packages feed

brillo-examples-1.13.3: picture/Eden/Cell.hs

module Cell where

import Brillo


data Cell
  = Cell
      Point -- centre
      Float -- radius
      Int
  deriving (Show)


-- Produce a new cell of a certain relative radius at a certain angle.
--      The factor argument is in the range [0..1] so spawned cells are
--      smaller than their parent.
-- The check whether it fits in the community is elsewhere.
offspring :: Cell -> Float -> Float -> Cell
offspring (Cell (x, y) r gen) alpha factor =
  Cell
    (x + (childR + r) * cos alpha, y + (childR + r) * sin alpha)
    childR
    (gen + 1)
  where
    childR = factor * r


-- Do two cells overlap?
-- Used to decide if newly spawned cells can join the community.
overlap :: Cell -> Cell -> Bool
overlap (Cell (x1, y1) r1 _) (Cell (x2, y2) r2 _) =
  centreDist < (r1 + r2) * 0.999
  where
    centreDist = sqrt (xdiff * xdiff + ydiff * ydiff)
    xdiff = x1 - x2
    ydiff = y1 - y2


render :: Cell -> Picture
render (Cell (x, y) r gen) =
  let z = fromIntegral gen * 0.1
      color' = makeColor 0.0 z 0.5 1.0
  in  Color color' $ Translate x y $ Circle r