com.soundhelix.component.harmonyengine.impl

Class PatternHarmonyEngine

java.lang.Object

com.soundhelix.component.harmonyengine.impl.AbstractHarmonyEngine

com.soundhelix.component.harmonyengine.impl.PatternHarmonyEngine

All Implemented Interfaces:

Component, HarmonyEngine, RandomSeedable, XMLConfigurable

public class PatternHarmonyEngine
extends AbstractHarmonyEngine

Implements a flexible HarmonyEngine based on user-specified patterns. The patterns consist of chord patterns and random table patterns. One of the given chord patterns is chosen at random. A chord pattern consists of comma-separated combinations of chords and lengths in beats (separated by a slash). A chord is either a simple chord name ("C" for C major, "Am" for A minor, etc.), a random table number (starting from 0), a random table number (starting from 0) with a negative backreference (e.g., "0!0") to an already generated chord at an earlier position or it can be a positive backreference to an already generated chord at an earlier position ("$0" for first chord, "$1" for second chord, etc.). If a random table number is given, a chord is randomly chosen from that table. Chord random tables a comma-separated lists of chord names (e.g., "Am,G,F,Em,Dm"), they are numbered starting from 0. For example, the chord pattern "Am/4,0/4,0!1/4,$1/4" means "A minor for 4 beats, a random chord from random table 0 for 4 beats, a random chord from random table 0 but not the same as the one from position 1 for 4 beats and the second chord again for 4 beats " and could result in the chord sequence "Am/4,F/4,G/4,F/4" (given suitable random tables). Normally, each chord pattern is an individual chord section. A pattern can be split into two or more chord sections by using "+" signs directly before a chord/length combination (e.g., "Am/4,F/4,G/4,C/4,+Am/4,F/4,G/4,Em/4").

Author:

Thomas Schuerger (thomas@schuerger.com)

Field Summary

Fields inherited from class com.soundhelix.component.harmonyengine.impl.AbstractHarmonyEngine

logger, randomSeed

Constructor Summary

Constructors

Constructor and Description
PatternHarmonyEngine() Constructor.

Method Summary

Methods

Modifier and Type	Method and Description
void	configure(SongContext songContext, Node node) Configures the instance using the specified XML node.
Harmony	render(SongContext songContext) Renders a harmony.
void	setChordPatterns(com.soundhelix.component.harmonyengine.impl.PatternHarmonyEngine.ChordPattern[] chordPatterns)
void	setChordRandomTables(String[][] chordRandomTables)
void	setMinimizeChordDistance(boolean isMinimizeChordDistance)

Methods inherited from class com.soundhelix.component.harmonyengine.impl.AbstractHarmonyEngine

getRandomSeed, setRandomSeed

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Constructor Detail

PatternHarmonyEngine

public PatternHarmonyEngine()

Constructor.

Method Detail

render

public Harmony render(SongContext songContext)

Description copied from interface: HarmonyEngine

Renders a harmony.

Parameters:

songContext - the song context

Returns:

the harmony

setChordPatterns

public void setChordPatterns(com.soundhelix.component.harmonyengine.impl.PatternHarmonyEngine.ChordPattern[] chordPatterns)

setChordRandomTables

public void setChordRandomTables(String[][] chordRandomTables)

configure

public void configure(SongContext songContext,
             Node node)
               throws XPathException

Description copied from interface: XMLConfigurable

Configures the instance using the specified XML node. The method should read all supported configuration tags and should call the corresponding setter methods of the class. All settings of the class that are settable using XML should also be settable by using public methods (for example, if the beats per minute are settable using an XML tag, then the class should also provide a public method setBPM(), which does the same). XML configuration can also be a recursive process, if XML settings contain nodes that require XML configuration themselves, but this is up to the implementation of this method. The method should (but need not) use XPath to access the node's tags. Only the node and its descendant nodes may be used for configuration.

Parameters:

songContext - the song context

node - the parent XML node of the configuration tags

Throws:

XPathException - in case of an XPath problem

setMinimizeChordDistance

public void setMinimizeChordDistance(boolean isMinimizeChordDistance)