| Safe Haskell | Safe |
|---|---|
| Language | Haskell2010 |
Graphics.Vty.Attributes
Description
Display attributes
Attributes have three components: a foreground color, a background
color, and a style mask. The simplest attribute is the default
attribute, or defAttr. Attributes can be modified with
withForeColor, withBackColor, and withStyle, e.g.,
defAttr `withForeColor` red
Image constructors often require an Attr to indicate the
attributes used in the image, e.g.,
string (defAttr `withForeColor` red) "this text will be red"
The appearance of Images using defAttr is determined by the The
terminal, so this is not something VTY can control. The user is free
to The define the color scheme of the terminal as they see fit.
The value currentAttr will keep the attributes of whatever was
output previously.
Synopsis
- data Attr = Attr {
- attrStyle :: !(MaybeDefault Style)
- attrForeColor :: !(MaybeDefault Color)
- attrBackColor :: !(MaybeDefault Color)
- attrURL :: !(MaybeDefault Text)
- data FixedAttr = FixedAttr {
- fixedStyle :: !Style
- fixedForeColor :: !(Maybe Color)
- fixedBackColor :: !(Maybe Color)
- fixedURL :: !(Maybe Text)
- data MaybeDefault v where
- Default :: MaybeDefault v
- KeepCurrent :: MaybeDefault v
- SetTo :: forall v. (Eq v, Show v, Read v) => !v -> MaybeDefault v
- defAttr :: Attr
- currentAttr :: Attr
- type Style = Word8
- withStyle :: Attr -> Style -> Attr
- standout :: Style
- italic :: Style
- underline :: Style
- reverseVideo :: Style
- blink :: Style
- dim :: Style
- bold :: Style
- defaultStyleMask :: Style
- styleMask :: Attr -> Word8
- hasStyle :: Style -> Style -> Bool
- withForeColor :: Attr -> Color -> Attr
- withBackColor :: Attr -> Color -> Attr
- withURL :: Attr -> Text -> Attr
- data Color
- black :: Color
- red :: Color
- green :: Color
- yellow :: Color
- blue :: Color
- magenta :: Color
- cyan :: Color
- white :: Color
- brightBlack :: Color
- brightRed :: Color
- brightGreen :: Color
- brightYellow :: Color
- brightBlue :: Color
- brightMagenta :: Color
- brightCyan :: Color
- brightWhite :: Color
- rgbColor :: Integral i => i -> i -> i -> Color
- color240CodeToRGB :: Word8 -> Maybe (Int, Int, Int)
Documentation
A display attribute defines the Color and Style of all the characters rendered after the attribute is applied.
At most 256 colors, picked from a 240 and 16 color palette, are possible for the background and foreground. The 240 colors and 16 colors are points in different palettes. See Color for more information.
Constructors
| Attr | |
Fields
| |
Instances
| Eq Attr Source # | |
| Read Attr Source # | |
| Show Attr Source # | |
| Generic Attr Source # | |
| Semigroup Attr Source # | |
| Monoid Attr Source # | |
| NFData Attr Source # | |
Defined in Graphics.Vty.Attributes | |
| type Rep Attr Source # | |
Defined in Graphics.Vty.Attributes type Rep Attr = D1 (MetaData "Attr" "Graphics.Vty.Attributes" "vty-5.25.1-JV5SYMfdUkdCGOV9l3bLa3" False) (C1 (MetaCons "Attr" PrefixI True) ((S1 (MetaSel (Just "attrStyle") NoSourceUnpackedness SourceStrict DecidedStrict) (Rec0 (MaybeDefault Style)) :*: S1 (MetaSel (Just "attrForeColor") NoSourceUnpackedness SourceStrict DecidedStrict) (Rec0 (MaybeDefault Color))) :*: (S1 (MetaSel (Just "attrBackColor") NoSourceUnpackedness SourceStrict DecidedStrict) (Rec0 (MaybeDefault Color)) :*: S1 (MetaSel (Just "attrURL") NoSourceUnpackedness SourceStrict DecidedStrict) (Rec0 (MaybeDefault Text))))) | |
Specifies the display attributes such that the final style and color values do not depend on the previously applied display attribute. The display attributes can still depend on the terminal's default colors (unfortunately).
Constructors
| FixedAttr | |
Fields
| |
data MaybeDefault v where Source #
The style and color attributes can either be the terminal defaults. Or be equivalent to the previously applied style. Or be a specific value.
Constructors
| Default :: MaybeDefault v | |
| KeepCurrent :: MaybeDefault v | |
| SetTo :: forall v. (Eq v, Show v, Read v) => !v -> MaybeDefault v |
Instances
Sets the style, background color and foreground color to the default values for the terminal. There is no easy way to determine what the default background and foreground colors are.
currentAttr :: Attr Source #
Keeps the style, background color and foreground color that was previously set. Used to override some part of the previous style.
EG: current_style withForeColor brightMagenta
Would be the currently applied style (be it underline, bold, etc) but with the foreground color set to brightMagenta.
