| /***************************************************************************/ |
| /* */ |
| /* ftoutln.h */ |
| /* */ |
| /* Support for the FT_Outline type used to store glyph shapes of */ |
| /* most scalable font formats (specification). */ |
| /* */ |
| /* Copyright 1996-2003, 2005-2014 by */ |
| /* David Turner, Robert Wilhelm, and Werner Lemberg. */ |
| /* */ |
| /* This file is part of the FreeType project, and may only be used, */ |
| /* modified, and distributed under the terms of the FreeType project */ |
| /* license, LICENSE.TXT. By continuing to use, modify, or distribute */ |
| /* this file you indicate that you have read the license and */ |
| /* understand and accept it fully. */ |
| /* */ |
| /***************************************************************************/ |
| |
| |
| #ifndef __FTOUTLN_H__ |
| #define __FTOUTLN_H__ |
| |
| |
| #include <ft2build.h> |
| #include FT_FREETYPE_H |
| |
| #ifdef FREETYPE_H |
| #error "freetype.h of FreeType 1 has been loaded!" |
| #error "Please fix the directory search order for header files" |
| #error "so that freetype.h of FreeType 2 is found first." |
| #endif |
| |
| |
| FT_BEGIN_HEADER |
| |
| |
| /*************************************************************************/ |
| /* */ |
| /* <Section> */ |
| /* outline_processing */ |
| /* */ |
| /* <Title> */ |
| /* Outline Processing */ |
| /* */ |
| /* <Abstract> */ |
| /* Functions to create, transform, and render vectorial glyph images. */ |
| /* */ |
| /* <Description> */ |
| /* This section contains routines used to create and destroy scalable */ |
| /* glyph images known as `outlines'. These can also be measured, */ |
| /* transformed, and converted into bitmaps and pixmaps. */ |
| /* */ |
| /* <Order> */ |
| /* FT_Outline */ |
| /* FT_Outline_New */ |
| /* FT_Outline_Done */ |
| /* FT_Outline_Copy */ |
| /* FT_Outline_Translate */ |
| /* FT_Outline_Transform */ |
| /* FT_Outline_Embolden */ |
| /* FT_Outline_EmboldenXY */ |
| /* FT_Outline_Reverse */ |
| /* FT_Outline_Check */ |
| /* */ |
| /* FT_Outline_Get_CBox */ |
| /* FT_Outline_Get_BBox */ |
| /* */ |
| /* FT_Outline_Get_Bitmap */ |
| /* FT_Outline_Render */ |
| /* FT_Outline_Decompose */ |
| /* FT_Outline_Funcs */ |
| /* FT_Outline_MoveToFunc */ |
| /* FT_Outline_LineToFunc */ |
| /* FT_Outline_ConicToFunc */ |
| /* FT_Outline_CubicToFunc */ |
| /* */ |
| /* FT_Orientation */ |
| /* FT_Outline_Get_Orientation */ |
| /* */ |
| /* FT_OUTLINE_XXX */ |
| /* */ |
| /*************************************************************************/ |
| |
| |
| /*************************************************************************/ |
| /* */ |
| /* <Function> */ |
| /* FT_Outline_Decompose */ |
| /* */ |
| /* <Description> */ |
| /* Walk over an outline's structure to decompose it into individual */ |
| /* segments and Bézier arcs. This function also emits `move to' */ |
| /* operations to indicate the start of new contours in the outline. */ |
| /* */ |
| /* <Input> */ |
| /* outline :: A pointer to the source target. */ |
| /* */ |
| /* func_interface :: A table of `emitters', i.e., function pointers */ |
| /* called during decomposition to indicate path */ |
| /* operations. */ |
| /* */ |
| /* <InOut> */ |
| /* user :: A typeless pointer that is passed to each */ |
| /* emitter during the decomposition. It can be */ |
| /* used to store the state during the */ |
| /* decomposition. */ |
| /* */ |
| /* <Return> */ |
| /* FreeType error code. 0~means success. */ |
| /* */ |
| /* <Note> */ |
| /* A contour that contains a single point only is represented by a */ |
| /* `move to' operation followed by `line to' to the same point. In */ |
| /* most cases, it is best to filter this out before using the */ |
