3D Modeling: Deforming and non-deforming objects

In a 3D environment anything can be modelled from a humanoid to a building. However, there are two types of modelling that are put into two categories: Deforming and non-deforming. Below are examples and explanations of what the two categories are in more depth.

Deforming

Objects in a 3D environment that move freely without rigidness or stiffness (unless exaggerated) are what's called deforming objects. These type of objects included are humanoids, animals and some organic life.

As you can see on the left, all of these rigs have something in common: limbs. Each model has limbs that can move quite realistically which also affect the mesh once it is bound to it. Objects that deform would also need to be weighted, which stops unnecessary movement in areas that should not be affected (e.g. a character model that has not been weighted has been bound to a rig. The arm moves and so does part of the body where it isn't supposed to.)

Non-deforming

When an object that does not bend but may still have a rig attached to it exists in a 3D environment, it is a non-deforming object, meaning it doesn't bend or stretch at all. Some examples of non-deforming objects include vehicles, armour on a human/humanoid character, and even some objects that act like an arm. Below are a couple of examples of what non-deforming objects look like in the 3D environment.

The dumper truck and the character model may not have obvious things in common like a deforming object would but what they do have in similarity is that they have non-deforming properties. The dumper truck has a rig to keep the skeletal structure of it in place and also an arm for the lifting of the box whereas the armour doesn't have its own rig but what it does do is not bend and stretch when moved because it is strictly weighted to the corresponding body piece (e.g. the arm has a wrist pad that doesn't bend when the hand is moved).