JuggleJS

A JavaScript site-swap juggling patterns interpreter and simulator.

Definitions

• Prop - object used for juggling
• Site-swaps - popular notation for recording patterns
• Pattern - specific sequence of prop manipulations - throws, stalls, bounces, etc
• Beat/Tick - the start of each manipulation defines a beat (0 being the null/empty manipulation)

Site-swaps

Initially hold the X and Z ball in your right hand and the Y ball in your left. Let's execute the 441 pattern. Props - X, Y, Z (3 balls) Alternating "hands" L - left hand, R - right hand
RLRLRLRLR XYZZXYYXZ Let's break it down. First we throw the X ball from our right, it will fall on the 4th beat. The next beat is from the left hand. LRLRLRLR YZ-X Throw the Y ball from the left hand, again it will fall on the 4th beat. Right hand next. RLRLRLRL Z-XY Throw the ball across, it will fall on the next beat (in the other hand) LRLRLRLR ZXY You can now start the pattern again; this time left hand first, or do a different pattern altogether.

Example Patterns

531, 3, 441, 501, 40, 423, [53]01, [54]21

Verification

sum of numbers / count must be integer and constitutes the number of balls

Information Sources

• starting hand - juggler
• number of balls - pattern

Sample AST

[{
    tick: 0,
    prop: 0,
    origin: 0,
    siteswap: 5
},
{
    tick: 1,
    prop: 1,
    origin: 1,
    siteswap: 3
},
{
    tick: 2,
    prop: 2,
    origin: 0,
    siteswap: 1
}]

Sample Prop State Transitions:

transitionAsString = "XYZ >4> YZ_X >4> Z_XY >1> ZXY >4> XY_Z >4> Y_ZX >1> YZX >5> ZX__Y >3> X_ZY >1> XZY >5> ZY__X >3> Y_ZX >1> YZX"

To Do

Use WebGL (Three.js) to animate the AST