Add font compression

1 files changed, 1318 insertions, 0 deletions

diff --git a/lib/Graphics/Fountainhead/TrueType.hs b/lib/Graphics/Fountainhead/TrueType.hs
new file mode 100644
index 0000000..0c15081
--- /dev/null
+++ b/lib/Graphics/Fountainhead/TrueType.hs
@@ -0,0 +1,1318 @@
+{- This Source Code Form is subject to the terms of the Mozilla Public License,
+   v. 2.0. If a copy of the MPL was not distributed with this file, You can
+   obtain one at https://mozilla.org/MPL/2.0/. -}
+
+{-# LANGUAGE DuplicateRecordFields #-}
+{-# LANGUAGE RecordWildCards #-}
+
+-- | Types representing a TrueType font.
+module Graphics.Fountainhead.TrueType
+    ( BArmStyle(..)
+    , BContrast(..)
+    , BFamilyType(..)
+    , BLetterform(..)
+    , BMidline(..)
+    , BProportion(..)
+    , BSerifStyle(..)
+    , BStrokeVariation(..)
+    , BWeight(..)
+    , BXHeight(..)
+    , CVTable(..)
+    , CmapSubtable(..)
+    , CmapTable(..)
+    , CmapEncoding(..)
+    , CmapFormat0Table(..)
+    , CmapFormat2Subheader(..)
+    , CmapFormat2Table(..)
+    , CmapFormat4Table(..)
+    , CmapFormat6Table(..)
+    , CmapGroup(..)
+    , CmapFormat8Table(..)
+    , CmapFormat10Table(..)
+    , CmapFormat12Table(..)
+    , CmapFormat13Table
+    , CmapFormat14Table(..)
+    , ComponentGlyphFlags(..)
+    , ComponentGlyphPartDescription(..)
+    , CompoundGlyphDefinition(..)
+    , DeviceRecord(..)
+    , FpgmTable(..)
+    , FontDirectionHint(..)
+    , FontDirectory(..)
+    , FontStyle(..)
+    , GASPRange(..)
+    , GASPTable(..)
+    , GlyfTable(..)
+    , GlyphArgument(..)
+    , GlyphCoordinate(..)
+    , GlyphDefinition(..)
+    , GlyphDescription(..)
+    , GlyphTransformationOption(..)
+    , HdmxTable(..)
+    , HeadTable(..)
+    , HheaTable(..)
+    , HmtxTable(..)
+    , IndexToLocFormat(..)
+    , LocaTable(..)
+    , LongHorMetric(..)
+    , MaxpTable(..)
+    , NameRecord(..)
+    , NameTable(..)
+    , OffsetSubtable(..)
+    , OpenMaxpTable(..)
+    , Os2BaseFields(..)
+    , Os2MicrosoftFields(..)
+    , Os2Table(..)
+    , Os2Version1Fields(..)
+    , Os2Version4Fields(..)
+    , Os2Version5Fields(..)
+    , OutlineFlag(..)
+    , Panose(..)
+    , PostFormat2Table(..)
+    , PostHeader(..)
+    , PostSubtable(..)
+    , PostTable(..)
+    , PrepTable(..)
+    , RangeGaspBehavior(..)
+    , SimpleGlyphDefinition(..)
+    , TableDirectory(..)
+    , TrueMaxpTable(..)
+    , UVSOffset(..)
+    , UVSMapping(..)
+    , UnicodeValueRange(..)
+    , VariationSelectorMap
+    , unLocaTable
+    , nameStringOffset
+    ) where
+
+import Data.ByteString (ByteString)
+import Data.Int (Int8, Int16)
+import Data.IntMap (IntMap)
+import Data.List.NonEmpty (NonEmpty(..))
+import Data.Time (LocalTime(..))
+import Data.Vector (Vector)
+import Data.Word (Word8, Word16, Word32)
+import Graphics.Fountainhead.Type (F2Dot14(..), Fixed32(..), FWord, UFWord)
+
+-- * Font directory
+
+data FontDirectory = FontDirectory
+    { offsetSubtable :: OffsetSubtable
+    , tableDirectory :: [TableDirectory]
+    } deriving (Eq, Show)
+
+data OffsetSubtable = OffsetSubtable
+    { scalerType :: Word32
+    , numTables :: Int
+    , searchRange :: Word16
+    , entrySelector :: Word16
+    , rangeShift :: Word16
+    } deriving (Eq, Show)
+
+data TableDirectory = TableDirectory
+    { tag :: ByteString
+    , checkSum :: Word32
+    , offset :: Int
+    , length :: Int
+    } deriving (Eq, Show)
+
+-- * Name table
+
+data NameTable = NameTable
+    { format :: Word16 -- ^ Format selector. Set to 0.
+    , nameRecord :: [NameRecord] -- ^ The name records array.
+    , variable :: [ByteString] -- ^ The character strings of the names.
+    } deriving (Eq, Show)
+
+data NameRecord = NameRecord
+    { platformID :: Word16 -- ^ Platform identifier code.
+    , platformSpecificID :: Word16 -- ^ Platform-specific encoding identifier.
+    , languageID :: Word16 -- ^  Language identifier.
+    , nameID :: Word16 -- ^ Name identifier.
+    , length :: Int -- ^ Name string length in bytes.
+    , offset :: Int -- ^ Offset.
+    } deriving (Eq, Show)
+
+nameStringOffset :: NameTable -> Word16
+nameStringOffset NameTable{..} =
+    let nameRecordSize = 12
+        precedingFieldsSize = 2 * 3
+     in nameRecordSize * fromIntegral (Prelude.length nameRecord) + precedingFieldsSize
+
+-- * 'cvt ' table
+
+newtype CVTable = CVTable [Int16]
+    deriving (Eq, Show)
+
+-- * Maximum profile table
+
+data TrueMaxpTable = TrueMaxpTable
+    { version :: Fixed32 -- ^ 0x00010000 (1.0).
+    , numGlyphs :: Word16 -- ^ The number of glyphs in the font.
+    , maxPoints :: Word16 -- ^ Points in non-compound glyph.
+    , maxContours :: Word16 -- ^ Contours in non-compound glyph.
+    , maxComponentPoints :: Word16 -- ^ Points in compound glyph.
+    , maxComponentContours :: Word16 -- ^ Contours in compound glyph.
+    , maxZones :: Word16 -- ^ Set to 2.
+    , maxTwilightPoints :: Word16 -- ^ Points used in Twilight Zone (Z0).
+    , maxStorage :: Word16 -- ^ Number of Storage Area locations.
+    , maxFunctionDefs :: Word16 -- ^ Number of FDEFs.
+    , maxInstructionDefs :: Word16 -- ^ Number of IDEFs.
+    , maxStackElements :: Word16 -- ^ Maximum stack depth.
+    , maxSizeOfInstructions :: Word16 -- ^ Byte count for glyph instructions.
+    , maxComponentElements :: Word16 -- ^ Number of glyphs referenced at top level.
+    , maxComponentDepth :: Word16 -- ^ Levels of recursion, set to 0 if font has only simple glyphs.
+    } deriving (Eq, Show)
+
+data OpenMaxpTable = OpenMaxpTable
+    { version :: Fixed32 -- ^ 0x00005000 (0.5).
+    , numGlyphs :: Word16 -- ^ The number of glyphs in the font.
