--- a/misc/libfreetype/src/smooth/ftgrays.c Tue Jul 16 11:14:27 2013 +0200
+++ /dev/null Thu Jan 01 00:00:00 1970 +0000
@@ -1,2055 +0,0 @@
-/***************************************************************************/
-/* */
-/* ftgrays.c */
-/* */
-/* A new `perfect' anti-aliasing renderer (body). */
-/* */
-/* Copyright 2000-2003, 2005-2011 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. */
-/* */
-/***************************************************************************/
-
- /*************************************************************************/
- /* */
- /* This file can be compiled without the rest of the FreeType engine, by */
- /* defining the _STANDALONE_ macro when compiling it. You also need to */
- /* put the files `ftgrays.h' and `ftimage.h' into the current */
- /* compilation directory. Typically, you could do something like */
- /* */
- /* - copy `src/smooth/ftgrays.c' (this file) to your current directory */
- /* */
- /* - copy `include/freetype/ftimage.h' and `src/smooth/ftgrays.h' to the */
- /* same directory */
- /* */
- /* - compile `ftgrays' with the _STANDALONE_ macro defined, as in */
- /* */
- /* cc -c -D_STANDALONE_ ftgrays.c */
- /* */
- /* The renderer can be initialized with a call to */
- /* `ft_gray_raster.raster_new'; an anti-aliased bitmap can be generated */
- /* with a call to `ft_gray_raster.raster_render'. */
- /* */
- /* See the comments and documentation in the file `ftimage.h' for more */
- /* details on how the raster works. */
- /* */
- /*************************************************************************/
-
- /*************************************************************************/
- /* */
- /* This is a new anti-aliasing scan-converter for FreeType 2. The */
- /* algorithm used here is _very_ different from the one in the standard */
- /* `ftraster' module. Actually, `ftgrays' computes the _exact_ */
- /* coverage of the outline on each pixel cell. */
- /* */
- /* It is based on ideas that I initially found in Raph Levien's */
- /* excellent LibArt graphics library (see http://www.levien.com/libart */
- /* for more information, though the web pages do not tell anything */
- /* about the renderer; you'll have to dive into the source code to */
- /* understand how it works). */
- /* */
- /* Note, however, that this is a _very_ different implementation */
- /* compared to Raph's. Coverage information is stored in a very */
- /* different way, and I don't use sorted vector paths. Also, it doesn't */
- /* use floating point values. */
- /* */
- /* This renderer has the following advantages: */
- /* */
- /* - It doesn't need an intermediate bitmap. Instead, one can supply a */
- /* callback function that will be called by the renderer to draw gray */
- /* spans on any target surface. You can thus do direct composition on */
- /* any kind of bitmap, provided that you give the renderer the right */
- /* callback. */
- /* */
- /* - A perfect anti-aliaser, i.e., it computes the _exact_ coverage on */
- /* each pixel cell. */
- /* */
- /* - It performs a single pass on the outline (the `standard' FT2 */
- /* renderer makes two passes). */
- /* */
- /* - It can easily be modified to render to _any_ number of gray levels */
- /* cheaply. */
- /* */
- /* - For small (< 20) pixel sizes, it is faster than the standard */
- /* renderer. */
- /* */
- /*************************************************************************/
-
-
- /*************************************************************************/
- /* */
- /* The macro FT_COMPONENT is used in trace mode. It is an implicit */
- /* parameter of the FT_TRACE() and FT_ERROR() macros, used to print/log */
- /* messages during execution. */
- /* */
-#undef FT_COMPONENT
-#define FT_COMPONENT trace_smooth
-
-
-#ifdef _STANDALONE_
-
-
- /* define this to dump debugging information */
-/* #define FT_DEBUG_LEVEL_TRACE */
-
-
-#ifdef FT_DEBUG_LEVEL_TRACE
-#include <stdio.h>
-#include <stdarg.h>
-#endif
-
-#include <stddef.h>
-#include <string.h>
-#include <setjmp.h>
-#include <limits.h>
-#define FT_UINT_MAX UINT_MAX
-#define FT_INT_MAX INT_MAX
-
-#define ft_memset memset
-
-#define ft_setjmp setjmp
-#define ft_longjmp longjmp
-#define ft_jmp_buf jmp_buf
-
-typedef ptrdiff_t FT_PtrDist;
-
-
-#define ErrRaster_Invalid_Mode -2
-#define ErrRaster_Invalid_Outline -1
-#define ErrRaster_Invalid_Argument -3
-#define ErrRaster_Memory_Overflow -4
-
-#define FT_BEGIN_HEADER
-#define FT_END_HEADER
-
-#include "ftimage.h"
-#include "ftgrays.h"
-
-
- /* This macro is used to indicate that a function parameter is unused. */
- /* Its purpose is simply to reduce compiler warnings. Note also that */
- /* simply defining it as `(void)x' doesn't avoid warnings with certain */
- /* ANSI compilers (e.g. LCC). */
-#define FT_UNUSED( x ) (x) = (x)
-
-
- /* we only use level 5 & 7 tracing messages; cf. ftdebug.h */
-
-#ifdef FT_DEBUG_LEVEL_TRACE
-
- void
- FT_Message( const char* fmt,
- ... )
- {
- va_list ap;
-
-
- va_start( ap, fmt );
- vfprintf( stderr, fmt, ap );
- va_end( ap );
- }
-
- /* we don't handle tracing levels in stand-alone mode; */
-#ifndef FT_TRACE5
-#define FT_TRACE5( varformat ) FT_Message varformat
-#endif
-#ifndef FT_TRACE7
-#define FT_TRACE7( varformat ) FT_Message varformat
-#endif
-#ifndef FT_ERROR
-#define FT_ERROR( varformat ) FT_Message varformat
-#endif
-
-#else /* !FT_DEBUG_LEVEL_TRACE */
-
-#define FT_TRACE5( x ) do { } while ( 0 ) /* nothing */
-#define FT_TRACE7( x ) do { } while ( 0 ) /* nothing */
-#define FT_ERROR( x ) do { } while ( 0 ) /* nothing */
-
-#endif /* !FT_DEBUG_LEVEL_TRACE */
-
-
