Noteskins

Noteskins are decorative images that StepMania uses to display notes (typically arrows, but can be other imagery, like bars). Noteskins are themeable in the sense that they can have commands applied to certain parts, and are Sprites themselves!

Noteskin Types
Noteskins are similar to Theme graphics in the sense that they both follow the Class Subclass naming convention ( for example), however noteskins are much more diverse and have many varied names and items. Usually the Class is the button to represent, and the several subclasses are used to represent what the note is.

Any one class ("Down", "DownLeft", "Scratch", "Key5" to name a few ) can contain many many types to ensure each one looks different and recognizable during gameplay. There are a bevy of them to watch for. The following list of subclasses assumes "Down" is the represented button:

3.9 Noteskin Classes
In 3.9, you are alloted the following classes, with addition to a nice modularity bonus: All normal taps ( Note & Addition ) can diversify their imagery for each note's musical placing ( 4th, 8th, 12ths.. ), further emphasizing creativity ( or allowing emulation )

The above also comply for the "Roll" note type ( A segment in which you must continually press the corresponding button to keep it alive, so you can score it ). For reference they are completely alike to Holds:
 * Down Roll Head Inactive
 * Down Roll Head Active
 * Down Roll TopCap Inactive
 * Down Roll TopCap Active
 * Down Roll BottomCap Inactive
 * Down Roll BottomCap Active
 * Down Roll Tail Inactive
 * Down Roll Tail Active
 * Down Roll Body Inactive
 * Down Roll Body Active
 * Down Roll Explosion
 * Unlike Down Hold Explosion, This image will become prominent every time the player successfully presses the corresponding button

SM-SSC Noteskin Changes
In later StepMania builds (past 3.95), Note-based diversity (4th, 8th, 12ths..) were removed for an unknown reason. However, in its place, a new way to control noteskins was added: Noteskin.lua.

Replacements
Down Tap Hidden → Down Tap Fake

Noteskin.lua
Noteskin.lua contains several blocks of information allowing the editor to display or modify certain button imagery. The noteskin table (known as "ret" for return, as in what to tell StepMania) has a few available categories for the user to create or modify images, explained below:

RedirTable allows you to remap a certain Button to another, for example, "Down" to "Left".

Rotate allows you to control which Button should be rotated in how many degrees if you allow them, useful if you are remapping one button to another and want to avoid confusion:

PartsToRotate allows you to control which part of a noteskin should actually be rotated:

Blank allows you control which part of a noteskin simply doesn't show up:

SM4 started the remap tradition, redirecting all directions to Down instead of Up Down Left & Right to conserve having to remake graphics & being able to deliver a noteskin of a smaller file size