README

This package provides a simple wrapper for the gloss library, or rather the function Graphics.Gloss.play, enabling you to write gloss applications as signal functions. An example “gears” program, which you can run as cabal run rhine-gloss-gears or stack build && stack exec rhine-gloss-gears, now becomes as simple as:

module README where

import FRP.Rhine.Gloss


-- | Calculate a gear wheel rotated by a certain angle.
gears :: Float -> Picture
gears angle = color green $ pictures
  $ circleSolid 60
  : map (rotate angle) [ rotate (45 * n) $ rectangleSolid 20 150 | n <- [0..3] ]

-- | Rotate the gear with a constant angular velocity.
mainClSF :: GlossClSF
mainClSF = timeInfoOf sinceInit >>> arr (* 50) >>> arr gears

main :: IO ()
main = flowGloss defaultSettings mainClSF

Installation

Since gloss is based on OpenGL, you will need to install the same dependencies as for that. Typically, this are the GL, GLU and GLUT libraries. (On Debian-like systems, sudo apt-get install libgl1-mesa-dev libglu1-mesa-dev freeglut3-dev should suffice.)

When building with stack, it is assumed that you have nix-shell installed, which will automatically get these dependencies for you.