+    } deriving (Eq, Show)
+
+data MaxpTable = OpenMaxp OpenMaxpTable | TrueMaxp TrueMaxpTable
+    deriving (Eq, Show)
+
+-- * Horizontal header table
+
+data HheaTable = HheaTable
+    { version :: Fixed32 -- ^ 0x00010000 (1.0).
+    , ascent :: FWord -- ^ Distance from baseline of highest ascender.
+    , descent :: FWord -- ^ Distance from baseline of lowest descender.
+    , lineGap :: FWord -- ^ Typographic line gap.
+    , advanceWidthMax :: UFWord -- ^ Must be consistent with horizontal metrics.
+    , minLeftSideBearing :: FWord -- ^ Must be consistent with horizontal metrics.
+    , minRightSideBearing :: FWord -- ^ Must be consistent with horizontal metrics.
+    , xMaxExtent :: FWord -- ^ max(lsb + (xMax-xMin)).
+    , caretSlopeRise :: Int16 -- ^ used to calculate the slope of the caret (rise/run) set to 1 for vertical caret.
+    , caretSlopeRun :: Int16 -- ^ 0 for vertical.
+    , caretOffset :: FWord -- ^ Set value to 0 for non-slanted fonts.
+    , metricDataFormat :: Int16 -- ^ 0 for current format.
+    , numOfLongHorMetrics :: Word16 -- ^ Number of advance widths in metrics table.
+    } deriving (Eq, Show)
+
+-- * Font header table
+
+data IndexToLocFormat
+    = ShortOffsetIndexToLocFormat
+    | LongOffsetIndexToLocFormat
+    deriving (Eq, Show)
+
+data HeadTable = HeadTable
+    { version :: Fixed32 -- ^ 0x00010000 if (version 1.0).
+    , fontRevision :: Fixed32 -- ^ Set by font manufacturer.
+    , checkSumAdjustment :: Word32 -- ^ To compute: set it to 0, calculate the checksum for the 'head' table and put it in the table directory, sum the entire font as a uint32_t, then store 0xB1B0AFBA - sum. (The checksum for the 'head' table will be wrong as a result. That is OK; do not reset it.)
+    , magicNumber :: Word32 -- ^ Set to 0x5F0F3CF5.
+    , flags :: Word16
+    , unitsPerEm :: Word16 -- ^ Range from 64 to 16384.
+    , created :: LocalTime -- ^ International date.
+    , modified :: LocalTime -- ^ International date.
+    , xMin :: Int16 -- ^ For all glyph bounding boxes.
+    , yMin :: Int16 -- ^ For all glyph bounding boxes.
+    , xMax :: Int16 -- ^ For all glyph bounding boxes.
+    , yMax :: Int16 -- ^ For all glyph bounding boxes.
+    , macStyle :: FontStyle
+    , lowestRecPPEM :: Word16 -- ^ Smallest readable size in pixels.
+    , fontDirectionHint :: FontDirectionHint -- ^ 0 Mixed directional glyphs.
+    , indexToLocFormat :: IndexToLocFormat -- ^ 0 for short offsets, 1 for long.
+    , glyphDataFormat :: Word16 -- ^ 0 for current format.
+    } deriving (Eq, Show)
+
+data FontStyle = FontStyle
+    { bold :: Bool
+    , italic :: Bool
+    , underline :: Bool
+    , outline :: Bool
+    , shadow :: Bool
+    , condensed :: Bool
+    , extended :: Bool
+    } deriving (Eq, Show)
+
+data FontDirectionHint
+    = MixedDirectionalGlyphs -- ^ 0. Mixed directional glyphs.
+    | StronglyLeftToRightGlyphs -- ^ 1. Only strongly left to right glyphs.
+    | LeftToRightGlyphsWithNeutrals -- ^ 2. Like 1 but also contains neutrals.
+    | StronglyRightToLeftGlyphs -- ^ -1. Only strongly right to left glyphs.
+    | RightToLeftGlyphsWithNeutrals -- ^ -2. Like -1 but also contains neutrals.
+    deriving (Eq, Show)
+
+data LocaTable
+    = ShortLocaTable (Vector Word16)
+    | LongLocaTable (Vector Word32)
+    deriving (Eq, Show)
+
+unLocaTable :: LocaTable -> Vector Word32
+unLocaTable (LongLocaTable values') = values'
+unLocaTable (ShortLocaTable values') = (* 2) . fromIntegral <$> values'
+
+-- * Horizontal metrics table
+
+data LongHorMetric = LongHorMetric
+    { advanceWidth :: Word16
+    , leftSideBearing :: Int16
+    } deriving (Eq, Show)
+
+data HmtxTable = HmtxTable
+    { hMetrics :: NonEmpty LongHorMetric
+    , leftSideBearing :: [Int16]
+    } deriving (Eq, Show)
+
+-- * Glyph name and PostScript font table
+
+data PostHeader = PostHeader
+    { format :: Fixed32 -- ^ Format of this table
+    , italicAngle :: Fixed32 -- ^ Italic angle in degrees
+    , underlinePosition :: Int16 -- ^ Underline position
+    , underlineThickness :: Int16 -- ^ Underline thickness
+    , isFixedPitch :: Word32 -- ^ Font is monospaced; set to 1 if the font is monospaced and 0 otherwise (N.B., to maintain compatibility with older versions of the TrueType spec, accept any non-zero value as meaning that the font is monospaced)
+    , minMemType42 :: Word32 -- ^ Minimum memory usage when a TrueType font is downloaded as a Type 42 font
+    , maxMemType42 :: Word32 -- ^ Maximum memory usage when a TrueType font is downloaded as a Type 42 font
+    , minMemType1 :: Word32 -- ^ Minimum memory usage when a TrueType font is downloaded as a Type 1 font
+    , maxMemType1 :: Word32 -- ^ Maximum memory usage when a TrueType font is downloaded as a Type 1 font
+    } deriving (Eq, Show)
+
+data PostFormat2Table = PostFormat2Table
+    { glyphNameIndex :: Vector Word16 -- ^ Ordinal number of this glyph in 'post' string tables. This is not an offset.
+    , names :: Vector ByteString
+    } deriving (Eq, Show)
+
+data PostSubtable
+    = None
+    | PostFormat2 PostFormat2Table
+    | PostFormat25 (Vector Int8)
+    | PostFormat4 (Vector Word16)
+    deriving (Eq, Show)
+
+data PostTable = PostTable
+    { postHeader :: PostHeader
+    , postSubtable :: PostSubtable
+    } deriving (Eq, Show)
+
+-- * Font program table
+
+newtype FpgmTable = FpgmTable (Vector Word8)
+    deriving (Eq, Show)
+
+-- * Prep table
+
+newtype PrepTable = PrepTable (Vector Word8)
+    deriving (Eq, Show)
+
+-- * Horizontal device metrics table
+
+data HdmxTable = HdmxTable
+    { format :: Int16 -- ^ Format version number.
+    , records :: [DeviceRecord]
+    } deriving (Eq, Show)
+
+data DeviceRecord = DeviceRecord
+    { pixelSize :: Word8 -- ^ Pixel size for following widths.
+    , maximumWidth :: Word8 -- ^ Maximum width.
+    , widths :: Vector Word8 -- ^ Widths.
+    } deriving (Eq, Show)
+
+-- * Glyph outline table
+
+data GlyphDescription = GlyphDescription
+    { numberOfContours :: Int
+    , xMin :: Int16 -- ^ Minimum x for coordinate data.
