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TABLE OF CONTENTS ttengine.library/background ttengine.library/font_database ttengine.library/TT_CloseFont ttengine.library/TT_DoneRastPort ttengine.library/TT_FreePixmap ttengine.library/TT_GetAttrsA ttengine.library/TT_GetPixmapA ttengine.library/TT_OpenFontA ttengine.library/TT_SetAttrsA ttengine.library/TT_SetFont ttengine.library/TT_Text ttengine.library/TT_TextExtent ttengine.library/TT_TextFit ttengine.library/TT_TextLength ttengine.library/background ttengine.library/background PURPOSE The library is fast, AmigaOS friendly TrueType render engine. It has nothing to do with Amiga outline font system. This system has a lot of limitations which make it useless for high speed and quality text output. If someone wants an integration of TrueType with AmigaOS bullet.library like outline font system, should consider using ttf.library. This library opens TrueType font by itself and renders high quality glyphs directly into any RastPort. FREETYPE2 BASED The render engine of the library is based on FreeType2 project (http://www.freetype.org). This version of ttengine.library uses 2.0.9 FreeType build. REQUIREMENTS - OS 3.0+. - 68020 or better processor. - for antialiased output graphics board with at least 15-bit screenmode and RTG system: CyberGraphX 3.x+ or Picasso96 2.x+. FEATURES The library expands FreeType functionality making usage of TrueType fonts easy and comfortable. Below you can find key features: - renders whole strings (not single glyphs) with kerning. - antialiasing to any (not neccesarily uniform color) background. - system compatible output to any (including planar) RastPort. - supports JAM1. JAM2, INVERSVID, COMPLEMENT RastPort modes. - supports 8-bit to Unicode mapping with "ENV:ttfcodepage" table compatible with ttf.library. - allows for direct 16-bit Unicode string rendering. - easy to use, taglist based API almost identical to graphics.library font API. - efficient system-wide glyph cache system. CACHE SYSTEM The library uses my own (not that experimental FreeType one) cache system speeding up strings rendering alot. The cache is system-wide, it means it is common to every application using ttengine.library. Only used glyphs of given font face are cached. If the library encounters cache miss, missing glyph is loaded and rasterized on the fly. Cache system is totally transparent to the library user, so there are no cache functions in the library API. Cache uses one single Exec memory pool avoiding memory fragmentation. ttengine.library/font_database ttengine.library/font_database GENERAL INFORMATION 'ttengine.database' is a plain text file (placed in 'ENV:' directory) containing informations about TrueType fonts available in the system. There is no tool (yet) to automatically generate it, the database have to be written by hand. Every line contains one keyword followed by parameter value. Name and value can be separated by space(s) or equality sign, exactly the same as shell command parameters (to say more - database is parsed by the same ReadArgs() system call as shell command parameters are). Parameter values containing spaces should be quoted. Here are some examples: FAMILY Tahoma FAMILY=Times FAMILY = "Times New Roman" FAMILY "Weird Font" KEYWORDS FAMILY - defines the name used for font opening. All variants of the font (italic, bold, black, heavy, light, demi etc.) will have the same family name. Family names (and aliases described below) are case insensitive. ALIAS - defines another name for the same family. It generally has three purposes: 1. Similar names for the same font, like "Times", "TimesNewRoman" and "Times New Roman". 2. One replacement font for some very similar ones, for example "Helvetica" and "Switzerland" can be aliased to "Arial". 3. Generic names like "default", "serif", "sans-serif", "monospaced". An application can request generic name without specific family name, or generic font can be used as a fallback if given name can't be found in the database. For example you can alias "monospaced" to "Courier", and an application (be it CSS compatible HTML viewer) can request 'LucidaConsole, monospaced'. If there is no LucidaConsole font in the system, Courier will be used. The same way you can alias any font to any other, for example Times to Arial, this makes not much sense however. 