{-# OPTIONS_GHC -fno-warn-warnings-deprecations #-} {-# LANGUAGE ExistentialQuantification, MultiParamTypeClasses, FlexibleInstances, StandaloneDeriving #-} ----------------------------------------------------------------------------------------- -- | -- Module : FRP.Yampa.Point2 -- Copyright : (c) Antony Courtney and Henrik Nilsson, Yale University, 2003 -- License : BSD-style (see the LICENSE file in the distribution) -- -- Maintainer : nilsson@cs.yale.edu -- Stability : provisional -- Portability : non-portable (GHC extensions) -- -- 2D point abstraction (R^2). -- ----------------------------------------------------------------------------------------- module FRP.Yampa.Point2 ( Point2(..), -- Non-abstract, instance of AffineSpace point2X, -- :: RealFloat a => Point2 a -> a point2Y -- :: RealFloat a => Point2 a -> a ) where import FRP.Yampa.VectorSpace () import FRP.Yampa.AffineSpace import FRP.Yampa.Vector2 import FRP.Yampa.Forceable -- * 2D point, constructors and selectors -- | 2D point. data Point2 a = RealFloat a => Point2 !a !a deriving instance Eq a => Eq (Point2 a) deriving instance Show a => Show (Point2 a) -- | X coordinate of a 2D point. point2X :: RealFloat a => Point2 a -> a point2X (Point2 x _) = x -- | Y coordinate of a 2D point. point2Y :: RealFloat a => Point2 a -> a point2Y (Point2 _ y) = y -- * Affine space instance instance RealFloat a => AffineSpace (Point2 a) (Vector2 a) a where origin = Point2 0 0 (Point2 x y) .+^ v = Point2 (x + vector2X v) (y + vector2Y v) (Point2 x y) .-^ v = Point2 (x - vector2X v) (y - vector2Y v) (Point2 x1 y1) .-. (Point2 x2 y2) = vector2 (x1 - x2) (y1 - y2) -- * Forceable instance instance RealFloat a => Forceable (Point2 a) where force = id