glTF and GLB

PBR materials and glTF extensions

Solidly implements the standard glTF metallic-roughness shading model under HDR environment lighting. Solidly's renderer handles advanced material extensions including clearcoat, surface sheen, volumetric transmission, glass dispersion, and thin-film iridescence.

Models packaged with geometry compression or modern texture containers decode during load. Solidly decompresses Draco, Meshopt, quantized meshes, and KTX2 Basis Universal textures directly into memory, opening production-ready web assets without pre-processing.

A detailed summary of supported material, geometry, and texture extensions appears in the glTF extension support reference table.

Animation playback and transport controls

When a file contains animation tracks, Solidly displays a transport bar directly over the viewport. Solidly's playback engine evaluates skeletal deformation on skinned meshes, adjusts morph target weights, and drives property transitions targeted by KHR_animation_pointer.

Individual animation clips include controls for timeline scrubbing, continuous looping, and playback speed adjustments from half speed to double speed. Files authored with multiple concurrent tracks display stacked controls to inspect each sequence independently.

Still frames from any point on the playback timeline can be captured at up to 8K resolution through Photo Mode.

File inspection and Khronos validation

The Info tab summarises the core technical properties of the file, detailing vertex and triangle totals, declared compression methods, extension requirements, and embedded metadata such as XMP packets. Solidly runs the official Khronos glTF Validator automatically upon opening a file, reporting syntax errors, specification warnings, and optimisation hints alongside their exact JSON pointers.

To isolate rendering issues, the Render tab provides dedicated diagnostic modes. Visualizers display surface normals, tangents, vertex colours, UV coordinates via checker patterns, and individual shading passes in isolation. Toggle switches on each active material extension allow direct before-and-after evaluations without modifying file data.

The Resources tab exposes the underlying file schema, organising scene nodes, mesh primitives, cameras, punctual lights, skinning bindings, and raw buffer accessors into a navigable tree.

Material configuration and variants

The Materials tab organises every material in the 3D model into an interactive card showing surface parameters, texture channel assignments, alpha modes, and backface culling options. Edits reflect immediately in the viewport, and individual materials can be reset to their disk state at any point.

The Add Extension menu adds supported Khronos extensions directly to an existing material card, including clearcoat, sheen, transmission, iridescence, and volume. Texture sampler parameters, such as wrapping modes, filtering behaviour, and KHR_texture_transform UV offsets, can be adjusted inside the Textures pool.

For models with KHR_materials_variants, Solidly allows creating new variant entries, switching active configurations, and assigning material overrides within the chosen variant set.

Scene graph editing and file saving

The Hierarchy panel provides complete access to the glTF node tree. Nodes can be reordered, reparented, renamed, duplicated, or deleted, and empty group nodes, directional or punctual lights, and perspective cameras can be inserted directly into the scene. Spatial transforms can be adjusted numerically in the Node tab or positioned interactively with viewport gizmos. Separate glTF or GLB files can also be merged into the active scene.

Mesh utilities can separate multi-primitive meshes into distinct nodes, invert surface normals, recalculate tangents, and generate missing UV coordinates. Metadata fields, including custom extras objects and XMP blocks, are editable through dedicated property fields.

Saving updates the original file while preserving its declared compression layout. The Save As command exports to either binary .glb with self-contained assets or standard .gltf with external buffers and textures.

Asset compression and delivery optimization

Solidly's compression pipeline generates optimized duplicates of GLB and glTF assets while keeping source files untouched. Mesh data can be quantized or encoded using Draco or Meshopt compression algorithms, while texture maps can be converted to WebP or Basis Universal KTX2 containers.

For web delivery, the default configuration pairs Meshopt geometry compression with KTX2 textures, which stay compressed in GPU memory during runtime.