Maintainer	gtk2hs-users@lists.sourceforge.net
Stability	provisional
Portability	portable (depends on GHC)
Safe Haskell	None
Language	Haskell98

Graphics.UI.Gtk.Gdk.GC

Contents

Detail

Description

Graphics contexts - objects to encapsulate drawing properties

Synopsis

data GC
class GObjectClass o => GCClass o
castToGC :: GObjectClass obj => obj -> GC
gTypeGC :: GType
gcNew :: DrawableClass d => d -> IO GC
data GCValues = GCValues Color Color Function Fill (Maybe Pixmap) (Maybe Pixmap) (Maybe Pixmap) SubwindowMode Int Int Int Int Bool Int LineStyle CapStyle JoinStyle
newGCValues :: GCValues
data Color = Color Word16 Word16 Word16
foreground :: GCValues -> Color
background :: GCValues -> Color
data Function
- = Copy
- | Invert
- | Xor
- | Clear
- | And
- | AndReverse
- | AndInvert
- | Noop
- | Or
- | Equiv
- | OrReverse
- | CopyInvert
- | OrInvert
- | Nand
- | Nor
- | Set
function :: GCValues -> Function
data Fill
- = Solid
- | Tiled
- | Stippled
- | OpaqueStippled
fill :: GCValues -> Fill
tile :: GCValues -> Maybe Pixmap
stipple :: GCValues -> Maybe Pixmap
clipMask :: GCValues -> Maybe Pixmap
data SubwindowMode
- = ClipByChildren
- | IncludeInferiors
subwindowMode :: GCValues -> SubwindowMode
tsXOrigin :: GCValues -> Int
tsYOrigin :: GCValues -> Int
clipXOrigin :: GCValues -> Int
clipYOrigin :: GCValues -> Int
graphicsExposure :: GCValues -> Bool
lineWidth :: GCValues -> Int
data LineStyle
- = LineSolid
- | LineOnOffDash
- | LineDoubleDash
lineStyle :: GCValues -> LineStyle
data CapStyle
- = CapNotLast
- | CapButt
- | CapRound
- | CapProjecting
capStyle :: GCValues -> CapStyle
data JoinStyle
- = JoinMiter
- | JoinRound
- | JoinBevel
joinStyle :: GCValues -> JoinStyle
gcNewWithValues :: DrawableClass d => d -> GCValues -> IO GC
gcSetValues :: GC -> GCValues -> IO ()
gcGetValues :: GC -> IO GCValues
gcSetClipRectangle :: GC -> Rectangle -> IO ()
gcSetClipRegion :: GC -> Region -> IO ()
gcSetDashes :: GC -> Int -> [(Int, Int)] -> IO ()

Detail

All drawing operations in Gdk take a graphics context (GC) argument. A graphics context encapsulates information about the way things are drawn, such as the foreground color or line width. By using graphics contexts, the number of arguments to each drawing call is greatly reduced, and communication overhead is minimized, since identical arguments do not need to be passed repeatedly.

Most values of a graphics context can be set at creation time by using gcNewWithValues. A few of the values in the GC, such as the dash pattern, can only be set by the latter method.

Graphics Contexts are removed in Gtk3, so this module is empty.

data GC #

Instances

Eq GC #
Instance details Defined in Graphics.UI.Gtk.Types Methods (==) :: GC -> GC -> Bool # (/=) :: GC -> GC -> Bool #
Ord GC #
Instance details Defined in Graphics.UI.Gtk.Types Methods compare :: GC -> GC -> Ordering # (<) :: GC -> GC -> Bool # (<=) :: GC -> GC -> Bool # (>) :: GC -> GC -> Bool # (>=) :: GC -> GC -> Bool # max :: GC -> GC -> GC # min :: GC -> GC -> GC #
GObjectClass GC #
Instance details Defined in Graphics.UI.Gtk.Types Methods toGObject :: GC -> GObject # unsafeCastGObject :: GObject -> GC #
GCClass GC #
Instance details Defined in Graphics.UI.Gtk.Types

class GObjectClass o => GCClass o #

Instances

GCClass GC #
Instance details Defined in Graphics.UI.Gtk.Types

castToGC :: GObjectClass obj => obj -> GC #

gTypeGC :: GType #

gcNew :: DrawableClass d => d -> IO GC #

Create an empty graphics context.

data GCValues #

Intermediate data structure for GCs.

If graphicsExposure is set then copying portions into a drawable will generate an "exposure" event, even if the destination area is not currently visible.

Removed in Gtk3.

Constructors

GCValues Color Color Function Fill (Maybe Pixmap) (Maybe Pixmap) (Maybe Pixmap) SubwindowMode Int Int Int Int Bool Int LineStyle CapStyle JoinStyle

Instances

Storable GCValues #

Instance details

Defined in Graphics.UI.Gtk.General.Structs

Methods

sizeOf :: GCValues -> Int #

alignment :: GCValues -> Int #

peekElemOff :: Ptr GCValues -> Int -> IO GCValues #

pokeElemOff :: Ptr GCValues -> Int -> GCValues -> IO () #

peekByteOff :: Ptr b -> Int -> IO GCValues #

pokeByteOff :: Ptr b -> Int -> GCValues -> IO () #

peek :: Ptr GCValues -> IO GCValues #

poke :: Ptr GCValues -> GCValues -> IO () #

newGCValues :: GCValues #

data Color #

Color

Specifies a color with three integer values for red, green and blue. All values range from 0 (least intense) to 65535 (highest intensity).

