2010

Table Of Contents
Lesson 1: UV texture mapping
Introduction
There are several techniques for texture mapping 3D surfaces depending on
the surface type (NURBS, polygons, subdivision surfaces). Some techniques
involve preparing the surfaces for texture mapping. For example, when texture
mapping polygonal and subdivision surface types you need to understand
how textures are applied using UV texture coordinates.
UV texture coordinates, or UVs as they are more commonly called, are
two-dimensional coordinates that reside with the vertex component
information for a 3D surface. UVs control the placement of a texture map on
a 3D model by correlating the pixel position of the 2D texture map to the
vertex positions on the model, so that the texture gets positioned (mapped)
correctly.
For NURBS surfaces which have an inherent rectangular topology, the UV
texture coordinates are implicit. That is, the UVs reside in the same location
as the control vertices, so have a natural correlation to a rectangular shaped
texture map.
For polygonal and subdivision surface type models, which have an arbitrary
surface topology, the UVs can be explicitly created and modified to suit the
requirements of the texture map.
In this lesson youll learn the basic principles of UVs by applying (mapping)
an existing image (texture) to a simple polygonal model and creating and
Lesson 1: UV texture mapping | 363