VideoDither.hs


{- |
Copyright  : Will Thompson, Iñaki García Etxebarria and Jonas Platte
License    : LGPL-2.1
Maintainer : Iñaki García Etxebarria (inaki@blueleaf.cc)

GstVideoDither provides implementations of several dithering algorithms
that can be applied to lines of video pixels to quantize and dither them.
-}

#define ENABLE_OVERLOADING (MIN_VERSION_haskell_gi_overloading(1,0,0) \
       && !defined(__HADDOCK_VERSION__))

module GI.GstVideo.Structs.VideoDither
    ( 

-- * Exported types
    VideoDither(..)                         ,
    noVideoDither                           ,


 -- * Methods
-- ** free #method:free#

#if ENABLE_OVERLOADING
    VideoDitherFreeMethodInfo               ,
#endif
    videoDitherFree                         ,


-- ** line #method:line#

#if ENABLE_OVERLOADING
    VideoDitherLineMethodInfo               ,
#endif
    videoDitherLine                         ,




    ) where

import Data.GI.Base.ShortPrelude
import qualified Data.GI.Base.ShortPrelude as SP
import qualified Data.GI.Base.Overloading as O
import qualified Prelude as P

import qualified Data.GI.Base.Attributes as GI.Attributes
import qualified Data.GI.Base.ManagedPtr as B.ManagedPtr
import qualified Data.GI.Base.GClosure as B.GClosure
import qualified Data.GI.Base.GError as B.GError
import qualified Data.GI.Base.GVariant as B.GVariant
import qualified Data.GI.Base.GValue as B.GValue
import qualified Data.GI.Base.GParamSpec as B.GParamSpec
import qualified Data.GI.Base.CallStack as B.CallStack
import qualified Data.GI.Base.Properties as B.Properties
import qualified Data.Text as T
import qualified Data.ByteString.Char8 as B
import qualified Data.Map as Map
import qualified Foreign.Ptr as FP
import qualified GHC.OverloadedLabels as OL


-- | Memory-managed wrapper type.
newtype VideoDither = VideoDither (ManagedPtr VideoDither)
-- XXX Wrapping a foreign struct/union with no known destructor or size, leak?
instance WrappedPtr VideoDither where
    wrappedPtrCalloc = return nullPtr
    wrappedPtrCopy = return
    wrappedPtrFree = Nothing

-- | A convenience alias for `Nothing` :: `Maybe` `VideoDither`.
noVideoDither :: Maybe VideoDither
noVideoDither = Nothing


#if ENABLE_OVERLOADING
instance O.HasAttributeList VideoDither
type instance O.AttributeList VideoDither = VideoDitherAttributeList
type VideoDitherAttributeList = ('[ ] :: [(Symbol, *)])
#endif

-- method VideoDither::free
-- method type : OrdinaryMethod
-- Args : [Arg {argCName = "dither", argType = TInterface (Name {namespace = "GstVideo", name = "VideoDither"}), direction = DirectionIn, mayBeNull = False, argDoc = Documentation {rawDocText = Just "a #GstVideoDither", sinceVersion = Nothing}, argScope = ScopeTypeInvalid, argClosure = -1, argDestroy = -1, argCallerAllocates = False, transfer = TransferNothing}]
-- Lengths : []
-- returnType : Nothing
-- throws : False
-- Skip return : False

foreign import ccall "gst_video_dither_free" gst_video_dither_free :: 
    Ptr VideoDither ->                      -- dither : TInterface (Name {namespace = "GstVideo", name = "VideoDither"})
    IO ()

{- |
Free /@dither@/
-}
videoDitherFree ::
    (B.CallStack.HasCallStack, MonadIO m) =>
    VideoDither
    {- ^ /@dither@/: a 'GI.GstVideo.Structs.VideoDither.VideoDither' -}
    -> m ()
videoDitherFree dither = liftIO $ do
    dither' <- unsafeManagedPtrGetPtr dither
    gst_video_dither_free dither'
    touchManagedPtr dither
    return ()

#if ENABLE_OVERLOADING
data VideoDitherFreeMethodInfo
instance (signature ~ (m ()), MonadIO m) => O.MethodInfo VideoDitherFreeMethodInfo VideoDither signature where
    overloadedMethod _ = videoDitherFree

