Custom Query (25 matches)

I propose we generalize the animate, simulate, and play actions by providing variants allowing IO actions for world stepping and rendering.

The reasoning here is: 1) World-stepping should be permitted to be IO because there might be outside influences on the world state (ex: a networked game). 2) Rendering the world should be permitted to be IO because there might be outside information needed (texture loading, map tile retrieving, etc).

This would be particularly useful for work like gloss-osm, that allows immediate rendering by presenting missing tiles with a default until the download is complete.

With this program:

import Graphics.Gloss
main    
= animate (InWindow "Foo" (800,800) (0,0)) black 
$ \t -> pictures 
       [ color white $ ThickArc (5 * t+ 0.01) (10 * t+ 0.1) 200 100
       , color red   $ ThickArc (5 * t+ 0.01) (10 * t+ 0.1) 250 10
       , color red   $ ThickArc (5 * t+ 0.01) (10 * t+ 0.1) 150 10 ]

The arc ends aren't at the right angle, depending on the value for the total arc length. I expect this is an interaction between the number of draw steps and the total length.

I tried this in a typical Gnome environment, but the window never refreshed and X hogged 100% of the CPU.

{-# LANGUAGE CPP #-}
import Graphics.Gloss.Game
import Graphics.Gloss
import Data.Maybe (maybe)
import Debug.Trace

main = do
      let state = St Nothing []
      gameInWindow "Test Game" (1400,1050) (0,0) white 100 state makePicture handleEvent stepWorld

data State = St (Maybe Path) [Picture]
type Segment = ((Float, Float), (Float, Float))

makePicture :: State -> Picture
makePicture (St m xs) = Pictures (maybe xs (\x -> Line x : xs) m)

handleEvent :: Event -> State -> State
handleEvent e st = trace (show e) (handleE e st)

handleE (EventMotion (x,y)) st@(St (Just ps) ss) = St (Just ((x-418,516 - y):ps)) ss -- Here is the offset for a 1/2 window on xmonad
handleE (EventKey (MouseButton LeftButton) Down _ pt@(x,y)) st@(St Nothing ss) = St (Just [pt]) (Translate x y (Text "Down") : ss)
handleE (EventKey (MouseButton LeftButton) Up _ pt@(x,y)) st@(St (Just ps) ss) = St Nothing (Translate x y (Text "up") : Line (pt:ps) : ss)
handleE _ st = st

stepWorld :: Float -> State -> State
stepWorld _ = id