Constructors

Color Word16 Word16 Word16

Instances

Eq Color
Instance details Defined in Graphics.Rendering.Pango.Structs Methods (==) :: Color -> Color -> Bool # (/=) :: Color -> Color -> Bool #
Show Color
Instance details Defined in Graphics.Rendering.Pango.Structs Methods showsPrec :: Int -> Color -> ShowS # show :: Color -> String # showList :: [Color] -> ShowS #
Storable Color #
Instance details Defined in Graphics.UI.Gtk.General.Structs Methods sizeOf :: Color -> Int # alignment :: Color -> Int # peekElemOff :: Ptr Color -> Int -> IO Color # pokeElemOff :: Ptr Color -> Int -> Color -> IO () # peekByteOff :: Ptr b -> Int -> IO Color # pokeByteOff :: Ptr b -> Int -> Color -> IO () # peek :: Ptr Color -> IO Color # poke :: Ptr Color -> Color -> IO () #

foreground :: GCValues -> Color #

background :: GCValues -> Color #

data Function #

Determine how bitmap operations are carried out.

Removed in Gtk3.

Constructors

Copy
Invert
Xor
Clear
And
AndReverse
AndInvert
Noop
Or
Equiv
OrReverse
CopyInvert
OrInvert
Nand
Nor
Set

Instances

Enum Function #
Instance details Defined in Graphics.UI.Gtk.Gdk.Enums Methods succ :: Function -> Function # pred :: Function -> Function # toEnum :: Int -> Function # fromEnum :: Function -> Int # enumFrom :: Function -> [Function] # enumFromThen :: Function -> Function -> [Function] # enumFromTo :: Function -> Function -> [Function] # enumFromThenTo :: Function -> Function -> Function -> [Function] #
Eq Function #
Instance details Defined in Graphics.UI.Gtk.Gdk.Enums Methods (==) :: Function -> Function -> Bool # (/=) :: Function -> Function -> Bool #
Show Function #
Instance details Defined in Graphics.UI.Gtk.Gdk.Enums Methods showsPrec :: Int -> Function -> ShowS # show :: Function -> String # showList :: [Function] -> ShowS #

function :: GCValues -> Function #

data Fill #

How objects are filled.

Removed in Gtk3.

Constructors

Solid
Tiled
Stippled
OpaqueStippled

Instances

Enum Fill #
Instance details Defined in Graphics.UI.Gtk.Gdk.Enums Methods succ :: Fill -> Fill # pred :: Fill -> Fill # toEnum :: Int -> Fill # fromEnum :: Fill -> Int # enumFrom :: Fill -> [Fill] # enumFromThen :: Fill -> Fill -> [Fill] # enumFromTo :: Fill -> Fill -> [Fill] # enumFromThenTo :: Fill -> Fill -> Fill -> [Fill] #
Eq Fill #
Instance details Defined in Graphics.UI.Gtk.Gdk.Enums Methods (==) :: Fill -> Fill -> Bool # (/=) :: Fill -> Fill -> Bool #
Show Fill #
Instance details Defined in Graphics.UI.Gtk.Gdk.Enums Methods showsPrec :: Int -> Fill -> ShowS # show :: Fill -> String # showList :: [Fill] -> ShowS #

fill :: GCValues -> Fill #

tile :: GCValues -> Maybe Pixmap #

stipple :: GCValues -> Maybe Pixmap #

clipMask :: GCValues -> Maybe Pixmap #

data SubwindowMode #

Determine if child widget may be overdrawn.

Removed in Gtk3.

Constructors

ClipByChildren
IncludeInferiors

Instances

Enum SubwindowMode #	visibility of a window
Instance details Defined in Graphics.UI.Gtk.Gdk.Enums Methods succ :: SubwindowMode -> SubwindowMode # pred :: SubwindowMode -> SubwindowMode # toEnum :: Int -> SubwindowMode # fromEnum :: SubwindowMode -> Int # enumFrom :: SubwindowMode -> [SubwindowMode] # enumFromThen :: SubwindowMode -> SubwindowMode -> [SubwindowMode] # enumFromTo :: SubwindowMode -> SubwindowMode -> [SubwindowMode] # enumFromThenTo :: SubwindowMode -> SubwindowMode -> SubwindowMode -> [SubwindowMode] #
Eq SubwindowMode #
Instance details Defined in Graphics.UI.Gtk.Gdk.Enums Methods (==) :: SubwindowMode -> SubwindowMode -> Bool # (/=) :: SubwindowMode -> SubwindowMode -> Bool #
Show SubwindowMode #
Instance details Defined in Graphics.UI.Gtk.Gdk.Enums Methods showsPrec :: Int -> SubwindowMode -> ShowS # show :: SubwindowMode -> String # showList :: [SubwindowMode] -> ShowS #

subwindowMode :: GCValues -> SubwindowMode #

tsXOrigin :: GCValues -> Int #

tsYOrigin :: GCValues -> Int #

clipXOrigin :: GCValues -> Int #

clipYOrigin :: GCValues -> Int #

graphicsExposure :: GCValues -> Bool #

lineWidth :: GCValues -> Int #

data LineStyle #

Determines if a line is solid or dashed.