| /* outline for stroking purposes (otherwise it would result in a */ |
| /* visible dot when round caps are used). */ |
| /* */ |
| FT_EXPORT( FT_Error ) |
| FT_Outline_Decompose( FT_Outline* outline, |
| const FT_Outline_Funcs* func_interface, |
| void* user ); |
| |
| |
| /*************************************************************************/ |
| /* */ |
| /* <Function> */ |
| /* FT_Outline_New */ |
| /* */ |
| /* <Description> */ |
| /* Create a new outline of a given size. */ |
| /* */ |
| /* <Input> */ |
| /* library :: A handle to the library object from where the */ |
| /* outline is allocated. Note however that the new */ |
| /* outline will *not* necessarily be *freed*, when */ |
| /* destroying the library, by @FT_Done_FreeType. */ |
| /* */ |
| /* numPoints :: The maximum number of points within the outline. */ |
| /* Must be smaller than or equal to 0xFFFF (65535). */ |
| /* */ |
| /* numContours :: The maximum number of contours within the outline. */ |
| /* This value must be in the range 0 to `numPoints'. */ |
| /* */ |
| /* <Output> */ |
| /* anoutline :: A handle to the new outline. */ |
| /* */ |
| /* <Return> */ |
| /* FreeType error code. 0~means success. */ |
| /* */ |
| /* <Note> */ |
| /* The reason why this function takes a `library' parameter is simply */ |
| /* to use the library's memory allocator. */ |
| /* */ |
| FT_EXPORT( FT_Error ) |
| FT_Outline_New( FT_Library library, |
| FT_UInt numPoints, |
| FT_Int numContours, |
| FT_Outline *anoutline ); |
| |
| |
| FT_EXPORT( FT_Error ) |
| FT_Outline_New_Internal( FT_Memory memory, |
| FT_UInt numPoints, |
| FT_Int numContours, |
| FT_Outline *anoutline ); |
| |
| |
| /*************************************************************************/ |
| /* */ |
| /* <Function> */ |
| /* FT_Outline_Done */ |
| /* */ |
| /* <Description> */ |
| /* Destroy an outline created with @FT_Outline_New. */ |
| /* */ |
| /* <Input> */ |
| /* library :: A handle of the library object used to allocate the */ |
| /* outline. */ |
| /* */ |
| /* outline :: A pointer to the outline object to be discarded. */ |
| /* */ |
| /* <Return> */ |
| /* FreeType error code. 0~means success. */ |
| /* */ |
| /* <Note> */ |
| /* If the outline's `owner' field is not set, only the outline */ |
| /* descriptor will be released. */ |
| /* */ |
| /* The reason why this function takes an `library' parameter is */ |
| /* simply to use ft_mem_free(). */ |
| /* */ |
| FT_EXPORT( FT_Error ) |
| FT_Outline_Done( FT_Library library, |
| FT_Outline* outline ); |
| |
| |
| FT_EXPORT( FT_Error ) |
| FT_Outline_Done_Internal( FT_Memory memory, |
| FT_Outline* outline ); |
| |
| |
| /*************************************************************************/ |
| /* */ |
| /* <Function> */ |
| /* FT_Outline_Check */ |
| /* */ |
| /* <Description> */ |
| /* Check the contents of an outline descriptor. */ |
| /* */ |
| /* <Input> */ |
| /* outline :: A handle to a source outline. */ |
| /* */ |
| /* <Return> */ |
| /* FreeType error code. 0~means success. */ |
| /* */ |
| FT_EXPORT( FT_Error ) |
| FT_Outline_Check( FT_Outline* outline ); |
| |
| |
| /*************************************************************************/ |
| /* */ |
| /* <Function> */ |
| /* FT_Outline_Get_CBox */ |
| /* */ |
| /* <Description> */ |
| /* Return an outline's `control box'. The control box encloses all */ |
| /* the outline's points, including Bézier control points. Though it */ |
| /* coincides with the exact bounding box for most glyphs, it can be */ |
| /* slightly larger in some situations (like when rotating an outline */ |
| /* that contains Bézier outside arcs). */ |
| /* */ |
| /* Computing the control box is very fast, while getting the bounding */ |
