| /***************************************************************************/ |
| /* */ |
| /* 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: */ |
