Presentation is loading. Please wait.

Presentation is loading. Please wait.

By Eugene Adams.  Vertices  Edges  Faces  Polygons  Meshes  2D co-ordinates  3D co-ordinates.

Similar presentations


Presentation on theme: "By Eugene Adams.  Vertices  Edges  Faces  Polygons  Meshes  2D co-ordinates  3D co-ordinates."— Presentation transcript:

1 By Eugene Adams

2  Vertices  Edges  Faces  Polygons  Meshes  2D co-ordinates  3D co-ordinates

3 A vertex is the singular form of vertices. The term is used in geometry to describe the corner point of a shape: In laymans terms, the point at which a line either terminates or is intersected is a vertex. In computer graphics a vertex is associated not only with the three spatial coordinates which dictate its location, but also with any other graphical information necessary to render the object correctly.

4 On the Tetrahedron to the left, I have circled all of the vertices on the shape. Being a point on a shape, a vertex has no standardised form and changes according to the shape it is a part of.

5 In geometrical terms, an edge is a 1 dimensional line that connects two 0 dimensional vertices. When a minimum of 3 vertices are combined with a minimum of 3 edges, a 2D polygon (a Triangle in this case) or ‘face’ is created. Adding in a minimum of 1 more vertex and 3 more edges will transform the 2D polygon into a 3D polyhedron (in this case a Tetrahedron). This means that to create a 3D shape, a minimum of 4 vertices and 6 edges are required.

6 2 vertices connected by a single edge. 3 vertices and 3 edges creating a face or triangular polygon. 4 vertices and 6 edges creating a tetrahedron.

7 The term polyhedron is a greek term meaning “many faces”. Any 2D shape can be a face, combining several to create a polyhedron (e.g. 6 squares can combine to create a cube), thus making the term very appropriate. A face is created using 3 or more vertices and 3 or more edges in a closed pattern.

8 A single face (or ‘hedra’), in this case a square. A combination of 6 sqares to create a cube. Being made of 6 faces, the cube is thus a hexahedron.

9 The word “polygon” is derived from the Greek words “poly” meaning “many”, and “gonia”, meaning “knee” or “angle”. In moodern geometry, however, a polygon is usually defined according to its amount of sides rather than its angles. A polygon is always 2D, and many polygons can be used as faces to create 3D Polyhedrons. A polygon is composed of a closed circuit of vertices and edges, with a minimum of 3 vertices and 3 edges required.

10 A polygon mesh is a combination of vertices, edges and faces that form a Polyhedron. The faces used are usually triangles to simplify rendering, though (in theory) any shape can be used.

11 A dolphin made using a triangle mesh.

12


Download ppt "By Eugene Adams.  Vertices  Edges  Faces  Polygons  Meshes  2D co-ordinates  3D co-ordinates."

Similar presentations


Ads by Google