JavaFX impressive game (Crayon Physics)

Functional programming, expression binding, and graphics:

var p = Polygon { points: bind [ firstPick.x, firstPick.y, curPick.x, curPick.y, if(curPick.y > firstPick.y) [firstPick.x, curPick.y] else [curPick.x, firstPick.y] ] }