FTGL-1.333: Portable TrueType font rendering for OpenGL using the Freetype2 librarySource codeContentsIndex
Graphics.Rendering.FTGL
Description
  • Author: Jefferson Heard (jefferson.r.heard at gmail.com)
  • Copyright 2008 Renaissance Computing Institute http://www.renci.org
  • License: GNU LGPL
  • Compatibility GHC (I could change the data declarations to not be empty and that would make it more generally compatible, I believe)
  • Description:

Use FreeType 2 Fonts in OpenGL. Requires the FTGL library and FreeType libraries. available at http://ftgl.wiki.sourceforge.net/ . The most important functions for everyday use are renderFont and the create*Font family of functions. To render a simple string inside OpenGL, assuming you have OpenGL initialized and a current pen color, all you need is: 

 do font <- createTextureFont "Font.ttf"
   setFontFaceSize font 24 72
   renderFont font "Hello world!"

Fonts are rendered so that a single point is an OpenGL unit, and a point is 1:72 of an inch.

Synopsis
fcreateBitmapFont :: CString -> IO Font
createBitmapFont :: String -> IO Font
fcreateBufferFont :: CString -> IO Font
createBufferFont :: String -> IO Font
fcreateOutlineFont :: CString -> IO Font
createOutlineFont :: String -> IO Font
fcreatePixmapFont :: CString -> IO Font
createPixmapFont :: String -> IO Font
fcreatePolygonFont :: CString -> IO Font
createPolygonFont :: String -> IO Font
fcreateTextureFont :: CString -> IO Font
createTextureFont :: String -> IO Font
fcreateExtrudeFont :: CString -> IO Font
createExtrudeFont :: String -> IO Font
createSimpleLayout :: IO Layout
setLayoutFont :: Layout -> Font -> IO ()
fgetLayoutFont :: Layout -> IO Font
setLayoutLineLength :: Layout -> CFloat -> IO ()
fgetLayoutLineLength :: Layout -> IO CFloat
getLayoutLineLength :: Layout -> IO Float
fsetLayoutAlignment :: Layout -> CInt -> IO ()
fgetLayoutAlignment :: Layout -> IO CInt
fsetLayoutLineSpacing :: Layout -> CFloat -> IO ()
setLayoutLineSpacing :: Layout -> Float -> IO ()
destroyFont :: Font -> IO ()
fattachFile :: Font -> CString -> IO ()
attachFile :: Font -> String -> IO ()
attachData :: Font -> Ptr () -> IO ()
fsetFontCharMap :: Font -> CInt -> IO ()
setCharMap :: Font -> CharMap -> IO ()
fgetFontCharMapCount :: Font -> IO CInt
getFontCharMapCount :: Font -> Int
fgetFontCharMapList :: Font -> IO (Ptr CInt)
fsetFontFaceSize :: Font -> CInt -> CInt -> IO CInt
setFontFaceSize :: Font -> Int -> Int -> IO CInt
fgetFontFaceSize :: Font -> IO CInt
getFontFaceSize :: Font -> IO Int
fsetFontDepth :: Font -> CFloat -> IO ()
setFontDepth :: Font -> Float -> IO ()
fsetFontOutset :: Font -> CFloat -> CFloat -> IO ()
setFontOutset :: Font -> Float -> Float -> IO ()
fgetFontBBox :: Font -> CString -> Int -> Ptr CFloat -> IO ()
getFontBBox :: Font -> String -> IO [Float]
fgetFontAscender :: Font -> CFloat
getFontAscender :: Font -> Float
fgetFontDescender :: Font -> CFloat
getFontDescender :: Font -> Float
fgetFontLineHeight :: Font -> CFloat
getFontLineHeight :: Font -> Float
fgetFontAdvance :: Font -> CString -> IO CFloat
getFontAdvance :: Font -> String -> IO Float
frenderFont :: Font -> CString -> CInt -> IO ()
renderFont :: Font -> String -> RenderMode -> IO ()
fgetFontError :: Font -> IO CInt
getFontError :: Font -> IO Int
destroyLayout :: Layout -> IO ()
frenderLayout :: Layout -> CString -> IO ()
fgetLayoutError :: Layout -> IO CInt
data RenderMode
= Front
