/***************************************************************************/
/* */
/*ftimage.h*/
/* */
/*FreeType glyph image formats and default raster interface*/
/*(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.*/
/* */
/***************************************************************************/
/*************************************************************************/
/* */
/* Note: A `raster is simply a scan-line converter, used to render*/
/* FT_Outlines into FT_Bitmaps.*/
/* */
/*************************************************************************/
#ifndef __FTIMAGE_H__
#define __FTIMAGE_H__
/* _STANDALONE_ is from ftgrays.c */
#ifndef _STANDALONE_
#include
#endif
FT_BEGIN_HEADER
/*************************************************************************/
/* */
/*
/*basic_types*/
/* */
/*************************************************************************/
/*************************************************************************/
/* */
/*
/*FT_Pos */
/* */
/*
/*The type FT_Pos is used to store vectorial coordinates.Depending */
/*on the context, these can represent distances in integer font*/
/*units, or 16.16, or 26.6 fixed-point pixel coordinates.*/
/* */
typedef signed longFT_Pos;
/*************************************************************************/
/* */
/*
/*FT_Vector*/
/* */
/*
/*A simple structure used to store a 2D vector; coordinates are of */
/*the FT_Pos type. */
/* */
/*
/*x :: The horizontal coordinate.*/
/*y :: The vertical coordinate.*/
/* */
typedef structFT_Vector_
{
FT_Posx;
FT_Posy;
} FT_Vector;
/*************************************************************************/
/* */
/*
/*FT_BBox*/
/* */
/*
/*A structure used to hold an outlines bounding box, i.e., the*/
/*coordinates of its extrema in the horizontal and vertical*/
/*directions.*/
/* */
/*
/*xMin :: The horizontal minimum (left-most).*/
/* */
/*yMin :: The vertical minimum (bottom-most).*/
/* */
/*xMax :: The horizontal maximum (right-most). */
/* */
/*yMax :: The vertical maximum (top-most). */
/* */
/*
/*The bounding box is specified with the coordinates of the lower*/
/*left and the upper right corner.In PostScript, those values are*/
/*often called (llx,lly) and (urx,ury), respectively.*/
/* */
/*If `yMin is negative, this value gives the glyphs descender. */
/*Otherwise, the glyph doesnt descend below the baseline. */
/*Similarly, if `ymax is positive, this value gives the glyphs */
/*ascender.*/
/* */
/*`xMin gives the horizontal distance from the glyphs origin to*/
/*the left edge of the glyphs bounding box.If `xMin is negative, */
/*the glyph extends to the left of the origin. */
/* */
typedef structFT_BBox_
{
FT_PosxMin, yMin;
FT_PosxMax, yMax;
} FT_BBox;
/*************************************************************************/
/* */
/*
/*FT_Pixel_Mode*/
/* */
/*
/*An enumeration type used to describe the format of pixels in a */
/*given bitmap.Note that additional formats may be added in the*/
/*future.*/
/* */
/*
/*FT_PIXEL_MODE_NONE ::*/
/*Value~0 is reserved. */
/* */
/*FT_PIXEL_MODE_MONO ::*/
/*A monochrome bitmap, using 1~bit per pixel.Note that pixels*/
/*are stored in most-significant order (MSB), which means that */
/*the left-most pixel in a byte has value 128. */
/* */
/*FT_PIXEL_MODE_GRAY ::*/
/*An 8-bit bitmap, generally used to represent anti-aliased glyph*/
/*images.Each pixel is stored in one byte.Note that the number */
/*of `gray levels is stored in the `num_grays field of the */
/*@FT_Bitmap structure (it generally is 256).*/
/* */
/*FT_PIXEL_MODE_GRAY2 :: */
/*A 2-bit per pixel bitmap, used to represent embedded */
/*anti-aliased bitmaps in font files according to the OpenType */
/*specification.We havent found a single font using this*/
/*format, however. */
/* */
/*FT_PIXEL_MODE_GRAY4 :: */
/*A 4-bit per pixel bitmap, representing embedded anti-aliased */
/*bitmaps in font files according to the OpenType specification. */
/*We havent found a single font using this format, however. */
/* */
/*FT_PIXEL_MODE_LCD :: */
/*An 8-bit bitmap, representing RGB or BGR decimated glyph images*/
/*used for display on LCD displays; the bitmap is three times*/
