Why are matrices needed in Direct3D?

Question

C++ / C#

Why are matrices needed in Direct3D? Can they be replaced with arrays?

Answer 1

Number, vector and matrix are all arrays. Just the dimensions are different. A matrix can essentially be represented as a two-dimensional vector (two-dimensional array). Finite matrices can naturally be replaced by vectors (one-dimensional arrays) - for example, a 3x3 matrix is ​​​​replaced by a vector of 9 elements. But over time, you will get used to operating with matrices and they will be clearer for you.
And using a finite number of operations with matrices, you can perform rotation, scaling and other operations with shapes.
I recommend you read more about matrices. For many actions with them, the knowledge of high school is enough.
For example, habrahabr.ru/post/131931

Answer 2

how then without matrices to calculate the perspective and position of the bones of the animation of the mesh? to sort through each vertex manually?