[SOLVED] CS algorithm /***************************************************************************/

/***************************************************************************/
/* */
/*ftoutln.h*/
/* */
/*Support for the FT_Outline type used to store glyph shapes of*/
/*most scalable font formats (specification).*/
/* */
/*Copyright 1996-2015 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
#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

/*************************************************************************/
/* */
/*

/*************************************************************************/
/* */
/* */
/*FT_Outline_Decompose */
/* */
/* */
/*Walk over an outlines structure to decompose it into individual */
/*segments and Bzier arcs.This function also emits `move to*/
/*operations to indicate the start of new contours in the outline. */
/* */
/**/
/*outline:: A pointer to the source target.*/
/* */
/*func_interface :: A table of `emitters, i.e., function pointers */
/*called during decomposition to indicate path */
/*operations.*/
/* */
/* */
/*user :: A typeless pointer that is passed to each*/
/*emitter during the decomposition.It can be */
/*used to store the state during the */
/*decomposition. */
/* */
/* */
/*FreeType error code.0~means success. */
/* */
/* */
/*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 );

/*************************************************************************/
/* */
/* */
/*FT_Outline_New */
/* */
/* */
/*Create a new outline of a given size.*/
/* */
/**/
/*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. */
/* */
/*

*/
/*anoutline :: A handle to the new outline.*/
/* */
/* */
/*FreeType error code.0~means success. */
/* */
/* */
/*The reason why this function takes a `library parameter is simply */
/*to use the librarys memory allocator. */
/* */
FT_EXPORT( FT_Error )
FT_Outline_New( FT_Library library,
FT_UIntnumPoints,
FT_Int numContours,
FT_Outline*anoutline );

FT_EXPORT( FT_Error )
FT_Outline_New_Internal( FT_Memorymemory,
FT_UIntnumPoints,
FT_Int numContours,
FT_Outline*anoutline );

/*************************************************************************/
/* */
/* */
/*FT_Outline_Done*/
/* */
/* */
/*Destroy an outline created with @FT_Outline_New. */
/* */
/**/
/*library :: A handle of the library object used to allocate the */
/* outline.*/
/* */
/*outline :: A pointer to the outline object to be discarded.*/
/* */
/* */
/*FreeType error code.0~means success. */
/* */
/* */
/*If the outlines `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_Memorymemory,
FT_Outline*outline );

/*************************************************************************/
/* */
/* */
/*FT_Outline_Check */
/* */
/* */
/*Check the contents of an outline descriptor. */
/* */
/**/
/*outline :: A handle to a source outline. */
/* */
/* */
/*FreeType error code.0~means success. */
/* */
FT_EXPORT( FT_Error )
FT_Outline_Check( FT_Outline*outline );

/*************************************************************************/
/* */
/* */
/*FT_Outline_Get_CBox*/
/* */
/* */
/*Return an outlines `control box.The control box encloses all */
/*the outlines points, including Bzier 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 Bzier 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.*/
/* */
/**/
/*outline :: A pointer to the source outline descriptor. */
/* */
/*

*/
/*acbox :: The outlines control box.*/
/* */
/* */
/*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 );

/*************************************************************************/
/* */
/* */
/*FT_Outline_Translate */
/* */
/* */
/*Apply a simple translation to the points of an outline.*/
/* */
/* */
/*outline :: A pointer to the target outline descriptor. */
/* */
/* */
/*xOffset :: The horizontal offset.*/
/* */
/*yOffset :: The vertical offset.*/
/* */
FT_EXPORT( void )
FT_Outline_Translate( const FT_Outline*outline,
FT_Pos xOffset,
FT_Pos yOffset );

/*************************************************************************/
/* */
/* */
/*FT_Outline_Copy*/
/* */
/* */
/*Copy an outline into another one.Both objects must have the*/
/*same sizes (number of points & number of contours) when this */
/*function is called.*/
/* */
/**/
/*source :: A handle to the source outline.*/
/* */
/*

*/
/*target :: A handle to the target outline.*/
/* */
/* */
/*FreeType error code.0~means success. */
/* */
FT_EXPORT( FT_Error )
FT_Outline_Copy( const FT_Outline*source,
FT_Outline*target );

/*************************************************************************/
/* */
/* */
/*FT_Outline_Transform */
/* */
/* */
/*Apply a simple 22 matrix to all of an outlines points.Useful */
/*for applying rotations, slanting, flipping, etc. */
/* */
/* */
/*outline :: A pointer to the target outline descriptor. */
/* */
/* */
/*matrix:: A pointer to the transformation matrix. */
/* */
/* */
/*You can use @FT_Outline_Translate if you need to translate the */
/*outlines points.*/
/* */
FT_EXPORT( void )
FT_Outline_Transform( const FT_Outline*outline,
const FT_Matrix* matrix );

/*************************************************************************/
/* */
/* */
/*FT_Outline_Embolden*/
/* */
/* */
/*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. */
/* */
/* */
/*outline:: A handle to the target outline.*/
/* */
/* */
/*strength :: How strong the glyph is emboldened.Expressed in*/
/*26.6 pixel format. */
/* */
/* */
/*FreeType error code.0~means success. */
/* */
/* */
/*The used algorithm to increase or decrease the thickness of the*/
/*glyph doesnt 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->glyph->format == FT_GLYPH_FORMAT_OUTLINE )*/
/*FT_Outline_Embolden( &face->glyph->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 );

/*************************************************************************/
/* */
/* */
/*FT_Outline_EmboldenXY*/
/* */
/* */
/*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 );

/*************************************************************************/
/* */
/* */
/*FT_Outline_Reverse */
/* */
/* */
/*Reverse the drawing direction of an outline.This is used to*/
/*ensure consistent fill conventions for mirrored glyphs.*/
/* */
/* */
/*outline :: A pointer to the target outline descriptor. */
/* */
/* */
/*This function toggles the bit flag @FT_OUTLINE_REVERSE_FILL in */
/*the outlines `flags field. */
/* */
/*It shouldnt be used by a normal client application, unless it */
/*knows what it is doing.*/
/* */
FT_EXPORT( void )
FT_Outline_Reverse( FT_Outline*outline );

/*************************************************************************/
/* */
/* */
/*FT_Outline_Get_Bitmap*/
/* */
/* */
/*Render an outline within a bitmap.The outlines image is simply*/
/*OR-ed to the target bitmap.*/
/* */
/**/
/*library :: A handle to a FreeType library object.*/
/* */
/*outline :: A pointer to the source outline descriptor. */
/* */
/* */
/*abitmap :: A pointer to the target bitmap descriptor.*/
/* */
/* */
/*FreeType error code.0~means success. */
/* */
/* */
/*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_Librarylibrary,
FT_Outline* outline,
const FT_Bitmap*abitmap );

/*************************************************************************/
/* */
/* */
/*FT_Outline_Render*/
/* */
/* */
/*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. */
/* */
/**/
/*library :: A handle to a FreeType library object.*/
/* */
/*outline :: A pointer to the source outline descriptor. */
/* */
/* */
/*params:: A pointer to an @FT_Raster_Params structure used to */
/* describe the rendering operation. */
/* */
/* */
/*FreeType error code.0~means success. */
/* */
/* */
/*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 outlines 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 enumFT_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: */