-#define FT_DEFINE_OUTLINE_FUNCS( class_, \
- move_to_, line_to_, \
- conic_to_, cubic_to_, \
- shift_, delta_ ) \
- static const FT_Outline_Funcs class_ = \
- { \
- move_to_, \
- line_to_, \
- conic_to_, \
- cubic_to_, \
- shift_, \
- delta_ \
- };
-
-#define FT_DEFINE_RASTER_FUNCS( class_, glyph_format_, \
- raster_new_, raster_reset_, \
- raster_set_mode_, raster_render_, \
- raster_done_ ) \
- const FT_Raster_Funcs class_ = \
- { \
- glyph_format_, \
- raster_new_, \
- raster_reset_, \
- raster_set_mode_, \
- raster_render_, \
- raster_done_ \
- };
-
-#else /* !_STANDALONE_ */
-
-
-#include <ft2build.h>
-#include "ftgrays.h"
-#include FT_INTERNAL_OBJECTS_H
-#include FT_INTERNAL_DEBUG_H
-#include FT_OUTLINE_H
-
-#include "ftsmerrs.h"
-
-#include "ftspic.h"
-
-#define ErrRaster_Invalid_Mode Smooth_Err_Cannot_Render_Glyph
-#define ErrRaster_Invalid_Outline Smooth_Err_Invalid_Outline
-#define ErrRaster_Memory_Overflow Smooth_Err_Out_Of_Memory
-#define ErrRaster_Invalid_Argument Smooth_Err_Invalid_Argument
-
-#endif /* !_STANDALONE_ */
-
-#ifndef FT_MEM_SET
-#define FT_MEM_SET( d, s, c ) ft_memset( d, s, c )
-#endif
-
-#ifndef FT_MEM_ZERO
-#define FT_MEM_ZERO( dest, count ) FT_MEM_SET( dest, 0, count )
-#endif
-
- /* as usual, for the speed hungry :-) */
-
-#ifndef FT_STATIC_RASTER
-
-#define RAS_ARG PWorker worker
-#define RAS_ARG_ PWorker worker,
-
-#define RAS_VAR worker
-#define RAS_VAR_ worker,
-
-#else /* FT_STATIC_RASTER */
-
-#define RAS_ARG /* empty */
-#define RAS_ARG_ /* empty */
-#define RAS_VAR /* empty */
-#define RAS_VAR_ /* empty */
-
-#endif /* FT_STATIC_RASTER */
-
-
- /* must be at least 6 bits! */
-#define PIXEL_BITS 8
-
-#define ONE_PIXEL ( 1L << PIXEL_BITS )
-#define PIXEL_MASK ( -1L << PIXEL_BITS )
-#define TRUNC( x ) ( (TCoord)( (x) >> PIXEL_BITS ) )
-#define SUBPIXELS( x ) ( (TPos)(x) << PIXEL_BITS )
-#define FLOOR( x ) ( (x) & -ONE_PIXEL )
-#define CEILING( x ) ( ( (x) + ONE_PIXEL - 1 ) & -ONE_PIXEL )
-#define ROUND( x ) ( ( (x) + ONE_PIXEL / 2 ) & -ONE_PIXEL )
-
-#if PIXEL_BITS >= 6
-#define UPSCALE( x ) ( (x) << ( PIXEL_BITS - 6 ) )
-#define DOWNSCALE( x ) ( (x) >> ( PIXEL_BITS - 6 ) )
-#else
-#define UPSCALE( x ) ( (x) >> ( 6 - PIXEL_BITS ) )
-#define DOWNSCALE( x ) ( (x) << ( 6 - PIXEL_BITS ) )
-#endif
-
-
- /*************************************************************************/
- /* */
- /* TYPE DEFINITIONS */
- /* */
-
- /* don't change the following types to FT_Int or FT_Pos, since we might */
- /* need to define them to "float" or "double" when experimenting with */
- /* new algorithms */
-
- typedef long TCoord; /* integer scanline/pixel coordinate */
- typedef long TPos; /* sub-pixel coordinate */
-
- /* determine the type used to store cell areas. This normally takes at */
- /* least PIXEL_BITS*2 + 1 bits. On 16-bit systems, we need to use */
- /* `long' instead of `int', otherwise bad things happen */
-
-#if PIXEL_BITS <= 7
-
- typedef int TArea;
-
-#else /* PIXEL_BITS >= 8 */
-
- /* approximately determine the size of integers using an ANSI-C header */
-#if FT_UINT_MAX == 0xFFFFU
- typedef long TArea;
-#else
- typedef int TArea;
-#endif
-
-#endif /* PIXEL_BITS >= 8 */
-
-
- /* maximal number of gray spans in a call to the span callback */
-#define FT_MAX_GRAY_SPANS 32
-
-
- typedef struct TCell_* PCell;
-
- typedef struct TCell_
- {
- TPos x; /* same with TWorker.ex */
- TCoord cover; /* same with TWorker.cover */
- TArea area;
- PCell next;
-
- } TCell;
-
-
- typedef struct TWorker_
- {
- TCoord ex, ey;
- TPos min_ex, max_ex;
- TPos min_ey, max_ey;
- TPos count_ex, count_ey;
-
- TArea area;
- TCoord cover;
- int invalid;
-
- PCell cells;
- FT_PtrDist max_cells;
- FT_PtrDist num_cells;
-
- TCoord cx, cy;
- TPos x, y;
-
- TPos last_ey;
-
- FT_Vector bez_stack[32 * 3 + 1];
- int lev_stack[32];
-
- FT_Outline outline;
- FT_Bitmap target;
- FT_BBox clip_box;
-
- FT_Span gray_spans[FT_MAX_GRAY_SPANS];
- int num_gray_spans;
-
- FT_Raster_Span_Func render_span;
- void* render_span_data;
- int span_y;
-
- int band_size;
- int band_shoot;
-
- ft_jmp_buf jump_buffer;
-
- void* buffer;
- long buffer_size;
-
- PCell* ycells;
- TPos ycount;
-
- } TWorker, *PWorker;
-
-
-#ifndef FT_STATIC_RASTER
-#define ras (*worker)
-#else
- static TWorker ras;
-#endif
-
-
- typedef struct TRaster_
- {
- void* buffer;
- long buffer_size;
- int band_size;
- void* memory;
- PWorker worker;
-
- } TRaster, *PRaster;
-
-
-
- /*************************************************************************/
- /* */
- /* Initialize the cells table. */
- /* */
- static void
- gray_init_cells( RAS_ARG_ void* buffer,
- long byte_size )
- {
- ras.buffer = buffer;
- ras.buffer_size = byte_size;
-
- ras.ycells = (PCell*) buffer;
- ras.cells = NULL;
- ras.max_cells = 0;
- ras.num_cells = 0;
- ras.area = 0;
- ras.cover = 0;
- ras.invalid = 1;
- }
-
-
- /*************************************************************************/
- /* */
- /* Compute the outline bounding box. */
- /* */
- static void
- gray_compute_cbox( RAS_ARG )
- {
- FT_Outline* outline = &ras.outline;
- FT_Vector* vec = outline->points;
- FT_Vector* limit = vec + outline->n_points;
-
-
- if ( outline->n_points <= 0 )
- {
- ras.min_ex = ras.max_ex = 0;
- ras.min_ey = ras.max_ey = 0;
- return;
- }
-
- ras.min_ex = ras.max_ex = vec->x;
- ras.min_ey = ras.max_ey = vec->y;
-
- vec++;
-
- for ( ; vec < limit; vec++ )
- {
- TPos x = vec->x;
- TPos y = vec->y;
-
-
- if ( x < ras.min_ex ) ras.min_ex = x;
- if ( x > ras.max_ex ) ras.max_ex = x;
- if ( y < ras.min_ey ) ras.min_ey = y;
- if ( y > ras.max_ey ) ras.max_ey = y;
- }
-