/*wider than the original glyph image.See also */
/*@FT_RENDER_MODE_LCD. */
/* */
/*FT_PIXEL_MODE_LCD_V :: */
/*An 8-bit bitmap, representing RGB or BGR decimated glyph images*/
/*used for display on rotated LCD displays; the bitmap is three*/
/*times taller than the original glyph image.See also*/
/*@FT_RENDER_MODE_LCD_V. */
/* */
/*FT_PIXEL_MODE_BGRA ::*/
/*An image with four 8-bit channels per pixel, representing a*/
/*color image (such as emoticons) with alpha channel.For each*/
/*pixel, the format is BGRA, which means, the blue channel comes */
/*first in memory.The color channels are pre-multiplied and in */
/*the sRGB colorspace.For example, full red at half-translucent*/
/*opacity will be represented as `00,00,80,80, not `00,00,FF,80. */
/*See also @FT_LOAD_COLOR. */
/* */
typedef enumFT_Pixel_Mode_
{
FT_PIXEL_MODE_NONE = 0,
FT_PIXEL_MODE_MONO,
FT_PIXEL_MODE_GRAY,
FT_PIXEL_MODE_GRAY2,
FT_PIXEL_MODE_GRAY4,
FT_PIXEL_MODE_LCD,
FT_PIXEL_MODE_LCD_V,
FT_PIXEL_MODE_BGRA,
FT_PIXEL_MODE_MAX/* do not remove */
} FT_Pixel_Mode;
/* these constants are deprecated; use the corresponding `FT_Pixel_Mode */
/* values instead. */
#define ft_pixel_mode_none FT_PIXEL_MODE_NONE
#define ft_pixel_mode_mono FT_PIXEL_MODE_MONO
#define ft_pixel_mode_graysFT_PIXEL_MODE_GRAY
#define ft_pixel_mode_pal2 FT_PIXEL_MODE_GRAY2
#define ft_pixel_mode_pal4 FT_PIXEL_MODE_GRAY4
/*************************************************************************/
/* */
/*
/*FT_Bitmap*/
/* */
/*
/*A structure used to describe a bitmap or pixmap to the raster. */
/*Note that we now manage pixmaps of various depths through the*/
/*`pixel_mode field.*/
/* */
/*
/*rows :: The number of bitmap rows. */
/* */
/*width:: The number of pixels in bitmap row.*/
/* */
/*pitch:: The pitchs absolute value is the number of bytes*/
/*taken by one bitmap row, including padding.*/
/*However, the pitch is positive when the bitmap has */
/*a `down flow, and negative when it has an `up*/
/*flow.In all cases, the pitch is an offset to add */
/*to a bitmap pointer in order to go down one row. */
/* */
/*Note that `padding means the alignment of a */
/*bitmap to a byte border, and FreeType functions*/
/*normally align to the smallest possible integer*/
/*value. */
/* */
/*For the B/W rasterizer, `pitch is always an even*/
/*number.*/
/* */
/*To change the pitch of a bitmap (say, to make it a */
/*multiple of 4), use @FT_Bitmap_Convert.*/
/*Alternatively, you might use callback functions to */
/*directly render to the applications surface; see*/
/*the file `example2.cpp in the tutorial for a*/
/*demonstration. */
/* */
/*buffer :: A typeless pointer to the bitmap buffer.This */
/*value should be aligned on 32-bit boundaries in*/
/*most cases.*/
/* */
/*num_grays:: This field is only used with */
/*@FT_PIXEL_MODE_GRAY; it gives the number of gray */
/*levels used in the bitmap. */
/* */
/*pixel_mode :: The pixel mode, i.e., how pixel bits are stored. */
/*See @FT_Pixel_Mode for possible values.*/
/* */
/*palette_mode :: This field is intended for paletted pixel modes; */
/*it indicates how the palette is stored.Not */
/*used currently.*/
/* */
/*palette:: A typeless pointer to the bitmap palette; this */
/*field is intended for paletted pixel modes.Not */
/*used currently.*/
/* */
typedef structFT_Bitmap_
{
unsigned introws;
unsigned intwidth;
int pitch;
unsigned char*buffer;
unsigned shortnum_grays;
unsigned char pixel_mode;
unsigned char palette_mode;
void* palette;
} FT_Bitmap;
/*************************************************************************/
/* */
/*
/*outline_processing */
/* */
/*************************************************************************/
/*************************************************************************/
/* */
/*
/*FT_Outline */
/* */
/*
/*This structure is used to describe an outline to the scan-line */
/*converter. */
/* */
/*
/*n_contours :: The number of contours in the outline. */
/* */
/*n_points :: The number of points in the outline. */
/* */
/*points :: A pointer to an array of `n_points @FT_Vector */
/*elements, giving the outlines point coordinates.*/
/* */
/*tags :: A pointer to an array of `n_points chars, giving*/
/*each outline points type. */