'default' font can be used as a last resort. FILE - defines single TrueType font file and its attributes, which are: FILE itself - defines a path to the font file. Font files can be placed anywhere in the filesystem(s). There is no default value for the attribute, it must be given explicitly. WEIGHT - defines font weight in Cascading Style Sheets manner, where 0 means the lightest and 999 means the heaviest weight. 400 is typical value for normal weight, 700 for bold. Default value is 400 (normal). STYLE - "regular" or "italic" for italic and oblique faces. Default value is "regular". SMOOTHSMALL - controls antialiasing of small sizes. Any sizes smaller or equal to SMOOTHSMALL will be antialiased. Note: can be overriden by application. Default value is 9. SMOOTHBIG - controls antialiasing of big sizes. Any sizes bigger or equal to SMOOTHBIG will be antialiased. Note: can be overriden by application. Default value is 18. Every FILE is automatically added to the nearest FAMILY defined above in the database file. Every ALIAS or FILE placed before the first FAMILY is rejected quietly. COMMENTS You can place any full-line comments in the file starting a line with hash or semicolon. End-line comments are not supported. ttengine.library/TT_CloseFont ttengine.library/TT_CloseFont NAME TT_CloseFont -- Closes TrueType font. (V4) SYNOPSIS TT_CloseFont (font) A0 VOID TT_CloseFont (APTR); FUNCTION Closes font opened by TT_OpenFontA() INPUTS font - the result of TT_OpenFontA(). Can be NULL, no action is taken in the case. RESULT none NOTES BUGS SEE ALSO TT_OpenFontA() ttengine.library/TT_DoneRastPort ttengine.library/TT_DoneRastPort NAME TT_DoneRastPort -- Releases TTEngine resources associated to a RastPort. (V5) SYNOPSIS TT_DoneRastPort (rastport) A1 VOID TT_DoneRastPort (struct RastPort*); FUNCTION Frees internal TTEngine resources associated with a RastPort. TTEngine creates rendering environment for every RastPort at first call of TT_SetFont() or TT_SetAttrs() for this RastPort. You should free this environment before disposing RastPort (typically before closing a window or screen). Leaving rendering environment not freed has two drawbacks. Firstly it causes memory leak, this memory is recovered however when ttengine.library is expunged. Secondly it is possible that a new RastPort will be created at the same address as disposed one. Then TTEngine will not create new rendering context but use old instead, which can lead to some unexpected behaviour. INPUTS rastport - pointer to RastPort. Rendering environment for this RastPort will be disposed. Can be NULL, in the case function does nothing. RESULT none EXAMPLE font = TT_OpenFont( /* tags */ ); window = OpenWindowTags(NULL, /* tags */); TT_SetFont(rport, font); /* environment is created here */ TT_SetAttrs(rport, TT_Window, window, /* ... */); /* you can call TT_SetAttrs() and TT_SetFont() as many times */ /* as you want */ TT_DoneRastPort(rport); /* environment is disposed */ CloseWindow(window); /* RastPort is disposed */ NOTES BUGS SEE ALSO TT_SetAttrsA(), TT_SetFont() ttengine.library/TT_FreePixmap ttengine.library/TT_FreePixmap NAME TT_FreePixmap -- Releases grayscale pixmap. (V5) SYNOPSIS TT_FreePixmap (pixmap) A0 VOID TT_FreePixmap (struct TT_Pixmap*); FUNCTION Frees pixmap data and structure allocated by TT_GetPixmap(). INPUTS pixmap - pointer to TT_Pixmap structure. May be NULL, function does nothing in the case. RESULT none NOTES BUGS SEE ALSO TT_GetPixmapA() ttengine.library/TT_GetAttrsA ttengine.library/TT_GetAttrsA NAME TT_GetAttrsA -- Gets current font and render engine attributes (V4). SYNOPSIS count = TT_GetAttrsA (rastport, taglist) A1 A0 ULONG TT_GetAttrsA (struct RastPort*, struct TagItem*); count = TT_GetAttrs (rastport, Tag1, ...) ULONG TT_GetAttrs (struct RastPort*, Tag, ...); FUNCTION Gets current font or render engine attributes for given RastPort. The value of every attribute is written to an ULONG pointed by ti_Data field of the TagItem. Here is a list of attributes: TT_Antialias - Current state of an antialias switch (on, off or auto). TT_FontAscender - This is a distance (in pixels) between the baseline and top elements of the font (typically these elements are accents of capital letters). NOTE: many shareware TT fonts have wrong ascen- der value. TT_FontDescender - This is a distance (in pixels) between the baseline and bottom elements of the font (typically in letters 'p', 'q', 'g' etc.). NOTE: many shareware TT fonts have wrong descender value. Descender value is typically negative (as bottom elements usually are placed below the baseline). TT_FontName - full font name as found in the font file. Pointer to a