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<2023-02-17 Fri>

Texture maps

Texture mapping refers to the method of mapping a 2D image (a texture) onto a 3D model. In its simplest form, the texture maps colored pixels onto the surfaces of the model using UV coordinates.

Types of maps

  • Diffuse map: An image that represents the color inside the flat surfaces of an object. When the size of the texels (texture pixels) is not equal to the size of the pixels on the screen, texture filtering methods are used to determine which pixels of the texture should be sampled and how.
  • Albedo map: These correspond to a diffuse map without any lighting information in it.
  • Height map: A grayscale image representing the surface elevation at each point. They range from 0 (lowest point) to 1 (highest point). They are also used outside of computer graphics.
  • Bump map: Refers to the usage of a heightmap to create shadows inside the flat surfaces of the model. The illusion usually breaks when viewing the material at an angle.
  • Displacement map: Refers to the usage of a heightmap to create displaced geometry on the flat surfaces of an object.
  • Normal map: An RGB image encoding the normal vectors on the flat surfaces of an object. The RGB components correspond to the XYZ coordinates. However, the orientation of the coordinate axes depends on the space that was used. The most commonly used encoding is tangent space.

Others:

  • Ambient occlusion (AO) maps
  • Specularity maps
  • Roughness maps or gloss maps
  • Metallness maps
  • Transmission maps
  • Emission maps
  • Subsurface color maps
  • Alpha maps
  • Position maps