--- /dev/null
+/***************************************************************************/
+/* */
+/* ftgrays.c */
+/* */
+/* A new `perfect' anti-aliasing renderer (body). */
+/* */
+/* Copyright 2000-2001 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/base/ftgrays.c' to your current directory */
+ /* */
+ /* - copy `include/freetype/ftimage.h' and */
+ /* `include/freetype/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.gray_raster_new'; an anti-aliased bitmap can be */
+ /* generated with a call to `ft_gray_raster.gray_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. */
+ /* */
+ /*************************************************************************/
+
+
+#include <string.h> /* for memcpy() */
+#include <setjmp.h>
+
+ /*************************************************************************/
+ /* */
+ /* 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_aaraster
+
+
+#define ErrRaster_MemoryOverflow -4
+
+#ifdef _STANDALONE_
+
+
+#define ErrRaster_Invalid_Mode -2
+#define ErrRaster_Invalid_Outline -1
+
+#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)
+
+ /* Disable the tracing mechanism for simplicity -- developers can */
+ /* activate it easily by redefining these two macros. */
+#ifndef FT_ERROR
+#define FT_ERROR( x ) do ; while ( 0 ) /* nothing */
+#endif
+
+#ifndef FT_TRACE
+#define FT_TRACE( x ) do ; while ( 0 ) /* nothing */
+#endif
+
+
+#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"
+
+#define ErrRaster_Invalid_Mode Smooth_Err_Cannot_Render_Glyph
+#define ErrRaster_Invalid_Outline Smooth_Err_Invalid_Outline
+
+
+#endif /* _STANDALONE_ */
+
+
+ /* define this to dump debugging information */
+#define xxxDEBUG_GRAYS
+
+ /* as usual, for the speed hungry :-) */
+
+#ifndef FT_STATIC_RASTER
+
+
+#define RAS_ARG PRaster raster
+#define RAS_ARG_ PRaster raster,
+
+#define RAS_VAR raster
+#define RAS_VAR_ raster,
+
+#define ras (*raster)
+
+
+#else /* FT_STATIC_RASTER */
+
+
+#define RAS_ARG /* empty */
+#define RAS_ARG_ /* empty */
+#define RAS_VAR /* empty */
+#define RAS_VAR_ /* empty */
+
+ static TRaster ras;
+
+
+#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 ) ( (x) >> PIXEL_BITS )
+#define SUBPIXELS( x ) ( (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
+
+ /* Define this if you want to use a more compact storage scheme. This */
+ /* increases the number of cells available in the render pool but slows */
+ /* down the rendering a bit. It is useful if you have a really tiny */
+ /* render pool. */
+#define xxxGRAYS_COMPACT
+
+
+ /*************************************************************************/
+ /* */
+ /* 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 int TScan; /* integer scanline/pixel coordinate */
+ typedef long TPos; /* sub-pixel coordinate */
+
+ /* determine the type used to store cell areas. This normally takes at */
+ /* least PIXEL_BYTES*2 + 1. 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 */
+#include <limits.h>
+
+#if 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
+
+
+#ifdef GRAYS_COMPACT
+
+ typedef struct TCell_
+ {
+ short x : 14;
+ short y : 14;
+ int cover : PIXEL_BITS + 2;
+ int area : PIXEL_BITS * 2 + 2;
+
+ } TCell, *PCell;
+
+#else /* GRAYS_COMPACT */
+
+ typedef struct TCell_
+ {
