/***************************************************************************/ | |
/* */ | |
/* 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 <ft2build.h> | |
#endif | |
FT_BEGIN_HEADER | |
/*************************************************************************/ | |
/* */ | |
/* <Section> */ | |
/* basic_types */ | |
/* */ | |
/*************************************************************************/ | |
/*************************************************************************/ | |
/* */ | |
/* <Type> */ | |
/* FT_Pos */ | |
/* */ | |
/* <Description> */ | |
/* 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 long FT_Pos; | |
/*************************************************************************/ | |
/* */ | |
/* <Struct> */ | |
/* FT_Vector */ | |
/* */ | |
/* <Description> */ | |
/* A simple structure used to store a 2D vector; coordinates are of */ | |
/* the FT_Pos type. */ | |
/* */ | |
/* <Fields> */ | |
/* x :: The horizontal coordinate. */ | |
/* y :: The vertical coordinate. */ | |
/* */ | |
typedef struct FT_Vector_ | |
{ | |
FT_Pos x; | |
FT_Pos y; | |
} FT_Vector; | |
/*************************************************************************/ | |
/* */ | |
/* <Struct> */ | |
/* FT_BBox */ | |
/* */ | |
/* <Description> */ | |
/* A structure used to hold an outline's bounding box, i.e., the */ | |
/* coordinates of its extrema in the horizontal and vertical */ | |
/* directions. */ | |
/* */ | |
/* <Fields> */ | |
/* xMin :: The horizontal minimum (left-most). */ | |
/* */ | |
/* yMin :: The vertical minimum (bottom-most). */ | |
/* */ | |
/* xMax :: The horizontal maximum (right-most). */ | |
/* */ | |
/* yMax :: The vertical maximum (top-most). */ | |
/* */ | |
/* <Note> */ | |
/* 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 glyph's descender. */ | |
/* Otherwise, the glyph doesn't descend below the baseline. */ | |
/* Similarly, if `ymax' is positive, this value gives the glyph's */ | |
/* ascender. */ | |
/* */ | |
/* `xMin' gives the horizontal distance from the glyph's origin to */ | |
/* the left edge of the glyph's bounding box. If `xMin' is negative, */ | |
/* the glyph extends to the left of the origin. */ | |
/* */ | |
typedef struct FT_BBox_ | |
{ | |
FT_Pos xMin, yMin; | |
FT_Pos xMax, yMax; | |
} FT_BBox; | |
/*************************************************************************/ | |
/* */ | |
/* <Enum> */ | |
/* FT_Pixel_Mode */ | |
/* */ | |
/* <Description> */ | |
/* An enumeration type used to describe the format of pixels in a */ | |
/* given bitmap. Note that additional formats may be added in the */ | |
/* future. */ | |
/* */ | |
/* <Values> */ | |
/* 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 haven't 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 haven't 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 enum FT_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_grays FT_PIXEL_MODE_GRAY | |
#define ft_pixel_mode_pal2 FT_PIXEL_MODE_GRAY2 | |
#define ft_pixel_mode_pal4 FT_PIXEL_MODE_GRAY4 | |
/*************************************************************************/ | |
/* */ | |
/* <Struct> */ | |
/* FT_Bitmap */ | |
/* */ | |
/* <Description> */ | |
/* 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. */ | |
/* */ | |
/* <Fields> */ | |
/* rows :: The number of bitmap rows. */ | |
/* */ | |
/* width :: The number of pixels in bitmap row. */ | |
/* */ | |
/* pitch :: The pitch's 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 application's 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 struct FT_Bitmap_ | |
{ | |
unsigned int rows; | |
unsigned int width; | |
int pitch; | |
unsigned char* buffer; | |
unsigned short num_grays; | |
unsigned char pixel_mode; | |
unsigned char palette_mode; | |
void* palette; | |
} FT_Bitmap; | |
/*************************************************************************/ | |
/* */ | |
/* <Section> */ | |
/* outline_processing */ | |
/* */ | |
