Practical Algorithms for 3D Computer Graphics, 2nd Edition

74 3. Data structures for 3D graphics

name the vertex is associated with. The new structur e is shown in figure 3.4. A

basic version of a structure that specifies a polygonal su r face patch is illustrated

in figure 3.5.

Grandchild

Child

Parent

Head

Body

Left Foot

Left Leg

Hand

Arm

Figure 3.3: A hierarchical data structure for ed itin g and character animation.

p position vector of vertex

ν, µ su r face texture coordinates

x temporar y integer index

n number of adjacent vertices

V

adj

list of adjacent vertices

h

id

pointer to hierarchical element vertex is assigned to

Figure 3.4: Vertex data structure with hierarchical identifier.

V

id

list of vertex ids to which p oly gon ...