+    , yMin :: Int16 -- ^ Minimum y for coordinate data.
+    , xMax :: Int16 -- ^ Maximum x for coordinate data.
+    , yMax :: Int16 -- ^ Maximum y for coordinate data.
+    , definition :: GlyphDefinition
+    } deriving (Eq, Show)
+
+data GlyphArgument
+    = GlyphInt16Argument Int16
+    | GlyphWord16Argument Word16
+    | GlyphInt8Argument Int8
+    | GlyphWord8Argument Word8
+    deriving (Eq, Show)
+
+data GlyphTransformationOption
+    = GlyphNoScale
+    | GlyphScale F2Dot14
+    | GlyphXyScale F2Dot14 F2Dot14
+    | Glyph2By2Scale F2Dot14 F2Dot14 F2Dot14 F2Dot14
+    deriving (Eq, Show)
+
+data SimpleGlyphDefinition = SimpleGlyphDefinition
+    -- | Array of last points of each contour; n is the number of contours;
+    -- array entries are point indices.
+    { endPtsOfContours :: Vector Word16
+    -- | Array of instructions for this glyph.
+    , instructions :: Vector Word8
+    -- Array of flags.
+    , flags :: Vector OutlineFlag
+    -- | Array of coordinates; the first is relative to (0,0), others are
+    -- relative to previous point.
+    , coordinates :: Vector GlyphCoordinate
+    } deriving (Eq, Show)
+
+data CompoundGlyphDefinition = CompoundGlyphDefinition
+    { components :: Vector ComponentGlyphPartDescription
+    , instructions :: Vector Word8
+    } deriving (Eq, Show)
+
+data GlyphDefinition
+    = SimpleGlyph SimpleGlyphDefinition
+    | CompoundGlyph CompoundGlyphDefinition
+    deriving (Eq, Show)
+
+data ComponentGlyphFlags = ComponentGlyphFlags
+    { roundXyToGrid :: Bool
+    , weHaveInstructions :: Bool
+    , useMyMetrics :: Bool
+    , overlapCompound :: Bool
+    } deriving (Eq, Show)
+
+data GlyphCoordinate = GlyphCoordinate
+    { coordinateX :: Int16
+    , coordinateY :: Int16
+    } deriving (Eq, Show)
+
+instance Semigroup GlyphCoordinate
+  where
+    lhs <> rhs =
+        let GlyphCoordinate{ coordinateX = lhX, coordinateY = lhY } = lhs
+            GlyphCoordinate{ coordinateX = rhX, coordinateY = rhY } = rhs
+         in GlyphCoordinate{ coordinateX = lhX + rhX, coordinateY = lhY + rhY }
+
+instance Monoid GlyphCoordinate
+  where
+    mempty = GlyphCoordinate 0 0
+
+data ComponentGlyphPartDescription = ComponentGlyphPartDescription
+    { flags :: ComponentGlyphFlags
+    , glyphIndex :: Word16
+    , argument1 :: GlyphArgument
+    , argument2 :: GlyphArgument
+    , transformationOption :: GlyphTransformationOption
+    } deriving (Eq, Show)
+
+-- * Glyph outline table
+
+data OutlineFlag = OutlineFlag
+    { onCurve :: Bool
+    , xShortVector :: Bool
+    , yShortVector :: Bool
+    , repeat :: Word8
+    , thisXIsSame :: Bool
+    , thisYIsSame :: Bool
+    } deriving (Eq, Show)
+
+newtype GlyfTable = GlyfTable (Vector GlyphDescription)
+    deriving (Eq, Show)
+
+-- 'cmap' table
+
+-- | Character to glyph mapping table.
+data CmapTable = CmapTable
+    { version :: Word16 -- ^ Version number is zero.
+    -- | Encodings with an offset into subtables map.
+    , encodings :: [CmapEncoding]
+    -- ^ The key into the map is the offset in the 'CmapEncoding's.
+    , subtables :: IntMap CmapSubtable
+    } deriving (Eq, Show)
+
+data CmapEncoding = CmapEncoding
+    { platformID :: Word16 -- ^ Platform identifier
+    , platformSpecificID :: Word16 -- ^ Platform-specific encoding identifier.
+    , offset :: Word32 -- ^ Offst of the mapping table.
+    } deriving (Eq, Show)
+
+data CmapFormat0Table = CmapFormat0Table
+    { language :: Word16 -- ^ Language code.
+    , glyphIndexArray :: Vector Word8 -- ^ An array that maps character codes to glyph index values.
+    } deriving (Eq, Show)
+
+data CmapFormat2Subheader = CmapFormat2Subheader
+    { firstCode :: Word16
+    , entryCount :: Word16
+    , idDelta :: Int16
+    , idRangeOffset :: Word16
+    } deriving (Eq, Show)
+
+data CmapFormat2Table = CmapFormat2Table
+    { language :: Word16 -- ^ Language code.
+    , subHeaderKeys :: Vector Word16 -- ^ Array that maps high bytes to subHeaders: value is index * 8.
+    , subHeaders :: Vector CmapFormat2Subheader -- ^ Variable length array of subHeader structures.
+    , glyphIndexArray :: Vector Word16 -- ^ Variable length array containing subarrays.
+    } deriving (Eq, Show)
+
+data CmapFormat4Table = CmapFormat4Table
+    { language :: Word16 -- ^ Language code.
+    , searchRange :: Word16 -- ^ 2 * (2**FLOOR(log2(segCount))).
+    , entrySelector :: Word16 -- ^ log2(searchRange/2).
+    , rangeShift :: Word16 -- ^ (2 * segCount) - searchRange.
+    , endCode :: Vector Word16 -- ^ Ending character code for each segment, last = 0xFFFF.
+    , startCode :: Vector Word16 -- ^ Starting character code for each segment.
+    , idDelta :: Vector Word16 -- ^ Delta for all character codes in segment.
+    , idRangeOffset :: Vector Word16 -- ^ Offset in bytes to glyph indexArray, or 0.
+    , glyphIndexArray :: Vector Word16 -- ^ Glyph index array.
+    } deriving (Eq, Show)
+
+data CmapFormat6Table = CmapFormat6Table
+    { language :: Word16 -- ^ Language code.
+    , firstCode :: Word16 -- ^ First character code of subrange.
+    , glyphIndexArray :: Vector Word16 -- ^ Array of glyph index values for character codes in the range
+    } deriving (Eq, Show)
+
+data CmapGroup = CmapGroup
+    -- | First character code in this group; note that if this group is for one
+    -- or more 16-bit character codes (which is determined from the is32 array),
+    -- this 32-bit value will have the high 16-bits set to zero.
+    { startCharCode :: Word32
+    -- | Last character code in this group; same condition as listed above for
+    -- the startCharCode.
+    , endCharCode :: Word32
+    -- | Glyph index corresponding to the starting character code.
+    , startGlyphCode :: Word32
+    } deriving (Eq, Show)
+
+data CmapFormat8Table = CmapFormat8Table
+    { language :: Word32 -- ^ Language code.
+    -- | Tightly packed array of bits (8K bytes total) indicating whether the
+    -- particular 16-bit (index) value is the start of a 32-bit character code.
+    , is32 :: [Word8]
+    -- | Word32 Number of groupings which follow.
+    , groups :: Vector CmapGroup
+    } deriving (Eq, Show)
+
+data CmapFormat10Table = CmapFormat10Table
+    { language :: Word32 -- ^ Language code.