NULL-terminated string is written. This string is localized if the font file contains names in different languages. Language precedence is loaded from "Preferred languages" table of locale.library. TT_FamilyName - font family name as found in the font file. Pointer to a NULL-terminated string is written. This string is localized if the font file contains names in different languages. Language precedence is loaded from "Preferred languages" table of locale.library. TT_SubfamilyName - font subfamily name (typically describing font variant like "italic" or "bold") as found in the font file. Pointer to a NULL-terminated string is written. This string is localized if the font file contains names in different languages. Language precedence is loaded from "Preferred languages" table of locale.library. TT_Transparency - returns actual transparency setting. NOTE: TTFA_Ascender and TTFA_Descender are guarranted to fulfill following formula: ascender - descender = font height. INPUTS rastport - attributes associated with this RastPort will be returned. taglist - the list of attributes. RESULT counter - the count of recognized tags. NOTES Data returned are valid only until TT_CloseFont() call. BUGS SEE ALSO TT_OpenFontA(), TT_SetAttrsA() ttengine.library/TT_GetPixmapA ttengine.library/TT_GetPixmapA NAME TT_GetPixmapA -- Renders string to 8-bit grayscale pixel map. (V5) SYNOPSIS pixmap = TT_GetPixmapA (font, string, count, taglist) A1 A2 D0 A0 struct TT_Pixmap *TT_GetPixmapA (APTR, APTR, ULONG, struct TagItem*); pixmap = TT_GetPixmap (font, string, count, Tag1, ...) ULONG TT_GetPixmap (APTR, APTR, ULONG, Tag, ...); FUNCTION Renders a string to 8-bit grayscale pixel map. Function may be useful if the string image is additionally manipulated before rendering into RastPort (e.g. in image processing software). Pixel map is a continuous memory area where one byte represents one gray pixel (0 is black, 255 is white). The first byte is the upper left pixmap corner. Pixels are placed left-to-right in rows, rows are placed top-to-bottom. There is no row padding, it means pixmap modulo is always the same as pixmap width and pixmap data size is equal to width * height. The function accepts following tags: TT_Antialias - (BOOL) - controls antialiasing (on, off or automatic): TT_Antialias_Off - turns antialias off TT_Antialias_On - turns antialias on TT_Antialias_Auto (default) - antialias state depends on font size. Typically sizes of 9 or less pixels are antialiased, sizes from 10 to 19 pixels are not antialiased, sizes of 20 of more pixels are antialiased. These settings can be changed in the font database separately for every font face. TT_Encoding - selects font encoding table to be used: TT_Encoding_Default - loads encoding table from "ENV:ttfcodepage" file, compatible with ttf.library. If no such file is found, ISO-8859-1 encoding (Amiga default) is used. TT_Encoding_Unicode - strings are interpreted as tables of 16-bit Unicode characters. TT_Encoding_WideUnicode - strings are interpreted as tables of 32-bit Unicode characters. TT_Encoding_ISO8859_1 - ISO-8859-1 (Western Europe). TT_Encoding_ISO8859_2 - ISO-8859-2 (Eastern and Central Europe). TT_ScaleX - a floating point (IEEE single precision) horizontal scale factor. Its absolute value will be limited to <0.01, 100> range. It may be negative (it means horizontal mirror around starting pen position, string will be rendered to the left). TT_ScaleY - a floating point (IEEE single precision) vertical scale factor. Its absolute value will be limited to <0.01, 100> range. It may be negative (it means vertical mirror around the baseline, string will be rendered mostly under the baseline). INPUTS font - font pointer obtained with TT_OpenFont(). string - pointer to string to be rendered to a pixmap. count - length of the string in characters (only equal to bytes in pure 8-bit encodings). taglist - list of rendering attributes. RESULT pixmap - structure describing a pixmap defined as follows: struct TT_Pixmap { ULONG ttp_Size; ULONG ttp_Width; ULONG ttp_Height; UBYTE *ttp_Data; }; ttp_Size is the size of the structure (not the pixmap) containing useful informations including ttp_Size itself. For V5 pixmaps the size is 16 bytes. ttp_Width is pixmap width (and modulo) in bytes. ttp_Height is a number of pixmap rows. ttp_Data points to actual pixmap data. Function returns NULL if pixmap allocation fails. NOTES TT_Pixmap structure is READ ONLY. BUGS SEE ALSO TT_FreePixmap(), TT_OpenFontA(), TT_SetAtrrsA() ttengine.library/TT_OpenFontA