/* */
/*If bit~0 is unset, the point is `off the curve, */
/*i.e., a Bzier control point, while it is `on if*/
/*set. */
/* */
/*Bit~1 is meaningful for `off points only.If set,*/
/*it indicates a third-order Bzier arc control point; */
/*and a second-order control point if unset. */
/* */
/*If bit~2 is set, bits 5-7 contain the drop-out mode*/
/*(as defined in the OpenType specification; the value */
/*is the same as the argument to the SCANMODE*/
/*instruction).*/
/* */
/*Bits 3 and~4 are reserved for internal purposes. */
/* */
/*contours :: An array of `n_contours shorts, giving the end*/
/*point of each contour within the outline.For */
/*example, the first contour is defined by the points*/
/*`0 to `contours[0], the second one is defined by */
/*the points `contours[0]+1 to `contours[1], etc.*/
/* */
/*flags:: A set of bit flags used to characterize the outline*/
/*and give hints to the scan-converter and hinter on */
/*how to convert/grid-fit it.See @FT_OUTLINE_XXX.*/
/* */
/*
/*The B/W rasterizer only checks bit~2 in the `tags array for the */
/*first point of each contour.The drop-out mode as given with*/
/*@FT_OUTLINE_IGNORE_DROPOUTS, @FT_OUTLINE_SMART_DROPOUTS, and */
/*@FT_OUTLINE_INCLUDE_STUBS in `flags is then overridden. */
/* */
typedef structFT_Outline_
{
short n_contours;/* number of contours in glyph*/
short n_points;/* number of points in the glyph*/
FT_Vector*points;/* the outlines points */
char* tags;/* the points flags */
short*contours;/* the contour end points */
int flags; /* outline masks*/
} FT_Outline;
/* */
/* Following limits must be consistent with */
/* FT_Outline.{n_contours,n_points} */
#define FT_OUTLINE_CONTOURS_MAXSHRT_MAX
#define FT_OUTLINE_POINTS_MAXSHRT_MAX
/*************************************************************************/
/* */
/*
/*FT_OUTLINE_XXX */
/* */
/*
/*A list of bit-field constants use for the flags in an outlines*/
/*`flags field. */
/* */
/*
/*FT_OUTLINE_NONE :: */
/*Value~0 is reserved. */
/* */
/*FT_OUTLINE_OWNER ::*/
/*If set, this flag indicates that the outlines field arrays*/
/*(i.e., `points, `flags, and `contours) are `owned by the */
/*outline object, and should thus be freed when it is destroyed. */
/* */
/*FT_OUTLINE_EVEN_ODD_FILL ::*/
/*By default, outlines are filled using the non-zero winding rule. */
/*If set to 1, the outline will be filled using the even-odd fill*/
/*rule (only works with the smooth rasterizer).*/
/* */
/*FT_OUTLINE_REVERSE_FILL :: */
/*By default, outside contours of an outline are oriented in */
/*clock-wise direction, as defined in the TrueType specification.*/
/*This flag is set if the outline uses the opposite direction*/
/*(typically for Type~1 fonts).This flag is ignored by the scan*/
/*converter. */
/* */
/*FT_OUTLINE_IGNORE_DROPOUTS ::*/
/*By default, the scan converter will try to detect drop-outs in */
/*an outline and correct the glyph bitmap to ensure consistent */
/*shape continuity.If set, this flag hints the scan-line */
/*converter to ignore such cases.See below for more information. */
/* */
/*FT_OUTLINE_SMART_DROPOUTS :: */
/*Select smart dropout control.If unset, use simple dropout*/
/*control.Ignored if @FT_OUTLINE_IGNORE_DROPOUTS is set.See*/
/*below for more information.*/
/* */
/*FT_OUTLINE_INCLUDE_STUBS ::*/
/*If set, turn pixels on for `stubs, otherwise exclude them.*/
/*Ignored if @FT_OUTLINE_IGNORE_DROPOUTS is set.See below for*/
/*more information.*/
/* */
/*FT_OUTLINE_HIGH_PRECISION :: */
/*This flag indicates that the scan-line converter should try to */
/*convert this outline to bitmaps with the highest possible*/
/*quality.It is typically set for small character sizes.Note */
/*that this is only a hint that might be completely ignored by a */
/*given scan-converter.*/
/* */
/*FT_OUTLINE_SINGLE_PASS ::*/
/*This flag is set to force a given scan-converter to only use a */
/*single pass over the outline to render a bitmap glyph image. */
/*Normally, it is set for very large character sizes.It is only*/
/*a hint that might be completely ignored by a given */
/*scan-converter.*/
/* */
/*
/*The flags @FT_OUTLINE_IGNORE_DROPOUTS, @FT_OUTLINE_SMART_DROPOUTS, */
