We bought these cards from ThinkFun via Amazon a while back. They have musical notes on them and a card code in the corner. They can be flipped and rotated.

The idea is to arrange them into phrases and / or compositions. There was a website you could type the codes into, press a button and hear your composition played back from composed prerecorded hi fidelity orchestral and percussion recordings. Really cool. My kid loved it. You could also download/email PDFs and MP3s of your compositions.

Sadly they got shut down due to California's equivalent of GDPR.

• https://www.thinkfun.com/compose-yourself-apology/

So some years later, with kid number 2 now getting interested in music and kid number 1 interested in music and programming, kid number 1 suggests we could just build it again. So here we are...

I don't have the wonderful orchestral / percussion samples that match the cards but web browsers have a basic synthesizer in their audio APIs and they can play samples loaded from a server and I have a piano so maybe we can come close to the original. We'll see.

There are 60 transparent cards. 30 different. 2 of each. 4 digit code represents each card. e.g. 0021 Rotate 0021 180 degrees to get 0022 Flip 0021 along the beats 2/3 axis to get 0023 Flip 0021 along the B4 axis to get 0024 So there are 30x4 different 4/4 bar phrases. Featuring combinations of only minim, crochet, quaver durations.

Rotation operation is a composition of:

• Flip along beats 2/3 axis
• Flip along B5 axis

• 0011 - 0091 in incremements of 10 e.g. 0011, 0021, 0031, ... 0091
• 0101 - 0191 in increments of 10 e.g. 0101, 0121, 0131, ... 0191
• 0201 - 0291 in increments of 10 e.g. 0201, 0221, 0231, ... 0291
• 0301 alone

Again, there are 2 of each card and each card has 4 codes e.g.

• 0231
• 0232
• 0233
• 0234

1. Create card code to music data structure
2. Rotate and flip the cards as described above to build out all variations. This may benefit from a music library that understands a bit of music theory.
3. Play a card - web midi
4. Type in a card code to play a card
5. Type in a list of cards to play several in a row, smoothly
6. Render a card
7. Type in a card code to render a card
8. Type in a list of cards to render several cards

• Name a project - Save, List, Load, Rename, Delete
• Drag cards around, buttons to flip and rotate
• Render all the cards in a pallete/drawer, drag and drop into composition
• Restore original Compose Yourself functionality: ** Email a PDF to yourself - requires account creation and email confirmation etc. ** Download a fully stitched together mp3 from samples of each card. *** Can I get the wonderful orchestral and marimba samples?

I need a native JS DS that I can use to play midi from and render notes from.

• Will start with vexflow's easyscore
• I only need treble clef notes without accidentals and very limited durations:
  • Minim - /h
  • Crochet - /q
  • Quaver - /8
• It uses midi notation so C4 is middle C