- /* truncate the bounding box to integer pixels */
- ras.min_ex = ras.min_ex >> 6;
- ras.min_ey = ras.min_ey >> 6;
- ras.max_ex = ( ras.max_ex + 63 ) >> 6;
- ras.max_ey = ( ras.max_ey + 63 ) >> 6;
- }
-
-
- /*************************************************************************/
- /* */
- /* Record the current cell in the table. */
- /* */
- static PCell
- gray_find_cell( RAS_ARG )
- {
- PCell *pcell, cell;
- TPos x = ras.ex;
-
-
- if ( x > ras.count_ex )
- x = ras.count_ex;
-
- pcell = &ras.ycells[ras.ey];
- for (;;)
- {
- cell = *pcell;
- if ( cell == NULL || cell->x > x )
- break;
-
- if ( cell->x == x )
- goto Exit;
-
- pcell = &cell->next;
- }
-
- if ( ras.num_cells >= ras.max_cells )
- ft_longjmp( ras.jump_buffer, 1 );
-
- cell = ras.cells + ras.num_cells++;
- cell->x = x;
- cell->area = 0;
- cell->cover = 0;
-
- cell->next = *pcell;
- *pcell = cell;
-
- Exit:
- return cell;
- }
-
-
- static void
- gray_record_cell( RAS_ARG )
- {
- if ( !ras.invalid && ( ras.area | ras.cover ) )
- {
- PCell cell = gray_find_cell( RAS_VAR );
-
-
- cell->area += ras.area;
- cell->cover += ras.cover;
- }
- }
-
-
- /*************************************************************************/
- /* */
- /* Set the current cell to a new position. */
- /* */
- static void
- gray_set_cell( RAS_ARG_ TCoord ex,
- TCoord ey )
- {
- /* Move the cell pointer to a new position. We set the `invalid' */
- /* flag to indicate that the cell isn't part of those we're interested */
- /* in during the render phase. This means that: */
- /* */
- /* . the new vertical position must be within min_ey..max_ey-1. */
- /* . the new horizontal position must be strictly less than max_ex */
- /* */
- /* Note that if a cell is to the left of the clipping region, it is */
- /* actually set to the (min_ex-1) horizontal position. */
-
- /* All cells that are on the left of the clipping region go to the */
- /* min_ex - 1 horizontal position. */
- ey -= ras.min_ey;
-
- if ( ex > ras.max_ex )
- ex = ras.max_ex;
-
- ex -= ras.min_ex;
- if ( ex < 0 )
- ex = -1;
-
- /* are we moving to a different cell ? */
- if ( ex != ras.ex || ey != ras.ey )
- {
- /* record the current one if it is valid */
- if ( !ras.invalid )
- gray_record_cell( RAS_VAR );
-
- ras.area = 0;
- ras.cover = 0;
- }
-
- ras.ex = ex;
- ras.ey = ey;
- ras.invalid = ( (unsigned)ey >= (unsigned)ras.count_ey ||
- ex >= ras.count_ex );
- }
-
-
- /*************************************************************************/
- /* */
- /* Start a new contour at a given cell. */
- /* */
- static void
- gray_start_cell( RAS_ARG_ TCoord ex,
- TCoord ey )
- {
- if ( ex > ras.max_ex )
- ex = (TCoord)( ras.max_ex );
-
- if ( ex < ras.min_ex )
- ex = (TCoord)( ras.min_ex - 1 );
-
- ras.area = 0;
- ras.cover = 0;
- ras.ex = ex - ras.min_ex;
- ras.ey = ey - ras.min_ey;
- ras.last_ey = SUBPIXELS( ey );
- ras.invalid = 0;
-
- gray_set_cell( RAS_VAR_ ex, ey );
- }
-
-
- /*************************************************************************/
- /* */
- /* Render a scanline as one or more cells. */
- /* */
- static void
- gray_render_scanline( RAS_ARG_ TCoord ey,
- TPos x1,
- TCoord y1,
- TPos x2,
- TCoord y2 )
- {
- TCoord ex1, ex2, fx1, fx2, delta, mod, lift, rem;
- long p, first, dx;
- int incr;
-
-
- dx = x2 - x1;
-
- ex1 = TRUNC( x1 );
- ex2 = TRUNC( x2 );
- fx1 = (TCoord)( x1 - SUBPIXELS( ex1 ) );
- fx2 = (TCoord)( x2 - SUBPIXELS( ex2 ) );
-
- /* trivial case. Happens often */
- if ( y1 == y2 )
- {
- gray_set_cell( RAS_VAR_ ex2, ey );
- return;
- }
-
- /* everything is located in a single cell. That is easy! */
- /* */
- if ( ex1 == ex2 )
- {
- delta = y2 - y1;
- ras.area += (TArea)(( fx1 + fx2 ) * delta);
- ras.cover += delta;
- return;
- }
-
- /* ok, we'll have to render a run of adjacent cells on the same */
- /* scanline... */
- /* */
- p = ( ONE_PIXEL - fx1 ) * ( y2 - y1 );
- first = ONE_PIXEL;
- incr = 1;
-
- if ( dx < 0 )
- {
- p = fx1 * ( y2 - y1 );
- first = 0;
- incr = -1;
- dx = -dx;
- }
-
- delta = (TCoord)( p / dx );
- mod = (TCoord)( p % dx );
- if ( mod < 0 )
- {
- delta--;
- mod += (TCoord)dx;
- }
-
- ras.area += (TArea)(( fx1 + first ) * delta);
- ras.cover += delta;
-
- ex1 += incr;
- gray_set_cell( RAS_VAR_ ex1, ey );
- y1 += delta;
-
- if ( ex1 != ex2 )
- {
- p = ONE_PIXEL * ( y2 - y1 + delta );
- lift = (TCoord)( p / dx );
- rem = (TCoord)( p % dx );
- if ( rem < 0 )
- {
- lift--;
- rem += (TCoord)dx;
- }
-
- mod -= (int)dx;
-
- while ( ex1 != ex2 )
- {
- delta = lift;
- mod += rem;
- if ( mod >= 0 )
- {
- mod -= (TCoord)dx;
- delta++;
- }
-
- ras.area += (TArea)(ONE_PIXEL * delta);
- ras.cover += delta;
- y1 += delta;
- ex1 += incr;
- gray_set_cell( RAS_VAR_ ex1, ey );
- }
- }
-
- delta = y2 - y1;
- ras.area += (TArea)(( fx2 + ONE_PIXEL - first ) * delta);
- ras.cover += delta;
- }
-
-
- /*************************************************************************/
- /* */
- /* Render a given line as a series of scanlines. */
- /* */
- static void
- gray_render_line( RAS_ARG_ TPos to_x,
- TPos to_y )
- {
- TCoord ey1, ey2, fy1, fy2, mod;
- TPos dx, dy, x, x2;
- long p, first;
- int delta, rem, lift, incr;
-
-
- ey1 = TRUNC( ras.last_ey );
- ey2 = TRUNC( to_y ); /* if (ey2 >= ras.max_ey) ey2 = ras.max_ey-1; */
- fy1 = (TCoord)( ras.y - ras.last_ey );
- fy2 = (TCoord)( to_y - SUBPIXELS( ey2 ) );
-
- dx = to_x - ras.x;
- dy = to_y - ras.y;
-
- /* XXX: we should do something about the trivial case where dx == 0, */
- /* as it happens very often! */
-
- /* perform vertical clipping */
- {
- TCoord min, max;
-
-
- min = ey1;
- max = ey2;
- if ( ey1 > ey2 )
- {
- min = ey2;
- max = ey1;
- }
