Informationswissenschaft Python Projekt: Music Programming Language
Example songs and scripts can be found in the /songs/ folder.
python3 pygame (for audio output)
IW_MPL is a first approach to a music (or audio) programming language (Wikipedia https://en.wikipedia.org/wiki/List_of_audio_programming_languages). It is a very simple concept and only includes some basic functionality, but it is fully usable for creating and playing easy songs.
Unlike ChucK (http://chuck.cs.princeton.edu/), IW_MPL does not contain any programming logic or conditional expressions, like if or while. Basically, IW_MPL is just a small interpreted language that gets converted into notes.
A valid IW_MPL script consists of (at least) three parts:
- An instrument
- Some notes
- A Song
Use the Instrument keyword to create a new instrument block.
IW_MPL expects to find an identifier after the Instrument keyword, like Instrument Piano.
To specify your instrument, you need to encapsulate it with a block statement [ ] (everything between two square brackets is considered a block).
Example:
Instrument Piano [
; your instrument details
]
Each instrument must at least provide one list of notes, identified by the Notes keyword, also encapsulated by a block.
You also need to give your notes an identifier.
Example:
Instrument Piano [
Notes MyNotes [
; your notes here
]
]
Inside a notes block, you are free to write note names. Currently, IW_MPL only supports the following notes:
c1 c2 c3 c4 c5 d1 d2 d3 d4 e1 e2 e3 d4 f1 f2 f3 f4 g1 g2 g3 g4 a1 a2 a3 a4 b1 b2 b3 b4
and rest . (a dot is basically just a skip-the-current-bar note)
Example:
Instrument Piano [
Notes MyNotes [
c3 d3 e3 f3 g3 . g3 . a3 a3 a3 a3 g3
]
]
To create a song, you have to arrange a sequence of music pieces together. This can be done with the Song keyword:
Song Example [
Piano.Intro + Harp.Intro, Harp.Intro, Piano.Chorus
]
where a plus sign (+) plays multiple pieces in parallel, while a comma (,) starts a new sequence.
You refer to a specific music piece by writing the instrument's name and the name of the notelist, concatenated by a dot (.).
Note: You can only play two pieces of different instruments at the same time, so you can't write Piano.Intro + Piano.Outro, for example!
Finally, use the Play keyword, to play a specific song.
Example: Play Example where example is the name of the song.
Variable names MUST start with a CAPITAL letter!
Some examples of valid variable names in IW_MPL:
MyVariable
NEWTYPE
Invalid variable names are note identifiers, keywords and variables not starting with a capital letter and/or containing
other characters than a-z A-Z 0-9 _
Examples of invalid variable names:
myVariable
c3
It is also forbidden to use keywords as the beginning of a variable name, like:
Instrument2
You can assign any numeric values to a variable:
MyVar: 5
You can then assign your variable to another variable:
MyOtherVar: MyVar
MyOtherVar will contain the value of MyVar, so 5.
Currently, IW_MPL only supports numeric values for its variables.
There are some constant values already assigned:
PIANO = 1
BASS = 2
SYNTHESIZER = 3
These constants can be used as a variable for your instrument's IType variable:
IType: PIANO
assigns the piano instrument to your current instrument block.
However, you can modify each of your variables by prepending the const keyword, like:
const MyVar: 3
A constant can only be assigned once and never changed again.
You can write comments by using a semicolon.
Note: The comment reaches until the next line break, so any code after a comment will also be ignored!
Example comment:
BPM: 80 ;This is my example comment on this variable assignment