fwgl-0.1.0.0: FWGL/Utils.hs

module FWGL.Utils (
        screenScale
) where

import FRP.Yampa
import FWGL.Input
import FWGL.Graphics.Custom

-- | Generate a view matrix that transforms the pixel coordinates in OpenGL
-- coordinates.
screenScale :: SF Input M3
screenScale = size >>^ \(x, y) -> scaleMat3 (V2 (1 / fromIntegral x)
                                                (1 / fromIntegral y))

-- | Like 'dynamic', but instead of comparing the two objects it checks the
-- event with the new object.
dynamicE :: Object g i -- ^ Initial 'Object'.
         -> SF (Event (Object g i)) (Object g i)
dynamicE = dynamicG $ flip const

-- | Automatically deallocate the previous mesh from the GPU when it changes.
dynamic :: SF (Object g i) (Object g i)
dynamic = undefined
{-
dynamic =
        dynamicG (\ o n -> if objectGeometry o == objectGeometry n
                                then Event n
                                else NoEvent
        ) nothing
-}

dynamicG :: (Object g i -> a -> Event (Object g i)) -> (Object g i) -> SF a (Object g i)
dynamicG = undefined
{-
dynamicG f i = flip sscan i $ \ oldObj inp ->
                case f oldObj inp of
                        Event (SolidObject (Solid (StaticGeom newG) mat tex)) ->
                                SolidObject (
                                        Solid (DynamicGeom (objectGeometry oldObj)
                                                           newG)
                                              mat
                                              tex
                                )
                        NoEvent -> case oldObj of
                                        SolidObject (
                                                Solid (DynamicGeom _ new) mat t
                                                ) -> SolidObject (
                                                        Solid (StaticGeom new)
                                                              mat
                                                              t
                                                        )
                                        _ -> oldObj
                        _ -> error "dynamicG: not a Geometry."
-}