/*and @FT_OUTLINE_INCLUDE_STUBS are ignored by the smooth*/
/*rasterizer.*/
/* */
/*There exists a second mechanism to pass the drop-out mode to the */
/*B/W rasterizer; see the `tags field in @FT_Outline. */
/* */
/*Please refer to the description of the `SCANTYPE instruction in */
/*the OpenType specification (in file `ttinst1.doc) how simple*/
/*drop-outs, smart drop-outs, and stubs are defined. */
/* */
#define FT_OUTLINE_NONE 0x0
#define FT_OUTLINE_OWNER0x1
#define FT_OUTLINE_EVEN_ODD_FILL0x2
#define FT_OUTLINE_REVERSE_FILL 0x4
#define FT_OUTLINE_IGNORE_DROPOUTS0x8
#define FT_OUTLINE_SMART_DROPOUTS 0x10
#define FT_OUTLINE_INCLUDE_STUBS0x20
#define FT_OUTLINE_HIGH_PRECISION 0x100
#define FT_OUTLINE_SINGLE_PASS0x200
/* these constants are deprecated; use the corresponding */
/* `FT_OUTLINE_XXX values instead */
#define ft_outline_none FT_OUTLINE_NONE
#define ft_outline_ownerFT_OUTLINE_OWNER
#define ft_outline_even_odd_fillFT_OUTLINE_EVEN_ODD_FILL
#define ft_outline_reverse_fill FT_OUTLINE_REVERSE_FILL
#define ft_outline_ignore_dropoutsFT_OUTLINE_IGNORE_DROPOUTS
#define ft_outline_high_precision FT_OUTLINE_HIGH_PRECISION
#define ft_outline_single_passFT_OUTLINE_SINGLE_PASS
/* */
#define FT_CURVE_TAG( flag )( flag & 3 )
#define FT_CURVE_TAG_ON1
#define FT_CURVE_TAG_CONIC 0
#define FT_CURVE_TAG_CUBIC 2
#define FT_CURVE_TAG_HAS_SCANMODE4
#define FT_CURVE_TAG_TOUCH_X 8/* reserved for the TrueType hinter */
#define FT_CURVE_TAG_TOUCH_Y16/* reserved for the TrueType hinter */
#define FT_CURVE_TAG_TOUCH_BOTH( FT_CURVE_TAG_TOUCH_X |
FT_CURVE_TAG_TOUCH_Y )
#define FT_Curve_Tag_On FT_CURVE_TAG_ON
#define FT_Curve_Tag_ConicFT_CURVE_TAG_CONIC
#define FT_Curve_Tag_CubicFT_CURVE_TAG_CUBIC
#define FT_Curve_Tag_Touch_XFT_CURVE_TAG_TOUCH_X
#define FT_Curve_Tag_Touch_YFT_CURVE_TAG_TOUCH_Y
/*************************************************************************/
/* */
/*
/*FT_Outline_MoveToFunc*/
/* */
/*
/*A function pointer type used to describe the signature of a `move*/
/*to function during outline walking/decomposition. */
/* */
/*A `move to is emitted to start a new contour in an outline. */
/* */
/**/
/*to :: A pointer to the target point of the `move to.*/
/* */
/*user :: A typeless pointer, which is passed from the caller of the */
/*decomposition function.*/
/* */
/*
/*Error code.0~means success.*/
/* */
typedef int
(*FT_Outline_MoveToFunc)( const FT_Vector*to,
void* user );
#define FT_Outline_MoveTo_FuncFT_Outline_MoveToFunc
/*************************************************************************/
/* */
/*
/*FT_Outline_LineToFunc*/
/* */
/*
/*A function pointer type used to describe the signature of a `line*/
/*to function during outline walking/decomposition. */
/* */
/*A `line to is emitted to indicate a segment in the outline. */
/* */
/**/
/*to :: A pointer to the target point of the `line to.*/
/* */
/*user :: A typeless pointer, which is passed from the caller of the */
/*decomposition function.*/
/* */
/*
/*Error code.0~means success.*/
/* */
typedef int
(*FT_Outline_LineToFunc)( const FT_Vector*to,
void* user );
#define FT_Outline_LineTo_FuncFT_Outline_LineToFunc
/*************************************************************************/
/* */
/*
/*FT_Outline_ConicToFunc */
/* */
/*
/*A function pointer type used to describe the signature of a `conic */
/*to function during outline walking or decomposition.*/
/* */
/*A `conic to is emitted to indicate a second-order Bzier arc in */
/*the outline. */
/* */
/**/
/*control :: An intermediate control point between the last position */
/* and the new target in `to. */
/* */
/*to:: A pointer to the target end point of the conic arc. */
/* */
/*user:: A typeless pointer, which is passed from the caller of*/
/* the decomposition function. */
/* */
/*
/*Error code.0~means success.*/
/* */
typedef int
(*FT_Outline_ConicToFunc)( const FT_Vector*control,
const FT_Vector*to,
void* user );
#define FT_Outline_ConicTo_FuncFT_Outline_ConicToFunc
/*************************************************************************/
/* */
/*
/*FT_Outline_CubicToFunc */
/* */
/*
/*A function pointer type used to describe the signature of a `cubic */
/*to function during outline walking or decomposition.*/
