Geometry grouping and merging
In this section, we’ll look at two basic features of Three.js: grouping objects together and merging multiple geometries into a single geometry. We’ll start with grouping objects.
Grouping objects together
In some of the previous chapters, you already saw how you can group objects when working with multiple materials. When you create a mesh from a geometry using multiple materials, Three.js creates a group. Multiple copies of your geometry are added to this group, each with its own specific material. This group is returned, so it looks like a mesh that uses multiple materials. In truth, however, it is a group that contains a number of meshes.
Creating groups is very easy. Every mesh you create can contain child elements, which can be added using the add function. The effect of adding a child object to a group is that you can move, scale, rotate, and translate the parent object, and all the child objects will also be affected. When...