+    , startCharCode :: Word32 -- ^ First character code covered.
+    , numChars :: Word32 -- ^ Number of character codes covered.
+    , glyphs :: Vector Word16 -- ^ Array of glyph indices for the character codes covered.
+    } deriving (Eq, Show)
+
+data CmapFormat12Table = CmapFormat12Table
+    { language :: Word32 -- ^ Language code.
+    , groups :: Vector CmapGroup
+    } deriving (Eq, Show)
+
+type CmapFormat13Table = CmapFormat12Table
+
+newtype CmapFormat14Table = CmapFormat14Table
+    { varSelectorRecords :: VariationSelectorMap
+    } deriving (Eq, Show)
+
+data CmapSubtable
+    = CmapFormat0 CmapFormat0Table
+    | CmapFormat2 CmapFormat2Table
+    | CmapFormat4 CmapFormat4Table
+    | CmapFormat6 CmapFormat6Table
+    | CmapFormat8 CmapFormat8Table
+    | CmapFormat10 CmapFormat10Table
+    | CmapFormat12 CmapFormat12Table
+    | CmapFormat13 CmapFormat13Table
+    | CmapFormat14 CmapFormat14Table
+    deriving (Eq, Show)
+
+data UVSOffset a b = DefaultUVSOffset Word32 a | NonDefaultUVSOffset Word32 b
+    deriving (Eq, Show)
+
+data UVSMapping = UVSMapping
+    { unicodeValue :: Word32 -- ^ Base Unicode value of the UVS.
+    , glyphID :: Word16 -- ^ Glyph ID of the UVS.
+    } deriving (Eq, Show)
+
+data UnicodeValueRange = UnicodeValueRange
+    { startUnicodeValue :: Word32 -- ^ First value in this range.
+    , additionalCount :: Word8 -- ^ Number of additional values in this range.
+    } deriving (Eq, Show)
+
+-- | Mapping from variation selector record offsets to the record data.
+type VariationSelectorMap = IntMap
+    (NonEmpty (UVSOffset (Vector UnicodeValueRange) (Vector UVSMapping)))
+
+-- * OS/2 table
+
+data Os2Table
+    = Os2Version0 Os2BaseFields (Maybe Os2MicrosoftFields)
+    | Os2Version1 Os2BaseFields Os2MicrosoftFields Os2Version1Fields
+    | Os2Version2 Os2BaseFields Os2MicrosoftFields Os2Version4Fields
+    | Os2Version3 Os2BaseFields Os2MicrosoftFields Os2Version4Fields
+    | Os2Version4 Os2BaseFields Os2MicrosoftFields Os2Version4Fields
+    | Os2Version5 Os2BaseFields Os2MicrosoftFields Os2Version5Fields
+    deriving (Eq, Show)
+
+data Os2Version1Fields = Os2Version1Fields
+    { ulCodePageRange1 :: Word32
+    , ulCodePageRange2 :: Word32
+    } deriving (Eq, Show)
+
+data Os2MicrosoftFields = Os2MicrosoftFields
+    { sTypoAscender :: Int16
+    , sTypoDescender :: Int16
+    , sTypoLineGap :: Int16
+    , usWinAscent :: Word16
+    , usWinDescent :: Word16
+    } deriving (Eq, Show)
+
+data Os2Version4Fields = Os2Version4Fields
+    { ulCodePageRange1 :: Word32
+    , ulCodePageRange2 :: Word32
+    , sxHeight :: Int16
+    , sCapHeight :: Int16
+    , usDefaultChar :: Word16
+    , usBreakChar :: Word16
+    , usMaxContext :: Word16
+    } deriving (Eq, Show)
+
+data Os2Version5Fields = Os2Version5Fields
+    { ulCodePageRange1 :: Word32
+    , ulCodePageRange2 :: Word32
+    , sxHeight :: Int16
+    , sCapHeight :: Int16
+    , usDefaultChar :: Word16
+    , usBreakChar :: Word16
+    , usMaxContext :: Word16
+    , usLowerOpticalPointSize :: Word16
+    , usUpperOpticalPointSize :: Word16
+    } deriving (Eq, Show)
+
+data Os2BaseFields = Os2BaseFields
+    { version :: Word16 -- ^ Table version number (set to 0).
+    -- | Average weighted advance width of lower case letters and space.
+    , xAvgCharWidth :: Int16
+    -- | Visual weight (degree of blackness or thickness) of stroke in glyphs.
+    , usWeightClass :: Word16
+    -- | Relative change from the normal aspect ratio (width to height ratio)
+    -- as specified by a font designer for the glyphs in the font.
+    , usWidthClass :: Word16
+    -- | Characteristics and properties of this font (set undefined bits to
+    -- zero).
+    , fsType :: Int16
+    -- | Recommended horizontal size in pixels for subscripts.
+    , ySubscriptXSize :: Int16
+    -- | Recommended vertical size in pixels for subscripts.
+    , ySubscriptYSize :: Int16
+    -- | Recommended horizontal offset for subscripts.
+    , ySubscriptXOffset :: Int16
+    -- | Recommended vertical offset form the baseline for subscripts.
+    , ySubscriptYOffset :: Int16
+    -- | Recommended horizontal size in pixels for superscripts.
+    , ySuperscriptXSize :: Int16
+    -- | Recommended vertical size in pixels for superscripts.
+    , ySuperscriptYSize :: Int16
+    -- | Recommended horizontal offset for superscripts.
+    , ySuperscriptXOffset :: Int16
+    -- | Recommended vertical offset from the baseline for superscripts.
+    , ySuperscriptYOffset :: Int16
+    -- | Width of the strikeout stroke.
+    , yStrikeoutSize :: Int16
+    -- | Position of the strikeout stroke relative to the baseline.
+    , yStrikeoutPosition :: Int16
+    -- ^ Classification of font-family design.
+    , sFamilyClass :: Int16
+    -- | 10 byte series of number used to describe the visual characteristics
+    -- of a given typeface.
+    , panose :: Panose
+    -- | Field is split into two bit fields of 96 and 36 bits each. The low 96
+    -- bits are used to specify the Unicode blocks encompassed by the font file.
+    -- The high 32 bits are used to specify the character or script sets covered
+    -- by the font file. Bit assignments are pending. Set to 0.
+    , ulUnicodeRange :: Vector Word32
+    -- | Four character identifier for the font vendor.
+    , achVendID :: Vector Int8
+    -- | 2-byte bit field containing information concerning the nature of the
+    -- font patterns.
+    , fsSelection :: Word16
+    -- | The minimum Unicode index in this font.
+    , fsFirstCharIndex :: Word16
+    -- | The maximum Unicode index in this font.
