# Shared C++ library plan

## Library contents

Move the deterministic CPU world pipeline into a portable `VoxelForgeCore` library: plain voxel
and world types, math/noise, density operations and caches, cave and passage fields, strate
composition, marching cubes, and desired clipmap tile selection. Keep renderer, file loading,
asset/reflection access, gameplay actors, and task scheduling in the host applications.

## Compatibility boundary

The library should expose standard C++ value types and explicit immutable world inputs. Unreal
adapters convert `UObject` settings/assets into those inputs and convert mesh results back to
Unreal types. The standalone loader maps its JSON snapshot into the same inputs. No Unreal headers,
reflection macros, `UObject`, or host allocator should cross the library boundary.

## Plugin integration

Build the core as one C++20 static library and link it from both the standalone viewer and the
VoxelForge Unreal module. The plugin keeps ownership of asset loading, worker admission,
cancellation, collision, game-thread mesh application, and per-frame upload budgets; workers call
the shared density and meshing API with immutable contexts. The standalone keeps its D3D11 renderer
and JSON loader and calls the same API.

## Preventing drift before extraction

Until the move lands, keep the standalone copies synchronized from the plugin source with a small
manifest of shared files and a checked sync script. The script should compare hashes and refuse an
ambiguous two-sided edit. Run the exported 3,436-sample bitwise parity corpus after every density
change, then remove the duplicate source only when both hosts build against the shared library.