### EXAMPLE OF 3D EVOLUTIONARY ART

Phenotype:

Ellipse, width 80, height 50, depth 4, rotated by 90 degrees

Spiral, radius 40, curliness 4, depth 6, shifted horizontally by 50, vertically by -20

Spiral, radius 40, curliness 4, depth 6, shifted horizontally by 50, vertically by -20, rotated 90 degrees

Spiral, radius 40, curliness 4, depth 6, shifted horizontally by 50, vertically by -20, rotated 180 degrees

Spiral, radius 40, curliness 4, depth 6, shifted horizontally by 50, vertically by -20, rotated 270 degrees

Fixed structure (embryology) using Shape Description Language:

 Table = { Ellipse ( width, height, depth ) YZ_Rotate ( angle ) } { Leg X_Shift ( distance ) Y_Shift ( distance ) Rotate&Duplicate ( angle, #duplicates ) } Leg = Spiral ( radius, curliness, depth )

Genotype:

 80 50 4 90 40 4 6 50 -20 90 4 width height depth angle radius curliness depth distance distance angle #duplicates

Figure. Evolving 'artistic tables'.

Returning once again to the 'table' example, the figure (left) shows the type of primitive shapes an Evolutionary Art system might use to represent forms. The figure (right) shows an 'artistic table' generated from such shapes. As this example shows, it is quite common for the artist to employ a Shape Description Language to specify the fixed structure of the designs to be evolved. In the example, each 'artistic table', must be constructed from an ellipse and a variable number of differently positioned and rotated swirls. This structure then defines how many genes will be evolved by the system, and how the values of the genes will be used to generate the phenotypes, i.e. the Shape Description Language defines the genome and embryology for Evolutionary Art Systems. By evolving the values of the genes, a number of unusual and hopefully aesthetically pleasing designs (some of which may behave as tables) will emerge.

Evolutionary Art is an effective way of creating highly original and unusual pieces of art, but it is rarely used to generate anything as practical as a table. Since forms are not analysed for their functionality (although users may be able to choose forms which appear more functionally valid than others), the output from Evolutionary Art systems is usually attractive, but non-functional. In addition, the choice of 'artistic' primitive shapes (swirls, tori, ellipses) often seems inappropriate for the representation of useful designs.