diff --git a/LICENSE b/LICENSE new file mode 100644 --- /dev/null +++ b/LICENSE @@ -0,0 +1,675 @@ + GNU GENERAL PUBLIC LICENSE + Version 3, 29 June 2007 + + Copyright (C) 2007 Free Software Foundation, Inc. + Everyone is permitted to copy and distribute verbatim copies + of this license document, but changing it is not allowed. + + Preamble + + The GNU General Public License is a free, copyleft license for +software and other kinds of works. + + The licenses for most software and other practical works are designed +to take away your freedom to share and change the works. By contrast, +the GNU General Public License is intended to guarantee your freedom to +share and change all versions of a program--to make sure it remains free +software for all its users. We, the Free Software Foundation, use the +GNU General Public License for most of our software; it applies also to +any other work released this way by its authors. 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If not, see . + +Also add information on how to contact you by electronic and paper mail. + + If the program does terminal interaction, make it output a short +notice like this when it starts in an interactive mode: + + Copyright (C) + This program comes with ABSOLUTELY NO WARRANTY; for details type `show w'. + This is free software, and you are welcome to redistribute it + under certain conditions; type `show c' for details. + +The hypothetical commands `show w' and `show c' should show the appropriate +parts of the General Public License. Of course, your program's commands +might be different; for a GUI interface, you would use an "about box". + + You should also get your employer (if you work as a programmer) or school, +if any, to sign a "copyright disclaimer" for the program, if necessary. +For more information on this, and how to apply and follow the GNU GPL, see +. + + The GNU General Public License does not permit incorporating your program +into proprietary programs. If your program is a subroutine library, you +may consider it more useful to permit linking proprietary applications with +the library. If this is what you want to do, use the GNU Lesser General +Public License instead of this License. But first, please read +. + diff --git a/Setup.hs b/Setup.hs new file mode 100644 --- /dev/null +++ b/Setup.hs @@ -0,0 +1,2 @@ +import Distribution.Simple +main = defaultMain diff --git a/SnowGlobe.hs b/SnowGlobe.hs new file mode 100644 --- /dev/null +++ b/SnowGlobe.hs @@ -0,0 +1,517 @@ +-- SnowGlobe -- randomized fractal snowflakes demo +-- (GPL3+) 2012 Claude Heiland-Allen +-- usage: snowglobe +-- 'f' toggles full screen, any other key to quit +-- tested with: ghc-7.0.4, ghc-7.4-rc1 + +import Numeric.LinearAlgebra hiding (i, reshape) +import qualified Numeric.LinearAlgebra as L +import Graphics.UI.GLUT hiding (scale) +import qualified Graphics.UI.GLUT as GL +import Graphics.Rendering.OpenGL.Raw + ( glTexImage2D, gl_TEXTURE_2D, gl_LUMINANCE32F, gl_LUMINANCE, gl_RGBA + , gl_UNSIGNED_BYTE, gl_FALSE, glClampColor, glGenerateMipmap + , gl_CLAMP_VERTEX_COLOR, gl_CLAMP_READ_COLOR, gl_CLAMP_FRAGMENT_COLOR + , glGenFramebuffers, glBindFramebuffer, glFramebufferTexture2D + , gl_FRAMEBUFFER, gl_COLOR_ATTACHMENT0, glUniformMatrix3fv + ) +import Control.Exception (evaluate) +import Control.Monad (forM_, replicateM, when) +import Data.IORef (IORef, modifyIORef, newIORef, readIORef, writeIORef) +import Data.List (foldl', minimumBy) +import Data.Ord (comparing) +import Data.Map (Map) +import qualified Data.Map as M +import qualified Data.Set as S +import System.Exit (exitSuccess) +import System.IO (hPutStrLn, stderr) +import System.Random (randomRIO) +import Unsafe.Coerce (unsafeCoerce) -- for OpenGL newtypes +import Foreign (alloca, peek, nullPtr, withArray) + +shader :: Maybe String -> Maybe String -> IO Program +shader mV mF = do + [p] <- genObjectNames 1 + vs <- case mV of + Nothing -> return [] + Just v -> do + [vert] <- genObjectNames 1 + shaderSource vert $= [ v ] + compileShader vert + msg <- get (shaderInfoLog vert) + when (not (null msg)) $ hPutStrLn stderr msg + return [vert] + fs <- case mF of + Nothing -> return [] + Just f -> do + [frag] <- genObjectNames 1 + shaderSource frag $= [ f ] + compileShader frag + msg <- get (shaderInfoLog frag) + when (not (null msg)) $ hPutStrLn stderr msg + return [frag] + attachedShaders p $= (vs, fs) + linkProgram p + msg <- get (programInfoLog p) + when (not (null msg)) $ hPutStrLn stderr msg + return p + +type N = Int +type R = Double +type V = L.Vector R +type M = L.Matrix R + +sum' :: Num a => [a] -> a +sum' = foldl' (+) 0 + +{-# RULES "realToFrac/glDouble" realToFrac = unsafeCoerceGLdouble #-} +unsafeCoerceGLdouble :: Double -> GLdouble +unsafeCoerceGLdouble = unsafeCoerce + +{-# RULES "realToFrac/glFloat" realToFrac = unsafeCoerceGLfloat #-} +unsafeCoerceGLfloat :: Float -> GLfloat +unsafeCoerceGLfloat = unsafeCoerce + +size :: N +size = 1024 + +er :: R +er = 4 + +accuracy :: R +accuracy = 1 / fromIntegral size + +tSize :: N +tSize = 512 + +maxSpeed :: R +maxSpeed = 10 + +data SnowGlobe = SnowGlobe + { pInitial :: Program, pInitial'er, pInitial'rho :: UniformLocation + , pStep :: Program, pStep'er, pStep'ts, pStep'src :: UniformLocation + , pColour :: Program, pColour'src, pColour'speed :: UniformLocation + , tPing, tPong :: TextureObject, fBuffer :: FramebufferObject + , sFlakes :: [Flake], sTextures :: Map N TextureObject + , wSize :: Size, wFullScreen :: Maybe Size + , sRenderFlake :: IO Render, sNextName :: N + } + +data Flake = Flake + { flakeName :: !N + , flakeTime :: !R + , flakePosition :: !V + , flakeVelocity :: !V + } + +flakeMass :: Flake -> R +flakeMass f = let s = flakeSize f in 1 + s * s + +flakeSize :: Flake -> R +flakeSize f = sin (pi * flakeTime f) + +flakeForce :: Flake -> V -> V +flakeForce f p = + let d = p - flakePosition f + [x,y] = toList d + m = let d2 = x * x + y * y in d2 * d2 + in scale (flakeMass f / m) d + +flakeUpdate :: R -> [Flake] -> Flake -> Flake +flakeUpdate dt fs f = f + { flakeTime = flakeTime f + dt / 2 + , flakePosition = flakePosition f + scale dt (flakeVelocity f) + , flakeVelocity = mapVector ((* maxSpeed) . tanh . (/ maxSpeed)) $ 0.999 * (flakeVelocity f + scale (dt / flakeMass f) (flakeField fs (flakePosition f))) + } + +flakeField :: [Flake] -> V -> V +flakeField fs p = sum' [ flakeForce f (p + d) | f <- fs, p /= flakePosition f, dx <- [-2,0,2], dy <- [-2,0,2], let d = 2|>[dx,dy] ] + +flakeSpawn :: [Flake] -> N -> IO Flake +flakeSpawn fs name = do + xs <- replicateM 32 $ randomRIO (-1, 1) + ys <- replicateM 32 $ randomRIO (-1, 1) + let ps = zipWith (\x y -> 2|>[x,y]) xs ys + p = fst . minimumBy (comparing snd) . map (\p' -> (p', norm2 (flakeField fs p'))) $ ps + return Flake{ flakeName = name, flakeTime = 0, flakePosition = p, flakeVelocity = 0 } + +flakesUpdate :: R -> [Flake] -> [Flake] +flakesUpdate dt fs = + let gs = map (flakeUpdate dt fs) fs + alive = filter ((< 1) . flakeTime) gs + in map flakeWrap alive + +flakeWrap :: Flake -> Flake +flakeWrap f = f{ flakePosition = mapVector wrap (flakePosition f) } + where + wrap x = + let y = (x + 1) / 2 + z = y - fromIntegral (floor y :: N) + in z * 2 - 1 + +-- amortized rendering over several frames +data Render = Done TextureObject | Step (IO Render) + +-- initial pass +flakeRenderStart :: IORef SnowGlobe -> IO Render +flakeRenderStart sR = do + s0 <- readIORef sR + p <- replicateM 4 $ randomRIO (0.02, 0.98) + let rts = flakeTransforms p + rho = maximum (map fst rts) + ts = map snd rts + passes = clamp 4 256 . round . logBase rho $ accuracy + loadIdentity + ortho2D 0 1 0 1 + viewport $= (Position 0 0, Size (fromIntegral size) (fromIntegral size)) + currentProgram $= Just (pInitial s0) + uniform (pInitial'er s0) $= TexCoord1 (realToFrac er :: GLfloat) + uniform (pInitial'rho s0) $= TexCoord1 (realToFrac rho :: GLfloat) + bindFBO (fBuffer s0) (tPing s0) + unitQuad + unbindFBO + currentProgram $= Nothing + return $ Step (flakeRenderPass sR ts passes passes) + +-- multi step passes +flakeRenderPass :: IORef SnowGlobe -> [M] -> N -> N -> IO Render +flakeRenderPass sR _ passes 0 = flakeRenderFinish sR passes +flakeRenderPass sR ts passes n = do + s0 <- readIORef sR + loadIdentity + ortho2D 0 1 0 1 + viewport $= (Position 0 0, Size (fromIntegral size) (fromIntegral size)) + currentProgram $= Just (pStep s0) + uniform (pStep'er s0) $= TexCoord1 (realToFrac er :: GLfloat) + uniform (pStep'src s0) $= TexCoord1 (0 :: GLint) + withArray (map ((realToFrac :: Float -> GLfloat) . (realToFrac :: Double -> Float)) . concat . concatMap L.toLists $ ts) $ glUniformMatrix3fv (unsafeCoerce $ pStep'ts s0) 6 1 + bindFBO (fBuffer s0) (tPong s0) + textureBinding Texture2D $= Just (tPing s0) + unitQuad + textureBinding Texture2D $= Nothing + unbindFBO + writeIORef sR s0{ tPing = tPong s0, tPong = tPing s0 } + currentProgram $= Nothing + if even n + then return $ Step (flakeRenderPass sR ts passes (n - 1)) + else flakeRenderPass sR ts passes (n - 1) + +-- colourize pass +flakeRenderFinish :: IORef SnowGlobe -> N -> IO Render +flakeRenderFinish sR passes = do + s0 <- readIORef sR + t <- newTexRGBA tSize + bindFBO (fBuffer s0) t + loadIdentity + ortho2D (-1) 1 (-1) 1 + viewport $= (Position 0 0, Size (fromIntegral tSize) (fromIntegral tSize)) + textureBinding Texture2D $= Just (tPong s0) + currentProgram $= Just (pColour s0) + uniform (pColour'src s0) $= TexCoord1 (0 :: GLint) + uniform (pColour'speed s0) $= TexCoord1 (1 / fromIntegral passes :: GLfloat) + fullQuad + currentProgram $= Nothing + unbindFBO + textureBinding Texture2D $= Just t + glGenerateMipmap gl_TEXTURE_2D + textureBinding Texture2D $= Nothing + return $ Done t + +transformRST :: R -> R -> V -> M +transformRST a l p = (3><3)[ c, s, x, -s, c, y, 0, 0, 1 ] + where x:y:_ = toList p + c = l * cos a + s = l * sin a + +flakeTransforms :: [R] -> [(R, M)] +flakeTransforms [a,b,c,d] = [(la,inv ta),(lb,inv tb),(lc,inv tc1),(ld,inv td1),(lc,inv tc2),(ld,inv td2)] + where + lx = a + b + ly = 2 * (c + d) + la = a / lx + lb = b / lx + lc = c / ly + ld = d / ly + u = 2|> [0, 0] + v = 2|> [0, la] + l = pi / 3 + ll = 2 * pi / 3 + r = -l + rr = -ll + ta = transformRST 0 la u + tb = transformRST 0 lb v + tc1 = transformRST l lc v + tc2 = transformRST r lc v + td1 = transformRST ll ld v + td2 = transformRST rr ld v +flakeTransforms _ = error "flakeTransforms" + +main :: IO () +main = do + _ <- getArgsAndInitialize + let wSize' = Size 1280 720 + initialWindowSize $= wSize' + initialDisplayMode $= [DoubleBuffered] + _ <- createWindow "SnowGlobe" + pInitial' <- shader Nothing (Just $ unlines + [ "uniform float er;" + , "uniform float rho;" + , "" + , "void main() {" + , " vec2 p = er * (gl_TexCoord[0].xy * 2.0 - vec2(1.0));" + , " float l = length(p);" + , " float n;" + , " if (l >= er) {" + , " n = 0.0;" + , " } else if (er > l && l >= rho * er) {" + , " n = (log(er) - log(l)) / -log(rho);" + , " } else {" + , " n = -1.0;" + , " }" + , " gl_FragData[0] = vec4(n);" + , "}" + ]) + pInitial'er' <- get $ uniformLocation pInitial' "er" + pInitial'rho' <- get $ uniformLocation pInitial' "rho" + pStep' <- shader Nothing (Just $ unlines + [ "uniform float er;" + , "uniform mat3 ts[6];" + , "" + , "uniform sampler2D src;" + , "" + , "void main() {" + , " vec2 p0 = er * (gl_TexCoord[0].xy * 2.0 - vec2(1.0));" + , " float m = -1.0;" + , " for (int i = 0; i < 6; ++i) {" + , " vec3 p = ts[i] * vec3(p0, 1.0);" + , " vec2 q = p.xy / p.z;" + , " float l = length(q);" + , " if (l < er) {" + , " m = max(m, texture2D(src, (q / er + vec2(1.0)) / 2.0).x);" + , " }" + , " }" + , " if (m >= 0.0) {" + , " m += 1.0;" + , " }" + , " m = max(m, texture2D(src, (p0 / er + vec2(1.0)) / 2.0).x);" + , " gl_FragData[0] = vec4(m);" + , "}" + ]) + pStep'er' <- get $ uniformLocation pStep' "er" + pStep'ts' <- get $ uniformLocation pStep' "ts" + pStep'src' <- get $ uniformLocation pStep' "src" + pColour' <- shader Nothing (Just $ unlines + [ "uniform sampler2D src;" + , "uniform float speed;" + , "" + , "void main() {" + , " vec2 p = gl_TexCoord[0].xy;" + , " float n = texture2D(src, p).x;" + , " p -= vec2(0.5);" + , " const mat2 r = mat2(0.5, 0.8660254037844386, -0.8660254037844386, 0.5);" + , " for (int i = 1; i < 6; ++i) {" + , " p = r * p;" + , " n = max(n, texture2D(src, p + vec2(0.5)).x);" + , " }" + , " if (n > 0.0) {" + , " n *= speed;" + , " } else {" + , " n = 0.0;" + , " }" + , " n *= n;" + , " n *= n;" + , " gl_FragData[0] = vec4(vec3(1.0), n);" + , "}" + ]) + pColour'src' <- get $ uniformLocation pColour' "src" + pColour'speed'<- get $ uniformLocation pColour' "speed" + tPing' <- newTex size + tPong' <- newTex size + fBuffer' <- newFBO + glClampColor gl_CLAMP_VERTEX_COLOR gl_FALSE + glClampColor gl_CLAMP_READ_COLOR gl_FALSE + glClampColor gl_CLAMP_FRAGMENT_COLOR gl_FALSE + sR <- newIORef SnowGlobe + { pInitial = pInitial', pInitial'er = pInitial'er', pInitial'rho = pInitial'rho' + , pStep = pStep', pStep'er = pStep'er', pStep'ts = pStep'ts', pStep'src = pStep'src' + , pColour = pColour', pColour'src = pColour'src', pColour'speed = pColour'speed' + , tPing = tPing', tPong = tPong', fBuffer = fBuffer' + , sFlakes = [], sTextures = M.empty, wSize = wSize', wFullScreen = Nothing + , sNextName = 0, sRenderFlake = return undefined + } + modifyIORef sR $ \s'->s'{ sRenderFlake = flakeRenderStart sR } + addTimerCallback 40 timer + displayCallback $= display sR + reshapeCallback $= Just (reshape sR) + keyboardMouseCallback $= Just (keyboard sR) + mainLoop + +keyboard :: IORef SnowGlobe -> Key -> KeyState -> Modifiers -> Position -> IO () +keyboard sR (SpecialKey KeyF11) Down _ _ = toggleFullScreen sR +keyboard sR (Char 'f') Down _ _ = toggleFullScreen sR +keyboard _ (Char _) Down _ _ = exitSuccess +keyboard _ _ _ _ _ = return () + +toggleFullScreen :: IORef SnowGlobe -> IO () +toggleFullScreen sR = do + s <- readIORef sR + case wFullScreen s of + Nothing -> do + writeIORef sR s{ wFullScreen = Just (wSize s) } + cursor $= None + fullScreen + Just ws -> do + writeIORef sR s{ wFullScreen = Nothing } + cursor $= Inherit + windowSize $= ws + +reshape :: IORef SnowGlobe -> Size -> IO () +reshape sR sz = do + s <- readIORef sR + writeIORef sR s{ wSize = sz } + +timer :: IO () +timer = do + addTimerCallback 40 timer + postRedisplay Nothing + +display' :: IORef SnowGlobe -> IO () +display' sR = do + update sR + s <- readIORef sR + _ <- evaluate (sum' . map flakeName . sFlakes $ s) + let names = S.fromList $ map flakeName (sFlakes s) + expired = S.filter (`S.notMember` names) (M.keysSet (sTextures s)) + sTextures' = foldr M.delete (sTextures s) (S.toList expired) + deleteObjectNames [sTextures s M.! n | n <- S.toList expired] + modifyIORef sR $ \s'->s'{ sTextures = sTextures' } + r <- sRenderFlake s + case r of + Done t -> do + f <- flakeSpawn (sFlakes s) (sNextName s) + modifyIORef sR $ \s'->s' + { sRenderFlake = flakeRenderStart sR + , sFlakes = f : sFlakes s' + , sTextures = M.insert (flakeName f) t (sTextures s') + , sNextName = sNextName s' + 1 + } + Step sRenderFlake' -> + modifyIORef sR $ \s'->s'{ sRenderFlake = sRenderFlake' } + +update :: IORef SnowGlobe -> IO () +update sR = do + s <- readIORef sR + let sFlakes' = flakesUpdate (1 / 256) (sFlakes s) + writeIORef sR (s{ sFlakes = sFlakes' }) + +display :: IORef SnowGlobe -> IO () +display sR = do + s <- readIORef sR + loadIdentity + let Size w h = wSize s + r = 0.7 + (x, y) + | h < w = (r, r * fromIntegral h / fromIntegral w) + | otherwise = (r * fromIntegral w / fromIntegral h, r) + ortho2D (-x) x (-y) y + viewport $= (Position 0 0, wSize s) + clearColor $= Color4 0 0 0.25 1 + clear [ColorBuffer] + texture Texture2D $= Enabled + blend $= Enabled + blendFunc $= (SrcAlpha, OneMinusSrcAlpha) + forM_ (sFlakes s) (flakeDraw s) + blend $= Disabled + texture Texture2D $= Disabled + swapBuffers + reportErrors + display' sR + +flakeDraw :: SnowGlobe -> Flake -> IO () +flakeDraw s f = do + let d :: GLdouble + d = realToFrac $ flakeSize f / 4 + a :: GLdouble + a = realToFrac $ 360 * flakeTime f * sin (fromIntegral (flakeName f)) + p :: GLdouble -> GLdouble -> IO () + p u v = do + texCoord $ TexCoord2 ((1+u)/2) ((1+v)/2) + vertex $ Vertex2 u v + x :: GLdouble + y :: GLdouble + [x, y] = map realToFrac . toList . flakePosition $ f + case flakeName f `M.lookup` sTextures s of + Nothing -> return () + t -> do + textureBinding Texture2D $= t + unsafePreservingMatrix $ do + translate $ Vector3 x y 0 + rotate a (Vector3 0 0 1) + GL.scale d d d + renderPrimitive Quads $ p (-1) (-1) >> p 1 (-1) >> p 1 1 >> p (-1) 1 + textureBinding Texture2D $= Nothing + +newTex :: N -> IO TextureObject +newTex s = do + [t] <- genObjectNames 1 + textureBinding Texture2D $= Just t + glTexImage2D gl_TEXTURE_2D 0 (fromIntegral gl_LUMINANCE32F) (fromIntegral s) (fromIntegral s) 0 gl_LUMINANCE gl_UNSIGNED_BYTE nullPtr + textureFilter Texture2D $= ((Linear', Nothing), Linear') + textureWrapMode Texture2D S $= (Repeated, ClampToEdge) + textureWrapMode Texture2D T $= (Repeated, ClampToEdge) + textureBinding Texture2D $= Nothing + return t + +newTexRGBA :: N -> IO TextureObject +newTexRGBA s = do + [t] <- genObjectNames 1 + textureBinding Texture2D $= Just t + glTexImage2D gl_TEXTURE_2D 0 (fromIntegral gl_RGBA) (fromIntegral s) (fromIntegral s) 0 gl_RGBA gl_UNSIGNED_BYTE nullPtr + textureFilter Texture2D $= ((Linear', Just Linear'), Linear') + textureWrapMode Texture2D S $= (Repeated, ClampToEdge) + textureWrapMode Texture2D T $= (Repeated, ClampToEdge) + textureBinding Texture2D $= Nothing + return t + +newtype FramebufferObject = FramebufferObject GLuint + +newFBO :: IO FramebufferObject +newFBO = fmap FramebufferObject (alloca $ \p -> glGenFramebuffers 1 p >> peek p) + +bindFBO :: FramebufferObject -> TextureObject -> IO () +bindFBO (FramebufferObject f) (TextureObject t) = do + glBindFramebuffer gl_FRAMEBUFFER f + glFramebufferTexture2D gl_FRAMEBUFFER gl_COLOR_ATTACHMENT0 gl_TEXTURE_2D t 0 + +unbindFBO :: IO () +unbindFBO = do + glFramebufferTexture2D gl_FRAMEBUFFER gl_COLOR_ATTACHMENT0 gl_TEXTURE_2D 0 0 + glBindFramebuffer gl_FRAMEBUFFER 0 + +fullQuad :: IO () +fullQuad = do + renderPrimitive Quads $ do + t (0.5-r) (0.5+r) >> v (-r2) ( r2) + t (0.5-r) (0.5-r) >> v (-r2) (-r2) + t (0.5+r) (0.5-r) >> v ( r2) (-r2) + t (0.5+r) (0.5+r) >> v ( r2) ( r2) + where + r = sqrt 0.5 / realToFrac er + r2 = 1 + t, v :: GLdouble -> GLdouble -> IO () + t x y = texCoord (TexCoord2 x y) + v x y = vertex (Vertex2 x y) + +unitQuad :: IO () +unitQuad = renderPrimitive Quads $ do + t 0 1 >> v 0 1 + t 0 0 >> v 0 0 + t 1 0 >> v 1 0 + t 1 1 >> v 1 1 + where + t, v :: GLdouble -> GLdouble -> IO () + t x y = texCoord (TexCoord2 x y) + v x y = vertex (Vertex2 x y) + +clamp :: Ord a => a -> a -> a -> a +clamp mi ma x = mi `max` x `min` ma diff --git a/snowglobe.cabal b/snowglobe.cabal new file mode 100644 --- /dev/null +++ b/snowglobe.cabal @@ -0,0 +1,16 @@ +Name: snowglobe +Version: 1 +Synopsis: randomized fractal snowflakes demo +Description: @snowglobe@ generates random snowflakes using iterated + function systems via OpenGL texture feedback. The + snowflakes interact in a particle system. +License: GPL-3 +License-file: LICENSE +Author: Claude Heiland-Allen +Maintainer: claudiusmaximus@goto10.org +Category: Demo +Build-type: Simple +Cabal-version: >=1.6 +Executable snowglobe + Main-is: SnowGlobe.hs + Build-depends: base < 5, containers == 0.4.*, random == 1.0.*, GLUT == 2.2.*, OpenGLRaw == 1.1.*, hmatrix == 0.13.*