/* */
/*A `cubic to is emitted to indicate a third-order Bzier arc.*/
/* */
/**/
/*control1 :: A pointer to the first Bzier control point. */
/* */
/*control2 :: A pointer to the second Bzier control point.*/
/* */
/*to :: A pointer to the target end point. */
/* */
/*user :: A typeless pointer, which is passed from the caller of */
/*the decomposition function.*/
/* */
/*
/*Error code.0~means success.*/
/* */
typedef int
(*FT_Outline_CubicToFunc)( const FT_Vector*control1,
const FT_Vector*control2,
const FT_Vector*to,
void* user );
#define FT_Outline_CubicTo_FuncFT_Outline_CubicToFunc
/*************************************************************************/
/* */
/*
/*FT_Outline_Funcs */
/* */
/*
/*A structure to hold various function pointers used during outline*/
/*decomposition in order to emit segments, conic, and cubic Bziers. */
/* */
/*
/*move_to:: The `move to emitter. */
/* */
/*line_to:: The segment emitter. */
/* */
/*conic_to :: The second-order Bzier arc emitter. */
/* */
/*cubic_to :: The third-order Bzier arc emitter.*/
/* */
/*shift:: The shift that is applied to coordinates before they */
/*are sent to the emitter. */
/* */
/*delta:: The delta that is applied to coordinates before they */
/*are sent to the emitter, but after the shift.*/
/* */
/*
/*The point coordinates sent to the emitters are the transformed */
/*version of the original coordinates (this is important for high*/
/*accuracy during scan-conversion).The transformation is simple: */
/* */
/*{*/
/*x = (x << shift) – delta*//*y’ = (x << shift) – delta*//*}*//* *//*Set the values of `shift’ and `delta’ to~0 to get the original *//*point coordinates. *//* */typedef structFT_Outline_Funcs_{FT_Outline_MoveToFunc move_to;FT_Outline_LineToFunc line_to;FT_Outline_ConicToFuncconic_to;FT_Outline_CubicToFunccubic_to;int shift;FT_Posdelta;} FT_Outline_Funcs;/*************************************************************************//* *//*
/*basic_types*/
/* */
/*************************************************************************/
/*************************************************************************/
/* */
/*
/*FT_IMAGE_TAG */
/* */
/*
/*This macro converts four-letter tags to an unsigned long type. */
/* */
/*
/*Since many 16-bit compilers dont like 32-bit enumerations, you*/
/*should redefine this macro in case of problems to something like */
/*this:*/
/* */
/*{*/
/*#define FT_IMAGE_TAG( value, _x1, _x2, _x3, _x4 )value */
/*}*/
/* */
/*to get a simple enumeration without assigning special numbers. */
/* */
#ifndef FT_IMAGE_TAG
#define FT_IMAGE_TAG( value, _x1, _x2, _x3, _x4 )
value = ( ( (unsigned long)_x1 << 24 ) | ( (unsigned long)_x2 << 16 ) | ( (unsigned long)_x3 << 8) | (unsigned long)_x4 )#endif /* FT_IMAGE_TAG *//*************************************************************************//* *//*
/*FT_Glyph_Format*/
/* */
/*
/*An enumeration type used to describe the format of a given glyph */
/*image.Note that this version of FreeType only supports two image */
/*formats, even though future font drivers will be able to register*/
/*their own format.*/
/* */
/*
/*FT_GLYPH_FORMAT_NONE ::*/
/*The value~0 is reserved. */
/* */
/*FT_GLYPH_FORMAT_COMPOSITE :: */
/*The glyph image is a composite of several other images.This*/
/*format is _only_ used with @FT_LOAD_NO_RECURSE, and is used to */
/*report compound glyphs (like accented characters). */
/* */
/*FT_GLYPH_FORMAT_BITMAP ::*/
/*The glyph image is a bitmap, and can be described as an*/
/*@FT_Bitmap.You generally need to access the `bitmap field of*/
/*the @FT_GlyphSlotRec structure to read it. */
/* */
/*FT_GLYPH_FORMAT_OUTLINE :: */
/*The glyph image is a vectorial outline made of line segments */
/*and Bzier arcs; it can be described as an @FT_Outline; you*/
/*generally want to access the `outline field of the*/
/*@FT_GlyphSlotRec structure to read it. */
/* */
/*FT_GLYPH_FORMAT_PLOTTER :: */
/*The glyph image is a vectorial path with no inside and outside */
/*contours.Some Type~1 fonts, like those in the Hershey family,*/
/*contain glyphs in this format.These are described as */
/*@FT_Outline, but FreeType isnt currently capable of rendering */