+ TScan x;
+ TScan y;
+ int cover;
+ TArea area;
+
+ } TCell, *PCell;
+
+#endif /* GRAYS_COMPACT */
+
+
+ typedef struct TRaster_
+ {
+ PCell cells;
+ int max_cells;
+ int num_cells;
+
+ TScan min_ex, max_ex;
+ TScan min_ey, max_ey;
+
+ TArea area;
+ int cover;
+ int invalid;
+
+ TScan ex, ey;
+ TScan cx, cy;
+ TPos x, y;
+
+ TScan 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;
+ int conic_level;
+ int cubic_level;
+
+ void* memory;
+ jmp_buf jump_buffer;
+
+ } TRaster, *PRaster;
+
+
+ /*************************************************************************/
+ /* */
+ /* Initialize the cells table. */
+ /* */
+ static void
+ gray_init_cells( RAS_ARG_ void* buffer,
+ long byte_size )
+ {
+ ras.cells = (PCell)buffer;
+ ras.max_cells = byte_size / sizeof ( TCell );
+ 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 void
+ gray_record_cell( RAS_ARG )
+ {
+ PCell cell;
+
+
+ if ( !ras.invalid && ( ras.area | ras.cover ) )
+ {
+ if ( ras.num_cells >= ras.max_cells )
+ longjmp( ras.jump_buffer, 1 );
+
+ cell = ras.cells + ras.num_cells++;
+ cell->x = ras.ex - ras.min_ex;
+ cell->y = ras.ey - ras.min_ey;
+ cell->area = ras.area;
+ cell->cover = ras.cover;
+ }
+ }
+
+
+ /*************************************************************************/
+ /* */
+ /* Set the current cell to a new position. */
+ /* */
+ static void
+ gray_set_cell( RAS_ARG_ TScan ex,
+ TScan ey )
+ {
+ int invalid, record, clean;
+
+
+ /* 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. */
+
+ record = 0;
+ clean = 1;
+
+ invalid = ( ey < ras.min_ey || ey >= ras.max_ey || ex >= ras.max_ex );
+ if ( !invalid )
+ {
+ /* All cells that are on the left of the clipping region go to the */
+ /* min_ex - 1 horizontal position. */
+ if ( ex < ras.min_ex )
+ ex = ras.min_ex - 1;
+
+ /* if our position is new, then record the previous cell */
+ if ( ex != ras.ex || ey != ras.ey )
+ record = 1;
+ else
+ clean = ras.invalid; /* do not clean if we didn't move from */
+ /* a valid cell */
+ }
+
+ /* record the previous cell if needed (i.e., if we changed the cell */
+ /* position, of changed the `invalid' flag) */
+ if ( ras.invalid != invalid || record )
+ gray_record_cell( RAS_VAR );
+
+ if ( clean )
+ {
+ ras.area = 0;
+ ras.cover = 0;
+ }
+
+ ras.invalid = invalid;
+ ras.ex = ex;
+ ras.ey = ey;
+ }
+
+
+ /*************************************************************************/
+ /* */
+ /* Start a new contour at a given cell. */
+ /* */
+ static void
+ gray_start_cell( RAS_ARG_ TScan ex,
+ TScan ey )
+ {
+ if ( ex < ras.min_ex )
+ ex = ras.min_ex - 1;
+
+ ras.area = 0;
+ ras.cover = 0;
+ ras.ex = ex;
+ ras.ey = 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_ TScan ey,
+ TPos x1,
+ TScan y1,
+ TPos x2,
+ TScan y2 )
+ {
+ TScan ex1, ex2, fx1, fx2, delta;
+ long p, first, dx;
+ int incr, lift, mod, rem;
+
+
+ dx = x2 - x1;
+
+ ex1 = TRUNC( x1 ); /* if (ex1 >= ras.max_ex) ex1 = ras.max_ex-1; */
+ ex2 = TRUNC( x2 ); /* if (ex2 >= ras.max_ex) ex2 = ras.max_ex-1; */
+ fx1 = x1 - SUBPIXELS( ex1 );
+ fx2 = 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 = p / dx;
+ mod = p % dx;
+ if ( mod < 0 )
+ {
+ delta--;
+ mod += 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 );
+ lift = p / dx;
+ rem = p % dx;
+ if ( rem < 0 )
+ {
