Radient includes an OBJ scene importer registered as "obj". LoadScene() selects it automatically for .obj URIs, or it can be selected with RadientSceneLoadInfo::ImporterId = "obj".

RadientSceneLoadInfo LoadInfo;
LoadInfo.URI = "models/model.obj";
RefCntAutoPtr<IRadientSceneAsset> pScene;
RADIENT_STATUS Status = pAssetManager->LoadScene(LoadInfo, &pScene);

Scene loading uses the normal asynchronous asset pipeline. Referenced MTL files are resolved relative to the OBJ file's resolved URI. Image paths are resolved relative to the MTL file that declares them, through the configured asset resolver.

Geometry

Positions, texture coordinates, normals, and RGB/RGBA vertex colors are supported.
Faces may use separate position, UV, and normal indices, including negative indices. Triangles and simple planar polygons are supported; concave polygons are triangulated with Diligent's polygon triangulator.
Missing normals are generated. Smoothing groups share normals across UV seams; s off uses a separate face normal. Authored normals are preserved.
Object and group changes start mesh groups. Material changes produce primitive ranges within a mesh. The result contains one scene with identity-transform root nodes for its meshes.
Position units, coordinate axes, winding, and texture coordinates are preserved. Homogeneous positions are divided by W. There is no automatic axis conversion or V flip.

Lines, points, free-form curves, and surfaces are not rendered. Self-intersecting or non-planar polygons are outside the polygon triangulator's supported input. Malformed face indices and invalid numeric data fail loading with a diagnostic.

Materials

MTL materials are mapped to Radient standard materials:

MTL property	Radient property
Kd, d / Tr	Diffuse color and opacity (d takes precedence)
Ks	Specular color
Ke	Emissive color
Ns	Glossiness, approximated as 1 - sqrt(2 / (Ns + 2))
map_Kd	Diffuse texture, loaded as sRGB
map_Ks	Specular-glossiness texture, loaded as sRGB
map_Ke	Emissive texture, loaded as sRGB
norm	Normal texture, loaded as linear data

illum 0 uses an unlit material with Kd and map_Kd as its base color. Other illumination models use specular-glossiness shading; advanced reflection and refraction models are approximated. Opacity below one enables transparent rendering. Diffuse/specular colors and opacity are clamped to [0, 1]; emissive values are clamped to nonnegative values.

Texture -s, -o, and -clamp options control UV scale, offset, and addressing. For norm maps, -bm sets the normal scale. The specular-glossiness texture's alpha channel also multiplies glossiness; use opaque specular maps when this modulation is unwanted. Phong shininess and PBR glossiness are different shading models, so their appearance is approximate.

Height-map bump/map_Bump, separate opacity maps, and procedural material maps are not converted. Missing material libraries or unknown material names use the default material and produce a warning.

Failed texture sources use the standard material texture fallback when available. Returned texture handles retain their load failure status.