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{-# LANGUAGE CPP #-}
{-# LANGUAGE OverloadedStrings #-}
{-# LANGUAGE LambdaCase #-}
{-# LANGUAGE MultiWayIf #-}
{-# LANGUAGE PatternSynonyms #-}
module TwinkleBear.Lesson05 (main) where
import Prelude hiding (init)
import Control.Applicative
import Control.Monad
import Data.Monoid
import Foreign.C.Types
import SDL.Vect
import qualified SDL
import Paths_sdl2 (getDataFileName)
#if !MIN_VERSION_base(4,8,0)
import Data.Foldable
#endif
screenWidth, screenHeight :: CInt
(screenWidth, screenHeight) = (640, 480)
spriteWidth, spriteHeight :: CInt
(spriteWidth, spriteHeight) = (100, 100)
type ClipRect = Maybe (SDL.Rectangle CInt)
data RenderPos = Centered | At (Point V2 CInt)
loadTexture :: SDL.Renderer -> FilePath -> IO SDL.Texture
loadTexture renderer path = do
bmp <- SDL.loadBMP path
SDL.createTextureFromSurface renderer bmp <* SDL.freeSurface bmp
renderTexture :: SDL.Renderer -> SDL.Texture -> ClipRect -> RenderPos -> IO ()
renderTexture renderer tex clipRect pos = do
ti <- SDL.queryTexture tex
let (w, h) = (SDL.textureWidth ti, SDL.textureHeight ti)
pos' = case pos of
At p -> p
Centered -> let cntr a b = (a - b) `div` 2
in P $ V2 (cntr screenWidth w) (cntr screenHeight h)
extent = V2 w h
SDL.copy renderer tex clipRect (Just $ SDL.Rectangle pos' extent)
main :: IO ()
main = do
SDL.initialize [ SDL.InitVideo ]
let winConfig = SDL.defaultWindow { SDL.windowInitialSize = V2 screenWidth screenHeight }
window <- SDL.createWindow "Lesson 5" winConfig
renderer <- SDL.createRenderer window (-1) SDL.defaultRenderer
spriteSheet <- getDataFileName "examples/twinklebear/spritesheet.bmp" >>= loadTexture renderer
let mkSprite x y = SDL.Rectangle (P (V2 (x * spriteWidth) (y * spriteHeight))) (V2 spriteWidth spriteHeight)
spriteOne = mkSprite 0 0
spriteTwo = mkSprite 0 1
spriteThree = mkSprite 1 0
spriteFour = mkSprite 1 1
let loop spriteRect = do
events <- SDL.pollEvents
let (Any quit, Last newSpriteRect) =
foldMap (\case
SDL.QuitEvent -> (Any True, mempty)
SDL.KeyboardEvent e ->
if | SDL.keyboardEventKeyMotion e == SDL.Pressed ->
case SDL.keysymScancode (SDL.keyboardEventKeysym e) of
SDL.Scancode1 -> (Any False, Last (Just spriteOne))
SDL.Scancode2 -> (Any False, Last (Just spriteTwo))
SDL.Scancode3 -> (Any False, Last (Just spriteThree))
SDL.Scancode4 -> (Any False, Last (Just spriteFour))
SDL.ScancodeQ -> (Any True, mempty)
_ -> mempty
| otherwise -> mempty
_ -> mempty) $
map SDL.eventPayload events
spriteRect' = newSpriteRect <|> spriteRect
SDL.clear renderer
renderTexture renderer spriteSheet spriteRect' Centered
SDL.present renderer
unless quit $ loop spriteRect'
loop $ Just spriteOne
SDL.destroyRenderer renderer
SDL.destroyWindow window
SDL.quit
|