| /* box can take much more time as it needs to walk over all segments */ |
| /* and arcs in the outline. To get the latter, you can use the */ |
| /* `ftbbox' component, which is dedicated to this single task. */ |
| /* */ |
| /* <Input> */ |
| /* outline :: A pointer to the source outline descriptor. */ |
| /* */ |
| /* <Output> */ |
| /* acbox :: The outline's control box. */ |
| /* */ |
| /* <Note> */ |
| /* See @FT_Glyph_Get_CBox for a discussion of tricky fonts. */ |
| /* */ |
| FT_EXPORT( void ) |
| FT_Outline_Get_CBox( const FT_Outline* outline, |
| FT_BBox *acbox ); |
| |
| |
| /*************************************************************************/ |
| /* */ |
| /* <Function> */ |
| /* FT_Outline_Translate */ |
| /* */ |
| /* <Description> */ |
| /* Apply a simple translation to the points of an outline. */ |
| /* */ |
| /* <InOut> */ |
| /* outline :: A pointer to the target outline descriptor. */ |
| /* */ |
| /* <Input> */ |
| /* xOffset :: The horizontal offset. */ |
| /* */ |
| /* yOffset :: The vertical offset. */ |
| /* */ |
| FT_EXPORT( void ) |
| FT_Outline_Translate( const FT_Outline* outline, |
| FT_Pos xOffset, |
| FT_Pos yOffset ); |
| |
| |
| /*************************************************************************/ |
| /* */ |
| /* <Function> */ |
| /* FT_Outline_Copy */ |
| /* */ |
| /* <Description> */ |
| /* Copy an outline into another one. Both objects must have the */ |
| /* same sizes (number of points & number of contours) when this */ |
| /* function is called. */ |
| /* */ |
| /* <Input> */ |
| /* source :: A handle to the source outline. */ |
| /* */ |
| /* <Output> */ |
| /* target :: A handle to the target outline. */ |
| /* */ |
| /* <Return> */ |
| /* FreeType error code. 0~means success. */ |
| /* */ |
| FT_EXPORT( FT_Error ) |
| FT_Outline_Copy( const FT_Outline* source, |
| FT_Outline *target ); |
| |
| |
| /*************************************************************************/ |
| /* */ |
| /* <Function> */ |
| /* FT_Outline_Transform */ |
| /* */ |
| /* <Description> */ |
| /* Apply a simple 2x2 matrix to all of an outline's points. Useful */ |
| /* for applying rotations, slanting, flipping, etc. */ |
| /* */ |
| /* <InOut> */ |
| /* outline :: A pointer to the target outline descriptor. */ |
| /* */ |
| /* <Input> */ |
| /* matrix :: A pointer to the transformation matrix. */ |
| /* */ |
| /* <Note> */ |
| /* You can use @FT_Outline_Translate if you need to translate the */ |
| /* outline's points. */ |
| /* */ |
| FT_EXPORT( void ) |
| FT_Outline_Transform( const FT_Outline* outline, |
| const FT_Matrix* matrix ); |
| |
| |
| /*************************************************************************/ |
| /* */ |
| /* <Function> */ |
| /* FT_Outline_Embolden */ |
| /* */ |
| /* <Description> */ |
| /* Embolden an outline. The new outline will be at most 4~times */ |
| /* `strength' pixels wider and higher. You may think of the left and */ |
| /* bottom borders as unchanged. */ |
| /* */ |
| /* Negative `strength' values to reduce the outline thickness are */ |
| /* possible also. */ |
| /* */ |
| /* <InOut> */ |
| /* outline :: A handle to the target outline. */ |
| /* */ |
| /* <Input> */ |
| /* strength :: How strong the glyph is emboldened. Expressed in */ |
| /* 26.6 pixel format. */ |
| /* */ |
| /* <Return> */ |
| /* FreeType error code. 0~means success. */ |
| /* */ |
| /* <Note> */ |
| /* The used algorithm to increase or decrease the thickness of the */ |
| /* glyph doesn't change the number of points; this means that certain */ |
| /* situations like acute angles or intersections are sometimes */ |
| /* handled incorrectly. */ |
| /* */ |
| /* If you need `better' metrics values you should call */ |