Styles
Styles are represented as an 8 bit word. Each bit in the word is 1 if the style attribute assigned to that bit should be applied and 0 if the style attribute should not be applied.
The 7 possible style attributes:
- standout
- underline
- reverseVideo
- blink
- dim
- bold/bright
- italic
(The invisible, protect, and altcharset display attributes some terminals support are not supported via VTY.)
The 7 possible style attributes:
- standout
- underline
- reverseVideo
- blink
- dim
- bold/bright
- italic
(The invisible, protect, and altcharset display attributes some terminals support are not supported via VTY.)
The 7 possible style attributes:
- standout
- underline
- reverseVideo
- blink
- dim
- bold/bright
- italic
(The invisible, protect, and altcharset display attributes some terminals support are not supported via VTY.)
reverseVideo :: Style Source #
The 7 possible style attributes:
- standout
- underline
- reverseVideo
- blink
- dim
- bold/bright
- italic
(The invisible, protect, and altcharset display attributes some terminals support are not supported via VTY.)
The 7 possible style attributes:
- standout
- underline
- reverseVideo
- blink
- dim
- bold/bright
- italic
(The invisible, protect, and altcharset display attributes some terminals support are not supported via VTY.)
The 7 possible style attributes:
- standout
- underline
- reverseVideo
- blink
- dim
- bold/bright
- italic
(The invisible, protect, and altcharset display attributes some terminals support are not supported via VTY.)
The 7 possible style attributes:
- standout
- underline
- reverseVideo
- blink
- dim
- bold/bright
- italic
(The invisible, protect, and altcharset display attributes some terminals support are not supported via VTY.)
hasStyle :: Style -> Style -> Bool Source #
true if the given Style value has the specified Style set.
Setting attribute colors
Setting hyperlinks
withURL :: Attr -> Text -> Attr Source #
Add a hyperlinked URL using the proposed escape sequences for
hyperlinked
URLs.
These escape sequences are comparatively new and aren't widely
supported in terminal emulators yet, but most terminal emulators
that don't know about these sequences will ignore these sequences,
and therefore this should fall back sensibly. In some cases they
won't and this will result in garbage, so this is why hyperlinking is
disabled by default, in which case this combinator has no observable
effect. To enable it, enable Hyperlink mode on your Vty output
interface.
Colors
Abstract data type representing a color.
Currently the foreground and background color are specified as points in either a:
- 16 color palette. Where the first 8 colors are equal to the 8 colors of the ISO 6429 (ANSI) 8 color palette and the second 8 colors are bright/vivid versions of the first 8 colors.
- 240 color palette. This palette is a regular sampling of the full RGB colorspace for the first 224 colors. The remaining 16 colors is a greyscale palette.
The 8 ISO 6429 (ANSI) colors are as follows:
- black
- red
- green
- yellow
- blue
- magenta
- cyan
- white
The mapping from points in the 240 color palette to colors actually displayable by the terminal depends on the number of colors the terminal claims to support. Which is usually determined by the terminfo "colors" property. If this property is not being accurately reported then the color reproduction will be incorrect.
If the terminal reports <= 16 colors then the 240 color palette points are only mapped to the 8 color pallete. I'm not sure of the RGB points for the "bright" colors which is why they are not addressable via the 240 color palette.
If the terminal reports > 16 colors then the 240 color palette points are mapped to the nearest points in a ("color count" - 16) subsampling of the 240 color palette.
All of this assumes the terminals are behaving similarly to xterm and rxvt when handling colors. And that the individual colors have not been remapped by the user. There may be a way to verify this through terminfo but I don't know it.
Seriously, terminal color support is INSANE.
Instances
| Eq Color Source # | |
| Read Color Source # | |
| Show Color Source # | |
| Generic Color Source # | |
| NFData Color Source # | |
Defined in Graphics.Vty.Attributes.Color | |
| type Rep Color Source # | |
Defined in Graphics.Vty.Attributes.Color type Rep Color = D1 (MetaData "Color" "Graphics.Vty.Attributes.Color" "vty-5.25.1-JV5SYMfdUkdCGOV9l3bLa3" False) (C1 (MetaCons "ISOColor" PrefixI False) (S1 (MetaSel (Nothing :: Maybe Symbol) NoSourceUnpackedness SourceStrict DecidedStrict) (Rec0 Word8)) :+: C1 (MetaCons "Color240" PrefixI False) (S1 (MetaSel (Nothing :: Maybe Symbol) NoSourceUnpackedness SourceStrict DecidedStrict) (Rec0 Word8))) | |
brightBlack :: Color Source #
Bright/Vivid variants of the standard 8-color ANSI
brightGreen :: Color Source #
Bright/Vivid variants of the standard 8-color ANSI
brightYellow :: Color Source #
Bright/Vivid variants of the standard 8-color ANSI
brightBlue :: Color Source #
brightCyan :: Color Source #
brightWhite :: Color Source #