Removed in Gtk3.

Constructors

LineSolid
LineOnOffDash
LineDoubleDash

Instances

Enum LineStyle #
Instance details Defined in Graphics.UI.Gtk.Gdk.Enums Methods succ :: LineStyle -> LineStyle # pred :: LineStyle -> LineStyle # toEnum :: Int -> LineStyle # fromEnum :: LineStyle -> Int # enumFrom :: LineStyle -> [LineStyle] # enumFromThen :: LineStyle -> LineStyle -> [LineStyle] # enumFromTo :: LineStyle -> LineStyle -> [LineStyle] # enumFromThenTo :: LineStyle -> LineStyle -> LineStyle -> [LineStyle] #
Eq LineStyle #
Instance details Defined in Graphics.UI.Gtk.Gdk.Enums Methods (==) :: LineStyle -> LineStyle -> Bool # (/=) :: LineStyle -> LineStyle -> Bool #
Show LineStyle #
Instance details Defined in Graphics.UI.Gtk.Gdk.Enums Methods showsPrec :: Int -> LineStyle -> ShowS # show :: LineStyle -> String # showList :: [LineStyle] -> ShowS #

lineStyle :: GCValues -> LineStyle #

data CapStyle #

Specify the how the ends of a line is drawn.

Removed in Gtk3.

Constructors

CapNotLast
CapButt
CapRound
CapProjecting

Instances

Enum CapStyle #
Instance details Defined in Graphics.UI.Gtk.Gdk.Enums Methods succ :: CapStyle -> CapStyle # pred :: CapStyle -> CapStyle # toEnum :: Int -> CapStyle # fromEnum :: CapStyle -> Int # enumFrom :: CapStyle -> [CapStyle] # enumFromThen :: CapStyle -> CapStyle -> [CapStyle] # enumFromTo :: CapStyle -> CapStyle -> [CapStyle] # enumFromThenTo :: CapStyle -> CapStyle -> CapStyle -> [CapStyle] #
Eq CapStyle #
Instance details Defined in Graphics.UI.Gtk.Gdk.Enums Methods (==) :: CapStyle -> CapStyle -> Bool # (/=) :: CapStyle -> CapStyle -> Bool #
Show CapStyle #
Instance details Defined in Graphics.UI.Gtk.Gdk.Enums Methods showsPrec :: Int -> CapStyle -> ShowS # show :: CapStyle -> String # showList :: [CapStyle] -> ShowS #

capStyle :: GCValues -> CapStyle #

data JoinStyle #

Constructors

JoinMiter
JoinRound
JoinBevel

Instances

Enum JoinStyle #
Instance details Defined in Graphics.UI.Gtk.Gdk.Enums Methods succ :: JoinStyle -> JoinStyle # pred :: JoinStyle -> JoinStyle # toEnum :: Int -> JoinStyle # fromEnum :: JoinStyle -> Int # enumFrom :: JoinStyle -> [JoinStyle] # enumFromThen :: JoinStyle -> JoinStyle -> [JoinStyle] # enumFromTo :: JoinStyle -> JoinStyle -> [JoinStyle] # enumFromThenTo :: JoinStyle -> JoinStyle -> JoinStyle -> [JoinStyle] #
Eq JoinStyle #
Instance details Defined in Graphics.UI.Gtk.Gdk.Enums Methods (==) :: JoinStyle -> JoinStyle -> Bool # (/=) :: JoinStyle -> JoinStyle -> Bool #
Show JoinStyle #
Instance details Defined in Graphics.UI.Gtk.Gdk.Enums Methods showsPrec :: Int -> JoinStyle -> ShowS # show :: JoinStyle -> String # showList :: [JoinStyle] -> ShowS #

joinStyle :: GCValues -> JoinStyle #

gcNewWithValues :: DrawableClass d => d -> GCValues -> IO GC #

Creates a graphics context with specific values.

gcSetValues :: GC -> GCValues -> IO () #

Change some of the values of a graphics context.

gcGetValues :: GC -> IO GCValues #

Retrieve the values in a graphics context.

gcSetClipRectangle :: GC -> Rectangle -> IO () #

Set a clipping rectangle.

All drawing operations are restricted to this rectangle. This rectangle is interpreted relative to the clip origin.

gcSetClipRegion :: GC -> Region -> IO () #

Set a clipping region.

All drawing operations are restricted to this region. This region is interpreted relative to the clip origin.

gcSetDashes :: GC -> Int -> [(Int, Int)] -> IO () #

Specify the pattern with which lines are drawn.

Every tuple in the list contains an even and an odd segment. Even segments are drawn normally, whereby the lineStyle member of the graphics context defines if odd segements are drawn or not. A phase argument greater than 0 will drop phase pixels before starting to draw.