opengl - 使用基于递归的动画时，在drawPicture.“Gloss/OpenGL Stack Overflow ”之后出现“”错误

只是为了混入Haskell的Gloss库，我写道:

import Graphics.Gloss

data World = World { worldBugs :: [Picture] }

bug :: Point -> Float -> Picture
bug (x, y) s =
    let head = Translate x (y - s) $ Circle (s * 0.8)
        body = Translate x (y + s) $ Circle (s * 1.2)
    in  pictures [head, body]

main = play (InWindow "Animation Test" (400, 400) (100, 100)) white 10
    (World . map (\(n,b) -> Translate (n * 20) (n * 20) $ b) $ zip [0..] $ replicate 100 $ bug (0,0) 100)
    (\world -> pictures $ worldBugs world)
    (\event world -> world)
    (\time (World bs) -> World $ map (Rotate (time * 10)) bs)

它显示一些随着时间的流逝旋转的“虫子”(两个圆圈形成一个头部和一个躯干)。问题是，运行了几秒钟之后，它崩溃了:

Gloss / OpenGL Stack Overflow "after drawPicture."
  This program uses the Gloss vector graphics library, which tried to
  draw a picture using more nested transforms (Translate/Rotate/Scale)
  than your OpenGL implementation supports. The OpenGL spec requires
  all implementations to have a transform stack depth of at least 32,
  and Gloss tries not to push the stack when it doesn't have to, but
  that still wasn't enough.

  You should complain to your harware vendor that they don't provide
  a better way to handle this situation at the OpenGL API level.

  To make this program work you'll need to reduce the number of nested
  transforms used when defining the Picture given to Gloss. Sorry.

如果我正确理解的话，这基本上意味着最终将太多的转换放入堆栈中，并且溢出。它指出这可能是硬件限制(我在Surface 2 Pro上)，所以我是SOL吗？使用animate时，它不会执行此操作，但这可能是由于它没有在每个滴答声中传递状态。

如果要制作游戏，则必须使用play将状态传递给下一个刻度。我不能一切都按时完成。有没有解决的办法？谷歌搜索错误几乎没有产生。

最佳答案

问题在于，在每个“刻度”上，它都通过将图片包装在另一个转换中进一步嵌套了图片(最终导致溢出)。为了解决这个问题
我只是将每个值存储在Entity对象中，然后在fromEntity上应用了一次转换。

    {- LANGUAGE threaded -}
module GlossTest where

import Graphics.Gloss

data Entity = Entity { entRot :: Float, entTrans :: Point, entScale :: Point, entPict :: Picture }

data World = World { worldBugs :: [Entity] }

entTranslate :: Float -> Float -> Entity -> Entity
entTranslate x y (Entity r t s p) = Entity r (x,y) s p

entRotate :: Float -> Entity -> Entity
entRotate x (Entity r t s p) = Entity x t s p

entRotateBy :: Float -> Entity -> Entity
entRotateBy n (Entity r t s p) = Entity (r + n) t s p

entMove :: Float -> Float -> Entity -> Entity
entMove x y (Entity r (tX,tY) s p) = Entity r (tX + x, tY + y) s p

toEntity :: Picture -> Entity
toEntity = Entity 0 (0,0) 1

fromEntity :: Entity -> Picture
fromEntity (Entity r (tX,tY) (sX,sY) p) = Rotate r . Translate tX tY $ Scale sX sY p

bug :: Point -> Float -> Entity
bug (x, y) s =
    let head = Rotate 0 $ Translate x (y - s) $ Circle (s * 0.8)
        body = Rotate 0 $ Translate x (y + s) $ Circle (s * 1.2)
    in  toEntity $ pictures [head, body]

main = play
    (InWindow "Animation Test" (400, 400) (100, 100)) white 1
    (World . map (\(n,b) -> entTranslate (n * 1) (n * 1) $ b) $ zip [0..] $ replicate 10 $ bug (0,0) 100)
    (\world -> pictures . map fromEntity $ worldBugs world)
    (\event world -> world)
    (\time (World bs) -> World $ map (\(n,b) -> entRotateBy (n * time) $ entMove time time b) $ zip [0..] bs)

关于opengl - 使用基于递归的动画时，在drawPicture.“Gloss/OpenGL Stack Overflow ”之后出现“”错误，我们在Stack Overflow上找到一个类似的问题：https://stackoverflow.com/questions/26599365/