+    , fsLastCharIndex :: Word16
+    } deriving (Eq, Show)
+
+data Panose = Panose
+    { bFamilyType :: BFamilyType
+    , bSerifStyle :: BSerifStyle
+    , bWeight :: BWeight
+    , bProportion :: BProportion
+    , bContrast :: BContrast
+    , bStrokeVariation :: BStrokeVariation
+    , bArmStyle :: BArmStyle
+    , bLetterform :: BLetterform
+    , bMidline :: BMidline
+    , bXHeight :: BXHeight
+    } deriving (Eq, Show)
+
+data BFamilyType
+    = AnyFamilyType
+    | NoFitFamilyType
+    | TextAndDisplayFamilyType
+    | ScriptFamilyType
+    | DecorativeFamilyType
+    | PictorialFamilyType
+    deriving Eq
+
+instance Show BFamilyType
+  where
+    show AnyFamilyType = "Any"
+    show NoFitFamilyType = "No Fit"
+    show TextAndDisplayFamilyType = "Text and Display"
+    show ScriptFamilyType = "Script"
+    show DecorativeFamilyType = "Decorative"
+    show PictorialFamilyType = "Pictorial"
+
+instance Enum BFamilyType
+  where
+    toEnum 0 = AnyFamilyType
+    toEnum 1 = NoFitFamilyType
+    toEnum 2 = TextAndDisplayFamilyType
+    toEnum 3 = ScriptFamilyType
+    toEnum 4 = DecorativeFamilyType
+    toEnum 5 = PictorialFamilyType
+    toEnum _ = error "Unknown family type"
+    fromEnum AnyFamilyType = 0
+    fromEnum NoFitFamilyType = 1
+    fromEnum TextAndDisplayFamilyType = 2
+    fromEnum ScriptFamilyType = 3
+    fromEnum DecorativeFamilyType = 4
+    fromEnum PictorialFamilyType = 5
+
+data BSerifStyle
+    = AnySerifStyle
+    | NoFitSerifStyle
+    | CoveSerifStyle
+    | ObtuseCoveSerifStyle
+    | SquareCoveSerifStyle
+    | ObtuseSquareCoveSerifStyle
+    | SquareSerifStyle
+    | ThinSerifStyle
+    | BoneSerifStyle
+    | ExaggeratedSerifStyle
+    | TriangleSerifStyle
+    | NormalSansSerifStyle
+    | ObtuseSansSerifStyle
+    | PerpSansSerifStyle
+    | FlaredSerifStyle
+    | RoundedSerifStyle
+    deriving Eq
+
+instance Show BSerifStyle
+  where
+    show AnySerifStyle = "Any"
+    show NoFitSerifStyle = "No Fit"
+    show CoveSerifStyle = "Cove"
+    show ObtuseCoveSerifStyle = "Obtuse Cove"
+    show SquareCoveSerifStyle = "Square Cove"
+    show ObtuseSquareCoveSerifStyle = "Obtuse Square Cove"
+    show SquareSerifStyle = "Square"
+    show ThinSerifStyle = "Thin"
+    show BoneSerifStyle = "Bone"
+    show ExaggeratedSerifStyle = "Exaggerated"
+    show TriangleSerifStyle = "Triangle"
+    show NormalSansSerifStyle = "Normal Sans"
+    show ObtuseSansSerifStyle = "Obtuse Sans"
+    show PerpSansSerifStyle = "Perp Sans"
+    show FlaredSerifStyle = "Flared"
+    show RoundedSerifStyle = "Rounded"
+
+instance Enum BSerifStyle
+  where
+    toEnum 0 = AnySerifStyle
+    toEnum 1 = NoFitSerifStyle
+    toEnum 2 = CoveSerifStyle
+    toEnum 3 = ObtuseCoveSerifStyle
+    toEnum 4 = SquareCoveSerifStyle
+    toEnum 5 = ObtuseSquareCoveSerifStyle
+    toEnum 6 = SquareSerifStyle
+    toEnum 7 = ThinSerifStyle
+    toEnum 8 = BoneSerifStyle
+    toEnum 9 = ExaggeratedSerifStyle
+    toEnum 10 = TriangleSerifStyle
+    toEnum 11 = NormalSansSerifStyle
+    toEnum 12 = ObtuseSansSerifStyle
+    toEnum 13 = PerpSansSerifStyle
+    toEnum 14 = FlaredSerifStyle
+    toEnum 15 = RoundedSerifStyle
+    toEnum _ = error "Unknown serif type"
+    fromEnum AnySerifStyle = 0
+    fromEnum NoFitSerifStyle = 1
+    fromEnum CoveSerifStyle = 2
+    fromEnum ObtuseCoveSerifStyle = 3
+    fromEnum SquareCoveSerifStyle = 4
+    fromEnum ObtuseSquareCoveSerifStyle = 5
+    fromEnum SquareSerifStyle = 6
+    fromEnum ThinSerifStyle = 7
+    fromEnum BoneSerifStyle = 8
+    fromEnum ExaggeratedSerifStyle = 9
+    fromEnum TriangleSerifStyle = 10
+    fromEnum NormalSansSerifStyle = 11
+    fromEnum ObtuseSansSerifStyle = 12
+    fromEnum PerpSansSerifStyle = 13
+    fromEnum FlaredSerifStyle = 14
+    fromEnum RoundedSerifStyle = 15
+
+data BWeight
+    = AnyWeight
+    | NoFitWeight
+    | VeryLightWeight
+    | LightWeight
+    | ThinWeight
+    | BookWeight
+    | MediumWeight
+    | DemiWeight
+    | BoldWeight
+    | HeavyWeight
+    | BlackWeight
+    | NordWeight
+    deriving Eq
+
+instance Show BWeight
+  where
+    show AnyWeight = "Any"
+    show NoFitWeight = "No Fit"
+    show VeryLightWeight = "Very Light"
+    show LightWeight = "Light"
+    show ThinWeight = "Thin"
+    show BookWeight = "Book"
+    show MediumWeight = "Medium"
+    show DemiWeight = "Demi"
+    show BoldWeight = "Bold"
+    show HeavyWeight = "Heavy"
+    show BlackWeight = "Black"
+    show NordWeight = "Nord"
+
+instance Enum BWeight
+  where
+    fromEnum AnyWeight = 0
+    fromEnum NoFitWeight = 1
+    fromEnum VeryLightWeight = 2
+    fromEnum LightWeight = 3
+    fromEnum ThinWeight = 4
+    fromEnum BookWeight = 5
+    fromEnum MediumWeight = 6
+    fromEnum DemiWeight = 7
+    fromEnum BoldWeight = 8
+    fromEnum HeavyWeight = 9
+    fromEnum BlackWeight = 10
+    fromEnum NordWeight = 11
+    toEnum 0 = AnyWeight
+    toEnum 1 = NoFitWeight
+    toEnum 2 = VeryLightWeight
+    toEnum 3 = LightWeight
+    toEnum 4 = ThinWeight
+    toEnum 5 = BookWeight
+    toEnum 6 = MediumWeight
+    toEnum 7 = DemiWeight
+    toEnum 8 = BoldWeight
+    toEnum 9 = HeavyWeight
+    toEnum 10 = BlackWeight
+    toEnum 11 = NordWeight
+    toEnum _ = error "Unknown weight"
+
+data BProportion
+    = AnyProportion
+    | NoFitProportion
+    | OldStyleProportion
+    | ModernProportion
+    | EvenWidthProportion
+    | ExpandedProportion
+    | CondensedProportion
+    | VeryExpandedProportion
+    | VeryCondensedProportion
+    | MonospacedProportion
+    deriving Eq
+
+instance Show BProportion
+  where
+    show AnyProportion = "Any"
+    show NoFitProportion = "No Fit"
+    show OldStyleProportion = "Old Style"
+    show ModernProportion = "Modern"
+    show EvenWidthProportion = "Even Width"
+    show ExpandedProportion = "Expanded"
+    show CondensedProportion = "Condensed"
+    show VeryExpandedProportion = "Very Expanded"
+    show VeryCondensedProportion = "Very Condensed"
+    show MonospacedProportion = "Monospaced"
+
+instance Enum BProportion
+  where
+    fromEnum AnyProportion = 0
+    fromEnum NoFitProportion = 1
+    fromEnum OldStyleProportion = 2
+    fromEnum ModernProportion = 3
+    fromEnum EvenWidthProportion = 4
+    fromEnum ExpandedProportion = 5
+    fromEnum CondensedProportion = 6
