[Gtk2hs-commit] (main branch): add a surface type for raw data, plus a demo program showing how to use this with SDL (code supplied by Eli Frey)

[Daniel W. <dm...@lu...>]

diffing dir...
Sun Apr 22 20:52:06 BST 2012  Daniel Wagner <da...@wa...>
  * add a surface type for raw data, plus a demo program showing how to use this with SDL (code supplied by Eli Frey)
  Ignore-this: 254fd58bd2322a9fecb5449741d7a697
    hunk ./cairo/Graphics/Rendering/Cairo.hs 200
    +  , withImageSurfaceForData
    hunk ./cairo/Graphics/Rendering/Cairo.hs 204
    +  , createImageSurfaceForData
    hunk ./cairo/Graphics/Rendering/Cairo.hs 1688
    +-- | Like 'withImageSurface' but creating a surface to target external
    +-- data pointed to by 'PixelData'.
    +--
    +withImageSurfaceForData ::
    +     PixelData         -- ^ pointer to pixel data
    +  -> Format            -- ^ format of pixels in the surface to create
    +  -> Int               -- ^ width of the surface, in pixels
    +  -> Int               -- ^ height of the surface, in pixels
    +  -> Int               -- ^ size of stride between rows in the surface to create
    +  -> (Surface -> IO a) -- ^ an action that may use the surface. The surface is
    +                       -- only valid within this action
    +  -> IO a
    +withImageSurfaceForData pixels format width height stride f =
    +  bracket (Internal.imageSurfaceCreateForData pixels format width height stride)
    +          (\surface -> do status <- Internal.surfaceStatus surface
    +                          Internal.surfaceDestroy surface
    +                          unless (status == StatusSuccess) $
    +                            Internal.statusToString status >>= fail)
    +          (\surface -> f surface)
    +
    +-- | Like 'createImageSurface' but creating a surface to target external
    +-- data pointed to by 'PixelData'.
    +--
    +createImageSurfaceForData ::
    +     PixelData         -- ^ pointer to pixel data
    +  -> Format            -- ^ format of pixels in the surface to create
    +  -> Int               -- ^ width of the surface, in pixels
    +  -> Int               -- ^ height of the surface, in pixels
    +  -> Int               -- ^ size of stride between rows in the surface to create
    +  -> IO Surface
    +createImageSurfaceForData pixels format width height stride = do
    +  surface <- Internal.imageSurfaceCreateForData pixels format width height stride
    +  Internal.manageSurface surface
    +  return surface
    +
    hunk ./cairo/Graphics/Rendering/Cairo/Internal/Surfaces/Image.chs 24
    +{#fun image_surface_create_for_data as imageSurfaceCreateForData
    +  { id `Ptr CUChar'
    +  , cFromEnum `Format'
    +  , `Int'
    +  , `Int'
    +  , `Int'
    +  } -> `Surface' mkSurface*#}
    +
    hunk ./cairo/Graphics/Rendering/Cairo/Types.chs 17
    -    Matrix(Matrix), MatrixPtr
    +    PixelData
    +  , Matrix(Matrix), MatrixPtr
    hunk ./cairo/Graphics/Rendering/Cairo/Types.chs 67
    +type PixelData = Ptr CUChar
    +
    addfile ./cairo/demo/CairoSDL.hs
    hunk ./cairo/demo/CairoSDL.hs 1
    +import qualified Graphics.UI.SDL as SDL
    +import Graphics.Rendering.Cairo
    +import Foreign.Ptr ( castPtr )
    +
    +demo1 :: Render ()
    +demo1 = do
    +  setSourceRGB 0 0 0
    +  moveTo 100 100
    +  lineTo 500 500
    +  stroke
    +
    +demo2 :: Render ()
    +demo2 = do
    +  setSourceRGB 0 0 0
    +  moveTo 500 100
    +  lineTo 100 500
    +  stroke
    +
    +main = SDL.withInit [ SDL.InitVideo ] $ do
    +  screen <- SDL.setVideoMode 600 600 32 [ SDL.SWSurface ]
    +
    +  SDL.fillRect screen Nothing (SDL.Pixel maxBound)
    +
    +  pixels <- fmap castPtr $ SDL.surfaceGetPixels screen
    +
    +  canvas <- createImageSurfaceForData pixels FormatRGB24 600 600 (600 * 4)
    +  renderWith canvas demo1
    +
    +  withImageSurfaceForData pixels FormatRGB24 600 600 (600 * 4) $ \canvas ->
    +    renderWith canvas demo2
    +
    +  SDL.flip screen
    +
    +  idle
    +  where
    +  idle = do
    +    e <- SDL.waitEvent
    +    case e of
    +         SDL.Quit  -> return ()
    +         otherwise -> idle
    hunk ./cairo/demo/Makefile 2
    -PROGS  = drawing drawing2 starandring text clock graph
    -SOURCES = Drawing.hs Drawing2.hs StarAndRing.hs Text.hs Clock.hs Graph.hs
    +PROGS  = drawing drawing2 starandring text clock graph sdldrawing
    +SOURCES = Drawing.hs Drawing2.hs StarAndRing.hs Text.hs Clock.hs Graph.hs CairoSDL.hs
    hunk ./cairo/demo/Makefile 25
    +sdldrawing : CairoSDL.hs
    +	$(HC_RULE)
    +