Explain the PBR workflow in Unity and the typical texture maps involved.

• A. PBR uses physically based rendering with maps such as Albedo (color) and Normal (bump) only.
• B. PBR uses Albedo, Normal, Metallic, Roughness, and Emission maps.
• C. PBR uses Albedo, Height, Ambient Occlusion only.
• D. PBR uses Albedo, Metallic only.

Answer: (B)

Physically based rendering builds material appearance from a set of textures that describe color, detail, and how light interacts with the surface. The Albedo texture provides the base color of the material. The Normal map adds fine surface detail by perturbing the surface normals, giving the illusion of bumps and grooves without extra geometry. The Metallic map determines whether the surface behaves like metal or a dielectric; metals reflect light differently and carry their color, while non-metals stay closer to their Albedo color. The Roughness map controls micro-surface roughness, influencing how sharp or blurred a reflection appears—rougher surfaces appear duller with softer reflections, while smoother surfaces produce clearer highlights. The Emission map defines areas that glow or emit light independently of lighting, useful for any self-illuminating parts of the material.

In Unity, these textures form the core set for a typical PBR workflow: Albedo, Normal, Metallic, Roughness, and Emission. Depending on the shader and pipeline, Metallic and Roughness can be in separate textures or packed together in a single map, but the concept remains the same. Additional maps like Height (for parallax effects) or Ambient Occlusion can be used to add extra depth and shading detail, but the five maps above are the essential ones for achieving realistic materials under PBR.