mirror of
https://github.com/RetroDECK/ES-DE.git
synced 2024-11-22 14:15:38 +00:00
421 lines
26 KiB
C
421 lines
26 KiB
C
/***************************************************************************/
|
|
/* */
|
|
/* ftimage.h */
|
|
/* */
|
|
/* FreeType glyph image formats and default raster interface */
|
|
/* (specification). */
|
|
/* */
|
|
/* Copyright 1996-2010, 2013 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 PLUTOVG_FT_RASTER_H
|
|
#define PLUTOVG_FT_RASTER_H
|
|
|
|
#include "plutovg-ft-types.h"
|
|
|
|
/*************************************************************************/
|
|
/* */
|
|
/* <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 PVG_FT_BBox_
|
|
{
|
|
PVG_FT_Pos xMin, yMin;
|
|
PVG_FT_Pos xMax, yMax;
|
|
|
|
} PVG_FT_BBox;
|
|
|
|
/*************************************************************************/
|
|
/* */
|
|
/* <Struct> */
|
|
/* PVG_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' @PVG_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 @PVG_FT_OUTLINE_FLAGS.*/
|
|
/* */
|
|
typedef struct PVG_FT_Outline_
|
|
{
|
|
int n_contours; /* number of contours in glyph */
|
|
int n_points; /* number of points in the glyph */
|
|
|
|
PVG_FT_Vector* points; /* the outline's points */
|
|
char* tags; /* the points flags */
|
|
int* contours; /* the contour end points */
|
|
char* contours_flag; /* the contour open flags */
|
|
|
|
int flags; /* outline masks */
|
|
|
|
} PVG_FT_Outline;
|
|
|
|
|
|
/*************************************************************************/
|
|
/* */
|
|
/* <Enum> */
|
|
/* PVG_FT_OUTLINE_FLAGS */
|
|
/* */
|
|
/* <Description> */
|
|
/* A list of bit-field constants use for the flags in an outline's */
|
|
/* `flags' field. */
|
|
/* */
|
|
/* <Values> */
|
|
/* PVG_FT_OUTLINE_NONE :: */
|
|
/* Value~0 is reserved. */
|
|
/* */
|
|
/* PVG_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. */
|
|
/* */
|
|
/* PVG_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). */
|
|
/* */
|
|
/* PVG_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. */
|
|
/* */
|
|
/* */
|
|
/* */
|
|
/* There exists a second mechanism to pass the drop-out mode to the */
|
|
/* B/W rasterizer; see the `tags' field in @PVG_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 PVG_FT_OUTLINE_NONE 0x0
|
|
#define PVG_FT_OUTLINE_OWNER 0x1
|
|
#define PVG_FT_OUTLINE_EVEN_ODD_FILL 0x2
|
|
#define PVG_FT_OUTLINE_REVERSE_FILL 0x4
|
|
|
|
/* */
|
|
|
|
#define PVG_FT_CURVE_TAG( flag ) ( flag & 3 )
|
|
|
|
#define PVG_FT_CURVE_TAG_ON 1
|
|
#define PVG_FT_CURVE_TAG_CONIC 0
|
|
#define PVG_FT_CURVE_TAG_CUBIC 2
|
|
|
|
|
|
#define PVG_FT_Curve_Tag_On PVG_FT_CURVE_TAG_ON
|
|
#define PVG_FT_Curve_Tag_Conic PVG_FT_CURVE_TAG_CONIC
|
|
#define PVG_FT_Curve_Tag_Cubic PVG_FT_CURVE_TAG_CUBIC
|
|
|
|
/*************************************************************************/
|
|
/* */
|
|
/* <Function> */
|
|
/* PVG_FT_Outline_Check */
|
|
/* */
|
|
/* <Description> */
|
|
/* Check the contents of an outline descriptor. */
|
|
/* */
|
|
/* <Input> */
|
|
/* outline :: A handle to a source outline. */
|
|
/* */
|
|
/* <Return> */
|
|
/* FreeType error code. 0~means success. */
|
|
/* */
|
|
PVG_FT_Error
|
|
PVG_FT_Outline_Check( PVG_FT_Outline* outline );
|
|
|
|
|
|
/*************************************************************************/
|
|
/* */
|
|
/* <Function> */
|
|
/* PVG_FT_Outline_Get_CBox */
|
|
/* */
|
|
/* <Description> */
|
|
/* Return an outline's `control box'. The control box encloses all */
|
|
/* the outline's points, including Bézier control points. Though it */
|
|
/* coincides with the exact bounding box for most glyphs, it can be */
|
|
/* slightly larger in some situations (like when rotating an outline */
|
|
/* that contains Bézier outside arcs). */
|
|
/* */
|
|
/* Computing the control box is very fast, while getting the bounding */
