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Convert FBX, OBJ, glTF and GLB models into USD components

A model you buy or export from another application usually arrives as FBX, OBJ or GLB, with its textures next to the file or packed inside it. For Solaris it has to become a USD component: each texture wired to the right material, levels of detail and a proxy. Everything, the CGfield conversion application, reads the materials the file declares and delivers one USD component per model.

Supported files

Everything reads .fbx, .obj (with its .mtl), .gltf and .glb files directly, Draco-compressed glTF included, as well as USD files (.usd, .usda, .usdc, .usdz). Files in .blend, .abc, .ply and .stl format go through Blender, run in the background, which converts them once to GLB. The component is written in meters, Y-up: the unit and up axis an FBX declares are read from the file, and the unit of an OBJ, which the format does not declare, is inferred. If a model has the wrong size, the side column lets you give it its real size from one known dimension, in mm, cm or m, with proportions kept.

Materials read from each format

Everything reads the material table each format carries: the Texture nodes and their connections in an FBX, the .mtl of an OBJ, the materials of a glTF. It therefore knows which texture goes on which channel of which material, including in a model with several materials. Textures embedded in a GLB or an FBX are extracted, and the glTF texture that packs roughness and metalness is split as the specification defines.

An FBX exported from 3ds Max with Corona, V‑Ray, Arnold or Physical Material materials is read too. Textures an FBX does not declare are looked up in its folder by name (basecolor, normal, roughness…). When Everything had to guess the conventions of a source it does not know, the asset card shows the “unverified” label: the export works, but check the render.

Steps

  1. Install the CGfield launcher with a free account, then Everything.
  2. Drag your FBX, OBJ, glTF or GLB files, a ZIP archive or the folder that holds them into Everything. Each recognized asset becomes a card in the gallery.
  3. In the Delivery section, turn on “USD component”, then choose the engines: MaterialX for Karma, and Arnold or V‑Ray if needed.
  4. Choose the output folder and start the export.
  5. In Solaris, add a Reference node on the component’s .usd file, pick the lod variant you want and render with Karma.

What the USD component contains

Each model becomes a self-contained folder: Asset.usd (the component, with its payload), payload.usdc, geo.usdc, mtl.usdc, the textures folder and a thumbnail, with relative texture paths. The material is written as UsdPreviewSurface and for each engine you tick: MaterialX, which Karma, Arnold and V‑Ray all read, or the native Arnold or V‑Ray network; when several engines are ticked, each one becomes a variant of the shader variantSet. The same component also loads in Maya through the Maya USD plugin.

Levels of detail are lod variants (foreground, midground, background) that cap the texture resolution: by default the foreground keeps the source, the midground goes down to 1024 pixels and the background to 256. The proxy, a lighter geometry with the proxy purpose, is shown in the viewport instead of the render. A file that holds a set of separate pieces, such as debris, gives one geo variant per distinct piece; a model made of several parts stays a single component. After writing, Everything reopens the component and checks that every mesh has its material and that every referenced texture exists.

Good to know

Everything runs on 64-bit Windows 10 and 11. For an FBX, OBJ, glTF, GLB or USD file, the conversion needs no other software; .blend, .abc, .ply and .stl files need Blender installed on the machine. The FBX must be binary, and only its static geometry is read, without animation or skinning. UDIM textures are not supported, and outside glTF a texture that packs several channels (ORM) is not split. A material whose textures cannot be found is flagged by a warning on the asset card.

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