+ lift--;
+ rem += dx;
+ }
+
+ mod -= dx;
+
+ while ( ex1 != ex2 )
+ {
+ delta = lift;
+ mod += rem;
+ if ( mod >= 0 )
+ {
+ mod -= 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 )
+ {
+ TScan ey1, ey2, fy1, fy2;
+ TPos dx, dy, x, x2;
+ int p, rem, mod, lift, delta, first, incr;
+
+
+ ey1 = TRUNC( ras.last_ey );
+ ey2 = TRUNC( to_y ); /* if (ey2 >= ras.max_ey) ey2 = ras.max_ey-1; */
+ fy1 = ras.y - ras.last_ey;
+ fy2 = 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 */
+ {
+ TScan 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;
+ }
+
+ /* 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 = p / dy;
+ mod = p % dy;
+ if ( mod < 0 )
+ {
+ delta--;
+ mod += dy;
+ }
+
+ x = ras.x + delta;
+ gray_render_scanline( RAS_VAR_ ey1, ras.x, fy1, x, first );
+
+ ey1 += incr;
+ gray_set_cell( RAS_VAR_ TRUNC( x ), ey1 );
+
+ if ( ey1 != ey2 )
+ {
+ p = ONE_PIXEL * dx;
+ lift = p / dy;
+ rem = p % dy;
+ if ( rem < 0 )
+ {
+ lift--;
+ rem += dy;
+ }
+ mod -= dy;
+
+ while ( ey1 != ey2 )
+ {
+ delta = lift;
+ mod += rem;
+ if ( mod >= 0 )
+ {
+ mod -= dy;
+ delta++;
+ }
+
+ x2 = x + delta;
+ gray_render_scanline( RAS_VAR_ ey1, x, ONE_PIXEL - first, x2, first );
+ x = x2;
+
+ ey1 += incr;
+ gray_set_cell( RAS_VAR_ TRUNC( x ), ey1 );
+ }
+ }
+
+ gray_render_scanline( RAS_VAR_ ey1, x, 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_ FT_Vector* control,
+ FT_Vector* to )
+ {
+ TPos dx, dy;
+ int top, level;
+ int* levels;
+ FT_Vector* arc;
+
+
+ dx = DOWNSCALE( ras.x ) + to->x - ( control->x << 1 );
+ if ( dx < 0 )
+ dx = -dx;
+ dy = DOWNSCALE( ras.y ) + to->y - ( control->y << 1 );
+ if ( dy < 0 )
+ dy = -dy;
+ if ( dx < dy )
+ dx = dy;
+
+ level = 1;
+ dx = dx / ras.conic_level;
+ while ( dx > 0 )
+ {
+ dx >>= 2;
+ level++;
+ }
+
+ /* a shortcut to speed things up */
+ if ( level <= 1 )
+ {
+ /* we compute the mid-point directly in order to avoid */
+ /* calling gray_split_conic() */
+ TPos to_x, to_y, mid_x, mid_y;
+
+
+ to_x = UPSCALE( to->x );
+ to_y = UPSCALE( to->y );
+ mid_x = ( ras.x + to_x + 2 * UPSCALE( control->x ) ) / 4;
+ mid_y = ( ras.y + to_y + 2 * UPSCALE( control->y ) ) / 4;
+
+ gray_render_line( RAS_VAR_ mid_x, mid_y );
+ gray_render_line( RAS_VAR_ to_x, to_y );
+ return;
+ }
+
+ arc = ras.bez_stack;
+ levels = ras.lev_stack;
+ top = 0;
+ levels[0] = level;
+
+ 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;
+
+ while ( top >= 0 )
+ {
+ 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 ) < 0 )
+ goto Draw;
+
+ gray_split_conic( arc );
+ arc += 2;
+ top++;
+ levels[top] = levels[top - 1] = level - 1;
+ continue;
+ }
+
+ Draw:
+ {
+ TPos to_x, to_y, mid_x, mid_y;
+
+
+ to_x = arc[0].x;
+ to_y = arc[0].y;
+ mid_x = ( ras.x + to_x + 2 * arc[1].x ) / 4;
+ mid_y = ( ras.y + to_y + 2 * arc[1].y ) / 4;
+
+ gray_render_line( RAS_VAR_ mid_x, mid_y );
+ gray_render_line( RAS_VAR_ to_x, to_y );
+
+ top--;
+ arc -= 2;
+ }
+ }
+ return;
+ }
+
+
+ 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_ FT_Vector* control1,
+ FT_Vector* control2,
+ FT_Vector* to )
+ {
+ TPos dx, dy, da, db;
+ int top, level;
+ int* levels;
+ FT_Vector* arc;
+
+
+ dx = DOWNSCALE( ras.x ) + to->x - ( control1->x << 1 );
+ if ( dx < 0 )
+ dx = -dx;
+ dy = DOWNSCALE( ras.y ) + to->y - ( control1->y << 1 );