/*************************************************************************/ | |
/*************************************************************************/ | |
/* */ | |
/* <Struct> */ | |
/* FT_Outline */ | |
/* */ | |
/* <Description> */ | |
/* This structure is used to describe an outline to the scan-line */ | |
/* converter. */ | |
/* */ | |
/* <Fields> */ | |
/* 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 outline's point coordinates. */ | |
/* */ | |
/* tags :: A pointer to an array of `n_points' chars, giving */ | |
/* each outline point's type. */ | |
/* */ | |
/* If bit~0 is unset, the point is `off' the curve, */ | |
/* i.e., a Bézier control point, while it is `on' if */ | |
/* set. */ | |
/* */ | |
/* Bit~1 is meaningful for `off' points only. If set, */ | |
/* it indicates a third-order Bézier 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. */ | |
/* */ | |
/* <Note> */ | |
/* 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 struct FT_Outline_ | |
{ | |
short n_contours; /* number of contours in glyph */ | |
short n_points; /* number of points in the glyph */ | |
FT_Vector* points; /* the outline's 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_MAX SHRT_MAX | |
#define FT_OUTLINE_POINTS_MAX SHRT_MAX | |
/*************************************************************************/ | |
/* */ | |
/* <Enum> */ | |
/* FT_OUTLINE_XXX */ | |
/* */ | |
/* <Description> */ | |
/* A list of bit-field constants use for the flags in an outline's */ | |
/* `flags' field. */ | |
/* */ | |
/* <Values> */ | |
/* FT_OUTLINE_NONE :: */ | |
/* Value~0 is reserved. */ | |
/* */ | |
/* FT_OUTLINE_OWNER :: */ | |
/* If set, this flag indicates that the outline's 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. */ | |
/* */ | |
/* <Note> */ | |
/* 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_OWNER 0x1 | |
#define FT_OUTLINE_EVEN_ODD_FILL 0x2 | |
#define FT_OUTLINE_REVERSE_FILL 0x4 | |
#define FT_OUTLINE_IGNORE_DROPOUTS 0x8 | |
#define FT_OUTLINE_SMART_DROPOUTS 0x10 | |
#define FT_OUTLINE_INCLUDE_STUBS 0x20 | |
#define FT_OUTLINE_HIGH_PRECISION 0x100 | |
#define FT_OUTLINE_SINGLE_PASS 0x200 | |
/* these constants are deprecated; use the corresponding */ | |
/* `FT_OUTLINE_XXX' values instead */ | |
#define ft_outline_none FT_OUTLINE_NONE | |
#define ft_outline_owner FT_OUTLINE_OWNER | |
#define ft_outline_even_odd_fill FT_OUTLINE_EVEN_ODD_FILL | |
#define ft_outline_reverse_fill FT_OUTLINE_REVERSE_FILL | |
#define ft_outline_ignore_dropouts FT_OUTLINE_IGNORE_DROPOUTS | |
#define ft_outline_high_precision FT_OUTLINE_HIGH_PRECISION | |
#define ft_outline_single_pass FT_OUTLINE_SINGLE_PASS | |
/* */ | |
#define FT_CURVE_TAG( flag ) ( flag & 3 ) | |
#define FT_CURVE_TAG_ON 1 | |
#define FT_CURVE_TAG_CONIC 0 | |
#define FT_CURVE_TAG_CUBIC 2 | |
#define FT_CURVE_TAG_HAS_SCANMODE 4 | |
#define FT_CURVE_TAG_TOUCH_X 8 /* reserved for the TrueType hinter */ | |
#define FT_CURVE_TAG_TOUCH_Y 16 /* 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_Conic FT_CURVE_TAG_CONIC | |
#define FT_Curve_Tag_Cubic FT_CURVE_TAG_CUBIC | |
#define FT_Curve_Tag_Touch_X FT_CURVE_TAG_TOUCH_X | |
#define FT_Curve_Tag_Touch_Y FT_CURVE_TAG_TOUCH_Y | |
/*************************************************************************/ | |
/* */ | |
/* <FuncType> */ | |
/* FT_Outline_MoveToFunc */ | |
/* */ | |
/* <Description> */ | |
/* 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. */ | |
/* */ | |
/* <Input> */ | |
/* 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. */ | |
/* */ | |
/* <Return> */ | |
/* Error code. 0~means success. */ | |
/* */ | |
typedef int | |
(*FT_Outline_MoveToFunc)( const FT_Vector* to, | |
void* user ); | |
#define FT_Outline_MoveTo_Func FT_Outline_MoveToFunc | |
/*************************************************************************/ | |
/* */ | |
/* <FuncType> */ | |
/* FT_Outline_LineToFunc */ | |
/* */ | |
/* <Description> */ | |
/* 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. */ | |
/* */ | |