| Back
| Side
| All
data TextAlignment
= AlignLeft
| AlignCenter
| AlignRight
| Justify
marshalRenderMode :: RenderMode -> CInt
marshalTextAlignment :: TextAlignment -> CInt
readTextAlignment :: CInt -> TextAlignment
data Glyph_Opaque
data Font_Opaque
data Layout_Opaque
type Glyph = Ptr Glyph_Opaque
type Font = Ptr Font_Opaque
type Layout = Ptr Layout_Opaque
data CharMap
= EncodingNone
| EncodingMSSymbol
| EncodingUnicode
| EncodingSJIS
| EncodingGB2312
| EncodingBig5
| EncodingWanSung
| EncodingJohab
| EncodingAdobeStandard
| EncodingAdobeExpert
| EncodingAdobeCustom
| EncodingAdobeLatin1
| EncodingOldLatin2
| EncodingAppleRoman
encodeTag :: Char -> Char -> Char -> Char -> CInt
Documentation
fcreateBitmapFont :: CString -> IO FontSource
createBitmapFont :: String -> IO FontSource
Create a bitmapped version of a TrueType font. Bitmapped versions will not | respond to matrix transformations, but rather must be transformed using the | raster positioning functions in OpenGL
fcreateBufferFont :: CString -> IO FontSource
createBufferFont :: String -> IO FontSource
Create a buffered version of a TrueType font. This stores the entirety of | a string in a texture, buffering it before rendering. Very fast if you | will be repeatedly rendering the same strings over and over.
fcreateOutlineFont :: CString -> IO FontSource
createOutlineFont :: String -> IO FontSource
Create an outline version of a TrueType font. This uses actual geometry | and will scale independently without loss of quality. Faster than polygons | but slower than texture or buffer fonts.
fcreatePixmapFont :: CString -> IO FontSource
createPixmapFont :: String -> IO FontSource
Create a pixmap version of a TrueType font. Higher quality than the bitmap | font without losing any performance. Use this if you don't mind using | set and get RasterPosition.
fcreatePolygonFont :: CString -> IO FontSource
createPolygonFont :: String -> IO FontSource
Create polygonal display list fonts. These scale independently without | losing quality, unlike texture or buffer fonts, but can be impractical | for large amounts of text because of the high number of polygons needed. | Additionally, they do not, unlike the textured fonts, create artifacts | within the square formed at the edge of each character.
fcreateTextureFont :: CString -> IO FontSource
createTextureFont :: String -> IO FontSource
Create textured display list fonts. These can scale somewhat well, | but lose quality quickly. They are much faster than polygonal fonts, | though, so are suitable for large quantities of text. Especially suited | well to text that changes with most frames, because it doesn't incur the | (normally helpful) overhead of buffering.
fcreateExtrudeFont :: CString -> IO FontSource
createExtrudeFont :: String -> IO FontSource
Create a 3D extruded font. This is the only way of creating 3D fonts | within FTGL. Could be fun to use a geometry shader to get different | effects by warping the otherwise square nature of the font. Polygonal. | Scales without losing quality. Slower than all other fonts.
createSimpleLayout :: IO LayoutSource
Create a simple layout
setLayoutFont :: Layout -> Font -> IO ()Source
Set the layout's font.
fgetLayoutFont :: Layout -> IO FontSource
setLayoutLineLength :: Layout -> CFloat -> IO ()Source

Get the embedded font from the Layout

Set the line length, I believe in OpenGL units, although I'm not sure.

