Textures

Texels

They are the smallest unit of a texture image. A texel maps to a point on a 3D surface via UV coordinates/texture pixels

UV mapping

Mapping 3D surface points to 2D texture coordinates

Name three mapping types

UV, planar, spherical, cylindrical, triplanar

How to fix textures that stretch?

Adjust UVs or use triplanar mapping

texture wrapping

How textures behave when UV > 1: repeat, mirrored repeat, clamp

magnification filtering

Choosing between texels when enlarging texture (nearest/linear).

minification filtering

Selecting texel values when shrinking texture; requires MIP maps

MIP map

Chain of precomputed scaled textures for level-of-detail

why MIP maps?

Remove aliasing, improve performance, smoother textures

normal mapping

A texture that alters surface normals to fake high detail

roughness mapping

Controls how blurry or sharp reflections appear in PBR

metalness mapping

Defines which parts behave like metal vs dielectric

environment mapping

Using skybox/HDR image to simulate reflections

displacement mapping

Actually moves geometry based on texture values

What does filtering prevent?

Aliasing, flickering, blocky textures

texture atlas

Many textures packed into a single image

Why HDR maps

Enables realistic global illumination and reflections

What defines texture detail level?LOD

Resolution, texel density, MIP levels

sampler

Shader component reading texel values

Why is UV unwrapping necessary?

Ensures correct mapping of textures to 3D geometry