+    fromEnum VeryExpandedProportion = 7
+    fromEnum VeryCondensedProportion = 8
+    fromEnum MonospacedProportion = 9
+    toEnum 0 = AnyProportion
+    toEnum 1 = NoFitProportion
+    toEnum 2 = OldStyleProportion
+    toEnum 3 = ModernProportion
+    toEnum 4 = EvenWidthProportion
+    toEnum 5 = ExpandedProportion
+    toEnum 6 = CondensedProportion
+    toEnum 7 = VeryExpandedProportion
+    toEnum 8 = VeryCondensedProportion
+    toEnum 9 = MonospacedProportion
+    toEnum _ = error "Unknown proportion"
+
+data BContrast
+    = AnyContrast
+    | NoFitContrast
+    | NoneContrast
+    | VeryLowContrast
+    | LowContrast
+    | MediumLowContrast
+    | MediumContrast
+    | MediumHighContrast
+    | HighContrast
+    | VeryHighContrast
+    deriving Eq
+
+instance Show BContrast
+  where
+    show AnyContrast = "Any"
+    show NoFitContrast = "No Fit"
+    show NoneContrast = "None"
+    show VeryLowContrast = "Very Low"
+    show LowContrast = "Low"
+    show MediumLowContrast = "Medium Low"
+    show MediumContrast = "Medium"
+    show MediumHighContrast = "Medium High"
+    show HighContrast = "High"
+    show VeryHighContrast = "Very High"
+
+instance Enum BContrast
+  where
+    fromEnum AnyContrast = 0
+    fromEnum NoFitContrast = 1
+    fromEnum NoneContrast = 2
+    fromEnum VeryLowContrast = 3
+    fromEnum LowContrast = 4
+    fromEnum MediumLowContrast = 5
+    fromEnum MediumContrast = 6
+    fromEnum MediumHighContrast = 7
+    fromEnum HighContrast = 8
+    fromEnum VeryHighContrast = 9
+    toEnum 0 = AnyContrast
+    toEnum 1 = NoFitContrast
+    toEnum 2 = NoneContrast
+    toEnum 3 = VeryLowContrast
+    toEnum 4 = LowContrast
+    toEnum 5 = MediumLowContrast
+    toEnum 6 = MediumContrast
+    toEnum 7 = MediumHighContrast
+    toEnum 8 = HighContrast
+    toEnum 9 = VeryHighContrast
+    toEnum _ = error "Unknown contrast"
+
+data BStrokeVariation
+    = AnyStrokeVariation
+    | NoFitStrokeVariation
+    | GradualDiagonalStrokeVariation
+    | GradualTransitionalStrokeVariation
+    | GradualVerticalStrokeVariation
+    | GradualHorizontalStrokeVariation
+    | RapidVerticalStrokeVariation
+    | RapidHorizontalStrokeVariation
+    | InstantVerticalStrokeVariation
+    deriving Eq
+
+instance Show BStrokeVariation
+  where
+    show AnyStrokeVariation = "Any"
+    show NoFitStrokeVariation = "No Fit"
+    show GradualDiagonalStrokeVariation = "Gradual/Diagonal"
+    show GradualTransitionalStrokeVariation = "Gradual/Transitional"
+    show GradualVerticalStrokeVariation = "Gradual/Vertical"
+    show GradualHorizontalStrokeVariation = "Gradual/Horizontal"
+    show RapidVerticalStrokeVariation = "Rapid/Vertical"
+    show RapidHorizontalStrokeVariation = "Rapid/Horizontal"
+    show InstantVerticalStrokeVariation = "Instant/Vertical"
+
+instance Enum BStrokeVariation
+  where
+    fromEnum AnyStrokeVariation = 0
+    fromEnum NoFitStrokeVariation = 1
+    fromEnum GradualDiagonalStrokeVariation = 2
+    fromEnum GradualTransitionalStrokeVariation = 3
+    fromEnum GradualVerticalStrokeVariation = 4
+    fromEnum GradualHorizontalStrokeVariation = 5
+    fromEnum RapidVerticalStrokeVariation = 6
+    fromEnum RapidHorizontalStrokeVariation = 7
+    fromEnum InstantVerticalStrokeVariation = 8
+    toEnum 0 = AnyStrokeVariation
+    toEnum 1 = NoFitStrokeVariation
+    toEnum 2 = GradualDiagonalStrokeVariation
+    toEnum 3 = GradualTransitionalStrokeVariation
+    toEnum 4 = GradualVerticalStrokeVariation
+    toEnum 5 = GradualHorizontalStrokeVariation
+    toEnum 6 = RapidVerticalStrokeVariation
+    toEnum 7 = RapidHorizontalStrokeVariation
+    toEnum 8 = InstantVerticalStrokeVariation
+    toEnum _ = error "Unknown stroke variation"
+
+data BArmStyle
+    = AnyArmStyle
+    | NoFitArmStyle
+    | StraightArmsHorizontalArmStyle
+    | StraightArmsWedgeArmStyle
+    | StraightArmsVerticalArmStyle
+    | StraightArmsSingleSerifArmStyle
+    | StraightArmsDoubleSerifArmStyle
+    | NonStraightArmsHorizontalArmStyle
+    | NonStraightArmsWedgeArmStyle
+    | NonStraightArmsVerticalArmStyle
+    | NonStraightArmsSingleSerifArmStyle
+    | NonStraightArmsDoubleSerifArmStyle
+    deriving Eq
+
+instance Show BArmStyle
+  where
+    show AnyArmStyle = "Any"
+    show NoFitArmStyle = "No Fit"
+    show StraightArmsHorizontalArmStyle = "Straight Arms/Horizontal"
+    show StraightArmsWedgeArmStyle = "Straight Arms/Wedge"
+    show StraightArmsVerticalArmStyle = "Straight Arms/Vertical"
+    show StraightArmsSingleSerifArmStyle = "Straight Arms/Single Serif"
+    show StraightArmsDoubleSerifArmStyle = "Straight Arms/Double Serif"
+    show NonStraightArmsHorizontalArmStyle = "Non-Straight Arms/Horizontal"
+    show NonStraightArmsWedgeArmStyle = "Non-Straight Arms/Wedge"
+    show NonStraightArmsVerticalArmStyle = "Non-Straight Arms/Vertical"
+    show NonStraightArmsSingleSerifArmStyle = "Non-Straight Arms/Single Serif"
+    show NonStraightArmsDoubleSerifArmStyle = "Non-Straight Arms/Double Serif"
+
+instance Enum BArmStyle
+  where
+    fromEnum AnyArmStyle = 0
+    fromEnum NoFitArmStyle = 1
+    fromEnum StraightArmsHorizontalArmStyle = 2
+    fromEnum StraightArmsWedgeArmStyle = 3
+    fromEnum StraightArmsVerticalArmStyle = 4
+    fromEnum StraightArmsSingleSerifArmStyle = 5
+    fromEnum StraightArmsDoubleSerifArmStyle = 6
+    fromEnum NonStraightArmsHorizontalArmStyle = 7
+    fromEnum NonStraightArmsWedgeArmStyle = 8
+    fromEnum NonStraightArmsVerticalArmStyle = 9
+    fromEnum NonStraightArmsSingleSerifArmStyle = 10
+    fromEnum NonStraightArmsDoubleSerifArmStyle = 11
+    toEnum 0 = AnyArmStyle
+    toEnum 1 = NoFitArmStyle
+    toEnum 2 = StraightArmsHorizontalArmStyle
+    toEnum 3 = StraightArmsWedgeArmStyle
+    toEnum 4 = StraightArmsVerticalArmStyle
+    toEnum 5 = StraightArmsSingleSerifArmStyle
+    toEnum 6 = StraightArmsDoubleSerifArmStyle
+    toEnum 7 = NonStraightArmsHorizontalArmStyle
+    toEnum 8 = NonStraightArmsWedgeArmStyle
+    toEnum 9 = NonStraightArmsVerticalArmStyle
+    toEnum 10 = NonStraightArmsSingleSerifArmStyle
+    toEnum 11 = NonStraightArmsDoubleSerifArmStyle
+    toEnum _ = error "Unknown arm style"
+
+data BLetterform
+    = AnyLetterform
+    | NoFitLetterform
+    | NormalContactLetterform
+    | NormalWeightedLetterform