#endif

-- method VideoDither::line
-- method type : OrdinaryMethod
-- Args : [Arg {argCName = "dither", argType = TInterface (Name {namespace = "GstVideo", name = "VideoDither"}), direction = DirectionIn, mayBeNull = False, argDoc = Documentation {rawDocText = Just "a #GstVideoDither", sinceVersion = Nothing}, argScope = ScopeTypeInvalid, argClosure = -1, argDestroy = -1, argCallerAllocates = False, transfer = TransferNothing},Arg {argCName = "line", argType = TBasicType TPtr, direction = DirectionIn, mayBeNull = True, argDoc = Documentation {rawDocText = Just "pointer to the pixels of the line", sinceVersion = Nothing}, argScope = ScopeTypeInvalid, argClosure = -1, argDestroy = -1, argCallerAllocates = False, transfer = TransferNothing},Arg {argCName = "x", argType = TBasicType TUInt, direction = DirectionIn, mayBeNull = False, argDoc = Documentation {rawDocText = Just "x coordinate", sinceVersion = Nothing}, argScope = ScopeTypeInvalid, argClosure = -1, argDestroy = -1, argCallerAllocates = False, transfer = TransferNothing},Arg {argCName = "y", argType = TBasicType TUInt, direction = DirectionIn, mayBeNull = False, argDoc = Documentation {rawDocText = Just "y coordinate", sinceVersion = Nothing}, argScope = ScopeTypeInvalid, argClosure = -1, argDestroy = -1, argCallerAllocates = False, transfer = TransferNothing},Arg {argCName = "width", argType = TBasicType TUInt, direction = DirectionIn, mayBeNull = False, argDoc = Documentation {rawDocText = Just "the width", sinceVersion = Nothing}, argScope = ScopeTypeInvalid, argClosure = -1, argDestroy = -1, argCallerAllocates = False, transfer = TransferNothing}]
-- Lengths : []
-- returnType : Nothing
-- throws : False
-- Skip return : False

foreign import ccall "gst_video_dither_line" gst_video_dither_line :: 
    Ptr VideoDither ->                      -- dither : TInterface (Name {namespace = "GstVideo", name = "VideoDither"})
    Ptr () ->                               -- line : TBasicType TPtr
    Word32 ->                               -- x : TBasicType TUInt
    Word32 ->                               -- y : TBasicType TUInt
    Word32 ->                               -- width : TBasicType TUInt
    IO ()

{- |
Dither /@width@/ pixels starting from offset /@x@/ in /@line@/ using /@dither@/.

/@y@/ is the line number of /@line@/ in the output image.
-}
videoDitherLine ::
    (B.CallStack.HasCallStack, MonadIO m) =>
    VideoDither
    {- ^ /@dither@/: a 'GI.GstVideo.Structs.VideoDither.VideoDither' -}
    -> Ptr ()
    {- ^ /@line@/: pointer to the pixels of the line -}
    -> Word32
    {- ^ /@x@/: x coordinate -}
    -> Word32
    {- ^ /@y@/: y coordinate -}
    -> Word32
    {- ^ /@width@/: the width -}
    -> m ()
videoDitherLine dither line x y width = liftIO $ do
    dither' <- unsafeManagedPtrGetPtr dither
    gst_video_dither_line dither' line x y width
    touchManagedPtr dither
    return ()

#if ENABLE_OVERLOADING
data VideoDitherLineMethodInfo
instance (signature ~ (Ptr () -> Word32 -> Word32 -> Word32 -> m ()), MonadIO m) => O.MethodInfo VideoDitherLineMethodInfo VideoDither signature where
    overloadedMethod _ = videoDitherLine

#endif

#if ENABLE_OVERLOADING
type family ResolveVideoDitherMethod (t :: Symbol) (o :: *) :: * where
    ResolveVideoDitherMethod "free" o = VideoDitherFreeMethodInfo
    ResolveVideoDitherMethod "line" o = VideoDitherLineMethodInfo
    ResolveVideoDitherMethod l o = O.MethodResolutionFailed l o

instance (info ~ ResolveVideoDitherMethod t VideoDither, O.MethodInfo info VideoDither p) => OL.IsLabel t (VideoDither -> p) where
#if MIN_VERSION_base(4,10,0)
    fromLabel = O.overloadedMethod (O.MethodProxy :: O.MethodProxy info)
#else
    fromLabel _ = O.overloadedMethod (O.MethodProxy :: O.MethodProxy info)
#endif

#endif