ttengine.library/TT_OpenFontA NAME TT_OpenFontA -- Opens TrueType font. (V4) SYNOPSIS font = TT_OpenFontA (taglist) A0 APTR TT_OpenFontA (struct TagItem*); font = TT_OpenFont (Tag1, ...) APTR TT_OpenFont (Tag, ...); FUNCTION Opens a TrueType font preparing it to use with any RastPort. Font may be specified directly as a path to "*.ttf" file, or indirectly via set of attributes, database search will be performed for this set and best matching font will be opened. It is graphics.library OpenFont() counterpart but taglist is used instead TextAttr structure. INPUTS taglist - a list of tags containing requested font attributes. Following tags are recognized: TT_FontFile - this tag is a pointer to string containing a full path to TrueType font file to be opened. This tag allows for overriding database search and match. That means TT_FamilyTable, TT_FontStyle and TT_FontWeight are ignored if TT_FontFile is specified. Useful for opening application specific fonts, containing for example musical notes or some other kind of symbols. This tag has no default value. TT_FamilyTable - NULL-terminated table of pointers to font family names from the most desired to the last resort fallback. It is intended for easy implementing things like HTML 'FONT FACE' attribute. You can use real family names here, as well as generic names: 'serif', 'sans-serif', 'monospaced', 'cursive', 'fantasy', and 'default', especially useful as a fallbacks. Family names are case insensitive. The default value for the tag is {"default", NULL}; TT_FontSize - font size in pixels defined as the distance between baselines of two following text lines. The default value for this tag is 14 pixels. TT_FontStyle - there are three styles defined: TT_FontStyle_Regular (default), TT_FontStyle_Italic, TT_FontWeight - defined with Cascading Style Sheets manner as a number from 0 (the lightest face) to 999 (the heaviest face). You can use TT_FontWeight_Normal (equal to 400) and TT_FontWeight_Bold (equal to 700) shortcuts. TT_FontWeight_Normal is the default value. RESULT success - font pointer (for use with TT_SetFont() and TT_CloseFont()) if the font has been opened successfully, NULL otherwise. This function can fail for four reasons: 1. There is no matching face in the database (NOTE: even 'default' can fail if not defined in the database!) 2. File not found or malformed. 3. Zero font size. 4. No memory for requested (too big?) size. NOTES BUGS SEE ALSO TT_SetFont(), TT_CloseFont(), font_database ttengine.library/TT_SetAttrsA ttengine.library/TT_SetAttrsA NAME TT_SetAttrsA -- Sets rendering engine and font attributes. (V4) SYNOPSIS count = TT_SetAttrsA (rastport, taglist) A1 A0 ULONG TT_SetAttrsA (struct RastPort*, struct TagItem*); count = TT_SetAttrs (rastport, Tag1, ...) ULONG TT_SetAttrs (struct RastPort*, Tag, ...); FUNCTION Sets render engine settings for given RastPort. Every following TrutType render and metrics calls for this RastPort will use these settings. Here is a list of attributes: TT_ColorMap - (struct ColorMap*) - ColorMap used to convert pen number to RGB color value. TT_Screen - (struct Screen*) - useful shortcut for TT_ColorMap, automatically sets screen ColorMap. TT_Window - (struct Window*) - useful shortcut for TT_ColorMap, automatically sets window ColorMap. TT_Antialias - (BOOL) - controls antialiasing (on, off or automatic): TT_Antialias_Off - turns antialias off TT_Antialias_On - turns antialias on TT_Antialias_Auto (default) - antialias state depends on font size. Typically sizes of 9 or less pixels are antialiased, sizes from 10 to 19 pixels are not antialiased, sizes of 20 of more pixels are antialiased. These settings can be changed in the font database separately for every font face. TT_Encoding - selects font encoding table to be used: TT_Encoding_Default - loads encoding table from "ENV:ttfcodepage" file, compatible with ttf.library. If no such file is found, ISO-8859-1 encoding (Amiga default) is used. TT_Encoding_Unicode - strings are interpreted as tables of 16-bit Unicode characters. TT_Encoding_ISO8859_1 - ISO-8859-1 (Western Europe). TT_Encoding_ISO8859_2 - ISO-8859-2 (Eastern and Central Europe). TT_Transparency - Allows for rendering transparent text (the background shines through the text). 