| /* @FT_Outline_Get_CBox or @FT_Outline_Get_BBox. */ |
| /* */ |
| /* Example call: */ |
| /* */ |
| /* { */ |
| /* FT_Load_Glyph( face, index, FT_LOAD_DEFAULT ); */ |
| /* if ( face->slot->format == FT_GLYPH_FORMAT_OUTLINE ) */ |
| /* FT_Outline_Embolden( &face->slot->outline, strength ); */ |
| /* } */ |
| /* */ |
| /* To get meaningful results, font scaling values must be set with */ |
| /* functions like @FT_Set_Char_Size before calling FT_Render_Glyph. */ |
| /* */ |
| FT_EXPORT( FT_Error ) |
| FT_Outline_Embolden( FT_Outline* outline, |
| FT_Pos strength ); |
| |
| |
| /*************************************************************************/ |
| /* */ |
| /* <Function> */ |
| /* FT_Outline_EmboldenXY */ |
| /* */ |
| /* <Description> */ |
| /* Embolden an outline. The new outline will be `xstrength' pixels */ |
| /* wider and `ystrength' pixels higher. Otherwise, it is similar to */ |
| /* @FT_Outline_Embolden, which uses the same strength in both */ |
| /* directions. */ |
| /* */ |
| FT_EXPORT( FT_Error ) |
| FT_Outline_EmboldenXY( FT_Outline* outline, |
| FT_Pos xstrength, |
| FT_Pos ystrength ); |
| |
| |
| /*************************************************************************/ |
| /* */ |
| /* <Function> */ |
| /* FT_Outline_Reverse */ |
| /* */ |
| /* <Description> */ |
| /* Reverse the drawing direction of an outline. This is used to */ |
| /* ensure consistent fill conventions for mirrored glyphs. */ |
| /* */ |
| /* <InOut> */ |
| /* outline :: A pointer to the target outline descriptor. */ |
| /* */ |
| /* <Note> */ |
| /* This function toggles the bit flag @FT_OUTLINE_REVERSE_FILL in */ |
| /* the outline's `flags' field. */ |
| /* */ |
| /* It shouldn't be used by a normal client application, unless it */ |
| /* knows what it is doing. */ |
| /* */ |
| FT_EXPORT( void ) |
| FT_Outline_Reverse( FT_Outline* outline ); |
| |
| |
| /*************************************************************************/ |
| /* */ |
| /* <Function> */ |
| /* FT_Outline_Get_Bitmap */ |
| /* */ |
| /* <Description> */ |
| /* Render an outline within a bitmap. The outline's image is simply */ |
| /* OR-ed to the target bitmap. */ |
| /* */ |
| /* <Input> */ |
| /* library :: A handle to a FreeType library object. */ |
| /* */ |
| /* outline :: A pointer to the source outline descriptor. */ |
| /* */ |
| /* <InOut> */ |
| /* abitmap :: A pointer to the target bitmap descriptor. */ |
| /* */ |
| /* <Return> */ |
| /* FreeType error code. 0~means success. */ |
| /* */ |
| /* <Note> */ |
| /* This function does NOT CREATE the bitmap, it only renders an */ |
| /* outline image within the one you pass to it! Consequently, the */ |
| /* various fields in `abitmap' should be set accordingly. */ |
| /* */ |
| /* It will use the raster corresponding to the default glyph format. */ |
| /* */ |
| /* The value of the `num_grays' field in `abitmap' is ignored. If */ |
| /* you select the gray-level rasterizer, and you want less than 256 */ |
| /* gray levels, you have to use @FT_Outline_Render directly. */ |
| /* */ |
| FT_EXPORT( FT_Error ) |
| FT_Outline_Get_Bitmap( FT_Library library, |
| FT_Outline* outline, |
| const FT_Bitmap *abitmap ); |
| |
| |
| /*************************************************************************/ |
| /* */ |
| /* <Function> */ |
| /* FT_Outline_Render */ |
| /* */ |
| /* <Description> */ |
| /* Render an outline within a bitmap using the current scan-convert. */ |
| /* This function uses an @FT_Raster_Params structure as an argument, */ |
| /* allowing advanced features like direct composition, translucency, */ |
| /* etc. */ |
| /* */ |
| /* <Input> */ |
| /* library :: A handle to a FreeType library object. */ |
| /* */ |