/* <Input> */ | |
/* 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. */ | |
/* */ | |
/* <Return> */ | |
/* Error code. 0~means success. */ | |
/* */ | |
typedef int | |
(*FT_Outline_LineToFunc)( const FT_Vector* to, | |
void* user ); | |
#define FT_Outline_LineTo_Func FT_Outline_LineToFunc | |
/*************************************************************************/ | |
/* */ | |
/* <FuncType> */ | |
/* FT_Outline_ConicToFunc */ | |
/* */ | |
/* <Description> */ | |
/* 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 Bézier arc in */ | |
/* the outline. */ | |
/* */ | |
/* <Input> */ | |
/* 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. */ | |
/* */ | |
/* <Return> */ | |
/* Error code. 0~means success. */ | |
/* */ | |
typedef int | |
(*FT_Outline_ConicToFunc)( const FT_Vector* control, | |
const FT_Vector* to, | |
void* user ); | |
#define FT_Outline_ConicTo_Func FT_Outline_ConicToFunc | |
/*************************************************************************/ | |
/* */ | |
/* <FuncType> */ | |
/* FT_Outline_CubicToFunc */ | |
/* */ | |
/* <Description> */ | |
/* 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 Bézier arc. */ | |
/* */ | |
/* <Input> */ | |
/* control1 :: A pointer to the first Bézier control point. */ | |
/* */ | |
/* control2 :: A pointer to the second Bézier control point. */ | |
/* */ | |
/* to :: A pointer to the target end point. */ | |
/* */ | |
/* user :: A typeless pointer, which is passed from the caller of */ | |
/* the decomposition function. */ | |
/* */ | |
/* <Return> */ | |
/* 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_Func FT_Outline_CubicToFunc | |
/*************************************************************************/ | |
/* */ | |
/* <Struct> */ | |
/* FT_Outline_Funcs */ | |
/* */ | |
/* <Description> */ | |
/* A structure to hold various function pointers used during outline */ | |
/* decomposition in order to emit segments, conic, and cubic Béziers. */ | |
/* */ | |
/* <Fields> */ | |
/* move_to :: The `move to' emitter. */ | |
/* */ | |
/* line_to :: The segment emitter. */ | |
/* */ | |
/* conic_to :: The second-order Bézier arc emitter. */ | |
/* */ | |
/* cubic_to :: The third-order Bézier 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. */ | |
/* */ | |
/* <Note> */ | |
/* 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 struct FT_Outline_Funcs_ | |
{ | |
FT_Outline_MoveToFunc move_to; | |
FT_Outline_LineToFunc line_to; | |
FT_Outline_ConicToFunc conic_to; | |
FT_Outline_CubicToFunc cubic_to; | |
int shift; | |
FT_Pos delta; | |
} FT_Outline_Funcs; | |
/*************************************************************************/ | |
/* */ | |
/* <Section> */ | |
/* basic_types */ | |
/* */ | |
/*************************************************************************/ | |
/*************************************************************************/ | |
/* */ | |
/* <Macro> */ | |
/* FT_IMAGE_TAG */ | |
/* */ | |
/* <Description> */ | |
/* This macro converts four-letter tags to an unsigned long type. */ | |
/* */ | |
/* <Note> */ | |
/* Since many 16-bit compilers don't 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 */ | |
/*************************************************************************/ | |
/* */ | |
/* <Enum> */ | |
/* FT_Glyph_Format */ | |
/* */ | |
/* <Description> */ | |
/* 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. */ | |
/* */ | |
/* <Values> */ | |
/* 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 Bézier 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 isn't currently capable of rendering */ | |
/* them correctly. */ | |
/* */ | |
typedef enum FT_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_composite FT_GLYPH_FORMAT_COMPOSITE | |
#define ft_glyph_format_bitmap FT_GLYPH_FORMAT_BITMAP | |
#define ft_glyph_format_outline FT_GLYPH_FORMAT_OUTLINE | |
#define ft_glyph_format_plotter FT_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. */ | |
/* */ | |
