3d Model: Coin

Coin

I created the coin as a very simple model. It is the complicated textures that add the details needed to make the distinction that you are looking at a coin.

Model

The first thing I did was make a spline that traces the contour of the coin along it's radius. The spline is just a line in 3d space that can be used to create a 3d model.

The spline is then rotated around it's axis to create the surfaces of the coin. These surfaces are mirrored to get the other side of the coin. This is the simplest kind of model that can be created.

Textures

By projecting image files onto the flat side of the coin, The details of the surface are described. The following illustrates these techniques.

Bump map

The bump map describes the subtleties in the shape of the surface. Areas of the bump map that are dark dent the surface, while areas that are light raise bumps in the surface.

Color Map

The color map describes the color of the object across it's surface. Even a simple object such as a coin which in theory is one color throughout gets tarnished over time.

Specular Map

The specular map determines how much light can be reflected from the surface at any point on the coin. Subtle variations in this map help to add believablility to the appearance of the coin.

Final

When these maps are combined on the surface, they work together to create a believable coin. Notice that the raised parts on the bump map effect how much tarnish color there is on the coin, and how much the specular map shines through.