Adam Fox's Final Project: Guitar Hero Interface
For my final project, I used ChucK to build an two different instruments that can be played with a Guitar Hero controller.
Rhythm Guitar Hero
The first instrument uses the Karplus Strong algorithm to simulate a six-string acoustic guitar that strums chords. The chords are preprogrammed, such that each voicing is consistent with that of a real acoustic guitar. Some of the methods implemented for the class RhythmGuitarHero are:
- .capo(int, READ/WRITE) ... tunes the guitar up by half-steps, simulating a capo
- .setStrumSpeed(float, READ/WRITE) ... sets the strum speed (0 is instantaneous, 1 is a slow arpeggio)
- .startPlaying() ... puts the guitar in interactive mode, allowing live performance
How to Play the Rhythm Guitar
Once the .startPlaying method is accessed, the interactive mode is turned on.
- One can perform a "strum" with button 8. It is possible to strum in either direction, up or down.
- Holding down buttons 1-4 correspond to six different chords in one key; the default key is C. The guitar does not support diminished triads or diminished 7th chords.
- Simultaneously holding the A button will alter the chord. (The "most common alteration" is used)
- Button 6 shifts the key up one half step. Button 7 shifts the key down one half step.
Chord Fingerings and Alterations
- I Chord: Button 1. Alteration: Dominant 7th
- ii Chord: Buttons 1, 2. Alteration: Major 3rd
- iii Chord: Buttons 1, 2, 3. Alteration: Major 3rd
- IV Chord: Buttons 1, 2, 3, 4. Alteration: Minor 3rd
- V Chord: Buttons 2, 3, 4. Alteration: Dominant 7th
- vi Chord: Buttons 3, 4. Alteration: Major 3rd
The rhythm guitar does not support the diminished vii chord.
The second class LeadGuitarHero is designed to give the freedom to play some riffs and "hammer" solos. The sound is implemented with an enveloped SndBuf (guitar sound is provided here). Right now, LeadGuitarHero supports solos on the blues scale, although it would be simple enough to integrate a method .setNotes in order to have the guitar play any such scale.
- .gain(float, READ/WRITE) ... this sets the gain of the guitar (default is 1.0)
Playing the Lead Guitar
- Button 8 triggers the enveloping (turns the guitar on and off)
- Similar to the rhythm guitar, the buttons 1-4 correspond to notes on the blues scale.
- First note: 1
- Second note: 1, 2
- Third note: 1, 2, 3
- Fourth note: 1, 2, 3, 4
- Fifth note: 2, 3, 4
- Sixth note: 3, 4
- Seventh note: 4
- The button 6 increases the key by one half step. Similarly, the button 7 decreases the key.
- The A button is not functional in this class.