Model formats and Rhino blocks

Import a model#

Open the yellow + in Geometry Tree or open Geometry, then choose Import model & resources. Choose one model, or select the model together with its texture, BIN and MTL files. A ZIP can retain resource subfolders. Append to scene is the default import strategy. Import your shank, then import the head (or the reverse) to combine both in one scene. Each appended file appears directly under Scene root, beside the first file, with its internal hierarchy intact. Choose Replace imported models in Model orientation when you want to replace the imported sources. Both strategies keep studio-created primitives and lights. Before import, choose Y-Up or Z-Up in Model orientation. Y-Up is common for glTF; Z-Up is common for CAD. Use the source application’s axis convention. Cancel leaves the scene unchanged. The choice rotates only the source-model wrapper, preserving authored primitive and light placement. Change Model up axis in Scene Settings later if needed. Undo/Redo restores the source file, hierarchy and chosen orientation together; a failed import keeps the previous model and orientation.

3DM, GLB and glTF loader code is available from startup. The local Rhino runtime is warmed in the background. Other format loaders load only when their format is opened. Decoding runs locally; Studio does not send the model to a conversion service.

Formats#

There is no universal browser decoder for every CAD or proprietary application format. STEP, IGES, DWG, native Blender, 3ds Max and similar project files need conversion to a supported format. Extension support also does not guarantee every vendor extension or application-specific shader will translate.

Rhino Instances#

Save the 3DM with render meshes before importing. The Instances panel manages definitions and their direct/nested placements, retains unused definitions, and supports linked duplication, placement, replacement, shared edits and Make unique. Instances have an I badge in Geometry Tree. Definition members are edited explicitly through Edit shared; normal viewport selection chooses the outer placement.

Transforms retain their source precision, including signed scale and exact shear matrices. Members retain object layers and Parent/Layer/Chosen material settings. Source notices identify unavailable geometry and linked snapshots. External linked files are not automatically loaded or refreshed. Studio edits save in the project without modifying the original 3DM; NURBS/topology editing and 3DM writeback remain in Rhino. See Instances for operations, migration and limits.

Resources and limits#

Model packages are limited to 100 MB compressed/input size, 128 MB expanded and 4,990 imported nodes. A ZIP must contain one model unless Studio created its entry manifest. For glTF, include the BIN and referenced textures. For OBJ, include its MTL and images. Prefer a self-contained GLB for portability.

Only included local resources and embedded data are resolved. Missing resources, path traversal, ambiguous entry models, invalid geometry and unsupported formats produce an error before replacing the current scene. Remote resource URLs are not fetched. Texture decoding and proprietary format features can vary by browser and source exporter.

Save Project embeds the source file or package, so reopening does not depend on a local filesystem path. The Geometry Tree keeps source materials by default. Apply reusable scene materials to a compatible drawable object when you want an editable override. Instance roots accept material assignments for members using Parent inheritance. Use Edit shared for definition-member assignments.

Rhino layer editing#

Imported Rhino layers, including empty and nested layers, appear in Object Layers. Layer editing is independent of the object-parent tree and is saved in the Studio project. The original 3DM remains embedded unchanged; this release does not write Rhino files.

Rhino NURBS viewing#

Points, point clouds and curves are displayable, including single-point files. Missing surface meshes are retained as non-drawing source objects with bounds. Open NURBS for quality-controlled curve display, edges, control nets, local untrimmed previews and explicit Rhino Compute fallback for trimmed geometry. Generated display data travels with the unchanged 3DM in saved projects. CAD modeling and 3DM writeback remain in Rhino.

Import placement defaults#

Use Scene Settings → Drag Options before opening or dropping a model. Center imported model and Normalize model size are enabled by default; Longest dimension defaults to 3.4 preview units. Disable either independently to preserve the source placement or size. Each import records these choices, so later changes to Drag Options affect only future imports. The original source geometry remains available unchanged.

Rhino document grid settings#

3DM imports can supply document grid spacing, extent, major-line frequency and grid-axis visibility. Preferences → Grid → Use grid settings from 3DM is enabled by default; your stored device defaults remain unchanged. Dynamic cell sizing takes precedence over imported extent while enabled, and imported spacing follows model scale. Unsupported or malformed grid records fall back to Preferences. View-specific construction planes and snapping are not imported. See Render Preview grid.

Combining model files#

Append preserves existing material assignments, hierarchy edits and source coordinates. Each newly appended file is a separate root branch: moving, hiding or deleting the first imported file does not change the appended file. The newly appended branch is selected automatically. Existing saved nested imports keep their recorded hierarchy. The first import establishes the centering/normalization used by later files, so separately exported ring parts remain aligned. Select the correct up axis for each new file; a different axis is compensated for that file. Each import accepts one model plus its resources. The combined source package travels with .lumen and local document saves; Undo removes an append and Redo restores it. Combined input is limited to 100 MB, with a 128 MB expanded archive limit and the existing hierarchy limits.

Static GLB/glTF nodes that reuse a mesh appear as shared definitions in Instances and as placed copies in Instance Placements. Recognition uses source mesh identity, not matching names. Animated/skinned models and native GPU-instancing extensions retain their native rendering behavior.

Deleting all imported geometry clears the active import context for the next import, even if the previous source file is still available for Undo. You can import again into the same document without creating a new tab; studio-created geometry and lights remain intact.

Automatic gem import fixes#

Preferences → Import Fixes controls mirrored gemstone placements and reversed closed-mesh faces/normals. Both fixes default on and apply automatically when an internal-refraction Diamond material is used. A toast reports repairs. Original model files remain intact; disable a preference to inspect the original behavior. Open or nonmanifold meshes and animated/skinned geometry are not automatically reoriented. Faces in the viewport display menu shows cyan front faces, red back faces and magenta conflicting normals.