- if ( min >= ras.max_ey || max < ras.min_ey )
- goto End;
- }
-
- /* everything is on a single scanline */
- if ( ey1 == ey2 )
- {
- gray_render_scanline( RAS_VAR_ ey1, ras.x, fy1, to_x, fy2 );
- goto End;
- }
-
- /* vertical line - avoid calling gray_render_scanline */
- incr = 1;
-
- if ( dx == 0 )
- {
- TCoord ex = TRUNC( ras.x );
- TCoord two_fx = (TCoord)( ( ras.x - SUBPIXELS( ex ) ) << 1 );
- TArea area;
-
-
- first = ONE_PIXEL;
- if ( dy < 0 )
- {
- first = 0;
- incr = -1;
- }
-
- delta = (int)( first - fy1 );
- ras.area += (TArea)two_fx * delta;
- ras.cover += delta;
- ey1 += incr;
-
- gray_set_cell( RAS_VAR_ ex, ey1 );
-
- delta = (int)( first + first - ONE_PIXEL );
- area = (TArea)two_fx * delta;
- while ( ey1 != ey2 )
- {
- ras.area += area;
- ras.cover += delta;
- ey1 += incr;
-
- gray_set_cell( RAS_VAR_ ex, ey1 );
- }
-
- delta = (int)( fy2 - ONE_PIXEL + first );
- ras.area += (TArea)two_fx * delta;
- ras.cover += delta;
-
- goto End;
- }
-
- /* ok, we have to render several scanlines */
- p = ( ONE_PIXEL - fy1 ) * dx;
- first = ONE_PIXEL;
- incr = 1;
-
- if ( dy < 0 )
- {
- p = fy1 * dx;
- first = 0;
- incr = -1;
- dy = -dy;
- }
-
- delta = (int)( p / dy );
- mod = (int)( p % dy );
- if ( mod < 0 )
- {
- delta--;
- mod += (TCoord)dy;
- }
-
- x = ras.x + delta;
- gray_render_scanline( RAS_VAR_ ey1, ras.x, fy1, x, (TCoord)first );
-
- ey1 += incr;
- gray_set_cell( RAS_VAR_ TRUNC( x ), ey1 );
-
- if ( ey1 != ey2 )
- {
- p = ONE_PIXEL * dx;
- lift = (int)( p / dy );
- rem = (int)( p % dy );
- if ( rem < 0 )
- {
- lift--;
- rem += (int)dy;
- }
- mod -= (int)dy;
-
- while ( ey1 != ey2 )
- {
- delta = lift;
- mod += rem;
- if ( mod >= 0 )
- {
- mod -= (int)dy;
- delta++;
- }
-
- x2 = x + delta;
- gray_render_scanline( RAS_VAR_ ey1, x,
- (TCoord)( ONE_PIXEL - first ), x2,
- (TCoord)first );
- x = x2;
-
- ey1 += incr;
- gray_set_cell( RAS_VAR_ TRUNC( x ), ey1 );
- }
- }
-
- gray_render_scanline( RAS_VAR_ ey1, x,
- (TCoord)( ONE_PIXEL - first ), to_x,
- fy2 );
-
- End:
- ras.x = to_x;
- ras.y = to_y;
- ras.last_ey = SUBPIXELS( ey2 );
- }
-
-
- static void
- gray_split_conic( FT_Vector* base )
- {
- TPos a, b;
-
-
- base[4].x = base[2].x;
- b = base[1].x;
- a = base[3].x = ( base[2].x + b ) / 2;
- b = base[1].x = ( base[0].x + b ) / 2;
- base[2].x = ( a + b ) / 2;
-
- base[4].y = base[2].y;
- b = base[1].y;
- a = base[3].y = ( base[2].y + b ) / 2;
- b = base[1].y = ( base[0].y + b ) / 2;
- base[2].y = ( a + b ) / 2;
- }
-
-
- static void
- gray_render_conic( RAS_ARG_ const FT_Vector* control,
- const FT_Vector* to )
- {
- TPos dx, dy;
- int top, level;
- int* levels;
- FT_Vector* arc;
-
-
- arc = ras.bez_stack;
- arc[0].x = UPSCALE( to->x );
- arc[0].y = UPSCALE( to->y );
- arc[1].x = UPSCALE( control->x );
- arc[1].y = UPSCALE( control->y );
- arc[2].x = ras.x;
- arc[2].y = ras.y;
-
- dx = FT_ABS( arc[2].x + arc[0].x - 2 * arc[1].x );
- dy = FT_ABS( arc[2].y + arc[0].y - 2 * arc[1].y );
- if ( dx < dy )
- dx = dy;
-
- level = 0;
- while ( dx > ONE_PIXEL / 6 )
- {
- dx >>= 2;
- level++;
- }
-
- levels = ras.lev_stack;
- levels[0] = level;
- top = 0;
-
- do
- {
- level = levels[top];
- if ( level > 1 )
- {
- /* check that the arc crosses the current band */
- TPos min, max, y;
-
-
- min = max = arc[0].y;
-
- y = arc[1].y;
- if ( y < min ) min = y;
- if ( y > max ) max = y;
-
- y = arc[2].y;
- if ( y < min ) min = y;
- if ( y > max ) max = y;
-
- if ( TRUNC( min ) >= ras.max_ey || TRUNC( max ) < ras.min_ey )
- goto Draw;
-
- gray_split_conic( arc );
- arc += 2;
- top++;
- levels[top] = levels[top - 1] = level - 1;
- continue;
- }
-
- Draw:
- gray_render_line( RAS_VAR_ arc[0].x, arc[0].y );
- top--;
- arc -= 2;
-
- } while ( top >= 0 );
- }
-
-
- static void
- gray_split_cubic( FT_Vector* base )
- {
- TPos a, b, c, d;
-
-
- base[6].x = base[3].x;
- c = base[1].x;
- d = base[2].x;
- base[1].x = a = ( base[0].x + c ) / 2;
- base[5].x = b = ( base[3].x + d ) / 2;
- c = ( c + d ) / 2;
- base[2].x = a = ( a + c ) / 2;
- base[4].x = b = ( b + c ) / 2;
- base[3].x = ( a + b ) / 2;
-
- base[6].y = base[3].y;
- c = base[1].y;
- d = base[2].y;
- base[1].y = a = ( base[0].y + c ) / 2;
- base[5].y = b = ( base[3].y + d ) / 2;
- c = ( c + d ) / 2;
- base[2].y = a = ( a + c ) / 2;
- base[4].y = b = ( b + c ) / 2;
- base[3].y = ( a + b ) / 2;
- }
-
-
- static void
- gray_render_cubic( RAS_ARG_ const FT_Vector* control1,
- const FT_Vector* control2,
- const FT_Vector* to )
- {
- FT_Vector* arc;
-
-
- arc = ras.bez_stack;
- arc[0].x = UPSCALE( to->x );
- arc[0].y = UPSCALE( to->y );
- arc[1].x = UPSCALE( control2->x );
- arc[1].y = UPSCALE( control2->y );
- arc[2].x = UPSCALE( control1->x );
- arc[2].y = UPSCALE( control1->y );
- arc[3].x = ras.x;
- arc[3].y = ras.y;
-
- for (;;)
- {
- /* Check that the arc crosses the current band. */
- TPos min, max, y;
-
-
- min = max = arc[0].y;
-
- y = arc[1].y;
- if ( y < min )
- min = y;
- if ( y > max )
- max = y;
-
- y = arc[2].y;
- if ( y < min )
- min = y;
- if ( y > max )
- max = y;
-
- y = arc[3].y;
- if ( y < min )
- min = y;
- if ( y > max )
- max = y;
-
- if ( TRUNC( min ) >= ras.max_ey || TRUNC( max ) < ras.min_ey )
- goto Draw;
-
- /* Decide whether to split or draw. See `Rapid Termination */
- /* Evaluation for Recursive Subdivision of Bezier Curves' by Thomas */
- /* F. Hain, at */
- /* http://www.cis.southalabama.edu/~hain/general/Publications/Bezier/Camera-ready%20CISST02%202.pdf */
-
- {
- TPos dx, dy, dx_, dy_;
- TPos dx1, dy1, dx2, dy2;
- TPos L, s, s_limit;
-
-
- /* dx and dy are x and y components of the P0-P3 chord vector. */
- dx = arc[3].x - arc[0].x;
- dy = arc[3].y - arc[0].y;
