Chapter 3. Tutorial 3: Creating and Editing Paths

Table of Contents
3.1. Introduction to Paths
3.2. Creating, Selecting, and Viewing PathInstances
3.3. Copying and Removing PathInstances
3.4. Editing PathInstances

This tutorial demonstrates the basic features of the Path, including creating, storing, examining, and editing Paths.

3.1. Introduction to Paths

A PathInstance (or a Path or PI) is an ordered collection of pitch groups. A pitch group, or a Multiset, is the simultaneous representation of pitch-space, pitch-class space, and set-class information for a collection of microtonally-specified pitches. This collection can be treated as an ordered or unordered collection, can be edited by transposition, replacement, or serial re-ordering, and can be used by one or more Textures to provide pitch materials that are then independently transposed and interpreted by the Texture and its ParameterObjects.

A PathInstance allows the representation of ordered content groups, and presents this representation as a multifaceted object. Paths can be of any length, from one to many Multisets long. A Multiset can be specified in terms of pitch class (excluding octave information with integers from 0 to 11), or in terms of pitch-space (including octave information with integers below 0 or above 11, or with register-specific note names such as C3 and G#12). A Multiset can also be specified as a group, set, or scale sequence such as a Forte set-class (Forte 1973) or a Xenakis sieve (Ariza 2005c). Finally, Multisets can be derived from spectrums and frequency analysis information provided from the cross-platform audio editor Audacity (enter "help audacity" for more information).

A Path can be developed as a network of intervallic and motivic associations. The interpretation of a Path by a Texture provides access to diverse pitch representations for a variety of musical contexts, and permits numerous Textures to share identical or related pitch information. The use of a Path in a Texture, however, is optional: a Path can function, at a minimum, simply as a referential point in Pitch space from which subsequent Texture transpositions are referenced.