+ if ( dy < 0 )
+ dy = -dy;
+ if ( dx < dy )
+ dx = dy;
+ da = dx;
+
+ dx = DOWNSCALE( ras.x ) + to->x - 3 * ( control1->x + control2->x );
+ if ( dx < 0 )
+ dx = -dx;
+ dy = DOWNSCALE( ras.y ) + to->y - 3 * ( control1->x + control2->y );
+ if ( dy < 0 )
+ dy = -dy;
+ if ( dx < dy )
+ dx = dy;
+ db = dx;
+
+ level = 1;
+ da = da / ras.cubic_level;
+ db = db / ras.conic_level;
+ while ( da > 0 || db > 0 )
+ {
+ da >>= 2;
+ db >>= 3;
+ level++;
+ }
+
+ if ( level <= 1 )
+ {
+ TPos to_x, to_y, mid_x, mid_y;
+
+
+ to_x = UPSCALE( to->x );
+ to_y = UPSCALE( to->y );
+ mid_x = ( ras.x + to_x +
+ 3 * UPSCALE( control1->x + control2->x ) ) / 8;
+ mid_y = ( ras.y + to_y +
+ 3 * UPSCALE( control1->y + control2->y ) ) / 8;
+
+ gray_render_line( RAS_VAR_ mid_x, mid_y );
+ gray_render_line( RAS_VAR_ to_x, to_y );
+ return;
+ }
+
+ 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;
+
+ levels = ras.lev_stack;
+ top = 0;
+ levels[0] = level;
+
+ while ( top >= 0 )
+ {
+ 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;
+ y = arc[3].y;
+ if ( y < min ) min = y;
+ if ( y > max ) max = y;
+ if ( TRUNC( min ) >= ras.max_ey || TRUNC( max ) < 0 )
+ goto Draw;
+ gray_split_cubic( arc );
+ arc += 3;
+ top ++;
+ levels[top] = levels[top - 1] = level - 1;
+ continue;
+ }
+
+ Draw:
+ {
+ TPos to_x, to_y, mid_x, mid_y;
+
+
+ to_x = arc[0].x;
+ to_y = arc[0].y;
+ mid_x = ( ras.x + to_x + 3 * ( arc[1].x + arc[2].x ) ) / 8;
+ mid_y = ( ras.y + to_y + 3 * ( arc[1].y + arc[2].y ) ) / 8;
+
+ gray_render_line( RAS_VAR_ mid_x, mid_y );
+ gray_render_line( RAS_VAR_ to_x, to_y );
+ top --;
+ arc -= 3;
+ }
+ }
+ return;
+ }
+
+
+ /* a macro comparing two cell pointers. Returns true if a <= b. */
+#if 1
+
+#define PACK( a ) ( ( (long)(a)->y << 16 ) + (a)->x )
+#define LESS_THAN( a, b ) ( PACK( a ) < PACK( b ) )
+
+#else /* 1 */
+
+#define LESS_THAN( a, b ) ( (a)->y < (b)->y || \
+ ( (a)->y == (b)->y && (a)->x < (b)->x ) )
+
+#endif /* 1 */
+
+#define SWAP_CELLS( a, b, temp ) do \
+ { \
+ temp = *(a); \
+ *(a) = *(b); \
+ *(b) = temp; \
+ } while ( 0 )
+#define DEBUG_SORT
+#define QUICK_SORT
+
+#ifdef SHELL_SORT
+
+ /* a simple shell sort algorithm that works directly on our */
+ /* cells table */
+ static void
+ gray_shell_sort ( PCell cells,
+ int count )
+ {
+ PCell i, j, limit = cells + count;
+ TCell temp;
+ int gap;
+
+
+ /* compute initial gap */
+ for ( gap = 0; ++gap < count; gap *= 3 )
+ ;
+
+ while ( gap /= 3 )
+ {
+ for ( i = cells + gap; i < limit; i++ )
+ {
+ for ( j = i - gap; ; j -= gap )
+ {
+ PCell k = j + gap;
+
+
+ if ( LESS_THAN( j, k ) )
+ break;
+
+ SWAP_CELLS( j, k, temp );
+
+ if ( j < cells + gap )
+ break;
+ }
+ }
+ }
+ }
+
+#endif /* SHELL_SORT */
+
+
+#ifdef QUICK_SORT
+
+ /* This is a non-recursive quicksort that directly process our cells */
+ /* array. It should be faster than calling the stdlib qsort(), and we */
+ /* can even tailor our insertion threshold... */
+
+#define QSORT_THRESHOLD 9 /* below this size, a sub-array will be sorted */
+ /* through a normal insertion sort */
+
+ static void
+ gray_quick_sort( PCell cells,
+ int count )
+ {
+ PCell stack[40]; /* should be enough ;-) */
+ PCell* top; /* top of stack */
+ PCell base, limit;
+ TCell temp;
+
+
+ limit = cells + count;
+ base = cells;
+ top = stack;