fgetLayoutLineLength :: Layout -> IO CFloatSource
getLayoutLineLength :: Layout -> IO FloatSource
Get the line length in points (1:72in) of lines in the layout
fsetLayoutAlignment :: Layout -> CInt -> IO ()Source
fgetLayoutAlignment :: Layout -> IO CIntSource
Set the layout alignment
fsetLayoutLineSpacing :: Layout -> CFloat -> IO ()Source
Get the alignment of text in this layout.
setLayoutLineSpacing :: Layout -> Float -> IO ()Source
Set layout line spacing in OpenGL units.
destroyFont :: Font -> IO ()Source
Destroy a font
fattachFile :: Font -> CString -> IO ()Source
attachFile :: Font -> String -> IO ()Source
Attach a metadata file to a font.
attachData :: Font -> Ptr () -> IO ()Source
Attach some external data (often kerning) to the font
fsetFontCharMap :: Font -> CInt -> IO ()Source
Set the font's character map
setCharMap :: Font -> CharMap -> IO ()Source
fgetFontCharMapCount :: Font -> IO CIntSource
getFontCharMapCount :: Font -> IntSource
Get the number of characters loaded into the current charmap for the font.
fgetFontCharMapList :: Font -> IO (Ptr CInt)Source
fsetFontFaceSize :: Font -> CInt -> CInt -> IO CIntSource
Get the different character mappings available in this font.
setFontFaceSize :: Font -> Int -> Int -> IO CIntSource
fgetFontFaceSize :: Font -> IO CIntSource
getFontFaceSize :: Font -> IO IntSource
Get the current font face size in points.
fsetFontDepth :: Font -> CFloat -> IO ()Source
setFontDepth :: Font -> Float -> IO ()Source
fsetFontOutset :: Font -> CFloat -> CFloat -> IO ()Source
setFontOutset :: Font -> Float -> Float -> IO ()Source
fgetFontBBox :: Font -> CString -> Int -> Ptr CFloat -> IO ()Source
getFontBBox :: Font -> String -> IO [Float]Source
Get the text extents of a string as a list of (llx,lly,lly,urx,ury,urz)
fgetFontAscender :: Font -> CFloatSource
getFontAscender :: Font -> FloatSource
Get the global ascender height for the face.
fgetFontDescender :: Font -> CFloatSource
getFontDescender :: Font -> FloatSource
Gets the global descender height for the face.
fgetFontLineHeight :: Font -> CFloatSource
getFontLineHeight :: Font -> FloatSource
Gets the global line spacing for the face.
fgetFontAdvance :: Font -> CString -> IO CFloatSource
getFontAdvance :: Font -> String -> IO FloatSource
Get the horizontal span of a string of text using the current font. Input as the xcoord | in any translate operation
frenderFont :: Font -> CString -> CInt -> IO ()Source
renderFont :: Font -> String -> RenderMode -> IO ()Source
Render a string of text in the current font.
fgetFontError :: Font -> IO CIntSource
getFontError :: Font -> IO IntSource
Get any errors associated with loading a font. FIXME return should be a type, not an Int.
destroyLayout :: Layout -> IO ()Source
frenderLayout :: Layout -> CString -> IO ()Source
fgetLayoutError :: Layout -> IO CIntSource
Render a string of text within a layout.
data RenderMode Source

Get any errors associated with a layout.

Whether or not in polygonal or extrusion mode, the font will render equally front and back

Constructors
Front
Back
Side
All
data TextAlignment Source
In a Layout directed render, the layout mode of the text
Constructors
AlignLeft
AlignCenter
AlignRight
Justify
marshalRenderMode :: RenderMode -> CIntSource
marshalTextAlignment :: TextAlignment -> CIntSource
readTextAlignment :: CInt -> TextAlignmentSource
data Glyph_Opaque Source
An opaque type encapsulating a glyph in C. Currently the glyph functions are unimplemented in Haskell.
data Font_Opaque Source
An opaque type encapsulating a font in C.
data Layout_Opaque Source
An opaque type encapsulating a layout in C
type Glyph = Ptr Glyph_OpaqueSource
type Font = Ptr Font_OpaqueSource
type Layout = Ptr Layout_OpaqueSource
data CharMap Source
Constructors
EncodingNone
EncodingMSSymbol
EncodingUnicode
EncodingSJIS
EncodingGB2312
EncodingBig5
EncodingWanSung
EncodingJohab
EncodingAdobeStandard
EncodingAdobeExpert
EncodingAdobeCustom
EncodingAdobeLatin1
EncodingOldLatin2
EncodingAppleRoman
encodeTag :: Char -> Char -> Char -> Char -> CIntSource
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