Graphics.Vty.Picture

Documentation

data Picture

A Vty picture.

These can be constructed directly or using picForImage.

Constructors

Picture

Fields

• picCursor :: Cursor

  The picture's cursor.

• picLayers :: [Image]

  The picture's image layers (top-most first).

• picBackground :: Background

  The picture's background to be displayed in locations with no Image data.

Instances

Show Picture

Defined in Graphics.Vty.Picture

Methods

showsPrec :: Int -> Picture -> ShowS

show :: Picture -> String

showList :: [Picture] -> ShowS

NFData Picture

Defined in Graphics.Vty.Picture

Methods

rnf :: Picture -> ()

Eq Picture

Defined in Graphics.Vty.Picture

Methods

(==) :: Picture -> Picture -> Bool

(/=) :: Picture -> Picture -> Bool

data Cursor

A picture can be configured to hide the cursor or to show the cursor at the specified character position.

There is not a 1:1 map from character positions to a row and column on the screen due to characters that take more than 1 column.

Constructors

NoCursor

Hide the cursor

PositionOnly !Bool !Int !Int

Set the terminal's cursor position without displaying a cursor character. This is important for accessibility with screen readers where a cursor position needs to be reported but we may not want to show a block cursor in that location for cosmetic reasons. The boolean argument indicates whether the positioning should be absolute as with AbsoluteCursor (True) or logical as with Cursor (False).

Cursor !Int !Int

Show the cursor at the given logical column accounting for character width in the presence of multi-column characters.

AbsoluteCursor !Int !Int

Show the cursor at the given absolute terminal column and row

Instances

Show Cursor

Defined in Graphics.Vty.Picture

Methods

showsPrec :: Int -> Cursor -> ShowS

show :: Cursor -> String

showList :: [Cursor] -> ShowS

NFData Cursor

Defined in Graphics.Vty.Picture

Methods

rnf :: Cursor -> ()

Eq Cursor

Defined in Graphics.Vty.Picture

Methods

(==) :: Cursor -> Cursor -> Bool

(/=) :: Cursor -> Cursor -> Bool

data Background

A Picture has a background pattern. The background is either:

• ClearBackground, which shows the layer below or is blank if the bottom layer
• A character and a display attribute

If the display attribute used previously should be used for a background fill then use currentAttr for the background attribute.

Constructors

Background

Fields

• backgroundChar :: Char
• backgroundAttr :: Attr

ClearBackground

A ClearBackground is:

• the space character if there are remaining non-skip ops
• End of line if there are no remaining non-skip ops.

Instances

Show Background

Defined in Graphics.Vty.Picture

Methods

showsPrec :: Int -> Background -> ShowS

show :: Background -> String

showList :: [Background] -> ShowS

NFData Background

Defined in Graphics.Vty.Picture

Methods

rnf :: Background -> ()

Eq Background

Defined in Graphics.Vty.Picture

Methods

(==) :: Background -> Background -> Bool

(/=) :: Background -> Background -> Bool

emptyPicture :: Picture

A picture with no cursor, background or image layers.

addToTop :: Picture -> Image -> Picture

Add an Image as the top-most layer of a Picture.

addToBottom :: Picture -> Image -> Picture

Add an Image as the bottom-most layer of a Picture.

picForImage :: Image -> Picture

Create a picture from the given image. The picture will not have a displayed cursor and no background pattern (ClearBackground) will be used.

picForLayers :: [Image] -> Picture

Create a picture with the given layers, top-most first.

The picture will not have a displayed cursor and no background pattern (ClearBackgroun) will be used.

picImage :: Picture -> Image

Return the top-most Image layer for a picture. This is unsafe for Pictures without at least one layer.

This is provided for compatibility with applications that do not use more than a single layer.