public class DecalGroup
extends OrderedGroup

The DecalGroup node is an ordered group node used for defining decal geometry on top of other geometry. The DecalGroup node specifies that its children should be rendered in index order and that they generate coplanar objects. Examples of this include: painted decals or text on surfaces, a checkerboard layered on top of a table, etc.

The first child, at index 0, defines the surface on top of which all other children are rendered. The geometry of this child must encompass all other children, otherwise incorrect rendering may result. The polygons contained within each of the children must be facing the same way. If the polygons defined by the first child are front facing, then all other surfaces should be front facing. In this case, the polygons are rendered in order. The renderer can use knowledge of the coplanar nature of the surfaces to avoid Z-buffer collisions. If the main surface is back facing then all other surfaces should be back facing, and need not be rendered (even if back face culling is disabled).

Note that using the DecalGroup node does not guarantee that Z-buffer collisions are avoided. An implementation of Java 3D may fall back to treating DecalGroup node as an OrderedGroup node.