+    | NormalBoxedLetterform
+    | NormalFlattenedLetterform
+    | NormalRoundedLetterform
+    | NormalOffCenterLetterform
+    | NormalSquareLetterform
+    | ObliqueContactLetterform
+    | ObliqueWeightedLetterform
+    | ObliqueBoxedLetterform
+    | ObliqueFlattenedLetterform
+    | ObliqueRoundedLetterform
+    | ObliqueOffCenterLetterform
+    | ObliqueSquareLetterform
+    deriving Eq
+
+instance Show BLetterform
+  where
+    show AnyLetterform = "Any"
+    show NoFitLetterform = "No Fit"
+    show NormalContactLetterform = "Normal/Contact"
+    show NormalWeightedLetterform = "Normal/Weighted"
+    show NormalBoxedLetterform = "Normal/Boxed"
+    show NormalFlattenedLetterform = "Normal/Flattened"
+    show NormalRoundedLetterform = "Normal/Rounded"
+    show NormalOffCenterLetterform = "Normal/Off Center"
+    show NormalSquareLetterform = "Normal/Square"
+    show ObliqueContactLetterform = "Oblique/Contact"
+    show ObliqueWeightedLetterform = "Oblique/Weighted"
+    show ObliqueBoxedLetterform = "Oblique/Boxed"
+    show ObliqueFlattenedLetterform = "Oblique/Flattened"
+    show ObliqueRoundedLetterform = "Oblique/Rounded"
+    show ObliqueOffCenterLetterform = "Oblique/Off Center"
+    show ObliqueSquareLetterform = "Oblique/Square"
+
+instance Enum BLetterform
+  where
+    fromEnum AnyLetterform = 0
+    fromEnum NoFitLetterform = 1
+    fromEnum NormalContactLetterform = 2
+    fromEnum NormalWeightedLetterform = 3
+    fromEnum NormalBoxedLetterform = 4
+    fromEnum NormalFlattenedLetterform = 5
+    fromEnum NormalRoundedLetterform = 6
+    fromEnum NormalOffCenterLetterform = 7
+    fromEnum NormalSquareLetterform = 8
+    fromEnum ObliqueContactLetterform = 9
+    fromEnum ObliqueWeightedLetterform = 10
+    fromEnum ObliqueBoxedLetterform = 11
+    fromEnum ObliqueFlattenedLetterform = 12
+    fromEnum ObliqueRoundedLetterform = 13
+    fromEnum ObliqueOffCenterLetterform = 14
+    fromEnum ObliqueSquareLetterform = 15
+    toEnum 0 = AnyLetterform
+    toEnum 1 = NoFitLetterform
+    toEnum 2 = NormalContactLetterform
+    toEnum 3 = NormalWeightedLetterform
+    toEnum 4 = NormalBoxedLetterform
+    toEnum 5 = NormalFlattenedLetterform
+    toEnum 6 = NormalRoundedLetterform
+    toEnum 7 = NormalOffCenterLetterform
+    toEnum 8 = NormalSquareLetterform
+    toEnum 9 = ObliqueContactLetterform
+    toEnum 10 = ObliqueWeightedLetterform
+    toEnum 11 = ObliqueBoxedLetterform
+    toEnum 12 = ObliqueFlattenedLetterform
+    toEnum 13 = ObliqueRoundedLetterform
+    toEnum 14 = ObliqueOffCenterLetterform
+    toEnum 15 = ObliqueSquareLetterform
+    toEnum _ = error "Unknown letterform"
+
+data BMidline
+    = AnyMidline
+    | NoFitMidline
+    | StandardTrimmedMidline
+    | StandardPointedMidline
+    | StandardSerifedMidline
+    | HighTrimmedMidline
+    | HighPointedMidline
+    | HighSerifedMidline
+    | ConstantTrimmedMidline
+    | ConstantPointedMidline
+    | ConstantSerifedMidline
+    | LowTrimmedMidline
+    | LowPointedMidline
+    | LowSerifedMidline
+    deriving Eq
+
+instance Show BMidline
+  where
+    show AnyMidline = "Any"
+    show NoFitMidline = "No Fit"
+    show StandardTrimmedMidline = "Standard/Trimmed"
+    show StandardPointedMidline = "Standard/Pointed"
+    show StandardSerifedMidline = "Standard/Serifed"
+    show HighTrimmedMidline = "High/Trimmed"
+    show HighPointedMidline = "High/Pointed"
+    show HighSerifedMidline = "High/Serifed"
+    show ConstantTrimmedMidline = "Constant/Trimmed"
+    show ConstantPointedMidline = "Constant/Pointed"
+    show ConstantSerifedMidline = "Constant/Serifed"
+    show LowTrimmedMidline = "Low/Trimmed"
+    show LowPointedMidline = "Low/Pointed"
+    show LowSerifedMidline = "Low/Serifed"
+
+instance Enum BMidline
+  where
+    fromEnum AnyMidline = 0
+    fromEnum NoFitMidline = 1
+    fromEnum StandardTrimmedMidline = 2
+    fromEnum StandardPointedMidline = 3
+    fromEnum StandardSerifedMidline = 4
+    fromEnum HighTrimmedMidline = 5
+    fromEnum HighPointedMidline = 6
+    fromEnum HighSerifedMidline = 7
+    fromEnum ConstantTrimmedMidline = 8
+    fromEnum ConstantPointedMidline = 9
+    fromEnum ConstantSerifedMidline = 10
+    fromEnum LowTrimmedMidline = 11
+    fromEnum LowPointedMidline = 12
+    fromEnum LowSerifedMidline = 13
+    toEnum 0 = AnyMidline
+    toEnum 1 = NoFitMidline
+    toEnum 2 = StandardTrimmedMidline
+    toEnum 3 = StandardPointedMidline
+    toEnum 4 = StandardSerifedMidline
+    toEnum 5 = HighTrimmedMidline
+    toEnum 6 = HighPointedMidline
+    toEnum 7 = HighSerifedMidline
+    toEnum 8 = ConstantTrimmedMidline
+    toEnum 9 = ConstantPointedMidline
+    toEnum 10 = ConstantSerifedMidline
+    toEnum 11 = LowTrimmedMidline
+    toEnum 12 = LowPointedMidline
+    toEnum 13 = LowSerifedMidline
+    toEnum _ = error "Unknown midline"
+
+data BXHeight
+    = AnyXHeight
+    | NoFitXHeight
+    | ConstantSmallXHeight
+    | ConstantStandardXHeight
+    | ConstantLargeXHeight
+    | DuckingSmallXHeight
+    | DuckingStandardXHeight
+    | DuckingLargeXHeight
+    deriving Eq
+
+instance Show BXHeight
+  where
+    show AnyXHeight = "Any"
+    show NoFitXHeight = "No Fit"
+    show ConstantSmallXHeight = "Constant/Small"
+    show ConstantStandardXHeight = "Constant/Standard"
+    show ConstantLargeXHeight = "Constant/Large"
+    show DuckingSmallXHeight = "Ducking/Small"
+    show DuckingStandardXHeight = "Ducking/Standard"
+    show DuckingLargeXHeight = "Ducking/Large"
+
+instance Enum BXHeight
+  where
+    fromEnum AnyXHeight = 0
+    fromEnum NoFitXHeight = 1
+    fromEnum ConstantSmallXHeight = 2
+    fromEnum ConstantStandardXHeight = 3
+    fromEnum ConstantLargeXHeight = 4
+    fromEnum DuckingSmallXHeight = 5
+    fromEnum DuckingStandardXHeight = 6
+    fromEnum DuckingLargeXHeight = 7
+    toEnum 0 = AnyXHeight
+    toEnum 1 = NoFitXHeight
+    toEnum 2 = ConstantSmallXHeight
+    toEnum 3 = ConstantStandardXHeight
+    toEnum 4 = ConstantLargeXHeight
+    toEnum 5 = DuckingSmallXHeight
+    toEnum 6 = DuckingStandardXHeight
+    toEnum 7 = DuckingLargeXHeight
+    toEnum _ = error "Unknown X height"
+
+-- * Kern table
+
+newtype KernHeader = KernHeader
+    { version :: Fixed32 -- ^ The version number of the kerning table (0x00010000 for the current version).
