1. Generative Music By: Ryan Bone, Andrew Reed, Kevin Ekeberg, Hector Medina- Fetterman, Chase Plante

2. What is Generative Music? ●Constantly changing ●Created by a system

3. Types of Generative Music ●Structural ●Behavioral ●Creative ●Emergent

4. History ●3000-1100 BC o Wind chimes

5. History ●15th Century o Multi-mode pieces  Missa cuiusvis toni (Mass in any mode), Johannes Ockeghem

6. History ●18th Century o Musikalisches Würfelspiel (musical dice game)  scripthica.com scripthica.com

7. History ●20th Century o Algorithmic Generation  Stochastic  Grammar-based  Evolutionary  Learning systems  Hybrid systems

8. Grammars ●Grammars have been used in music theory and analysis since the 1980s ●By converting grammatical strings to sounds, pitch, and durations, music can be formed

9. L-Systems ●A type of rewriting system and formal grammar ●Developed in 1968 by a dutch biologist ●They can be used for many applications, ranging from generating fractals and trees, to music and terrain

10. L-Systems The Grammar can be represented as the following tuple G = (V, α, R) where ●V is the alphabet, or the set of symbols in the grammar ●α is the axiom, or initial state of the system. This a string made of symbols from V. ●R is a set of replacement rules that replace one symbol string with another. o For example. A → BCD would tell you to replace the symbol A with BCD when you encounter it o If a character does not have a rule we don’t do anything with the symbol

11. L-Systems L-Systems are processed from left to right. Given the rules: R1: A → BCD R2: B → E R3: C → A and the Axiom “A” we can get the following strings over 5 iterations IterationString 1A 2BCD 3EAD 4EBCDD 5EEADD

12. L-Systems ●Using this deterministic context-free grammar, we would not be able to generate randomness. ●We can add randomness by assigning more than one rule to a symbol, and then giving the rule a probability of occurring. This is called a stochastic grammar ●Using this framework, unique yet “similar” strings can be formed.

13. L-Systems ●We’ve generated strings, but now need to turn it into music ●By assigning a sound to each symbol, music can be generated ●Complexity can be added by adding symbols that denote duration and pitch

14. Generative Grammar Examples ●http://www.pawfal.org/dave/blog/2008/12/l-system-music-revisited/http://www.pawfal.org/dave/blog/2008/12/l-system-music-revisited/

15. Generative Music Software ●SSEYO Koan Pro (1994 - 2007) ●Intermorphic o Noatikl (2007 - present)  Replaced Koan o Mixtikl (2004 - present)  Portable solution ●Unity o G-Audio Editor Extension

17. Generative Music Software

18. Games with Generative Music ●Emergent - Beat Buddy by ThreaksBeat Buddy by Threaks ●Behavioral - January by DisasterpeaceJanuary by Disasterpeace

19. Xenochrony Example Frank Zappa Rubber Shirt Sheik Yerbouti 1979

20. Xenochrony “Strange synchronicity” A product of confirmation bias

21. Xenochrony in Games Ambient exploration music Rhythm heavy combat music Example

22. Vertical Layering Definition of layering- “Recording (or playing) a musical part with other several similar sound patches playing simultaneously to add more body or fullness to the recording.” Definition of vertical - “indicates a simultaneous event such as the sounding of several concurrent notes in a chord” In other words, the technique of vertical layering is to use distinct tracks or parts and play/stop them at different intervals on top of one another to create different moods depending on a variety of variables (Ex: start/end of combat, scripted moment).

23. Vertical Layering Vertical Layering is used due to its versatility & adaptive nature with generated music. Depending on the number of tracks you use, you can create the same song but with different emotional hooks depending on which track the listener hears first. Demo:

24. Vertical Layering There are two different techniques for Vertical Layering: Additive- All of the tracks are designed to be played together at once or with a select group of other tracks. The music will still sound good if certain tracks are or are not playing. Interchange- Some of the tracks are designed to be swapped with other tracks. Adding layers freely is not the goal here, but it is possible should the composer allow it.

25. Horizontal Resequencing Definition - the method by which pre-composed segments of music can be re-shuffled according to a player’s choice of where they go in a storyline or environment. Horizontal refers to the passage of time Resequencing is the reordering of tracks This uses tracks that “interrupt” one another in order to convey something to the player, such as how much time is left on a button press/power-up. The “interrupt” track is designed to mix in and out with a main track (or be a part of the main track) depending on the current state of gameplay.

26. Horizontal Resequencing & Vertical Layering Game Example Game: Super Mario Galaxy 2 Level: “Saddle Up With Yoshi” Composer: Koji Kondo & others

27. References Grammar Based Music Composition http://www.csse.monash.edu.au/~jonmc/research/Papers/L-systemsMusic.pdf http://www.csse.monash.edu.au/~jonmc/research/Papers/L-systemsMusic.pdf Temporality, Intentionality, and Authenticity in Frank Zappa’s Xenochronous Works http://researchblog.andremount.net/?p=476#2f Modeling Plants with Lindenmayer Systems http://www.allenpike.com/modeling-plants-with-l-systems/ http://www.allenpike.com/modeling-plants-with-l-systems/ 3d Lindenmayer Systems http://www.geocities.ws/gplatl/LSystem/LSystem.html http://www.geocities.ws/gplatl/LSystem/LSystem.html A Composer’s Guide to Game Music http://winifredphillips.wordpress.com/2014/03/06/a-composers-guide-to-game-music-vertical-layering-part-1/http://winifredphillips.wordpress.com/2014/03/06/a-composers-guide-to-game-music-vertical-layering-part-1/ Music Dictionary http://www.music-dictionary.org/Layeringhttp://www.music-dictionary.org/Layering

28. Questions?