meshy-dev/meshy-dcc-adapters/meshy-unreal

Meshy Unreal handoff

Use session to confirm the editor PID, project, open level and unsaved maps and assets. dirty is null when Unreal cannot report unsaved state; treat that as unsaved. engine_unsaved lists engine content that got dirty on its own (a material gaining a usage flag); it is not the user's work, it does not count as unsaved, and it must never be saved.

1. If session reports level_in_project: false (the editor opened an engine

template map), create a project level with unreal-level create_level, for example {"level_path": "/Game/Maps/Handoff", "template_path": "/Engine/Maps/Templates/Template_Default"} for sky, lights and a floor. Never save over an engine map.

1. Download the model with meshy and keep it on disk. A GLB carries its

textures. For an FBX, keep Meshy's PNGs next to it: <name>.png, <name>_normal.png, <name>_metallic.png, <name>_roughness.png.

1. import_model with source_path and a name imports into

/Game/Meshy/<name> and saves those assets. A GLB keeps Unreal's glTF PBR material. For an FBX, the texture set (found by name, or passed as textures) becomes one PBR material M_<name> on every slot, because Unreal's FBX material would read roughness as shininess. The model is placed with its base at location (default the world origin). The tool refuses a folder that already holds assets. Never repeat it when the outcome is unknown; inspect instead.

1. inspect_model with actor set to that name reads back vertices,

triangles, bounds, material slots and, per texture, the role it feeds, its sRGB, compression and green-channel flip. Unreal may build Nanite for a dense Meshy mesh (nanite: true); after the editor reloads it, vertex and triangle counts are the fallback mesh's, not the source's.

1. capture_model with the actor and a file_name renders

<project>/Saved/MeshyDcc/<file_name>.png, also while the editor is in the background. Imported Meshy models face +Y, and the views are relative to that: front looks at the face, three_quarter from the front left. Bindings are not visual proof; look at the capture before claiming the appearance is right.

1. Save the level with unreal-level save_level only when asked, then check

that session reports dirty: false.

To close an editor that meshy-dcc start-instance launched, use meshy-dcc stop-instance. Unreal would quit without asking to save, so the stop refuses while any map or asset of the project is unsaved, or when the editor cannot tell, unless the user agreed to discard it (--discard-unsaved).