-
- /* L is an (under)estimate of the Euclidean distance P0-P3. */
- /* */
- /* If dx >= dy, then r = sqrt(dx^2 + dy^2) can be overestimated */
- /* with least maximum error by */
- /* */
- /* r_upperbound = dx + (sqrt(2) - 1) * dy , */
- /* */
- /* where sqrt(2) - 1 can be (over)estimated by 107/256, giving an */
- /* error of no more than 8.4%. */
- /* */
- /* Similarly, some elementary calculus shows that r can be */
- /* underestimated with least maximum error by */
- /* */
- /* r_lowerbound = sqrt(2 + sqrt(2)) / 2 * dx */
- /* + sqrt(2 - sqrt(2)) / 2 * dy . */
- /* */
- /* 236/256 and 97/256 are (under)estimates of the two algebraic */
- /* numbers, giving an error of no more than 8.1%. */
-
- dx_ = FT_ABS( dx );
- dy_ = FT_ABS( dy );
-
- /* This is the same as */
- /* */
- /* L = ( 236 * FT_MAX( dx_, dy_ ) */
- /* + 97 * FT_MIN( dx_, dy_ ) ) >> 8; */
- L = ( dx_ > dy_ ? 236 * dx_ + 97 * dy_
- : 97 * dx_ + 236 * dy_ ) >> 8;
-
- /* Avoid possible arithmetic overflow below by splitting. */
- if ( L > 32767 )
- goto Split;
-
- /* Max deviation may be as much as (s/L) * 3/4 (if Hain's v = 1). */
- s_limit = L * (TPos)( ONE_PIXEL / 6 );
-
- /* s is L * the perpendicular distance from P1 to the line P0-P3. */
- dx1 = arc[1].x - arc[0].x;
- dy1 = arc[1].y - arc[0].y;
- s = FT_ABS( dy * dx1 - dx * dy1 );
-
- if ( s > s_limit )
- goto Split;
-
- /* s is L * the perpendicular distance from P2 to the line P0-P3. */
- dx2 = arc[2].x - arc[0].x;
- dy2 = arc[2].y - arc[0].y;
- s = FT_ABS( dy * dx2 - dx * dy2 );
-
- if ( s > s_limit )
- goto Split;
-
- /* If P1 or P2 is outside P0-P3, split the curve. */
- if ( dy * dy1 + dx * dx1 < 0 ||
- dy * dy2 + dx * dx2 < 0 ||
- dy * (arc[3].y - arc[1].y) + dx * (arc[3].x - arc[1].x) < 0 ||
- dy * (arc[3].y - arc[2].y) + dx * (arc[3].x - arc[2].x) < 0 )
- goto Split;
-
- /* No reason to split. */
- goto Draw;
- }
-
- Split:
- gray_split_cubic( arc );
- arc += 3;
- continue;
-
- Draw:
- gray_render_line( RAS_VAR_ arc[0].x, arc[0].y );
-
- if ( arc == ras.bez_stack )
- return;
-
- arc -= 3;
- }
- }
-
-
- static int
- gray_move_to( const FT_Vector* to,
- PWorker worker )
- {
- TPos x, y;
-
-
- /* record current cell, if any */
- gray_record_cell( RAS_VAR );
-
- /* start to a new position */
- x = UPSCALE( to->x );
- y = UPSCALE( to->y );
-
- gray_start_cell( RAS_VAR_ TRUNC( x ), TRUNC( y ) );
-
- worker->x = x;
- worker->y = y;
- return 0;
- }
-
-
- static int
- gray_line_to( const FT_Vector* to,
- PWorker worker )
- {
- gray_render_line( RAS_VAR_ UPSCALE( to->x ), UPSCALE( to->y ) );
- return 0;
- }
-
-
- static int
- gray_conic_to( const FT_Vector* control,
- const FT_Vector* to,
- PWorker worker )
- {
- gray_render_conic( RAS_VAR_ control, to );
- return 0;
- }
-
-
- static int
- gray_cubic_to( const FT_Vector* control1,
- const FT_Vector* control2,
- const FT_Vector* to,
- PWorker worker )
- {
- gray_render_cubic( RAS_VAR_ control1, control2, to );
- return 0;
- }
-
-
- static void
- gray_render_span( int y,
- int count,
- const FT_Span* spans,
- PWorker worker )
- {
- unsigned char* p;
- FT_Bitmap* map = &worker->target;
-
-
- /* first of all, compute the scanline offset */
- p = (unsigned char*)map->buffer - y * map->pitch;
- if ( map->pitch >= 0 )
- p += (unsigned)( ( map->rows - 1 ) * map->pitch );
-
- for ( ; count > 0; count--, spans++ )
- {
- unsigned char coverage = spans->coverage;
-
-
- if ( coverage )
- {
- /* For small-spans it is faster to do it by ourselves than
- * calling `memset'. This is mainly due to the cost of the
- * function call.
- */
- if ( spans->len >= 8 )
- FT_MEM_SET( p + spans->x, (unsigned char)coverage, spans->len );
- else
- {
- unsigned char* q = p + spans->x;
-
-
- switch ( spans->len )
- {
- case 7: *q++ = (unsigned char)coverage;
- case 6: *q++ = (unsigned char)coverage;
- case 5: *q++ = (unsigned char)coverage;
- case 4: *q++ = (unsigned char)coverage;
- case 3: *q++ = (unsigned char)coverage;
- case 2: *q++ = (unsigned char)coverage;
- case 1: *q = (unsigned char)coverage;
- default:
- ;
- }
- }
- }
- }
- }
-
-
- static void
- gray_hline( RAS_ARG_ TCoord x,
- TCoord y,
- TPos area,
- TCoord acount )
- {
- FT_Span* span;
- int count;
- int coverage;
-
-
- /* compute the coverage line's coverage, depending on the */
- /* outline fill rule */
- /* */
- /* the coverage percentage is area/(PIXEL_BITS*PIXEL_BITS*2) */
- /* */
- coverage = (int)( area >> ( PIXEL_BITS * 2 + 1 - 8 ) );
- /* use range 0..256 */
- if ( coverage < 0 )
- coverage = -coverage;
-
- if ( ras.outline.flags & FT_OUTLINE_EVEN_ODD_FILL )
- {
- coverage &= 511;
-
- if ( coverage > 256 )
- coverage = 512 - coverage;
- else if ( coverage == 256 )
- coverage = 255;
- }
- else
- {
- /* normal non-zero winding rule */
- if ( coverage >= 256 )
- coverage = 255;
- }
-
- y += (TCoord)ras.min_ey;
- x += (TCoord)ras.min_ex;
-
- /* FT_Span.x is a 16-bit short, so limit our coordinates appropriately */
- if ( x >= 32767 )
- x = 32767;
-
- /* FT_Span.y is an integer, so limit our coordinates appropriately */
- if ( y >= FT_INT_MAX )
- y = FT_INT_MAX;
-
- if ( coverage )
- {
- /* see whether we can add this span to the current list */
- count = ras.num_gray_spans;
- span = ras.gray_spans + count - 1;
- if ( count > 0 &&
- ras.span_y == y &&
- (int)span->x + span->len == (int)x &&
- span->coverage == coverage )
- {
- span->len = (unsigned short)( span->len + acount );
- return;
- }
-
- if ( ras.span_y != y || count >= FT_MAX_GRAY_SPANS )
- {
- if ( ras.render_span && count > 0 )
- ras.render_span( ras.span_y, count, ras.gray_spans,
- ras.render_span_data );
-
-#ifdef FT_DEBUG_LEVEL_TRACE
