an implementation on De Casteljau's algorithm, capable of sending MIDI (trigger), OSC to target client/server eg.SuperCollider (OSC only works in repl mode), NOTE: xen is backend-agnostic, Intentionally used for live performance. thus, no built-in audio engine is implemented.

video taken by Tentacle Workshop Bkk

Run

git clone https://github.com/karnpapon/xen.git
cd xen
npm install
npm run start

# in order to send OSC
# open new terminal tab.
cd bridge  
npm install
node index.js

Keybinding

• play/pause: spacebar
• add new point: cmd + left click
• add point group: Shift + n = spawn new point group.
• remove point: right click at target point (make sure group is selected).
• trigger first/last line t, since cubic bezier calculated by four points. by nature the distance between point is basically a straight line. thus moving point cannot avoid colliding with first line(start) and last line(end). use this option to avoid trigger first/last line.
• switch between point group: tab, selected group will be highlighted in BLUE color rgb(0,0,255)
• toggle control-line: c = only current selected group, Shift + C = toggle all group.
• toggle L-Point: l = toggle even recursived points (collision in RED), Shift + L = toggle all points.
• toggle R-point: r = toggle odd recursive points (collision in BLUE), Shift + R = toggle all points.

File/Folder

• /src: main xen's sourcecode.
• /tool: for test sending msg(osc).
• /bridge: for receiving msg(osc) from browser and forward to target server.

IO

• midi.
• osc: Sends OSC message, NOTE run node bridge/index.js first. in order to send OSC out to host.

Resources

• https://pomax.github.io/bezierinfo/#decasteljau
• https://www.khanacademy.org/computing/pixar/animate/parametric-curves/a/equations-from-de-casteljaus-algorithm
• https://www.youtube.com/watch?v=aVwxzDHniEw
• https://webmidijs.org/docs/getting-started/basics/