+    } deriving (Eq, Show)
+
+data KernSubtableHeader = KernSubtableHeader
+    -- | The length of this subtable in bytes, including this header.
+    { length :: Word32
+    -- | Circumstances under which this table is used.
+    , coverage :: [Coverage]
+    -- | The tuple index (used for variations fonts). This value specifies which
+    -- tuple this subtable covers.
+    , tupleIndex :: Word16
+    } deriving (Eq, Show)
+
+data Coverage
+    = KernVertical -- ^ Set if table has vertical kerning values.
+    | KernCrossStream -- ^ Set if table has cross-stream kerning values.
+    | KernVariation -- ^ Set if table has variation kerning values.
+    | KernUnusedBits -- ^ Set to 0.
+    | KernFormatMask -- ^ Set the format of this subtable (0-3 currently defined).
+    deriving (Eq, Show)
+
+data KernFormat0Pair = KernFormat0Pair
+    { left :: Word16 -- ^ The glyph index for the lefthand glyph in the kerning pair.
+    , right :: Word16 -- ^ The glyph index for the righthand glyph in the kerning pair.
+    -- | The kerning value in FUnits for the left and right pair in FUnits.
+    -- If this value is greater than zero, the glyphs are moved apart.
+    -- If this value is less than zero, the glyphs are moved together.
+    , value :: Int16
+    } deriving (Eq, Show)
+
+data KernFormat0Table = KernFormat0Table
+    -- | The largest power of two less than or equal to the value of nPairs,
+    -- multiplied by the size in bytes of an entry in the subtable.
+    { searchRange :: Word16
+    -- | This is calculated as log2 of the largest power of two less than or
+    -- equal to the value of nPairs. This value indicates how many iterations of
+    -- the search loop have to be made. For example, in a list of eight items,
+    -- there would be three iterations of the loop.
+    , entrySelector :: Word16
+    -- | The value of nPairs minus the largest power of two less than or equal
+    -- to nPairs. This is multiplied by the size in bytes of an entry in the
+    -- table.
+    , rangeShift :: Word16
+    , pairs :: [KernFormat0Pair]
+    } deriving (Eq, Show)
+
+-- | Kern subtable format 1 header.
+data StateHeader = StateHeader
+    { stateSize :: Word16 -- ^ Number of classes defined for this table.
+    -- | Offset from the beginning of the state table to the beginning of the
+    -- class subtable.
+    , classTableOffset :: Word16
+    -- | Offset from the beginning of the state table to the beginning of the
+    -- state array.
+    , stateArrayOffset :: Word16
+    -- | Offset from the beginning of the state table to the beginning of the
+    -- entry subtable.
+    , entryTableOffset :: Word16
+    -- | Offset from the beginning of the state table to the beginning of the
+    -- state table values.
+    , valueOffset :: Word16
+    } deriving (Eq, Show)
+
+data StateEntry = StateEntry
+    { newState :: Word16
+    , flags :: Word16
+    } deriving (Eq, Show)
+
+data KernFormat1Table = KernFormat1Table
+    { stateHeader :: StateHeader
+    , firstGlyph :: Word16
+    , classArray :: ByteString
+    , stateArray :: ByteString
+    , entries :: [StateEntry]
+    } deriving (Eq, Show)
+
+data SimpleArrayHeader = SimpleArrayHeader
+    { rowWidth :: Word16 -- ^ The width, in bytes, of a row in the subtable.
+    -- | Offset from beginning of this subtable to the left-hand offset table.
+    , leftOffsetTable :: Word16
+    -- | Offset from beginning of this subtable to right-hand offset table.
+    , rightOffsetTable :: Word16
+    -- | Offset from beginning of this subtable to the start of the kerning
+    -- array.
+    , array :: Word16
+    } deriving (Eq, Show)
+
+data ClassTableHeader = ClassTableHeader
+    { firstGlyph -- ^ First glyph in class range.
+    -- | The offsets array for all of the glyphs in the range.
+    , offsets :: [Word16]
+    } deriving (Eq, Show)
+
+data KernFormat2Table = KernFormat2Table
+   { simpleArrayHeader :: SimpleArrayHeader
+   , classTableHeader :: ClassTableHeader
+   , values :: [Int16]
+   } deriving (Eq, Show)
+
+-- * 'gasp' table
+
+-- | Grid-fitting And Scan-conversion Procedure.
+data GASPTable = GASPTable
+    { version :: Word16 -- ^ Version number (set to 0).
+    , gaspRange :: [GASPRange] -- ^ Sorted by ppem.
+    } deriving (Eq, Show)
+
+data GASPRange = GASPRange
+    { rangeMaxPPEM :: Word16 -- ^ Upper limit of range, in PPEM.
+    , rangeGaspBehavior :: Word16 -- ^ Flags describing desired rasterizer behavior.
+    } deriving (Eq, Show)
+
+data RangeGaspBehavior
+    = KGASPGridFit -- ^ Use gridfitting.
+    | KGASPDoGray -- ^ Use grayscale rendering.
+    deriving (Eq, Show)
+
+instance Enum RangeGaspBehavior
+  where
+    toEnum 1 = KGASPGridFit
+    toEnum 2 = KGASPDoGray
+    toEnum _ = error "Unknown range GASP behavior"
+    fromEnum KGASPGridFit = 1
+    fromEnum KGASPDoGray = 2