Scripts

User can redefine of shape’s default behaviors including rendering, outlining and defining connection points. The followings are supported script types of a shape:

• render
• outline
• connection-points

render

The script bound to render should code how to draw the shape. The below code is to draw a triagle inside a box.

render (triangle)

(do
  (def! l (. shape :left))
  (def! r (. shape :right))
  (def! t (. shape :top))
  (def! b (. shape :bottom))
  (def! xc (/ (+ l r) 2))
  (. canvas :polygon [[xc t] [r b] [l b]])
  (. shape :renderText canvas))

You can use the shape’s default rendering behavor. The below code is draw the cross mark over the rectangle’s default rendering.

render (cross box)

(do
  (def! l (. shape :left))
  (def! r (. shape :right))
  (def! t (. shape :top))
  (def! b (. shape :bottom))
  (. shape :renderDefault canvas)
  (. canvas :line l t r b)
  (. canvas :line r t l b))

outline

The script bound to outline should express a vector of points that constitutes the outline of the shape. The below is to define the outline of a triangle.

outline (triangle)

(do
  (def! l (. shape :left))
  (def! r (. shape :right))
  (def! t (. shape :top))
  (def! b (. shape :bottom))
  (def! xc (/ (+ l r) 2))
  [[xc t] [r b] [l b] [xc t]])

connection-points

The script bound to connection-points should express a vector of points that constitutes the connection points of the shape. The below code is to define three connection points on each vertex of a triangle.

connection-points (triangle)

(do
  (def! l (. shape :left))
  (def! r (. shape :right))
  (def! t (. shape :top))
  (def! b (. shape :bottom))
  (def! xc (/ (+ l r) 2))
  [[xc t] [r b] [l b]])