Rendering

Rendering is the final process of creating the actual 2D image or animation from the prepared scene. This can be compared to taking a photo or filming the scene after the setup is finished in real life. Rendering may take from fractions of a second to days for a single image/frame.

We are able to create either photo-realistic rendering, or animation. We can also produce 3D rendering, the stereoscopic computer graphics process of automatically converting 3D wire frame models into 2D images with 3D photorealistic effects.

Models of reflection/scattering and shading are used to describe the appearance of a surface.

• Reflection/Scattering - How light interacts with the surface at a given point
• Shading - How material properties vary across the surface

Shading

Shading addresses how different types of scattering are distributed across the surface. A simple example of shading is texture mapping, which uses an image to specify the diffuse colour at each point on a surface, giving it more apparent detail. 

Transport

Transport describes how illumination in a scene gets from one place to another. Visibility is a major component of light transport.

Projection

The shaded three-dimensional objects must be flattened so that the display device - namely a monitor - can display it in only two dimensions, this process is called 3D projection. This is done using projection and, for most applications, perspective projection. The basic idea behind perspective projection is that objects that are further away are made smaller in relation to those that are closer to the eye. Programs produce perspective by multiplying a dilation constant raised to the power of the negative of the distance from the observer.

We are using CAD applications where scientific modelling requires precise measurements and preservation of the third dimension.