Mellow D Language Reference

Overview

1. Base Elements
1. Notes
2. Articulation
3. Beat
4. Dynamics
5. Percussion
2. Complex Elements
1. Chords
2. Melodies
3. Rhythms
4. Phrases
3. Top Level Structures
1. Variables
2. Blocks
3. Block Options

Base Elements

Notes

A note is the base element in Mellow D. It is the building block of sounds. Notes are a note char (lowercase a to g) followed by a flat ($) or sharp (#) token followed by an octave shift (+ or - followed by a number 0 to 9). The * character defines a rest.

Ex:

Articulation

Articulation affects how a note or chord is performed. Articulation can be applied to a chord or a note as long as the note is appearing in a melody. For example a$. would preform an a flat with an abrupt stop and a shorter duration (staccato). (c, e, g)~ would perform a C chord playing each note quickly in succession creating a roll. See the Articulation class for more detail on each articulation.

Mellow D supports the following articulation mappings:

Beat

Beats describe the duration of a sound. Mellow D supports w, h, q, e and s to represent the musical whole, half, quarter, eight and sixteenth note respectively. A beats duration can be extended just like a musical · using 0 or more . following the beat token. Each additional . adds half of the previous added value. See the Beat class for more detail on how the dot functions. Beats are the building blocks of Rhythms.

Dynamics

Dynamics affect the volume of the sound preformed. Mellow D supports the following dynamic tokens in increasing order of volume: pppp, ppp, pp, p, mp, mf, f, ff, fff, ffff. By default the dynamic is mf. Dynamic tokens appear anywhere a phrase can appear and they set the dynamic for phrases following it in the block it appears in. The dynamic can be set as often as desired and functions the same way it does if written in a piece of sheet music.

Crescendo (<<) and decrescendo (>>) tokens can appear directly following a dynamic token resulting in the volume gradually changing until it reaches the next dynamic. For example ff >> phrases mf would gradually drop the volume from double forte to mezzoforte over the phrases.

Percussion

Percussion can be considered a mode in Mellow D. In percussion mode there are an additional set of identifiers for describing percussion sounds. They appear anywhere a note normally would. The full list of supported sounds can be found in GeneralMidiPercussion. On a percussion channel playing a MIDI note plays its percussion mapping’s sound. This means that the percussion sounds can be represented as pitches and can actually be preformed as percussion or as their respective pitch. It is the developers responsibility to make sure that percussion sounds are played in percussion blocks as the compiler directly resolves them to a pitch and has no way of realizing if it was defined as percussion or not. See block options for how to put a block in percussion mode and the variables section for how to define a variable in percussion mode.

Complex Elements

Mellow D sounds are created from 3 complex elements components. Chords, Melodies and Rhythms. All 3 of these types can be defined as a variable and variable values can be concatenated with new element definitions by using the variable identifier in the definition. For example if myChord is defined as a Chord, a new chord containing all the notes in myChord can be declared as (myChord, c, e, g). A phrase is the product of playing a melody or chord over a rhythm.

Chords

A chord is a collection of notes that are performed concurrently. In the Mellow D source a chord is defined as an opening ( followed by a note or multiple notes seperated by a , with a closing ) at the end. Ex: (c, e, g) (c#, f, g#, c#+1)

There are many frequently used chords and to avoid requiring these definitions in each source a standard chord set is virtually declared in the head of the source. This means that the developer is free to use and if desired, redefine them. All of the predefined chords match the pattern [A-G] ( 's' | 'b' )? ( 'u' | 'd' [0-9]+ )? ( [a-z0-9]+ )? which can be found in the Chord class. The chord names begin with a capital letter from A to G followed by an optional s or b to make the chord sharp or flat respectively. This defines the root note of the chord which can be shifted up (u) or down (d) a number ([0-9]+) of octaves. The root description is then transformed into a chord based on the last identifier.

These chord creation identifiers include:

See the Chord class for more information about the intervals in each chord.

Ex: C Ds Ebu3 Cm Ab7 Bu1dom7

Chord indexing can be used to pull a note out of a chord. This only works on chord variables as if the chord is being defined in place there is no need to index the chord, just use the exact pitch at that position. To index a chord follow a chord variable name with a : and a number ([0-9]+). The number is the index of the pitch to reference. Indexing starts at 0.

Ex: if myChord -> (c, e, g) is declared, myChord:0 will resolve to c, myChord:2 will resolve to g.

Melodies

A melody is a sequence of notes or chords that are preformed sequentially. Each element in a melody can be articulated. A melody is a declared in a Mellow D source as a list of 1 or more melody parameters separated by ,, an opening [ and a closing ].