-
- if ( count > 0 )
- {
- int n;
-
-
- FT_TRACE7(( "y = %3d ", ras.span_y ));
- span = ras.gray_spans;
- for ( n = 0; n < count; n++, span++ )
- FT_TRACE7(( "[%d..%d]:%02x ",
- span->x, span->x + span->len - 1, span->coverage ));
- FT_TRACE7(( "\n" ));
- }
-
-#endif /* FT_DEBUG_LEVEL_TRACE */
-
- ras.num_gray_spans = 0;
- ras.span_y = (int)y;
-
- count = 0;
- span = ras.gray_spans;
- }
- else
- span++;
-
- /* add a gray span to the current list */
- span->x = (short)x;
- span->len = (unsigned short)acount;
- span->coverage = (unsigned char)coverage;
-
- ras.num_gray_spans++;
- }
- }
-
-
-#ifdef FT_DEBUG_LEVEL_TRACE
-
- /* to be called while in the debugger -- */
- /* this function causes a compiler warning since it is unused otherwise */
- static void
- gray_dump_cells( RAS_ARG )
- {
- int yindex;
-
-
- for ( yindex = 0; yindex < ras.ycount; yindex++ )
- {
- PCell cell;
-
-
- printf( "%3d:", yindex );
-
- for ( cell = ras.ycells[yindex]; cell != NULL; cell = cell->next )
- printf( " (%3ld, c:%4ld, a:%6d)", cell->x, cell->cover, cell->area );
- printf( "\n" );
- }
- }
-
-#endif /* FT_DEBUG_LEVEL_TRACE */
-
-
- static void
- gray_sweep( RAS_ARG_ const FT_Bitmap* target )
- {
- int yindex;
-
- FT_UNUSED( target );
-
-
- if ( ras.num_cells == 0 )
- return;
-
- ras.num_gray_spans = 0;
-
- FT_TRACE7(( "gray_sweep: start\n" ));
-
- for ( yindex = 0; yindex < ras.ycount; yindex++ )
- {
- PCell cell = ras.ycells[yindex];
- TCoord cover = 0;
- TCoord x = 0;
-
-
- for ( ; cell != NULL; cell = cell->next )
- {
- TPos area;
-
-
- if ( cell->x > x && cover != 0 )
- gray_hline( RAS_VAR_ x, yindex, cover * ( ONE_PIXEL * 2 ),
- cell->x - x );
-
- cover += cell->cover;
- area = cover * ( ONE_PIXEL * 2 ) - cell->area;
-
- if ( area != 0 && cell->x >= 0 )
- gray_hline( RAS_VAR_ cell->x, yindex, area, 1 );
-
- x = cell->x + 1;
- }
-
- if ( cover != 0 )
- gray_hline( RAS_VAR_ x, yindex, cover * ( ONE_PIXEL * 2 ),
- ras.count_ex - x );
- }
-
- if ( ras.render_span && ras.num_gray_spans > 0 )
- ras.render_span( ras.span_y, ras.num_gray_spans,
- ras.gray_spans, ras.render_span_data );
-
- FT_TRACE7(( "gray_sweep: end\n" ));
- }
-
-
-#ifdef _STANDALONE_
-
- /*************************************************************************/
- /* */
- /* The following function should only compile in stand-alone mode, */
- /* i.e., when building this component without the rest of FreeType. */
- /* */
- /*************************************************************************/
-
- /*************************************************************************/
- /* */
- /* <Function> */
- /* FT_Outline_Decompose */
- /* */
- /* <Description> */
- /* Walk over an outline's structure to decompose it into individual */
- /* segments and Bézier arcs. This function is also able to emit */
- /* `move to' and `close to' operations to indicate the start and end */
- /* of new contours in the outline. */
- /* */
- /* <Input> */
- /* outline :: A pointer to the source target. */
- /* */
- /* func_interface :: A table of `emitters', i.e., function pointers */
- /* called during decomposition to indicate path */
- /* operations. */
- /* */
- /* <InOut> */
- /* user :: A typeless pointer which is passed to each */
- /* emitter during the decomposition. It can be */
- /* used to store the state during the */
- /* decomposition. */
- /* */
- /* <Return> */
- /* Error code. 0 means success. */
- /* */
- static int
- FT_Outline_Decompose( const FT_Outline* outline,
- const FT_Outline_Funcs* func_interface,
- void* user )
- {
-#undef SCALED
-#define SCALED( x ) ( ( (x) << shift ) - delta )
-
- FT_Vector v_last;
- FT_Vector v_control;
- FT_Vector v_start;
-
- FT_Vector* point;
- FT_Vector* limit;
- char* tags;
-
- int error;
-
- int n; /* index of contour in outline */
- int first; /* index of first point in contour */
- char tag; /* current point's state */
-
- int shift;
- TPos delta;
-
-
- if ( !outline || !func_interface )
- return ErrRaster_Invalid_Argument;
-
- shift = func_interface->shift;
- delta = func_interface->delta;
- first = 0;
-
- for ( n = 0; n < outline->n_contours; n++ )
- {
- int last; /* index of last point in contour */
-
-
- FT_TRACE5(( "FT_Outline_Decompose: Outline %d\n", n ));
-
- last = outline->contours[n];
- if ( last < 0 )
- goto Invalid_Outline;
- limit = outline->points + last;
-
- v_start = outline->points[first];
- v_start.x = SCALED( v_start.x );
- v_start.y = SCALED( v_start.y );
-
- v_last = outline->points[last];
- v_last.x = SCALED( v_last.x );
- v_last.y = SCALED( v_last.y );
-
- v_control = v_start;
-
- point = outline->points + first;
- tags = outline->tags + first;
- tag = FT_CURVE_TAG( tags[0] );
-
- /* A contour cannot start with a cubic control point! */
- if ( tag == FT_CURVE_TAG_CUBIC )
- goto Invalid_Outline;
-
- /* check first point to determine origin */
- if ( tag == FT_CURVE_TAG_CONIC )
- {
- /* first point is conic control. Yes, this happens. */
- if ( FT_CURVE_TAG( outline->tags[last] ) == FT_CURVE_TAG_ON )
- {
- /* start at last point if it is on the curve */
- v_start = v_last;
- limit--;
- }
- else
- {
- /* if both first and last points are conic, */
- /* start at their middle and record its position */
- /* for closure */
- v_start.x = ( v_start.x + v_last.x ) / 2;
- v_start.y = ( v_start.y + v_last.y ) / 2;
-
- v_last = v_start;
- }
- point--;
- tags--;
- }
-
- FT_TRACE5(( " move to (%.2f, %.2f)\n",
- v_start.x / 64.0, v_start.y / 64.0 ));
- error = func_interface->move_to( &v_start, user );
- if ( error )
- goto Exit;
-
- while ( point < limit )
- {
- point++;
- tags++;
-