/*************************************************************************/ | |
/*************************************************************************/ | |
/* */ | |
/* <Section> */ | |
/* raster */ | |
/* */ | |
/* <Title> */ | |
/* Scanline Converter */ | |
/* */ | |
/* <Abstract> */ | |
/* How vectorial outlines are converted into bitmaps and pixmaps. */ | |
/* */ | |
/* <Description> */ | |
/* This section contains technical definitions. */ | |
/* */ | |
/* <Order> */ | |
/* FT_Raster */ | |
/* FT_Span */ | |
/* FT_SpanFunc */ | |
/* */ | |
/* FT_Raster_Params */ | |
/* FT_RASTER_FLAG_XXX */ | |
/* */ | |
/* FT_Raster_NewFunc */ | |
/* FT_Raster_DoneFunc */ | |
/* FT_Raster_ResetFunc */ | |
/* FT_Raster_SetModeFunc */ | |
/* FT_Raster_RenderFunc */ | |
/* FT_Raster_Funcs */ | |
/* */ | |
/*************************************************************************/ | |
/*************************************************************************/ | |
/* */ | |
/* <Type> */ | |
/* FT_Raster */ | |
/* */ | |
/* <Description> */ | |
/* 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; | |
/*************************************************************************/ | |
/* */ | |
/* <Struct> */ | |
/* FT_Span */ | |
/* */ | |
/* <Description> */ | |
/* A structure used to model a single span of gray pixels when */ | |
/* rendering an anti-aliased bitmap. */ | |
/* */ | |
/* <Fields> */ | |
/* x :: The span's horizontal start position. */ | |
/* */ | |
/* len :: The span's length in pixels. */ | |
/* */ | |
/* coverage :: The span color/coverage, ranging from 0 (background) */ | |
/* to 255 (foreground). */ | |
/* */ | |
/* <Note> */ | |
/* 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 struct FT_Span_ | |
{ | |
short x; | |
unsigned short len; | |
unsigned char coverage; | |
} FT_Span; | |
/*************************************************************************/ | |
/* */ | |
/* <FuncType> */ | |
/* FT_SpanFunc */ | |
/* */ | |
/* <Description> */ | |
/* 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. */ | |
/* */ | |
/* <Input> */ | |
/* y :: The scanline's 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. */ | |
/* */ | |
/* <Note> */ | |
/* 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_Func FT_SpanFunc | |
/*************************************************************************/ | |
/* */ | |
/* <FuncType> */ | |
/* FT_Raster_BitTest_Func */ | |
/* */ | |
/* <Description> */ | |
/* Deprecated, unimplemented. */ | |
/* */ | |
typedef int | |
(*FT_Raster_BitTest_Func)( int y, | |
int x, | |
void* user ); | |
/*************************************************************************/ | |
/* */ | |
/* <FuncType> */ | |
/* FT_Raster_BitSet_Func */ | |
/* */ | |
/* <Description> */ | |
/* Deprecated, unimplemented. */ | |
/* */ | |
typedef void | |
(*FT_Raster_BitSet_Func)( int y, | |
int x, | |
void* user ); | |
/*************************************************************************/ | |
/* */ | |
/* <Enum> */ | |
/* FT_RASTER_FLAG_XXX */ | |
/* */ | |
/* <Description> */ | |
/* A list of bit flag constants as used in the `flags' field of a */ | |
/* @FT_Raster_Params structure. */ | |
/* */ | |
/* <Values> */ | |
/* 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 */ | |
/* pixmap's 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_DEFAULT 0x0 | |
#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_default FT_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 | |
/*************************************************************************/ | |
/* */ | |
/* <Struct> */ | |
/* FT_Raster_Params */ | |
/* */ | |
/* <Description> */ | |
/* A structure to hold the arguments used by a raster's render */ | |
/* function. */ | |
/* */ | |
/* <Fields> */ | |
/* 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). */ | |
/* */ | |
/* <Note> */ | |
/* 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 struct FT_Raster_Params_ | |
{ | |
const FT_Bitmap* target; | |
const void* source; | |