Ex: [a, b$, c#] [a!, (c, e, g)~, e-1.] [C:0, C:1, C:2] [a, *, b, *]

Rhythms

A rhythm is a collection of beats that can be understood as how the song would sound if the only sound was a tapping sound. A rhythm is combined with a melody or chord to create a phrase. In a Mellow D source it is declared as a , separated list of beats with an opening < and closing >.

Ex: <w, h, q, e, s> <q., q>

Slurring notes in Mellow D is the equivalent of applying a tenuto (_) articulation to each note matched with the slurred beat. It results in a nice gliding sound between sounds. In a rhythm declaration slurred notes are wrapped in ( and ).

Ex: <q, (q, q, q)> the last 3 quarter notes q are slurred.

Tuplets (most commonly a triplet) alter the duration of a beat in a negative way. See the Beat class for an in-depth explanation of how beat durations inside a tuplet are calculated. Tuplets can be declared as simply a number ([0-9]+) before a beat or a number ([0-9]+) : a number ([0-9]+). If the (:[0-9]+) are excluded it is implied to be 1 less than the given number. If the first number is named num and the second div the tuplet preforms num of the following beat in the time normally taken to preform div of the following beat.

For example a quarter note triplet (3q) would play 3 quarter notes in the time normally taken to play 2. A 5:3q tuplet would preform 5 quarter notes in the time normally taken to preform 3.

Tuplets can be slurred as well by wrapping the tuplet beat with ( and ).

Ex: <q, q, 5e> <3(q), h> <7:4e, q, 3(e)>are all 4 beats long

Phrases

A phrase is a structure that can be played. It, like the other complex elements can be declared as a variable. A phrase is constructed as the product of a melody or chord with a rhythm with the * operator. A phrase is a sequence of playable sounds such that each sound has a duration. The length of this sequence is determined by the longest of rhythm or pitch component by repeating the shorter element until the length matches the length of the longer element.

For example:

• [a, b, c]*<e> will preform 3 sounds each for an eight note
• [a, b]*<e, e, q> will preform 3 sounds: an eight note a, an eight note a and a quarter note a
• [a, b, c]*<3q, h> will preform 4 sounds: the a, b, c triplet followed by a half note a.
• Cminmaj7*<q, e, e, q> will preform 4 sounds: the Cminmaj7 chord for a quarter, eight, eight, quarter note.

Top Level Structures

At the top level of the Mellow D source only 2 structures are accepted, variable declarations and blocks. The majority of the source is taken up with blocks as these are where the the song is declared.

Variables

Variables can be very beneficial in reducing the amount of repetitive sound or rhythm definitions. A variable is a key value mapping with each variable having a dynamic type. The type is evaluated at the time the value is needed and may change anytime. The source is evaluated from the top down and so the value of a variable is the most recent declaration above where the value is requested. Variable definitions look like identifier -> value where value can be a chord, melody, rhythm or a phrase. A variable declaration with a * following the -> results in the value being compiled as if inside a percussion block, identifier ->* value.

Variables declared will be shifted to the appropriate octave when their value is required. A variable reference can be used anywhere that the value could be used. An identifier that points to a chord can be used anywhere a chord could be declared.

Blocks

Blocks are the core structure of Mellow D. A block can be thought of as a thread for those with a programming background. Each block is a stream of sounds flowing to the MIDI synthesiser. Every block is declared with a unique name. If a block with the same name as an existing block the contents are appended to the original. All blocks start at the beginning of the song and their location in the source does not affect when the contents are preformed, only the order of the fragments matters.

A block starts with an identifier followed by optional block options followed by an opening { and a closing }. Everything between the { and } is the contents. The contents can be dynamic declarations or phrases. For example the left and right hand of a piano piece with each hand playing concurrently:

leftHand[octave -> 3] {
ff [c, e, g, c+1]*<q>
}

rightHand[octave -> 5] {
f << [Cmaj, Gm, Em]*<q> ff
}

leftHand {
f >> G*<e, e, h.> p
}

Block Options

Block options are a set of knobs the developer can turn to better control the block. There are 2 types of block options: property style options and flag options.

Property options look like a variable declaration, identifier -> value with the value being either an identifier or a number. A list of accepted property options are the following:

Flag options are used for boolean options. They can be thought of as a switch. If the option is given as identifier it turns the option on. If given as -identifier it turns the option off. A list of accepted flag options are the following:

Block options appear after a block name and, other than loop and repeat, carry throughout each fragment. The options start with an opening [, end with a closing ], and are filled with a list of property or flag options separated with a ,.

For example: [percussion, octave -> 5, sharechannel -> myOtherBlock] or [instrument -> chimes, -drums]