/*them correctly.*/
/* */
typedef enumFT_Glyph_Format_
{
FT_IMAGE_TAG( FT_GLYPH_FORMAT_NONE, 0, 0, 0, 0 ),
FT_IMAGE_TAG( FT_GLYPH_FORMAT_COMPOSITE, c, o, m, p ),
FT_IMAGE_TAG( FT_GLYPH_FORMAT_BITMAP,b, i, t, s ),
FT_IMAGE_TAG( FT_GLYPH_FORMAT_OUTLINE, o, u, t, l ),
FT_IMAGE_TAG( FT_GLYPH_FORMAT_PLOTTER, p, l, o, t )
} FT_Glyph_Format;
/* these constants are deprecated; use the corresponding */
/* `FT_Glyph_Format values instead. */
#define ft_glyph_format_none FT_GLYPH_FORMAT_NONE
#define ft_glyph_format_compositeFT_GLYPH_FORMAT_COMPOSITE
#define ft_glyph_format_bitmap FT_GLYPH_FORMAT_BITMAP
#define ft_glyph_format_outlineFT_GLYPH_FORMAT_OUTLINE
#define ft_glyph_format_plotterFT_GLYPH_FORMAT_PLOTTER
/*************************************************************************/
/*************************************************************************/
/*************************************************************************/
/***** *****/
/*****R A S T E R D E F I N I T I O N S*****/
/***** *****/
/*************************************************************************/
/*************************************************************************/
/*************************************************************************/
/*************************************************************************/
/* */
/* A raster is a scan converter, in charge of rendering an outline into*/
/* a a bitmap.This section contains the public API for rasters.*/
/* */
/* Note that in FreeType 2, all rasters are now encapsulated within*/
/* specific modules called `renderers.See `ftrender.h for more */
/* details on renderers. */
/* */
/*************************************************************************/
/*************************************************************************/
/* */
/*
/*raster */
/* */
/*
/*************************************************************************/
/* */
/*
/*FT_Raster*/
/* */
/*
/*An opaque handle (pointer) to a raster object.Each object can be */
/*used independently to convert an outline into a bitmap or pixmap.*/
/* */
typedef struct FT_RasterRec_*FT_Raster;
/*************************************************************************/
/* */
/*
/*FT_Span*/
/* */
/*
/*A structure used to model a single span of gray pixels when*/
/*rendering an anti-aliased bitmap.*/
/* */
/*
/*x:: The spans horizontal start position.*/
/* */
/*len:: The spans length in pixels. */
/* */
/*coverage :: The span color/coverage, ranging from 0 (background) */
/*to 255 (foreground). */
/* */
/*
/*This structure is used by the span drawing callback type named */
/*@FT_SpanFunc that takes the y~coordinate of the span as a*/
/*parameter. */
/* */
/*The coverage value is always between 0 and 255.If you want less*/
/*gray values, the callback function has to reduce them. */
/* */
typedef structFT_Span_
{
short x;
unsigned shortlen;
unsigned char coverage;
} FT_Span;
/*************************************************************************/
/* */
/*
/*FT_SpanFunc*/
/* */
/*
/*A function used as a call-back by the anti-aliased renderer in */
/*order to let client applications draw themselves the gray pixel*/
/*spans on each scan line. */
/* */
/**/
/*y :: The scanlines y~coordinate.*/
/* */
/*count :: The number of spans to draw on this scanline. */
/* */
/*spans :: A table of `count spans to draw on the scanline. */
/* */
/*user:: User-supplied data that is passed to the callback.*/
/* */
/*
/*This callback allows client applications to directly render the*/
/*gray spans of the anti-aliased bitmap to any kind of surfaces. */
/* */
/*This can be used to write anti-aliased outlines directly to a*/
/*given background bitmap, and even perform translucency.*/
/* */
/*Note that the `count field cannot be greater than a fixed value */
/*defined by the `FT_MAX_GRAY_SPANS configuration macro in*/
/*`ftoption.h.By default, this value is set to~32, which means*/
/*that if there are more than 32~spans on a given scanline, the*/
/*callback is called several times with the same `y parameter in*/
/*order to draw all callbacks. */
/* */
/*Otherwise, the callback is only called once per scan-line, and */
/*only for those scanlines that do have `gray pixels on them. */
