3D Texturing Flashcards

What is 'tri-planar mapping' and when is it most useful?

Answer: A technique that blends three axis-aligned projections to texture a mesh without UV seams, useful for complex or procedural geometry

Tri-planar mapping blends textures projected along the X, Y, and Z world axes based on surface normals, eliminating UV seams on geometry like rocks, terrain, or procedurally generated meshes.

In Marmoset Toolbag's baking system, what does 'skew correction' help resolve?

Answer: Corrects tangent-space normal map artifacts caused by skewed or non-uniform UV stretching

Skew correction in Marmoset adjusts the normal map bake to account for skewed UV islands, producing accurate tangent-space normals even where UVs are non-uniformly stretched.

What does the 'Fresnel effect' govern in a PBR material, and how does it appear visually?

Answer: It describes how reflectivity increases at grazing angles, making surfaces appear more mirror-like near their silhouettes

The Fresnel effect (described by Schlick's approximation in PBR) causes nearly all materials to become highly reflective at grazing angles, which is physically accurate behavior.

When should you use a 'smart material' in Substance Painter versus creating a material from scratch?

Answer: Use a smart material when you want a preset collection of generator-driven layers (edge wear, dirt, etc.) that adapt to the mesh's baked maps

Smart materials in Substance Painter are self-contained layer stacks with generators that reference baked maps (AO, curvature, position) to intelligently place dirt, wear, and other effects on the mesh.

What is the key difference between 'hard edges' and 'smoothing groups' when preparing a mesh for normal map baking?

Answer: Hard edges and smoothing groups are different software representations of the same concept — edges where the shading normal transitions sharply

Hard edges (in Maya/Blender) and smoothing groups (in 3ds Max) are equivalent concepts — both define where surface normals are averaged continuously vs. split sharply, and both must align with UV seams for correct baking.

Which texture format preserves the most color information when used as a 16-bit file compared to an 8-bit PNG for gradient-heavy textures like height maps?

Answer: 16-bit TIFF or EXR

16-bit TIFF or EXR files store 65,536 discrete values per channel versus 256 in 8-bit, preserving smooth gradients in height maps without the visible banding that 8-bit files produce.

What does 'roughness remapping' (also called roughness calibration) accomplish in a texturing pipeline?

Answer: Adjusts the input roughness range to match the response curve of a specific render engine's BRDF

Roughness remapping rescales or curves the roughness values so that the perceived surface response matches the target renderer's BRDF, since different engines interpret the 0-1 range differently.