- tag = FT_CURVE_TAG( tags[0] );
- switch ( tag )
- {
- case FT_CURVE_TAG_ON: /* emit a single line_to */
- {
- FT_Vector vec;
-
-
- vec.x = SCALED( point->x );
- vec.y = SCALED( point->y );
-
- FT_TRACE5(( " line to (%.2f, %.2f)\n",
- vec.x / 64.0, vec.y / 64.0 ));
- error = func_interface->line_to( &vec, user );
- if ( error )
- goto Exit;
- continue;
- }
-
- case FT_CURVE_TAG_CONIC: /* consume conic arcs */
- v_control.x = SCALED( point->x );
- v_control.y = SCALED( point->y );
-
- Do_Conic:
- if ( point < limit )
- {
- FT_Vector vec;
- FT_Vector v_middle;
-
-
- point++;
- tags++;
- tag = FT_CURVE_TAG( tags[0] );
-
- vec.x = SCALED( point->x );
- vec.y = SCALED( point->y );
-
- if ( tag == FT_CURVE_TAG_ON )
- {
- FT_TRACE5(( " conic to (%.2f, %.2f)"
- " with control (%.2f, %.2f)\n",
- vec.x / 64.0, vec.y / 64.0,
- v_control.x / 64.0, v_control.y / 64.0 ));
- error = func_interface->conic_to( &v_control, &vec, user );
- if ( error )
- goto Exit;
- continue;
- }
-
- if ( tag != FT_CURVE_TAG_CONIC )
- goto Invalid_Outline;
-
- v_middle.x = ( v_control.x + vec.x ) / 2;
- v_middle.y = ( v_control.y + vec.y ) / 2;
-
- FT_TRACE5(( " conic to (%.2f, %.2f)"
- " with control (%.2f, %.2f)\n",
- v_middle.x / 64.0, v_middle.y / 64.0,
- v_control.x / 64.0, v_control.y / 64.0 ));
- error = func_interface->conic_to( &v_control, &v_middle, user );
- if ( error )
- goto Exit;
-
- v_control = vec;
- goto Do_Conic;
- }
-
- FT_TRACE5(( " conic to (%.2f, %.2f)"
- " with control (%.2f, %.2f)\n",
- v_start.x / 64.0, v_start.y / 64.0,
- v_control.x / 64.0, v_control.y / 64.0 ));
- error = func_interface->conic_to( &v_control, &v_start, user );
- goto Close;
-
- default: /* FT_CURVE_TAG_CUBIC */
- {
- FT_Vector vec1, vec2;
-
-
- if ( point + 1 > limit ||
- FT_CURVE_TAG( tags[1] ) != FT_CURVE_TAG_CUBIC )
- goto Invalid_Outline;
-
- point += 2;
- tags += 2;
-
- vec1.x = SCALED( point[-2].x );
- vec1.y = SCALED( point[-2].y );
-
- vec2.x = SCALED( point[-1].x );
- vec2.y = SCALED( point[-1].y );
-
- if ( point <= limit )
- {
- FT_Vector vec;
-
-
- vec.x = SCALED( point->x );
- vec.y = SCALED( point->y );
-
- FT_TRACE5(( " cubic to (%.2f, %.2f)"
- " with controls (%.2f, %.2f) and (%.2f, %.2f)\n",
- vec.x / 64.0, vec.y / 64.0,
- vec1.x / 64.0, vec1.y / 64.0,
- vec2.x / 64.0, vec2.y / 64.0 ));
- error = func_interface->cubic_to( &vec1, &vec2, &vec, user );
- if ( error )
- goto Exit;
- continue;
- }
-
- FT_TRACE5(( " cubic to (%.2f, %.2f)"
- " with controls (%.2f, %.2f) and (%.2f, %.2f)\n",
- v_start.x / 64.0, v_start.y / 64.0,
- vec1.x / 64.0, vec1.y / 64.0,
- vec2.x / 64.0, vec2.y / 64.0 ));
- error = func_interface->cubic_to( &vec1, &vec2, &v_start, user );
- goto Close;
- }
- }
- }
-
- /* close the contour with a line segment */
- FT_TRACE5(( " line to (%.2f, %.2f)\n",
- v_start.x / 64.0, v_start.y / 64.0 ));
- error = func_interface->line_to( &v_start, user );
-
- Close:
- if ( error )
- goto Exit;
-
- first = last + 1;
- }
-
- FT_TRACE5(( "FT_Outline_Decompose: Done\n", n ));
- return 0;
-
- Exit:
- FT_TRACE5(( "FT_Outline_Decompose: Error %d\n", error ));
- return error;
-
- Invalid_Outline:
- return ErrRaster_Invalid_Outline;
- }
-
-#endif /* _STANDALONE_ */
-
-
- typedef struct TBand_
- {
- TPos min, max;
-
- } TBand;
-
- FT_DEFINE_OUTLINE_FUNCS(func_interface,
- (FT_Outline_MoveTo_Func) gray_move_to,
- (FT_Outline_LineTo_Func) gray_line_to,
- (FT_Outline_ConicTo_Func)gray_conic_to,
- (FT_Outline_CubicTo_Func)gray_cubic_to,
- 0,
- 0
- )
-
- static int
- gray_convert_glyph_inner( RAS_ARG )
- {
-
- volatile int error = 0;
-
-#ifdef FT_CONFIG_OPTION_PIC
- FT_Outline_Funcs func_interface;
- Init_Class_func_interface(&func_interface);
-#endif
-
- if ( ft_setjmp( ras.jump_buffer ) == 0 )
- {
- error = FT_Outline_Decompose( &ras.outline, &func_interface, &ras );
- gray_record_cell( RAS_VAR );
- }
- else
- error = ErrRaster_Memory_Overflow;
-
- return error;
- }
-
-
- static int
- gray_convert_glyph( RAS_ARG )
- {
- TBand bands[40];
- TBand* volatile band;
- int volatile n, num_bands;
- TPos volatile min, max, max_y;
- FT_BBox* clip;
-
-
- /* Set up state in the raster object */
- gray_compute_cbox( RAS_VAR );
-
- /* clip to target bitmap, exit if nothing to do */
- clip = &ras.clip_box;
-
- if ( ras.max_ex <= clip->xMin || ras.min_ex >= clip->xMax ||
- ras.max_ey <= clip->yMin || ras.min_ey >= clip->yMax )
- return 0;
-
- if ( ras.min_ex < clip->xMin ) ras.min_ex = clip->xMin;
- if ( ras.min_ey < clip->yMin ) ras.min_ey = clip->yMin;
-
- if ( ras.max_ex > clip->xMax ) ras.max_ex = clip->xMax;
- if ( ras.max_ey > clip->yMax ) ras.max_ey = clip->yMax;
-
- ras.count_ex = ras.max_ex - ras.min_ex;
- ras.count_ey = ras.max_ey - ras.min_ey;
-
- /* set up vertical bands */
- num_bands = (int)( ( ras.max_ey - ras.min_ey ) / ras.band_size );
- if ( num_bands == 0 )
- num_bands = 1;
- if ( num_bands >= 39 )
- num_bands = 39;
-
- ras.band_shoot = 0;
-
- min = ras.min_ey;
- max_y = ras.max_ey;
-
- for ( n = 0; n < num_bands; n++, min = max )
- {
- max = min + ras.band_size;
- if ( n == num_bands - 1 || max > max_y )
- max = max_y;
-
- bands[0].min = min;
- bands[0].max = max;
- band = bands;
-
- while ( band >= bands )
- {
- TPos bottom, top, middle;
- int error;
-
- {
- PCell cells_max;
- int yindex;
- long cell_start, cell_end, cell_mod;
-
-
- ras.ycells = (PCell*)ras.buffer;
- ras.ycount = band->max - band->min;
-
- cell_start = sizeof ( PCell ) * ras.ycount;
- cell_mod = cell_start % sizeof ( TCell );
- if ( cell_mod > 0 )
- cell_start += sizeof ( TCell ) - cell_mod;
-
- cell_end = ras.buffer_size;
- cell_end -= cell_end % sizeof( TCell );
-