+
+ for (;;)
+ {
+ int len = (int)( limit - base );
+ PCell i, j, pivot;
+
+
+ if ( len > QSORT_THRESHOLD )
+ {
+ /* we use base + len/2 as the pivot */
+ pivot = base + len / 2;
+ SWAP_CELLS( base, pivot, temp );
+
+ i = base + 1;
+ j = limit - 1;
+
+ /* now ensure that *i <= *base <= *j */
+ if ( LESS_THAN( j, i ) )
+ SWAP_CELLS( i, j, temp );
+
+ if ( LESS_THAN( base, i ) )
+ SWAP_CELLS( base, i, temp );
+
+ if ( LESS_THAN( j, base ) )
+ SWAP_CELLS( base, j, temp );
+
+ for (;;)
+ {
+ do i++; while ( LESS_THAN( i, base ) );
+ do j--; while ( LESS_THAN( base, j ) );
+
+ if ( i > j )
+ break;
+
+ SWAP_CELLS( i, j, temp );
+ }
+
+ SWAP_CELLS( base, j, temp );
+
+ /* now, push the largest sub-array */
+ if ( j - base > limit - i )
+ {
+ top[0] = base;
+ top[1] = j;
+ base = i;
+ }
+ else
+ {
+ top[0] = i;
+ top[1] = limit;
+ limit = j;
+ }
+ top += 2;
+ }
+ else
+ {
+ /* the sub-array is small, perform insertion sort */
+ j = base;
+ i = j + 1;
+
+ for ( ; i < limit; j = i, i++ )
+ {
+ for ( ; LESS_THAN( j + 1, j ); j-- )
+ {
+ SWAP_CELLS( j + 1, j, temp );
+ if ( j == base )
+ break;
+ }
+ }
+ if ( top > stack )
+ {
+ top -= 2;
+ base = top[0];
+ limit = top[1];
+ }
+ else
+ break;
+ }
+ }
+ }
+
+#endif /* QUICK_SORT */
+
+
+#ifdef DEBUG_GRAYS
+#ifdef DEBUG_SORT
+
+ static int
+ gray_check_sort( PCell cells,
+ int count )
+ {
+ PCell p, q;
+
+
+ for ( p = cells + count - 2; p >= cells; p-- )
+ {
+ q = p + 1;
+ if ( !LESS_THAN( p, q ) )
+ return 0;
+ }
+ return 1;
+ }
+
+#endif /* DEBUG_SORT */
+#endif /* DEBUG_GRAYS */
+
+
+ static int
+ gray_move_to( FT_Vector* to,
+ FT_Raster raster )
+ {
+ TPos x, y;
+
+
+ /* record current cell, if any */
+ gray_record_cell( (PRaster)raster );
+
+ /* start to a new position */
+ x = UPSCALE( to->x );
+ y = UPSCALE( to->y );
+
+ gray_start_cell( (PRaster)raster, TRUNC( x ), TRUNC( y ) );
+
+ ((PRaster)raster)->x = x;
+ ((PRaster)raster)->y = y;
+ return 0;
+ }
+
+
+ static int
+ gray_line_to( FT_Vector* to,
+ FT_Raster raster )
+ {
+ gray_render_line( (PRaster)raster,
+ UPSCALE( to->x ), UPSCALE( to->y ) );
+ return 0;
+ }
+
+
+ static int
+ gray_conic_to( FT_Vector* control,
+ FT_Vector* to,
+ FT_Raster raster )
+ {
+ gray_render_conic( (PRaster)raster, control, to );
+ return 0;
+ }
+
+
+ static int
+ gray_cubic_to( FT_Vector* control1,
+ FT_Vector* control2,
+ FT_Vector* to,
+ FT_Raster raster )
+ {
+ gray_render_cubic( (PRaster)raster, control1, control2, to );
+ return 0;
+ }
+
+
+ static void
+ gray_render_span( int y,
+ int count,
+ FT_Span* spans,
+ PRaster raster )
+ {
+ unsigned char* p;
+ FT_Bitmap* map = &raster->target;
+
+
+ /* first of all, compute the scanline offset */
+ p = (unsigned char*)map->buffer - y * map->pitch;
+ if ( map->pitch >= 0 )
+ p += ( map->rows - 1 ) * map->pitch;
+
+ for ( ; count > 0; count--, spans++ )
+ {
+ if ( spans->coverage )
+#if 1
+ memset( p + spans->x, (unsigned char)spans->coverage, spans->len );
+#else /* 1 */
+ {
+ q = p + spans->x;
+ limit = q + spans->len;
+ for ( ; q < limit; q++ )
+ q[0] = (unsigned char)spans->coverage;
+ }
+#endif /* 1 */
+ }
+ }
+
+
+#ifdef DEBUG_GRAYS
+
+#include <stdio.h>
+
+ static void
+ gray_dump_cells( RAS_ARG )
+ {
+ PCell cell, limit;
+ int y = -1;
+
+
+ cell = ras.cells;