|
|
/* box can take much more time as it needs to walk over all segments */
|
|
/* and arcs in the outline. To get the latter, you can use the */
|
|
/* `ftbbox' component, which is dedicated to this single task. */
|
|
/* */
|
|
/* <Input> */
|
|
/* outline :: A pointer to the source outline descriptor. */
|
|
/* */
|
|
/* <Output> */
|
|
/* acbox :: The outline's control box. */
|
|
/* */
|
|
/* <Note> */
|
|
/* See @PVG_FT_Glyph_Get_CBox for a discussion of tricky fonts. */
|
|
/* */
|
|
void
|
|
PVG_FT_Outline_Get_CBox( const PVG_FT_Outline* outline,
|
|
PVG_FT_BBox *acbox );
|
|
|
|
/*************************************************************************/
|
|
/* */
|
|
/* <Struct> */
|
|
/* PVG_FT_Span */
|
|
/* */
|
|
/* <Description> */
|
|
/* A structure used to model a single span of gray (or black) pixels */
|
|
/* when rendering a monochrome 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 */
|
|
/* @PVG_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 PVG_FT_Span_
|
|
{
|
|
int x;
|
|
int len;
|
|
int y;
|
|
unsigned char coverage;
|
|
|
|
} PVG_FT_Span;
|
|
|
|
|
|
/*************************************************************************/
|
|
/* */
|
|
/* <FuncType> */
|
|
/* PVG_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 `PVG_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
|
|
(*PVG_FT_SpanFunc)( int count,
|
|
const PVG_FT_Span* spans,
|
|
void* user );
|
|
|
|
#define PVG_FT_Raster_Span_Func PVG_FT_SpanFunc
|
|
|
|
|
|
|
|
/*************************************************************************/
|
|
/* */
|
|
/* <Enum> */
|
|
/* PVG_FT_RASTER_FLAG_XXX */
|
|
/* */
|
|
/* <Description> */
|
|
/* A list of bit flag constants as used in the `flags' field of a */
|
|
/* @PVG_FT_Raster_Params structure. */
|
|
/* */
|
|
/* <Values> */
|
|
/* PVG_FT_RASTER_FLAG_DEFAULT :: This value is 0. */
|
|
/* */
|
|
/* PVG_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). */
|
|
/* */
|
|
/* PVG_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. */
|
|
/* */
|
|
/* Note that for now, direct rendering is */
|
|
/* only possible with anti-aliased glyphs. */
|
|
/* */
|
|
/* PVG_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 */
|
|
/* @PVG_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 PVG_FT_RASTER_FLAG_DEFAULT 0x0
|
|
#define PVG_FT_RASTER_FLAG_AA 0x1
|
|
#define PVG_FT_RASTER_FLAG_DIRECT 0x2
|
|
#define PVG_FT_RASTER_FLAG_CLIP 0x4
|
|
|
|
|
|
/*************************************************************************/
|
|
/* */
|
|
/* <Struct> */
|
|
/* PVG_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 */
|
|
/* @PVG_FT_Outline). */
|
|
/* */
|
|
/* flags :: The rendering flags. */
|
|
/* */
|
|
/* gray_spans :: The gray span drawing callback. */
|
|
/* */
|
|
/* black_spans :: The black span drawing callback. UNIMPLEMENTED! */
|
|
/* */
|
|
/* bit_test :: The bit test callback. UNIMPLEMENTED! */
|
|
/* */
|
|
/* bit_set :: The bit set callback. UNIMPLEMENTED! */
|
|
/* */
|
|
/* 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 @PVG_FT_RASTER_FLAG_AA */
|
|
/* bit flag is set in the `flags' field, otherwise a monochrome */
|
|
/* bitmap is generated. */
|
|
/* */
|
|
/* If the @PVG_FT_RASTER_FLAG_DIRECT bit flag is set in `flags', the */
|
|
/* raster will call the `gray_spans' callback to draw gray pixel */
|
|
/* spans, in the case of an aa glyph bitmap, it will call */
|
|
/* `black_spans', and `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 as defined in the TrueType specification. */
|
|
/* */
|
|
typedef struct PVG_FT_Raster_Params_
|
|
{
|
|
const void* source;
|
|
int flags;
|
|
PVG_FT_SpanFunc gray_spans;
|
|
void* user;
|
|
PVG_FT_BBox clip_box;
|
|
|
|
} PVG_FT_Raster_Params;
|
|
|
|
|
|
void
|
|
PVG_FT_Raster_Render(const PVG_FT_Raster_Params *params);
|
|
|
|
#endif // PLUTOVG_FT_RASTER_H
|