Stage3d Study Notes (1): Introduction to 3D terms

Mesh)

In 3D, all visible models are called grids. A grid is created by modeling software such as 3dmax and defines the shape of a 3D object. A grid consists of multiple polygon.

 

Polygon)

A polygon is the smallest unit of a grid. In most cases, it is a triangle. All shapes in the 3D world are composed of multiple polygon. A polygon is composed of multiple vertices.

 

Vertex)

A vertex defines the shape of a polygon. For example, a quadrilateral can be defined for four points with different planes in a space. A triangle can be defined for any three different points in space.

 

Texture)

To add an image to a mesh, we need an image that overwrites the mesh surface. This image is called a texture;

 

UV

UV coordinates are used to represent a point in the material. The horizontal direction is u, the vertical direction is V, and the value is 0 ~ 1. Each vertex of each polygon corresponds to a UV coordinate, so that the texture image can be mapped to each polygon.

 

Vector)

A vector is used to record the direction and length.

 

Normal)

The normal is a unit vector directly penetrating the plane, that is, the normal on the plane is a vector perpendicular to all vertices on the plane. A normal can be used to represent a plane.

 

Matrix)

The grid in the space can be easily transformed (scaled or rotated) through a matrix ).

 

Shader)

The colorant provides programmable features. By writing different colorant, you can achieve different 3D effects.

 

Vertex shader)

Each vertex will execute the code of the shadow once.

 

Fragment shader)

Each pixel executes the code of the shadow once.

Stage3d Study Notes (1): Introduction to 3D terms