+ limit = cell + ras.num_cells;
+
+ for ( ; cell < limit; cell++ )
+ {
+ if ( cell->y != y )
+ {
+ fprintf( stderr, "\n%2d: ", cell->y );
+ y = cell->y;
+ }
+ fprintf( stderr, "[%d %d %d]",
+ cell->x, cell->area, cell->cover );
+ }
+ fprintf(stderr, "\n" );
+ }
+
+#endif /* DEBUG_GRAYS */
+
+
+ static void
+ gray_hline( RAS_ARG_ TScan x,
+ TScan y,
+ TPos area,
+ int 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 = area >> ( PIXEL_BITS * 2 + 1 - 8); /* use range 0..256 */
+
+ if ( ras.outline.flags & ft_outline_even_odd_fill )
+ {
+ if ( coverage < 0 )
+ coverage = -coverage;
+
+ while ( coverage >= 512 )
+ coverage -= 512;
+
+ if ( coverage > 256 )
+ coverage = 512 - coverage;
+ else if ( coverage == 256 )
+ coverage = 255;
+ }
+ else
+ {
+ /* normal non-zero winding rule */
+ if ( coverage < 0 )
+ coverage = -coverage;
+
+ if ( coverage >= 256 )
+ coverage = 255;
+ }
+
+ y += ras.min_ey;
+ x += ras.min_ex;
+
+ if ( coverage )
+ {
+ /* see if 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 );
+ /* ras.render_span( span->y, ras.gray_spans, count ); */
+
+#ifdef DEBUG_GRAYS
+
+ if ( ras.span_y >= 0 )
+ {
+ int n;
+
+
+ fprintf( stderr, "y=%3d ", ras.span_y );
+ span = ras.gray_spans;
+ for ( n = 0; n < count; n++, span++ )
+ fprintf( stderr, "[%d..%d]:%02x ",
+ span->x, span->x + span->len - 1, span->coverage );
+ fprintf( stderr, "\n" );
+ }
+
+#endif /* DEBUG_GRAYS */
+
+ ras.num_gray_spans = 0;
+ ras.span_y = 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++;
+ }
+ }
+
+
+ static void
+ gray_sweep( RAS_ARG_ FT_Bitmap* target )
+ {
+ TScan x, y, cover;
+ TArea area;
+ PCell start, cur, limit;
+
+ FT_UNUSED( target );
+
+ if ( ras.num_cells == 0 )
+ return;
+
+ cur = ras.cells;
+ limit = cur + ras.num_cells;
+
+ cover = 0;
+ ras.span_y = -1;
+ ras.num_gray_spans = 0;
+
+ for (;;)
+ {
+ start = cur;
+ y = start->y;
+ x = start->x;
+
+ area = start->area;
+ cover += start->cover;
+
+ /* accumulate all start cells */
+ for (;;)
+ {
+ ++cur;
+ if ( cur >= limit || cur->y != start->y || cur->x != start->x )
+ break;
+
+ area += cur->area;
+ cover += cur->cover;
+ }
+
+ /* if the start cell has a non-null area, we must draw an */
+ /* individual gray pixel there */
+ if ( area && x >= 0 )
+ {
+ gray_hline( RAS_VAR_ x, y, cover * ( ONE_PIXEL * 2 ) - area, 1 );
+ x++;
+ }
+
+ if ( x < 0 )
+ x = 0;
+
+ if ( cur < limit && start->y == cur->y )
+ {
+ /* draw a gray span between the start cell and the current one */
+ if ( cur->x > x )
+ gray_hline( RAS_VAR_ x, y,
+ cover * ( ONE_PIXEL * 2 ), cur->x - x );
+ }
+ else
+ {
+ /* draw a gray span until the end of the clipping region */
+ if ( cover && x < ras.max_ex - ras.min_ex )
+ gray_hline( RAS_VAR_ x, y,
+ cover * ( ONE_PIXEL * 2 ),
+ ras.max_ex - x - ras.min_ex );
+ cover = 0;
+ }
+
+ if ( cur >= limit )
+ break;
+ }
+
+ 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 );
+
+#ifdef DEBUG_GRAYS
+
+ {
+ int n;
+ FT_Span* span;
+
+
+ fprintf( stderr, "y=%3d ", ras.span_y );
+ span = ras.gray_spans;
+ for ( n = 0; n < ras.num_gray_spans; n++, span++ )
+ fprintf( stderr, "[%d..%d]:%02x ",
+ span->x, span->x + span->len - 1, span->coverage );
+ fprintf( stderr, "\n" );
+ }
+
+#endif /* DEBUG_GRAYS */
+
+ }
+
+
+#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> */
