Pattern/Texture Mapping

Adding details or features (variations in color or texture) to surfaces.

Pattern Mapping Technique -- Modulate the surface color calculated by the reflection model according to a pattern defined by a texture function. (This could be a digitized image or a procedurally-defined pattern.)

2-D Texture function: T (u,v)

Inverse Pixel Mapping (Screen Scanning):

For each pixel on screen ( xs , ys )

-Compute the point (x,y,z) on closest surface that projects to the pixel and determine its color from a reflection model (e.g., raytracing).

-Calculate the (u,v) that corresponds to (x,y,z) (inverse mapping).

-Modulate the color of ( xs , ys ) according to the value of the texture function T(u,v) at point (u,v).