction.

Built-in baker types

Source/Tools/Baker.cpp registers built-in bakers when requested and enabled:

• MetadataBaker — Source/Tools/MetadataBaker.*
• ConfigBaker — Source/Tools/ConfigBaker.*, name Config, order 2
• RawCopyBaker — Source/Tools/RawCopyBaker.*, name RawCopy, order 4
• ImageBaker — Source/Tools/ImageBaker.*
• EffectBaker — Source/Tools/EffectBaker.*
• ProtoBaker — Source/Tools/ProtoBaker.*, name Proto, order 6
• MapBaker — Source/Tools/MapBaker.*, name Map, order 7
• TextBaker — Source/Tools/TextBaker.*, name Text, order 4
• ProtoTextBaker — Source/Tools/ProtoTextBaker.*
• ModelMeshBaker — Source/Tools/ModelMeshBaker.*, enabled when FO_ENABLE_3D is active
• ModelInfoBaker — Source/Tools/ModelInfoBaker.*, enabled when FO_ENABLE_3D is active
• AngelScriptBaker — Source/Tools/AngelScriptBaker.*, enabled when FO_ANGELSCRIPT_SCRIPTING is active

When documenting a specific asset type, inspect the relevant baker class and its tests rather than inferring behavior from file extensions alone.

MapBaker writes separate server and client map blobs. The client blob serializes visible static items, and its hash dictionary is also accumulated from client-side properties of hidden static items so Common hstring values can resolve later without exposing the hidden item entities.

Script compilation relationship

ScriptsAndBaking.cmake also creates script compilation commands:

• CompileAngelScript runs the project AS compiler target when FO_ANGELSCRIPT_SCRIPTING is enabled.
• CompileMonoScripts runs BuildTools/compile-mono-scripts.py when FO_MONO_SCRIPTING is enabled.

These are separate command targets from resource baking, but they share the same stage because generated/baked runtime inputs are part of the same build preparation workflow.

Tests to inspect

Baker behavior is covered by focused tests in Source/Tests/:

• Test_BakerSetup.cpp
• Test_ConfigBaker.cpp
• Test_MetadataBaker.cpp
• Test_RawCopyBaker.cpp
• Test_ImageBaker.cpp
• Test_EffectBaker.cpp
• Test_ProtoBaker.cpp
• Test_ProtoTextBaker.cpp
• Test_MapBaker.cpp
• Test_TextBaker.cpp
• Test_ModelBaker.cpp
• Test_AngelScriptBaker.cpp

Use the smallest test that matches the baker you changed. If CMake target names are generated by the embedding project, discover them from that project’s presets/build files instead of hard-coding them here.

Change routing

• New baker type: add/modify Source/Tools/*Baker.*, register it in BaseBaker::SetupBakers() or through SetupBakersHook(), and add focused tests.
• Baking command arguments: update BuildTools/cmake/stages/ScriptsAndBaking.cmake.
• Resource build hash behavior: update BuildTools/cmake/helpers/WriteBuildHash.cmake and related tests/build validation.
• Metadata baking: update Source/Tools/MetadataBaker.* and GeneratedApiAndMetadata.md.
• Script-specific bake behavior: update Source/Tools/AngelScriptBaker.* and Scripting.md.

Validation checklist

1. Configure from an embedding project root.
2. Build the project baker application/library target if the changed path affects app/library code.
3. Run the relevant baker test(s) under Source/Tests/.
4. Run BakeResources for incremental behavior when cache/build-hash logic matters.
5. Run ForceBakeResources when forced rebuild behavior matters.
6. Inspect generated output only as output, not as hand-authored source.
7. Update this document and BuildToolsPipeline.md if stage responsibilities change.