Special Challenges/Problems
Graphics renderers only handle straight lines so spherical data must be resampled.
Large data sets benefit from special data reduction/handling techniques.
Reference information allows surface features to be related to internal ones.
The shell is thick and close to the centre of the sphere, the angular component is important.
Perceptual factors make orientation, perspective and colour difficult to interpret.
Depth was not before a visual factor, originally 2D projections were used.
- New normalisation is needed.
- Cut planes are also 2D.
- Internal data may be self obscuring.