+ /* Walks over an outline's structure to decompose it into individual */
+ /* segments and Bezier 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. */
+ /* */
+ /* interface :: A table of `emitters', i.e,. function pointers called */
+ /* during decomposition to indicate path operations. */
+ /* */
+ /* 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 sucess. */
+ /* */
+ static
+ int FT_Outline_Decompose( FT_Outline* outline,
+ const FT_Outline_Funcs* interface,
+ void* user )
+ {
+#undef SCALED
+#if 0
+#define SCALED( x ) ( ( (x) << shift ) - delta )
+#else
+#define SCALED( x ) (x)
+#endif
+
+ FT_Vector v_last;
+ FT_Vector v_control;
+ FT_Vector v_start;
+
+ FT_Vector* point;
+ FT_Vector* limit;
+ char* tags;
+
+ int n; /* index of contour in outline */
+ int first; /* index of first point in contour */
+ int error;
+ char tag; /* current point's state */
+
+#if 0
+ int shift = interface->shift;
+ FT_Pos delta = interface->delta;
+#endif
+
+
+ first = 0;
+
+ for ( n = 0; n < outline->n_contours; n++ )
+ {
+ int last; /* index of last point in contour */
+
+
+ last = outline->contours[n];
+ limit = outline->points + last;
+
+ v_start = outline->points[first];
+ v_last = outline->points[last];
+
+ v_start.x = SCALED( v_start.x ); v_start.y = SCALED( v_start.y );
+ 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--;
+ }
+
+ error = 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 );
+
+ error = 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 )
+ {
+ error = 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;
+
+ error = interface->conic_to( &v_control, &v_middle, user );
+ if ( error )
+ goto Exit;
+
+ v_control = vec;
+ goto Do_Conic;
+ }
+
+ error = 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 );
+
+ error = interface->cubic_to( &vec1, &vec2, &vec, user );
+ if ( error )
+ goto Exit;
+ continue;
+ }
+
+ error = interface->cubic_to( &vec1, &vec2, &v_start, user );
+ goto Close;
+ }
+ }
+ }
+
+ /* close the contour with a line segment */
+ error = interface->line_to( &v_start, user );
+
+ Close:
+ if ( error )
+ goto Exit;
+
+ first = last + 1;
+ }
+
+ return 0;
+
+ Exit:
+ return error;
+
+ Invalid_Outline:
+ return ErrRaster_Invalid_Outline;
+ }
+
+#endif /* _STANDALONE_ */
+
+
+ typedef struct TBand_
+ {
+ FT_Pos min, max;
+
+ } TBand;
+
+
+ static int
+ gray_convert_glyph_inner( RAS_ARG )
+ {
+ static
+ const FT_Outline_Funcs 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
+ };
+
+ volatile int error = 0;
+
+ if ( setjmp( ras.jump_buffer ) == 0 )
+ {
+ error = FT_Outline_Decompose( &ras.outline, &interface, &ras );
+ gray_record_cell( RAS_VAR );
+ }
+ else
+ {
+ error = ErrRaster_MemoryOverflow;
+ }
+
+ return error;
+ }
+
+
+ static int
+ gray_convert_glyph( RAS_ARG )
+ {
+ TBand bands[40], *band;
+ int n, num_bands;
+ TPos 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;
+
+ /* simple heuristic used to speed-up the bezier decomposition -- see */
+ /* the code in gray_render_conic() and gray_render_cubic() for more */
+ /* details */
+ ras.conic_level = 32;
+ ras.cubic_level = 16;
+
+ {
+ int level = 0;
+
+
+ if ( ras.max_ex > 24 || ras.max_ey > 24 )
+ level++;
+ if ( ras.max_ex > 120 || ras.max_ey > 120 )
+ level++;
+
+ ras.conic_level <<= level;