/* */
typedef void
(*FT_SpanFunc)( int y,
int count,
const FT_Span*spans,
void* user );
#define FT_Raster_Span_FuncFT_SpanFunc
/*************************************************************************/
/* */
/*
/*FT_Raster_BitTest_Func */
/* */
/*
/*Deprecated, unimplemented. */
/* */
typedef int
(*FT_Raster_BitTest_Func)( inty,
intx,
void*user );
/*************************************************************************/
/* */
/*
/*FT_Raster_BitSet_Func*/
/* */
/*
/*Deprecated, unimplemented. */
/* */
typedef void
(*FT_Raster_BitSet_Func)( inty,
intx,
void*user );
/*************************************************************************/
/* */
/*
/*FT_RASTER_FLAG_XXX */
/* */
/*
/*A list of bit flag constants as used in the `flags field of a */
/*@FT_Raster_Params structure. */
/* */
/*
/*FT_RASTER_FLAG_DEFAULT :: This value is 0. */
/* */
/*FT_RASTER_FLAG_AA:: This flag is set to indicate that an */
/*anti-aliased glyph image should be */
/*generated.Otherwise, it will be*/
/*monochrome (1-bit).*/
/* */
/*FT_RASTER_FLAG_DIRECT:: This flag is set to indicate direct*/
/*rendering.In this mode, client */
/*applications must provide their own span */
/*callback.This lets them directly */
/*draw or compose over an existing bitmap. */
/*If this bit is not set, the target */
/*pixmaps buffer _must_ be zeroed before*/
/*rendering. */
/* */
/*Direct rendering is only possible with */
/*anti-aliased glyphs. */
/* */
/*FT_RASTER_FLAG_CLIP:: This flag is only used in direct */
/*rendering mode.If set, the output will */
/*be clipped to a box specified in the */
/*`clip_box field of the*/
/*@FT_Raster_Params structure. */
/* */
/*Note that by default, the glyph bitmap */
/*is clipped to the target pixmap, except*/
/*in direct rendering mode where all spans */
/*are generated if no clipping box is set. */
/* */
#define FT_RASTER_FLAG_DEFAULT0x0
#define FT_RASTER_FLAG_AA 0x1
#define FT_RASTER_FLAG_DIRECT 0x2
#define FT_RASTER_FLAG_CLIP 0x4
/* these constants are deprecated; use the corresponding */
/* `FT_RASTER_FLAG_XXX values instead */
#define ft_raster_flag_defaultFT_RASTER_FLAG_DEFAULT
#define ft_raster_flag_aa FT_RASTER_FLAG_AA
#define ft_raster_flag_direct FT_RASTER_FLAG_DIRECT
#define ft_raster_flag_clip FT_RASTER_FLAG_CLIP
/*************************************************************************/
/* */
/*
/*FT_Raster_Params */
/* */
/*
/*A structure to hold the arguments used by a rasters render*/
/*function.*/
/* */
/*
/*target:: The target bitmap.*/
/* */
/*source:: A pointer to the source glyph image (e.g., an */
/* @FT_Outline). */
/* */
/*flags :: The rendering flags.*/
/* */
/*gray_spans:: The gray span drawing callback. */
/* */
/*black_spans :: Unused. */
/* */
/*bit_test:: Unused. */
/* */
/*bit_set :: Unused. */
/* */
/*user:: User-supplied data that is passed to each drawing */
/* callback. */
/* */
/*clip_box:: An optional clipping box.It is only used in */
/* direct rendering mode.Note that coordinates here*/
/* should be expressed in _integer_ pixels (and not in */
/* 26.6 fixed-point units).*/
/* */
/*
/*An anti-aliased glyph bitmap is drawn if the @FT_RASTER_FLAG_AA*/
/*bit flag is set in the `flags field, otherwise a monochrome */
/*bitmap is generated. */
/* */
/*If the @FT_RASTER_FLAG_DIRECT bit flag is set in `flags, the*/
/*raster will call the `gray_spans callback to draw gray pixel*/
/*spans.This allows direct composition over a pre-existing bitmap*/
/*through user-provided callbacks to perform the span drawing and*/
/*composition.Not supported by the monochrome rasterizer.*/
/* */
typedef structFT_Raster_Params_
{
const FT_Bitmap*target;
const void* source;
int flags;
FT_SpanFunc gray_spans;
FT_SpanFunc black_spans;/* unused */
FT_Raster_BitTest_Funcbit_test; /* unused */
FT_Raster_BitSet_Func bit_set;/* unused */
void* user;
FT_BBox clip_box;
} FT_Raster_Params;
/*************************************************************************/
/* */
/*
/*FT_Raster_NewFunc*/
/* */
/*
/*A function used to create a new raster object. */
/* */
/**/
/*memory :: A handle to the memory allocator.*/
/* */
/*
#define FT_Raster_New_FuncFT_Raster_NewFunc
