# PLAYTEX AI PBR and Texture Glossary — cited sources

- Canonical page: https://www.playtex.ai/guides/pbr-glossary
- Data version: 1.0.0
- Reviewed: 2026-08-30
- Scope: This page defines terms and aliases. It does not replace map tutorials, measured material references, engine setup, or the live tools.

## Primary documentation

1. [Khronos glTF 2.0 Specification](https://registry.khronos.org/glTF/specs/2.0/glTF-2.0.html)
   - Version: glTF 2.0
   - Used for: Metallic-roughness material semantics, transfer functions, tangent-space normals, occlusion, emission, and channel layouts.
2. [Unity 6.1 Manual: Introduction to normal maps](https://docs.unity3d.com/6000.1/Documentation/Manual/StandardShaderMaterialParameterNormalMap.html)
   - Version: Unity 6.1 (6000.1)
   - Used for: Normal maps, bump and height distinctions, Y+ convention, tangent-space vector encoding, and flat-normal value.
3. [Unity 6 API: TextureImporter.sRGBTexture](https://docs.unity3d.com/current/ScriptReference/TextureImporter-sRGBTexture.html)
   - Version: Unity 6 (6000.0 documentation build)
   - Used for: sRGB sampling for color textures and linear sampling for non-color data textures.
4. [Unreal Engine 5.8: Physically Based Materials](https://dev.epicgames.com/documentation/en-us/unreal-engine/physically-based-materials-in-unreal-engine)
   - Version: Unreal Engine 5.8
   - Used for: Base Color, Roughness, Metallic, Specular, normalized ranges, and binary metal classification guidance.
5. [Unreal Engine 5.8: Using Texture Masks](https://dev.epicgames.com/documentation/en-us/unreal-engine/using-texture-masks-in-unreal-engine)
   - Version: Unreal Engine 5.8
   - Used for: Mask semantics, RGB channel packing, linear sampling, and the distinction between packed source data and runtime use.
6. [Godot stable: StandardMaterial3D and ORMMaterial3D](https://docs.godotengine.org/en/stable/tutorials/3d/standard_material_3d.html)
   - Version: Godot stable documentation checked August 2026
   - Used for: OpenGL-style normal orientation, green-channel conversion, and standard material inputs.
7. [Blender Manual: Principled BSDF](https://docs.blender.org/manual/en/latest/render/shader_nodes/shader/principled.html)
   - Version: Blender latest manual checked August 2026
   - Used for: Principled material inputs including base color, metallic, roughness, emission, alpha, and normal.
8. [Three.js: MeshStandardMaterial](https://threejs.org/docs/#api/en/materials/MeshStandardMaterial)
   - Version: Three.js current documentation checked August 2026
   - Used for: Metallic-roughness material inputs and renderer-facing texture roles.
9. [Khronos KTX 2.0 Specification](https://registry.khronos.org/KTX/specs/2.0/ktxspec.v2.html)
   - Version: KTX 2.0
   - Used for: Texture containers, mip levels, supercompression, and GPU-oriented texture delivery.

## PLAYTEX AI repository evidence

The evidence snapshot records the current UI and export contracts reviewed on 2026-08-30.

- The current workspace exposes seven output roles: albedo, normal, roughness, metallic, height, ambient occlusion, and emission.
- Blender, Godot, Three.js, and glTF presets use OpenGL normals with roughness output.
- The Unity preset uses OpenGL normals with smoothness output.
- The Unreal preset uses DirectX normals with roughness output.
- The glTF package writes roughness to G and metallic to B; its occlusion texture remains a separate R-channel input.

Limitation: This is a repository and UI contract snapshot, not a claim that every external engine project uses the same shader, packing, compression, or import defaults.