0 value means no transparency (this is the default), 255 is maximum transparency. TT_ScaleX - a floating point (IEEE single precision) horizontal scale factor. Its absolute value will be limited to <0.01, 100> range. It may be negative (it means horizontal mirror around starting pen position, string will be rendered to the left). TT_ScaleY - a floating point (IEEE single precision) vertical scale factor. Its absolute value will be limited to <0.01, 100> range. It may be negative (it means vertical mirror around the baseline, string will be rendered mostly under the baseline). TT_SoftStyle - controls software generated font modifications. Any of software styles can be combined (OR-ing the values). TT_SoftStyle_None - clears all software styles. TT_SoftStyle_Underlined - boolean tag controlling text underline. TT_SoftStyle_DblUnderlined - boolean tag controlling text double underline. Combining it with TT_Underlined gives one thick line. TT_SoftStyle_Overstriked - boolean tag controlling text overstriked line. TT_SoftStyle_DblOverstriked - boolean tag controlling text overstriked double line. Combining it with TT_Overstriked gives one thick line. TT_Foreground - allows for using direct RGB value of foreground color instead of RastPort 'A' pen. On LUT screens this tag will be ignored. Special value TT_Foreground_UseRastPort returns foreground color control back to the RastPort and its 'A' pen. TT_Background - allows for using direct RGB value of background color (used in JAM2 drawmode only) instead of RastPort 'B' pen. On LUT screens this tag will be ignored. Special value TT_Background_UseRastPort returns background color control back to the RastPort and its 'B' pen. INPUTS rastport - attributes will be set for this RastPort. taglist - the list of attributes. RESULT counter - the count of recognized tags. NOTES BUGS SEE ALSO TT_OpenFontA(), TT_Text(), TT_GetAttrs() ttengine.library/TT_SetFont ttengine.library/TT_SetFont NAME TT_SetFont -- Sets TrueType font for a RastPort. (V4) SYNOPSIS TT_SetFont (rastport, font) A1 A0 BOOL TT_SetFont (struct RastPort*, APTR); FUNCTION Sets a font previously opened with TT_OpenFontA() for use with given RastPort. All further calls of text rendering or metrics function for this RastPort will use font set. INPUTS rastport - The font will be set for this RastPort. font - Pointer returned by TT_OpenFontA(). May be NULL, function returns immediately in the case. RESULT TRUE if success, false otherwise. EXAMPLE /* use two fonts to render in one RastPort */ APTR times, arial; times = TT_OpenFont( TT_FamilyTable, (ULONG){"Times", "serif", "default", NULL}, TT_FontSize, 26, TAG_END); arial = TT_OpenFont( TT_FamilyTable, (ULONG){"Arial", "sans-serif", "default", NULL}, TT_FontSize, 22, TT_FontWeight, TT_FontWeight_Bold, TAG_END); if (times && arial) { SetAPen(win->RPort, 1); SetDrMd(win->RPort, JAM1); Move(win->RPort, 100, 100); TT_SetAttrs(win->RPort, TT_Window, win, TAG_END); if (TT_SetFont(win->RPort, times)) TT_Text(win->RPort, "Times 26 points", 15); if (TT_SetFont(win->RPort, arial)) TT_Text(win->RPort, "Arial 22 points", 15); } if (arial) TT_CloseFont(arial); if (times) TT_CloseFont(times); NOTES Function can fail returning FALSE if: 1. RastPort pointer is NULL. 2. Font pointer is NULL. 3. Font pointer is not found on opened fonts list (it means the pointer was not obtained as a result of TT_OpenFontA() call). 4. Memory allocation during environment creation fails. BUGS SEE ALSO TT_OpenFontA(), TT_SetAttrsA(), TT_CloseFont() ttengine.library/TT_Text ttengine.library/TT_Text NAME TT_Text -- Renders string into RastPort. (V4) SYNOPSIS TT_Text (rastport, string, count) A1 A0 D0 VOID TT_Text (struct RastPort*, APTR, ULONG); FUNCTION Renders the string using current ttengine.library settings, and current RastPort settings (pen, drawmode). String is rendered at current RastPort (x, y) position, where 'y' means position of font baseline. String is converted to Unicode according to current (set by TT_SetAttrs()) encoding table. INPUTS rastport - Target RastPort for rendering. string - String to render to (need not to be NULL terminated). count - How many characters to render (note that NULL code will be rendered as well). RESULT none EXAMPLE /* write a text with pen 1 and transp. background at (100, 100) */ /* rendering is done to a system window */ SetAPen(win->RPort, 1); SetDrMd(win->RPort, JAM1); Move(win->RPort, 100, 100); TT_SetAttrs(win->RPort, TT_Window, win, TAG_END); TT_Text(win->RPort, "some text", 9); NOTES BUGS SEE ALSO TT_OpenFontA(), TT_SetAttrsA() ttengine.library/TT_TextExtent ttengine.library/TT_TextExtent NAME TT_TextExtent -- Determine raster extent of text data. (V4) SYNOPSIS TT_TextExtent (rastport, text, count, extent) A1 