kc3-lang/freetype/include/ftimage.h
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Hash : c136b409
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Date : 2000-05-04T17:24:54
an update to FT_Outline_Funcs used to improve the accuracy of outline decomposition
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include/ftimage.h
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/***************************************************************************/ /* */ /* ftimage.h */ /* */ /* This file defines the glyph image formats recognized by FreeType, as */ /* well as the default raster interface. */ /* */ /* Copyright 1996-1999 by */ /* David Turner, Robert Wilhelm, and Werner Lemberg */ /* */ /* This file is part of the FreeType project, and may only be used */ /* modified and distributed under the terms of the FreeType project */ /* license, LICENSE.TXT. By continuing to use, modify, or distribute */ /* this file you indicate that you have read the license and */ /* understand and accept it fully. */ /* */ /***************************************************************************/ #ifndef FTIMAGE_H #define FTIMAGE_H /*************************************************************************/ /* */ /* <Type> */ /* FT_Pos */ /* */ /* <Description> */ /* The type FT_Pos is a 32-bit integer used to store vectorial */ /* coordinates. Depending on the context, these can represent */ /* distances in integer font units, or 26.6 fixed float 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; /************************************************************************* * * <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. * * <Fields> * ft_pixel_mode_mono :: a monochrome bitmap (1 bit/pixel) * * ft_pixel_mode_grays :: an 8-bit gray-levels bitmap. Note that * the total number of gray levels is given * in the `num_grays' field of the FT_Bitmap * structure. * * ft_pixel_mode_pal2 :: a 2-bit paletted bitmap. * currently unused by FreeType. * * ft_pixel_mode_pal4 :: a 4-bit paletted bitmap. * currently unused by FreeType. * * ft_pixel_mode_pal8 :: an 8-bit paletted bitmap. * currently unused by FreeType. * * ft_pixel_mode_rgb15 :: a 15-bit RGB bitmap. Uses 5:5:5 encoding * currently unused by FreeType. * * ft_pixel_mode_rgb16 :: a 16-bit RGB bitmap. Uses 5:6:5 encoding * currently unused by FreeType. * * ft_pixel_mode_rgb24 :: a 24-bit RGB bitmap. * currently unused by FreeType. * * ft_pixel_mode_rgb32 :: a 32-bit RGB bitmap. * currently unused by FreeType. * * <Note> * Some anti-aliased bitmaps might be embedded in TrueType fonts * using formats pal2 or pal4, though no fonts presenting those * have been found to date.. * *************************************************************************/ typedef enum FT_Pixel_Mode_ { ft_pixel_mode_none = 0, ft_pixel_mode_mono, ft_pixel_mode_grays, ft_pixel_mode_pal2, ft_pixel_mode_pal4, ft_pixel_mode_pal8, ft_pixel_mode_rgb15, ft_pixel_mode_rgb16, ft_pixel_mode_rgb24, ft_pixel_mode_rgb32, ft_pixel_mode_max /* do not remove */ } FT_Pixel_Mode; /************************************************************************* * * <Enum> * FT_Palette_Mode * * <Description> * An enumeration type used to describe the format of a bitmap * palette, used with ft_pixel_mode_pal4 and ft_pixel_mode_pal8 * * <Fields> * ft_palette_mode_rgb :: the palette is an array of 3-bytes RGB records * * ft_palette_mode_rgba :: the palette is an array of 4-bytes RGBA records * * <Note> * As ft_pixel_mode_pal2, pal4 and pal8 are currently unused by * FreeType, these types are not handled by the library itself. * *************************************************************************/ typedef enum FT_Palette_Mode_ { ft_palette_mode_rgb = 0, ft_palette_mode_rgba, ft_palettte_mode_max /* do not remove */ } FT_Palette_Mode; /************************************************************************* * * <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. * * 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_grays, * it gives the number of gray levels used in the * bitmap. * * pixel_mode :: the pixel_mode, i.e. how pixel bits are stored * * palette_mode :: this field is only used with paletted pixel modes, * it indicates how the palette is stored * * palette :: a typeless pointer to the bitmap palette. only used * for paletted pixel modes. * * <Note> * When using pixel modes pal2, pal4 and pal8 with a void `palette' * field, a gray pixmap with respectively 4, 16 and 256 levels of gray * is assumed. This, in order to be compatible with some embedded bitmap * formats defined in the TrueType spec. * * Note that no font was found presenting such embedded bitmaps, so this * is currently completely unhandled by the library. * * *************************************************************************/ typedef struct FT_Bitmap_ { int rows; int width; int pitch; void* buffer; short num_grays; char pixel_mode; char palette_mode; void* palette; } FT_Bitmap; /*************************************************************************/ /* */ /* <Struct> */ /* FT_Outline */ /* */ /* <Description> */ /* This structure is used to describe an outline to the scan-line */ /* converter. It's a copy of the TT_Outline type that was defined */ /* in FreeType 1.x. */ /* */ /* <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 */ /* Bezier control point, while it is `on' when */ /* unset. */ /* */ /* Bit 1 is meaningful for `off' points only. If */ /* set, it indicates a third-order Bezier arc */ /* control point; and a second-order control point */ /* if unset. */ /* */ /* 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_Flags.. */ /* */ 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; /*************************************************************************/ /* */ /* <Enum> */ /* FT_Outline_Flags */ /* */ /* <Description> */ /* A simple type used to enumerates the flags in an outline's */ /* "outline_flags" field. */ /* */ /* <Fields> */ /* ft_outline_owner :: */ /* when set, this flag indicates that the outline's field arrays */ /* (i.e. "points", "flags" & "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. When set to 1, the outline will be filled using the */ /* even-odd fill rule.. (XXX: unimplemented) */ /* */ /* 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 when the outline uses the opposite direction, */ /* (typically for Type 1 fonts). This flag is ignored by the */ /* scan-converter. However, it is very important for the */ /* auto-hinter.. */ /* */ /* 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. When set, this flag hints the scan-line */ /* converter to ignore such cases. */ /* */ /* 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. */ /* */ typedef enum FT_Outline_Flags_ { ft_outline_none = 0, ft_outline_owner = 1, ft_outline_even_odd_fill = 2, ft_outline_reverse_fill = 4, ft_outline_ignore_dropouts = 8, ft_outline_high_precision = 256, ft_outline_single_pass = 512 } FT_Outline_Flags; #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_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) /*************************************************************************/ /* */ /* <FuncType> */ /* FT_Outline_MoveTo_Func */ /* */ /* <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_MoveTo_Func)( FT_Vector* to, void* user ); /*************************************************************************/ /* */ /* <FuncType> */ /* FT_Outline_LineTo_Func */ /* */ /* <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_LineTo_Func)( FT_Vector* to, void* user ); /*************************************************************************/ /* */ /* <FuncType> */ /* FT_Outline_ConicTo_Func */ /* */ /* <Description> */ /* A function pointer type use to describe the signature of a `conic */ /* to' function during outline walking/decomposition. */ /* */ /* A `conic to' is emitted to indicate a second-order Bezier 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_ConicTo_Func)( FT_Vector* control, FT_Vector* to, void* user ); /*************************************************************************/ /* */ /* <FuncType> */ /* FT_Outline_CubicTo_Func */ /* */ /* <Description> */ /* A function pointer type used to describe the signature of a `cubic */ /* to' function during outline walking/decomposition. */ /* */ /* A `cubic to' is emitted to indicate a third-order Bezier arc. */ /* */ /* <Input> */ /* control1 :: A pointer to the first Bezier control point. */ /* control2 :: A pointer to the second Bezier 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_CubicTo_Func)( FT_Vector* control1, FT_Vector* control2, FT_Vector* to, void* user ); /*************************************************************************/ /* */ /* <Struct> */ /* FT_Outline_Funcs */ /* */ /* <Description> */ /* A structure to hold various function pointers used during outline */ /* decomposition in order to emit segments, conic, and cubic Beziers, */ /* as well as `move to' and `close to' operations. */ /* */ /* <Fields> */ /* move_to :: The `move to' emitter. */ /* line_to :: The segment emitter. */ /* conic_to :: The second-order Bezier arc emitter. */ /* cubic_to :: The third-order Bezier arc emitter. */ /* */ typedef struct FT_Outline_Funcs_ { FT_Outline_MoveTo_Func move_to; FT_Outline_LineTo_Func line_to; FT_Outline_ConicTo_Func conic_to; FT_Outline_CubicTo_Func cubic_to; int shift; FT_Pos delta; } FT_Outline_Funcs; /*************************************************************************/ /* */ /* <Macro> */ /* FT_IMAGE_TAG */ /* */ /* <Description> */ /* This macro converts four letter tags which are used to label */ /* TrueType tables into an unsigned long to be used within FreeType. */ /* */ #define FT_IMAGE_TAG( _x1, _x2, _x3, _x4 ) \ (((unsigned long)_x1 << 24) | \ ((unsigned long)_x2 << 16) | \ ((unsigned long)_x3 << 8) | \ (unsigned long)_x4) /*********************************************************************** * * <Enum> * FT_Glyph_Format * * <Description> * An enumeration type used to describethe 