Evolutionary systems & genetic algorithms

* A way to select genotypes based on their scores and then modify or recombine them for expression

* A way to select genotypes based on their scores and then modify or recombine them for expression

* A way to express genotypes to create phenotypes

* A way to express genotypes to create phenotypes

== Types of Genetic Representations ==

== Types of Genetic Representations ==

* '''''Fixed Parametric''''' - A genotype that uses a fixed number of parameters that map into phenotypical characteristics in a one-to-one manner. The complexification capacity of this system is highly constrained.  

* '''''Fixed Parametric''''' - A genotype that uses a fixed number of parameters that map into phenotypical characteristics in a one-to-one manner. The complexification capacity of this system is highly constrained.  

* '''''Reproductive Mechanical''''' - Such a system is similar to the previous one, with the significant addition that within a single individual a machine may also create another machine, reproduce itself, or contribute to an emergent machine at a higher level of complexity and scale. This genetic representation offers the greatest complexification potential.

* '''''Reproductive Mechanical''''' - Such a system is similar to the previous one, with the significant addition that within a single individual a machine may also create another machine, reproduce itself, or contribute to an emergent machine at a higher level of complexity and scale. This genetic representation offers the greatest complexification potential.

**And this is, in fact, the kind of genetic representation found in nature. There is an upwardly layered increase of complexity as DNA creates proteins, proteins organize to create organelles, organelles organize to create cells, cells organize to create organs, and so on.

**And this is, in fact, the kind of genetic representation found in nature. There is an upwardly layered increase of complexity as DNA creates proteins, proteins organize to create organelles, organelles organize to create cells, cells organize to create organs, and so on.

== Practical Notes for Computer Artists ==

== Practical Notes for Computer Artists ==

In addition the rate of mutation may be a genetic variable. This provides some relief in deciding what the mutation rate should be. The optimal mutation rate will then evolve. It's even possible that the mutation rate will self-adjust over time. Typically at the start the mutation rate should be higher (randomization) than it is later (when fine tuning). It's worth noting that some cases have been found in nature where the mutation rate increases in response to increased environmental pressure. This too could be simulated by calculating the mutation rate as a function of both genetics and environmental pressure.

In addition the rate of mutation may be a genetic variable. This provides some relief in deciding what the mutation rate should be. The optimal mutation rate will then evolve. It's even possible that the mutation rate will self-adjust over time. Typically at the start the mutation rate should be higher (randomization) than it is later (when fine tuning). It's worth noting that some cases have been found in nature where the mutation rate increases in response to increased environmental pressure. This too could be simulated by calculating the mutation rate as a function of both genetics and environmental pressure.

  010<font color="red">0</font>      XOR      011<font color="red">1</font>

  010<font color="red">0</font>      XOR      011<font color="red">1</font>

<span style="font-size:larger">Image synthesis</span>

<span style="font-size:larger">Image synthesis</span>

Basically the expression is parsed into a tree structure, and then subjected to mutations, or a form of crossover by substituting entire branches of the tree. An equivalent implementation can be done by using text oriented regular expression processing techniques. The resulting phenotype is an image computed pixel by pixel by evaluating each expression substituting the specific (x,y) coordinate.

Basically the expression is parsed into a tree structure, and then subjected to mutations, or a form of crossover by substituting entire branches of the tree. An equivalent implementation can be done by using text oriented regular expression processing techniques. The resulting phenotype is an image computed pixel by pixel by evaluating each expression substituting the specific (x,y) coordinate.

* Image processing or video processing can be done by calculating pixel values as a function of (x,y,i,t) where i is the value of the image channel and t is time.

* Image processing or video processing can be done by calculating pixel values as a function of (x,y,i,t) where i is the value of the image channel and t is time.

== Interactive Genetic Art Installation ==

== Interactive Genetic Art Installation ==

== More Examples ==

== More Examples ==

* Matt Lewis - [http://accad.osu.edu/~mlewis/aed.html Evolutionary Design Links]

* Matt Lewis - [http://accad.osu.edu/~mlewis/aed.html Evolutionary Design Links]

* Craig Reynolds - [http://www.red3d.com/cwr/evolve.html Evolutionary Computation Links]

* Craig Reynolds - [http://www.red3d.com/cwr/evolve.html Evolutionary Computation Links]