A0 D0:16 A2 VOID TT_TextExtent (struct RastPort*, APTR, WORD, struct TextExtent*); FUNCTION Computes dimensions and coordinates of smallest rectangle containing on the whole given text rendered with current settings. TextExtent structure fields have following meaning: te_Width - Horizontal advance of RastPort pen position. The same as TT_TextLength() call result. te_Height - Just current font height. te_Extent.MinX - The horizontal distance from text start point to the leftmost pixel rendered. May be negative, it means that some pixels will be plotted before the start point. te_Extent.MaxX - The horizontal distance from text start point to the rightmost pixel rendered. te_Extent.MinY - The vertical distance from text start point to the topmost pixel rendered. Always negative, do not neccesarily equal to -TTFA_Ascender. te_Extent.MaxY - The vertical distance from text start point to the lowermost pixel rendered. Typically positive if anything is to be drawn below the baseline. INPUTS rastport - this rastport settings (font, size, style etc.) will be used for calculations. text - a string (not neccesarily NULL-terminated) to compute the rectangle for. count - length of the string in characters. extent - pointer to TextExtent structure - it will be filled with data. RESULT No retrurn value. TextExtent structure is filled with data. NOTES This function is almost identical to graphics.library/TextExtent(). It even receives parameters in the same registers. Do not assume neither horizontal extents sum up to te_Width, nor vertical ones sum up to font height. BUGS SEE ALSO TT_OpenFontA(), graphics.library/TextExtent() ttengine.library/TT_TextFit ttengine.library/TT_TextFit NAME TT_TextFit -- Count characters that will fit in a given extent. (V4) SYNOPSIS characters = TT_TextFit (rastport, string, count, extent, A1 A0 D0:16 A2 constr_extent, direction, width, height) A3 D1 D2 D3 ULONG TT_TextFit (struct RastPort*, APTR, UWORD, struct TextExtent*, struct TextExtent*, WORD, UWORD, UWORD); FUNCTION Computes how many characters of given NULL-terminated string rendered with current settings will fit into given extent. Also calculates an extent for this fitting part of the string. Function can fit from the beginning of the string to the right, or from the end of the string to the left. If 'constr_extent' is non NULL, string is fitted only against it, constraining 'width' and 'height' are ignored. INPUTS rastport - calculations will be performed using this rastport settings (font, size, styles etc.). string - A string (not neccesarily NULL-terminated) to fit. count - string lenght in characters. extent - Pointer to TextExtent structure - it will be filled with dimensions of fitted part of the string. May be filled with all zeros if no fit is possible at all (e.g. height is to small). constr_extent - Pointer to already filled TextExtent structure. Part of the string will fit into this extent. It is not modified by function. May be NULL, 'width' and 'height' will be used as constraints. direction - When equal to 1 string will be fitted starting from it's beginning to the rigth. When equal to -1, string will be fitted starting from it's end to the left. width - If 'constr_extent' is NULL, the string width will be compared with this parameter. Ignored otherwise. height - If 'constr_extent' is NULL, the string height will be compared with this parameter. Ignored otherwise. RESULT characters - the length of fitting string part. May be zero if no fit found. NOTES This function is almost identical to graphics.library/TextFit(). It even receives parameters in the same registers. Do not assume neither horizontal extents sum up to te_Width, nor vertical ones sum up to font height (in returned extent). BUGS SEE ALSO TT_OpenFontA(), graphics.library/TextFit() ttengine.library/TT_TextLength ttengine.library/TT_TextLength NAME TT_TextLength -- Gets string length in pixels (V4). SYNOPSIS length = TT_TextLength(rastport, string, count) A1 A0 D0 ULONG TT_TextLength (struct RastPort*, APTR, ULONG); FUNCTION Calculates the pixel width of given string written with current font. Takes kerning into account. String will be mapped to Unicode using current encoding. INPUTS rastport - render engine and font settings for this RastPort will be used for calculations. string - the length of this string will be calculated. count - the string lenght in characters. RESULT length - the length of the string in pixels. NOTES BUGS SEE ALSO TT_Text(), TT_OpenFontA()