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. * * <Fields> * ft_glyph_format_composite :: the glyph image is a composite of several * other images. This glyph format is _only_ * used with the FT_LOAD_FLAG_NO_RECURSE flag * (XXX: Which is currently iunimplemented) * * ft_glyph_format_bitmap :: the glyph image is a bitmap, and can * be described as a FT_Bitmap * * ft_glyph_format_outline :: the glyph image is a vectorial image * made of bezier control points, and can * be described as a FT_Outline * * ft_glyph_format_plotter :: the glyph image is a vectorial image * made of plotter lines (some T1 fonts like * Hershey contain glyph in this format). * ***********************************************************************/ typedef enum FT_Glyph_Format_ { ft_glyph_format_none = 0, ft_glyph_format_composite = FT_IMAGE_TAG('c','o','m','p'), ft_glyph_format_bitmap = FT_IMAGE_TAG('b','i','t','s'), ft_glyph_format_outline = FT_IMAGE_TAG('o','u','t','l'), ft_glyph_format_plotter = FT_IMAGE_TAG('p','l','o','t') } FT_Glyph_Format; /*************************************************************************/ /*************************************************************************/ /*************************************************************************/ /***** *****/ /***** R A S T E R D E F I N I T I O N S *****/ /***** *****/ /*************************************************************************/ /*************************************************************************/ /*************************************************************************/ /************************************************************************** * * * * * * * * **************************************************************************/ /*************************************************************************/ /* */ /* <Type> */ /* FT_Raster */ /* */ /* <Description> */ /* A 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 (or black) pixels */ /* when rendering a monocrhome or 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). Only used for anti-aliased */ /* rendering.. */ /* */ /* <Note> */ /* This structure is used by the span drawing callback type */ /* named FT_Raster_Span_Func, which takes the y coordinate of the */ /* span as a paremeter.. */ /* */ /* The coverage value is always between 0 and 255, even if the */ /* number of gray levels have been set through FT_Set_Gray_Levels() */ /* */ typedef struct FT_Span_ { short x; unsigned short len; unsigned char coverage; } FT_Span; /*************************************************************************/ /* */ /* <FuncType> */ /* FT_Raster_Span_Func */ /* */ /* <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 will be 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_Raster_Span_Func)( int y, int count, FT_Span* spans, void* user ); /*************************************************************************/ /* */ /* <FuncType> */ /* FT_Raster_BitTest_Func */ /* */ /* <Description> */ /* A function used as a call-back by the monochrome scan-converter */ /* to test wether a given target pixel is already set to the drawing */ /* "color". These tests are crucial to implement drop-out control */ /* per-se the TrueType spec.. */ /* */ /* <Input> */ /* y :: the pixel's y coordinate */ /* x :: the pixel's x coordinate */ /* user :: user-supplied data that is passed to the callback */ /* */ /* <Return> */ /* 1 if the pixel is "set", 0 otherwise */ /* */ typedef int (*FT_Raster_BitTest_Func)( int y, int x, void* user ); /*************************************************************************/ /* */ /* <FuncType> */ /* FT_Raster_BitSet_Func */ /* */ /* <Description> */ /* A function used as a call-back by the monochrome scan-converter */ /* used to set an individual target pixel. This is crucial to */ /* implement drop-out control per-se the TrueType spec.. */ /* */ /* <Input> */ /* y :: the pixel's y coordinate */ /* x :: the pixel's x coordinate */ /* user :: user-supplied data that is passed to the callback */ /* */ /* <Return> */ /* 1 if the pixel is "set", 0 otherwise */ /* */ typedef void (*FT_Raster_BitSet_Func)( int y, int x, void* user ); /************************************************************************** * * <Enum> * FT_Raster_Flag * * <Description> * An enumeration used to list the bit flags used in the "flags" * field of a FT_Raster_Params function. * * <Fields> * ft_raster_flag_default :: this value is 0 * * ft_raster_flag_aa :: resquests the rendering of an anti-aliased * glyph bitmap. If unset, a monchrome bitmap * will be rendered. * * ft_raster_flag_direct :: requests direct rendering over the target * bitmap. Direct rendering uses user-provided * callbacks in order to perform direct * drawing or composition over an existing * bitmap. If this bit is unset, the content * of the target bitmap **must be zeroed** ! * **************************************************************************/ typedef enum { ft_raster_flag_default = 0, ft_raster_flag_aa = 1, ft_raster_flag_direct = 2 } FT_Raster_Flag; /************************************************************************** * * <Struct> * FT_Raster_Params * * <Description> * A structure used to hold the arguments used by a raster's render * function. * * <Fields> * target :: the target bitmap * source :: pointer to the source glyph image (e.g. a FT_Outline) * flags :: rendering flags * gray_spans :: gray span drawing callback * black_spans :: black span drawing callback * bit_test :: bit test callback * bit_set :: bit set callback * user :: user-supplied data that is passed to each drawing * callback.. * * <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 will * be generated. * * When the ft_raster_flag_direct bit flag is set in "flags", the raster * will call the "gray_spans" callback to drawn gray pixel spans, in the * case of an aa glyph bitmap, or "black_spans", "bit_test" and "bit_set" * in the case of a monochrome bitmap. * * This allows direct composition over a pre-existing bitmap through * user-provided callbacks to perform the span drawing/composition. * * Note that the "bit_test" and "bit_set" callbacks are required when * rendering a monochrome bitmap, as they are crucial to implement correct * drop-out control per-se the TrueType specification.. * **************************************************************************/ typedef struct FT_Raster_Params_ { FT_Bitmap* target; void* source; int flags; FT_Raster_Span_Func gray_spans; FT_Raster_Span_Func black_spans; FT_Raster_BitTest_Func bit_test; FT_Raster_BitSet_Func bit_set; void* user; } FT_Raster_Params; /************************************************************************** * <FuncType> * FT_Raster_New_Func * * <Description> * A function used to create a new raster object. * * <Input> * memory :: handle to memory allocator. * * <Output> * raster :: handle to 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 a FT_Memory, 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_New_Func)( void* memory, FT_Raster *raster ); /************************************************************************** * <FuncType> * FT_Raster_Done_Func * * <Description> * A function used to destroy a given raster object. * * <Input> * raster :: handle to new raster object * **************************************************************************/ typedef void (*FT_Raster_Done_Func)( FT_Raster raster ); /************************************************************************** * * <FuncType> * FT_Raster_Reset_Func * * <Description> * FreeType provides an area of memory called the "render pool", * available to all registered rasters. This pool can be freely * used during a given scan-conversion but is shared by all rasters. * Its content is thus transient. * * This function is called each time the render pool changes, or * just after a new raster object is created. * * <Input> * raster :: handle to new raster object * pool_base :: address in memory of render pool * pool_size :: size in bytes of render pool * * <Note> * Rasters can ignore the render pool and rely on dynamic memory * allocation if they want to (a handle to the memory allocator is * passed to the raster constructor). However, this is not recommended * for efficiency purposes.. * **************************************************************************/ typedef void (*FT_Raster_Reset_Func)( FT_Raster raster, const char* pool_base, long pool_size ); /************************************************************************** * * <FuncType> * FT_Raster_Set_Mode_Func * * <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 :: handle to new raster object * mode :: an C string naming the mode or property to change * args :: a pointer to the new mode/property to use * **************************************************************************/ typedef int (*FT_Raster_Set_Mode_Func)( FT_Raster raster, const char* mode, void* args ); /************************************************************************** * * <FuncType> * FT_Raster_Render_Func * * <Description> * Invokes a given raster to scan-convert a given glyph image into * a target bitmap. * * <Input> * raster :: handle to raster object * params :: pointer to a 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 when 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 which support direct composition). * **************************************************************************/ typedef int (*FT_Raster_Render_Func)( FT_Raster raster, FT_Raster_Params* params ); /************************************************************************** * * <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 :: renders a glyph into a given bitmap * raster_done :: the raster destructor * **************************************************************************/ typedef struct FT_Raster_Funcs_ { FT_Glyph_Format glyph_format; FT_Raster_New_Func raster_new; FT_Raster_Reset_Func raster_reset; FT_Raster_Set_Mode_Func raster_set_mode; FT_Raster_Render_Func raster_render; FT_Raster_Done_Func raster_done; } FT_Raster_Funcs; #endif /* FTIMAGE_H */