This glossary of PBR and 3D terms is a working vocabulary, not a textbook. Use it when a tutorial says “linear roughness” or “dielectric” and you want a one-paragraph meaning. Terms match how Blender, Unreal, Unity, and glTF actually behave. For full lessons, use the linked guides and the Locker3d CC0 texture library.
Surface maps
Albedo / base color — Surface pigment with no lighting. sRGB. Diffuse — Older color map; often had baked light. Prefer albedo. Roughness — Micro-surface irregularity; high = matte, low = sharp reflections. Linear. Glossiness — Inverse of roughness; invert if a pack is gloss-based. Metalness / metallic — 0 = non-metal, 1 = metal in the metalness workflow. Specular (workflow) — Alternate PBR that stores reflection color separately; common in some V-Ray setups. Normal map — RGB data that fakes surface direction. Needs a Normal Map node. Height / displacement — Grayscale elevation for parallax or true displacement. AO — Ambient occlusion; soft cavity shadow, optional. ORM / RMA — Packed maps (occlusion, roughness, metalness in RGB). Details: map guide and metalness vs specular.
Lighting and rendering
PBR — Physically based rendering. BRDF — The function that describes how a surface reflects light; Principled BSDF is a practical BRDF. IBL / HDRI — Image-based lighting from a high-dynamic-range photo of an environment. Path tracing — Offline method (Cycles, V-Ray, Corona) that traces light paths for GI and reflections. Rasterization / real-time — Fast approximation (Eevee, game engines). Denoiser — Filter that cleans Monte Carlo noise. Exposure / tone mapping — How HDR lighting becomes an 8-bit image. Render — The process of turning a 3D scene into a 2D image; see what is a render.
Geometry and UVs
UV unwrap — Flattening a mesh to 2D so textures stick. Texel density — Pixels per meter; keep it even across a scene. Seamless / tileable — A texture that repeats without a visible edge. Triplanar — Projects textures from X/Y/Z to hide seams on rocks and terrain. LOD — Level of detail; simpler mesh or smaller mips far from camera. Nanite — Unreal’s virtualized geometry. Virtual texture — Paged unique or landscape textures. glTF / GLB — Khronos runtime format with metallic-roughness PBR. USD — OpenUSD scene interchange.
Licenses and files
CC0 — Public-domain dedication; no required credit; commercial OK. Locker3d uses this model. CC-BY — Free to use if you credit the author. Royalty-free — Usually paid once; still read the PDF. sRGB vs linear / Non-Color — Color space for images; albedo is sRGB, data maps are linear. PNG / JPEG / EXR — PNG for lossless maps, JPEG for heavy albedo, EXR for high-bit lookdev. License reading: CC0 textures and texture formats.
Workflow words you will hear
Lookdev — Lighting and materials until the asset looks right. Bake — Transfer lighting or detail into textures. Instance — Reuse a material or mesh without duplicating data. Hero asset — Close-up object that deserves 4K maps. Dielectric — Non-metal (plastic, wood, stone, glass). Browse examples in wood, stone, and metal. For a learning order, see texture fundamentals and the blog.
Frequently asked questions
What does PBR stand for?
Physically based rendering: a lighting and shading model that uses measurable surface properties (albedo, roughness, metalness or specular) so materials look consistent under different lights and engines.
What is the difference between albedo and diffuse?
Albedo is the lighting-free base color used in PBR. Older “diffuse” maps often included baked shadows or AO. For new work, use a clean albedo and let the renderer create shading.
What does CC0 mean for textures?
CC0 is a public-domain dedication. You can use, modify, and redistribute the textures, including commercially, without required attribution. You cannot claim exclusive ownership of the original maps.