| /* outline :: A pointer to the source outline descriptor. */ |
| /* */ |
| /* <InOut> */ |
| /* params :: A pointer to an @FT_Raster_Params structure used to */ |
| /* describe the rendering operation. */ |
| /* */ |
| /* <Return> */ |
| /* FreeType error code. 0~means success. */ |
| /* */ |
| /* <Note> */ |
| /* You should know what you are doing and how @FT_Raster_Params works */ |
| /* to use this function. */ |
| /* */ |
| /* The field `params.source' will be set to `outline' before the scan */ |
| /* converter is called, which means that the value you give to it is */ |
| /* actually ignored. */ |
| /* */ |
| /* The gray-level rasterizer always uses 256 gray levels. If you */ |
| /* want less gray levels, you have to provide your own span callback. */ |
| /* See the @FT_RASTER_FLAG_DIRECT value of the `flags' field in the */ |
| /* @FT_Raster_Params structure for more details. */ |
| /* */ |
| FT_EXPORT( FT_Error ) |
| FT_Outline_Render( FT_Library library, |
| FT_Outline* outline, |
| FT_Raster_Params* params ); |
| |
| |
| /************************************************************************** |
| * |
| * @enum: |
| * FT_Orientation |
| * |
| * @description: |
| * A list of values used to describe an outline's contour orientation. |
| * |
| * The TrueType and PostScript specifications use different conventions |
| * to determine whether outline contours should be filled or unfilled. |
| * |
| * @values: |
| * FT_ORIENTATION_TRUETYPE :: |
| * According to the TrueType specification, clockwise contours must |
| * be filled, and counter-clockwise ones must be unfilled. |
| * |
| * FT_ORIENTATION_POSTSCRIPT :: |
| * According to the PostScript specification, counter-clockwise contours |
| * must be filled, and clockwise ones must be unfilled. |
| * |
| * FT_ORIENTATION_FILL_RIGHT :: |
| * This is identical to @FT_ORIENTATION_TRUETYPE, but is used to |
| * remember that in TrueType, everything that is to the right of |
| * the drawing direction of a contour must be filled. |
| * |
| * FT_ORIENTATION_FILL_LEFT :: |
| * This is identical to @FT_ORIENTATION_POSTSCRIPT, but is used to |
| * remember that in PostScript, everything that is to the left of |
| * the drawing direction of a contour must be filled. |
| * |
| * FT_ORIENTATION_NONE :: |
| * The orientation cannot be determined. That is, different parts of |
| * the glyph have different orientation. |
| * |
| */ |
| typedef enum FT_Orientation_ |
| { |
| FT_ORIENTATION_TRUETYPE = 0, |
| FT_ORIENTATION_POSTSCRIPT = 1, |
| FT_ORIENTATION_FILL_RIGHT = FT_ORIENTATION_TRUETYPE, |
| FT_ORIENTATION_FILL_LEFT = FT_ORIENTATION_POSTSCRIPT, |
| FT_ORIENTATION_NONE |
| |
| } FT_Orientation; |
| |
| |
| /************************************************************************** |
| * |
| * @function: |
| * FT_Outline_Get_Orientation |
| * |
| * @description: |
| * This function analyzes a glyph outline and tries to compute its |
| * fill orientation (see @FT_Orientation). This is done by integrating |
| * the total area covered by the outline. The positive integral |
| * corresponds to the clockwise orientation and @FT_ORIENTATION_POSTSCRIPT |
| * is returned. The negative integral corresponds to the counter-clockwise |
| * orientation and @FT_ORIENTATION_TRUETYPE is returned. |
| * |
| * Note that this will return @FT_ORIENTATION_TRUETYPE for empty |
| * outlines. |
| * |
| * @input: |
| * outline :: |
| * A handle to the source outline. |
| * |
| * @return: |
| * The orientation. |
| * |
| */ |
| FT_EXPORT( FT_Orientation ) |
| FT_Outline_Get_Orientation( FT_Outline* outline ); |
| |
| /* */ |
| |
| |
| FT_END_HEADER |
| |
| #endif /* __FTOUTLN_H__ */ |
| |
| |
| /* END */ |
| |
| |
| /* Local Variables: */ |
| /* coding: utf-8 */ |
| /* End: */ |
