pango-0.12.4: Binding to the Pango text rendering engine.

Portabilityportable (depends on GHC)
Stabilityprovisional
Maintainergtk2hs-users@lists.sourceforge.net
Safe HaskellNone

Graphics.Rendering.Pango.Cairo

Contents

Description

Pango specific functions to for redering with Cairo.

Cairo is a graphics library that supports vector graphics and image compositing that can be used with Pango. The functions in this module provide ways of rendering text in Cairo using Pango.

Synopsis

Global Cairo settings.

cairoFontMapGetDefault :: IO FontMapSource

Retrieve the default FontMap that contains a list of available fonts.

  • One purpose of creating an explicit FontMap is to set a different scaling factor between font sizes (in points, pt) and Cairo units (in pixels). The default is 96dpi (dots per inch) which corresponds to an average screen as output medium. A 10pt font will therefore scale to 10pt * (1/72 pt/inch) * (96 pixel/inch) = 13.3 pixel.

cairoFontMapSetResolution :: FontMap -> Double -> IO ()Source

Set the scaling factor between font size and Cairo units.

cairoFontMapGetResolution :: FontMap -> IO DoubleSource

Ask for the scaling factor between font size and Cairo units.

cairoCreateContext :: Maybe FontMap -> IO PangoContextSource

Create a PangoContext.

cairoContextSetResolution :: PangoContext -> Double -> IO ()Source

Set the scaling factor of the PangoContext.

cairoContextGetResolution :: PangoContext -> IO DoubleSource

Ask for the scaling factor of the PangoContext.

cairoContextSetFontOptions :: PangoContext -> FontOptions -> IO ()Source

Set Cairo font options.

  • Apply the given font options to the context. Values set through this functions override those that are set by updateContext.

cairoContextGetFontOptions :: PangoContext -> IO FontOptionsSource

Retrieve Cairo font options.

Functions for the Render monad.

setSourceColor :: Color -> Render ()Source

Sets the specified Color as the source color of the Render context.

updateContext :: PangoContext -> Render ()Source

Update a PangoContext with respect to changes in a Render environment.

createLayout :: String -> Render PangoLayoutSource

Create a PangoLayout within a Render context.

  • This is a convenience function that creates a new PangoContext within this Render context and creates a new PangoLayout. If the transformation or target surface of the Render context change, updateLayout has to be called on this layout.

updateLayout :: PangoLayout -> Render ()Source

Propagate changed to the Render context to a PangoLayout.

showGlyphString :: GlyphItem -> Render ()Source

Draw a glyph string.

  • The origin of the glyphs (the left edge of the baseline) will be drawn at the current point of the cairo context.

showLayoutLine :: LayoutLine -> Render ()Source

Draw a LayoutLine.

  • The origin of the glyphs (the left edge of the baseline) will be drawn at the current point of the cairo context.

showLayout :: PangoLayout -> Render ()Source

Draw a PangoLayout.

  • The top-left corner of the PangoLayout will be drawn at the current point of the cairo context.

glyphStringPath :: GlyphItem -> Render ()Source

Add the extent of a glyph string to the current path.

  • The origin of the glyphs (the left edge of the line) will be at the current point of the cairo context.

layoutLinePath :: LayoutLine -> Render ()Source

Add the extent of a layout line to the current path.

  • The origin of the glyphs (the left edge of the line) will be at the current point of the cairo context.

layoutPath :: PangoLayout -> Render ()Source

Add the layout to the current path.

  • Adds the top-left corner of the text to the current path. Afterwards, the path position is at the bottom-right corner of the PangoLayout.