- cells_max = (PCell)( (char*)ras.buffer + cell_end );
- ras.cells = (PCell)( (char*)ras.buffer + cell_start );
- if ( ras.cells >= cells_max )
- goto ReduceBands;
-
- ras.max_cells = cells_max - ras.cells;
- if ( ras.max_cells < 2 )
- goto ReduceBands;
-
- for ( yindex = 0; yindex < ras.ycount; yindex++ )
- ras.ycells[yindex] = NULL;
- }
-
- ras.num_cells = 0;
- ras.invalid = 1;
- ras.min_ey = band->min;
- ras.max_ey = band->max;
- ras.count_ey = band->max - band->min;
-
- error = gray_convert_glyph_inner( RAS_VAR );
-
- if ( !error )
- {
- gray_sweep( RAS_VAR_ &ras.target );
- band--;
- continue;
- }
- else if ( error != ErrRaster_Memory_Overflow )
- return 1;
-
- ReduceBands:
- /* render pool overflow; we will reduce the render band by half */
- bottom = band->min;
- top = band->max;
- middle = bottom + ( ( top - bottom ) >> 1 );
-
- /* This is too complex for a single scanline; there must */
- /* be some problems. */
- if ( middle == bottom )
- {
-#ifdef FT_DEBUG_LEVEL_TRACE
- FT_TRACE7(( "gray_convert_glyph: rotten glyph\n" ));
-#endif
- return 1;
- }
-
- if ( bottom-top >= ras.band_size )
- ras.band_shoot++;
-
- band[1].min = bottom;
- band[1].max = middle;
- band[0].min = middle;
- band[0].max = top;
- band++;
- }
- }
-
- if ( ras.band_shoot > 8 && ras.band_size > 16 )
- ras.band_size = ras.band_size / 2;
-
- return 0;
- }
-
-
- static int
- gray_raster_render( PRaster raster,
- const FT_Raster_Params* params )
- {
- const FT_Outline* outline = (const FT_Outline*)params->source;
- const FT_Bitmap* target_map = params->target;
- PWorker worker;
-
-
- if ( !raster || !raster->buffer || !raster->buffer_size )
- return ErrRaster_Invalid_Argument;
-
- if ( !outline )
- return ErrRaster_Invalid_Outline;
-
- /* return immediately if the outline is empty */
- if ( outline->n_points == 0 || outline->n_contours <= 0 )
- return 0;
-
- if ( !outline->contours || !outline->points )
- return ErrRaster_Invalid_Outline;
-
- if ( outline->n_points !=
- outline->contours[outline->n_contours - 1] + 1 )
- return ErrRaster_Invalid_Outline;
-
- worker = raster->worker;
-
- /* if direct mode is not set, we must have a target bitmap */
- if ( !( params->flags & FT_RASTER_FLAG_DIRECT ) )
- {
- if ( !target_map )
- return ErrRaster_Invalid_Argument;
-
- /* nothing to do */
- if ( !target_map->width || !target_map->rows )
- return 0;
-
- if ( !target_map->buffer )
- return ErrRaster_Invalid_Argument;
- }
-
- /* this version does not support monochrome rendering */
- if ( !( params->flags & FT_RASTER_FLAG_AA ) )
- return ErrRaster_Invalid_Mode;
-
- /* compute clipping box */
- if ( !( params->flags & FT_RASTER_FLAG_DIRECT ) )
- {
- /* compute clip box from target pixmap */
- ras.clip_box.xMin = 0;
- ras.clip_box.yMin = 0;
- ras.clip_box.xMax = target_map->width;
- ras.clip_box.yMax = target_map->rows;
- }
- else if ( params->flags & FT_RASTER_FLAG_CLIP )
- ras.clip_box = params->clip_box;
- else
- {
- ras.clip_box.xMin = -32768L;
- ras.clip_box.yMin = -32768L;
- ras.clip_box.xMax = 32767L;
- ras.clip_box.yMax = 32767L;
- }
-
- gray_init_cells( RAS_VAR_ raster->buffer, raster->buffer_size );
-
- ras.outline = *outline;
- ras.num_cells = 0;
- ras.invalid = 1;
- ras.band_size = raster->band_size;
- ras.num_gray_spans = 0;
-
- if ( params->flags & FT_RASTER_FLAG_DIRECT )
- {
- ras.render_span = (FT_Raster_Span_Func)params->gray_spans;
- ras.render_span_data = params->user;
- }
- else
- {
- ras.target = *target_map;
- ras.render_span = (FT_Raster_Span_Func)gray_render_span;
- ras.render_span_data = &ras;
- }
-
- return gray_convert_glyph( RAS_VAR );
- }
-
-
- /**** RASTER OBJECT CREATION: In stand-alone mode, we simply use *****/
- /**** a static object. *****/
-
-#ifdef _STANDALONE_
-
- static int
- gray_raster_new( void* memory,
- FT_Raster* araster )
- {
- static TRaster the_raster;
-
- FT_UNUSED( memory );
-
-
- *araster = (FT_Raster)&the_raster;
- FT_MEM_ZERO( &the_raster, sizeof ( the_raster ) );
-
- return 0;
- }
-
-
- static void
- gray_raster_done( FT_Raster raster )
- {
- /* nothing */
- FT_UNUSED( raster );
- }
-
-#else /* !_STANDALONE_ */
-
- static int
- gray_raster_new( FT_Memory memory,
- FT_Raster* araster )
- {
- FT_Error error;
- PRaster raster = NULL;
-
-
- *araster = 0;
- if ( !FT_ALLOC( raster, sizeof ( TRaster ) ) )
- {
- raster->memory = memory;
- *araster = (FT_Raster)raster;
- }
-
- return error;
- }
-
-
- static void
- gray_raster_done( FT_Raster raster )
- {
- FT_Memory memory = (FT_Memory)((PRaster)raster)->memory;
-
-
- FT_FREE( raster );
- }
-
-#endif /* !_STANDALONE_ */
-
-
- static void
- gray_raster_reset( FT_Raster raster,
- char* pool_base,
- long pool_size )
- {
- PRaster rast = (PRaster)raster;
-
-
- if ( raster )
- {
- if ( pool_base && pool_size >= (long)sizeof ( TWorker ) + 2048 )
- {
- PWorker worker = (PWorker)pool_base;
-
-
- rast->worker = worker;
- rast->buffer = pool_base +
- ( ( sizeof ( TWorker ) + sizeof ( TCell ) - 1 ) &
- ~( sizeof ( TCell ) - 1 ) );
- rast->buffer_size = (long)( ( pool_base + pool_size ) -
- (char*)rast->buffer ) &
- ~( sizeof ( TCell ) - 1 );
- rast->band_size = (int)( rast->buffer_size /
- ( sizeof ( TCell ) * 8 ) );
- }
- else
- {
- rast->buffer = NULL;
- rast->buffer_size = 0;
- rast->worker = NULL;
- }
- }
- }
-
-
- FT_DEFINE_RASTER_FUNCS(ft_grays_raster,
- FT_GLYPH_FORMAT_OUTLINE,
-
- (FT_Raster_New_Func) gray_raster_new,
- (FT_Raster_Reset_Func) gray_raster_reset,
- (FT_Raster_Set_Mode_Func)0,
- (FT_Raster_Render_Func) gray_raster_render,
- (FT_Raster_Done_Func) gray_raster_done
- )
-
-
-/* END */
-
-
-/* Local Variables: */
-/* coding: utf-8 */
-/* End: */