+ ras.cubic_level <<= level;
+ }
+
+ /* setup vertical bands */
+ num_bands = ( 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 )
+ {
+ FT_Pos bottom, top, middle;
+ int error;
+
+
+ ras.num_cells = 0;
+ ras.invalid = 1;
+ ras.min_ey = band->min;
+ ras.max_ey = band->max;
+
+#if 1
+ error = gray_convert_glyph_inner( RAS_VAR );
+#else
+ error = FT_Outline_Decompose( outline, &interface, &ras ) ||
+ gray_record_cell( RAS_VAR );
+#endif
+
+ if ( !error )
+ {
+#ifdef SHELL_SORT
+ gray_shell_sort( ras.cells, ras.num_cells );
+#else
+ gray_quick_sort( ras.cells, ras.num_cells );
+#endif
+
+#ifdef DEBUG_GRAYS
+ gray_check_sort( ras.cells, ras.num_cells );
+ gray_dump_cells( RAS_VAR );
+#endif
+
+ gray_sweep( RAS_VAR_ &ras.target );
+ band--;
+ continue;
+ }
+ else if ( error != ErrRaster_MemoryOverflow )
+ return 1;
+
+ /* render pool overflow, we will reduce the render band by half */
+ bottom = band->min;
+ top = band->max;
+ middle = bottom + ( ( top - bottom ) >> 1 );
+
+ /* waoow! This is too complex for a single scanline, something */
+ /* must be really rotten here! */
+ if ( middle == bottom )
+ {
+#ifdef DEBUG_GRAYS
+ fprintf( stderr, "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;
+ }
+
+
+ extern int
+ gray_raster_render( PRaster raster,
+ FT_Raster_Params* params )
+ {
+ FT_Outline* outline = (FT_Outline*)params->source;
+ FT_Bitmap* target_map = params->target;
+
+
+ if ( !raster || !raster->cells || !raster->max_cells )
+ return -1;
+
+ /* return immediately if the outline is empty */
+ if ( outline->n_points == 0 || outline->n_contours <= 0 )
+ return 0;
+
+ if ( !outline || !outline->contours || !outline->points )
+ return ErrRaster_Invalid_Outline;
+
+ if ( outline->n_points !=
+ outline->contours[outline->n_contours - 1] + 1 )
+ return ErrRaster_Invalid_Outline;
+
+ /* if direct mode is not set, we must have a target bitmap */
+ if ( ( params->flags & ft_raster_flag_direct ) == 0 &&
+ ( !target_map || !target_map->buffer ) )
+ return -1;
+
+ /* 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 ) == 0 )
+ {
+ /* 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;
+ }
+
+ ras.outline = *outline;
+ ras.num_cells = 0;
+ ras.invalid = 1;
+
+ if ( target_map )
+ ras.target = *target_map;
+
+ ras.render_span = (FT_Raster_Span_Func)gray_render_span;
+ ras.render_span_data = &ras;
+
+ if ( params->flags & ft_raster_flag_direct )
+ {
+ ras.render_span = (FT_Raster_Span_Func)params->gray_spans;
+ ras.render_span_data = params->user;
+ }
+
+ return gray_convert_glyph( (PRaster)raster );
+ }
+
+
+ /**** RASTER OBJECT CREATION: In standalone 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;
+ memset( &the_raster, 0, 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;
+
+
+ *araster = 0;
+ if ( !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;
+
+
+ FREE( raster );
+ }
+
+#endif /* _STANDALONE_ */
+
+
+ static void
+ gray_raster_reset( FT_Raster raster,
+ const char* pool_base,
+ long pool_size )
+ {
+ PRaster rast = (PRaster)raster;
+
+
+ if ( raster && pool_base && pool_size >= 4096 )
+ gray_init_cells( rast, (char*)pool_base, pool_size );
+
+ rast->band_size = ( pool_size / sizeof ( TCell ) ) / 8;
+ }
+
+
+ const FT_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 */