oscpacking-0.1.0.0: Boundary.hs

{--
This file is part of the OscPacking library.
Copyright 2016 Christopher Howard.

    OscPacking is free software: you can redistribute it and/or modify
    it under the terms of the GNU General Public License as published by
    the Free Software Foundation, either version 3 of the License, or
    (at your option) any later version.

    OscPacking is distributed in the hope that it will be useful,
    but WITHOUT ANY WARRANTY; without even the implied warranty of
    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
    GNU General Public License for more details.

    You should have received a copy of the GNU General Public License
    along with OscPacking.  If not, see <http://www.gnu.org/licenses/>.
--}

module Boundary where

import Geometry

type Boundary = Point -> Maybe Float

circleB :: Point -> Float -> Boundary
circleB originP r testP =
  if d > r then Nothing else Just (r - d) where d = euclidean originP testP

rectB :: Point -> Float -> Float -> Boundary
rectB (bLX, bLY) width height (tPX, tPY) =
  if or [tPX < bLX,
         tPX > bLX + width,
         tPY < bLY,
         tPY > bLY + height]
  then Nothing
  else Just $ foldr min (1/0)
       [tPX - bLX,
        bLX + width - tPX,
        tPY - bLY,
        bLY + height - tPY]