/*************************************************************************/
/* */
/*
/*FT_Raster_DoneFunc */
/* */
/*
/*A function used to destroy a given raster object.*/
/* */
/**/
/*raster :: A handle to the raster object. */
/* */
typedef void
(*FT_Raster_DoneFunc)( FT_Rasterraster );
#define FT_Raster_Done_FuncFT_Raster_DoneFunc
/*************************************************************************/
/* */
/*
/*FT_Raster_ResetFunc*/
/* */
/*
/*FreeType used to provide an area of memory called the `render*/
/*pool available to all registered rasters.This was not thread*/
/*safe however and now FreeType never allocates this pool.NULL */
/*is always passed in as pool_base.*/
/* */
/*This function is called each time the render pool changes, or just */
/*after a new raster object is created.*/
/* */
/**/
/*raster:: A handle to the new raster object.*/
/* */
/*pool_base :: The address in memory of the render pool. */
/* */
/*pool_size :: The size in bytes of the render pool. */
/* */
/*
/*Rasters should ignore the render pool and rely on dynamic or stack */
/*allocation if they want to (a handle to the memory allocator is*/
/*passed to the raster constructor). */
/* */
typedef void
(*FT_Raster_ResetFunc)( FT_Raster raster,
unsigned char*pool_base,
unsigned long pool_size );
#define FT_Raster_Reset_FuncFT_Raster_ResetFunc
/*************************************************************************/
/* */
/*
/*FT_Raster_SetModeFunc*/
/* */
/*
/*This function is a generic facility to change modes or attributes*/
/*in a given raster.This can be used for debugging purposes, or*/
/*simply to allow implementation-specific `features in a given*/
/*raster module. */
/* */
/**/
/*raster :: A handle to the new raster object. */
/* */
/*mode :: A 4-byte tag used to name the mode or property.*/
/* */
/*args :: A pointer to the new mode/property to use. */
/* */
typedef int
(*FT_Raster_SetModeFunc)( FT_Rasterraster,
unsigned longmode,
void*args );
#define FT_Raster_Set_Mode_FuncFT_Raster_SetModeFunc
/*************************************************************************/
/* */
/*
/*FT_Raster_RenderFunc */
/* */
/*
/*Invoke a given raster to scan-convert a given glyph image into a */
/*target bitmap. */
/* */
/**/
/*raster :: A handle to the raster object. */
/* */
/*params :: A pointer to an @FT_Raster_Params structure used to*/
/*store the rendering parameters.*/
/* */
/*
/*Error code.0~means success.*/
/* */
/*
/*The exact format of the source image depends on the rasters glyph */
/*format defined in its @FT_Raster_Funcs structure.It can be an*/
/*@FT_Outline or anything else in order to support a large array of*/
/*glyph formats. */
/* */
/*Note also that the render function can fail and return a */
/*`FT_Err_Unimplemented_Feature error code if the raster used does*/
/*not support direct composition.*/
/* */
/*XXX: For now, the standard raster doesnt support direct */
/* composition but this should change for the final release (see */
/* the files `demos/src/ftgrays.c and `demos/src/ftgrays2.c*/
/* for examples of distinct implementations that support direct*/
/* composition). */
/* */
typedef int
(*FT_Raster_RenderFunc)( FT_Rasterraster,
const FT_Raster_Params*params );
#define FT_Raster_Render_FuncFT_Raster_RenderFunc
/*************************************************************************/
/* */
/*
/*FT_Raster_Funcs*/
/* */
/*
/* A structure used to describe a given raster class to the library. */
/* */
/*
/*glyph_format:: The supported glyph format for this raster. */
/* */
/*raster_new:: The raster constructor. */
/* */
/*raster_reset:: Used to reset the render pool within the raster.*/
/* */
/*raster_render :: A function to render a glyph into a given bitmap. */
/* */
/*raster_done :: The raster destructor.*/
/* */
typedef structFT_Raster_Funcs_
{
FT_Glyph_Formatglyph_format;
FT_Raster_NewFuncraster_new;
FT_Raster_ResetFuncraster_reset;
FT_Raster_SetModeFuncraster_set_mode;
FT_Raster_RenderFunc raster_render;
FT_Raster_DoneFunc raster_done;
} FT_Raster_Funcs;
/* */
FT_END_HEADER
#endif /* __FTIMAGE_H__ */
/* END */
/* Local Variables: */
/* coding: utf-8*/
/* End: */
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