int flags; | |
FT_SpanFunc gray_spans; | |
FT_SpanFunc black_spans; /* unused */ | |
FT_Raster_BitTest_Func bit_test; /* unused */ | |
FT_Raster_BitSet_Func bit_set; /* unused */ | |
void* user; | |
FT_BBox clip_box; | |
} FT_Raster_Params; | |
/*************************************************************************/ | |
/* */ | |
/* <FuncType> */ | |
/* FT_Raster_NewFunc */ | |
/* */ | |
/* <Description> */ | |
/* A function used to create a new raster object. */ | |
/* */ | |
/* <Input> */ | |
/* memory :: A handle to the memory allocator. */ | |
/* */ | |
/* <Output> */ | |
/* raster :: A handle to the new raster object. */ | |
/* */ | |
/* <Return> */ | |
/* Error code. 0~means success. */ | |
/* */ | |
/* <Note> */ | |
/* The `memory' parameter is a typeless pointer in order to avoid */ | |
/* un-wanted dependencies on the rest of the FreeType code. In */ | |
/* practice, it is an @FT_Memory object, i.e., a handle to the */ | |
/* standard FreeType memory allocator. However, this field can be */ | |
/* completely ignored by a given raster implementation. */ | |
/* */ | |
typedef int | |
(*FT_Raster_NewFunc)( void* memory, | |
FT_Raster* raster ); | |
#define FT_Raster_New_Func FT_Raster_NewFunc | |
/*************************************************************************/ | |
/* */ | |
/* <FuncType> */ | |
/* FT_Raster_DoneFunc */ | |
/* */ | |
/* <Description> */ | |
/* A function used to destroy a given raster object. */ | |
/* */ | |
/* <Input> */ | |
/* raster :: A handle to the raster object. */ | |
/* */ | |
typedef void | |
(*FT_Raster_DoneFunc)( FT_Raster raster ); | |
#define FT_Raster_Done_Func FT_Raster_DoneFunc | |
/*************************************************************************/ | |
/* */ | |
/* <FuncType> */ | |
/* FT_Raster_ResetFunc */ | |
/* */ | |
/* <Description> */ | |
/* 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. */ | |
/* */ | |
/* <Input> */ | |
/* 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. */ | |
/* */ | |
/* <Note> */ | |
/* 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_Func FT_Raster_ResetFunc | |
/*************************************************************************/ | |
/* */ | |
/* <FuncType> */ | |
/* FT_Raster_SetModeFunc */ | |
/* */ | |
/* <Description> */ | |
/* 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. */ | |
/* */ | |
/* <Input> */ | |
/* 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_Raster raster, | |
unsigned long mode, | |
void* args ); | |
#define FT_Raster_Set_Mode_Func FT_Raster_SetModeFunc | |
/*************************************************************************/ | |
/* */ | |
/* <FuncType> */ | |
/* FT_Raster_RenderFunc */ | |
/* */ | |
/* <Description> */ | |
/* Invoke a given raster to scan-convert a given glyph image into a */ | |
/* target bitmap. */ | |
/* */ | |
/* <Input> */ | |
/* raster :: A handle to the raster object. */ | |
/* */ | |
/* params :: A pointer to an @FT_Raster_Params structure used to */ | |
/* store the rendering parameters. */ | |
/* */ | |
/* <Return> */ | |
/* Error code. 0~means success. */ | |
/* */ | |
/* <Note> */ | |
/* The exact format of the source image depends on the raster's 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 doesn't 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_Raster raster, | |
const FT_Raster_Params* params ); | |
#define FT_Raster_Render_Func FT_Raster_RenderFunc | |
/*************************************************************************/ | |
/* */ | |
/* <Struct> */ | |
/* FT_Raster_Funcs */ | |
/* */ | |
/* <Description> */ | |
/* A structure used to describe a given raster class to the library. */ | |
/* */ | |
/* <Fields> */ | |
/* 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 struct FT_Raster_Funcs_ | |
{ | |
FT_Glyph_Format glyph_format; | |
FT_Raster_NewFunc raster_new; | |
FT_Raster_ResetFunc raster_reset; | |
FT_Raster_SetModeFunc raster_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: */ |