OBJ and MTL

MTL materials and PBR extensions

When opening an OBJ file, Solidly automatically resolves the companion .mtl library declared by mtllib statements and loads referenced texture maps from adjacent directories.

Beyond traditional Phong and Lambert definitions, Solidly evaluates modern physically based extensions written to MTL files. Materials render under HDR environment lighting with support for roughness, metallic, surface sheen, clearcoat, anisotropy, and transmission parameters, alongside per-vertex colours authored in v x y z r g b syntax. Solidly also displays line and point primitives alongside polygonal faces.

Material reconstruction and loose textures

Exported OBJ assets frequently detach from their texture paths or ship with unreferenced image files. Solidly scans the surrounding directory, analyses filenames and image contents to identify texture channels, and groups compatible images into candidate materials matched to the file's declared material slots.

Suggested materials appear as interactive cards in the Materials tab. Textures can be bound across the model using Merge Suggested, or mapped by dragging cards directly onto mesh surfaces in the viewport. Assigned materials update the companion .mtl library upon saving.

File structure and geometry inspection

Solidly's Info tab provides an immediate technical breakdown of the file, detailing object and group counts, line and point elements, vertex and index totals, and authored header comments.

In the Resources tab, Solidly maps the complete internal structure according to the format's own schema, organising named objects, groups, vertex attribute arrays, smoothing groups, and polygonal face definitions into a navigable tree.

To diagnose geometry and shading discrepancies, Solidly provides real-time visualizers in the Render tab to inspect surface normals, tangents, face orientation for reversed winding, UV coordinate distribution via checker patterns, and individual material channels in isolation.

Material configuration and PBR parameters

The Materials tab organises every MTL material into a dedicated card displaying surface factors, texture bindings, opacity, normal map strength, and emissive properties. An MTL PBR Extensions section exposes controls for metallic, roughness, transmission, clearcoat, surface sheen, and index of refraction. Edits reflect immediately in the viewport, and any material can be reverted to its disk state at any point.

New materials can be added to the model and bound by dragging cards onto surfaces in the viewport. Each card also includes a Descriptors disclosure, detailing authored MTL statements and texture file assignments.

Mesh utilities and file saving

Solidly includes dedicated geometry tools to split element groups into independent objects, reverse face winding, recalculate vertex normals, generate tangents, and compute UV unwraps for untextured surfaces. File and partition comments can also be reviewed and updated through a structured metadata inspector.

Saving updates the original OBJ and MTL files directly. The Save As command consolidates the model into a clean package folder containing the .obj, its companion .mtl, and all referenced texture maps.