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- /***************************************************************************/
- /* */
- /* ftgrays.c */
- /* */
- /* A new `perfect' anti-aliasing renderer (body). */
- /* */
- /* Copyright 2000-2001, 2002 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. */
- /* */
- /*************************************************************************/
- /* experimental support for gamma correction within the rasterizer */
- #define xxxGRAYS_USE_GAMMA
- /*************************************************************************/
- /* */
- /* 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
- #define ErrRaster_MemoryOverflow -4
- #ifdef _STANDALONE_
- #include <string.h> /* for ft_memcpy() */
- #include <setjmp.h>
- #include <limits.h>
- #define FT_UINT_MAX UINT_MAX
- #define ft_memset memset
- #define ft_setjmp setjmp
- #define ft_longjmp longjmp
- #define ft_jmp_buf jmp_buf
- #define ErrRaster_Invalid_Mode -2
- #define ErrRaster_Invalid_Outline -1
- #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)
- /* 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_ */
- #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
- /* 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 ) ( (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
- /* 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. */
- #undef GRAYS_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 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_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 */
- #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
- #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_
- {
- TCoord x;
- TCoord y;
- int cover;
- TArea area;
- } TCell, *PCell;
- #endif /* GRAYS_COMPACT */
- typedef struct TRaster_
- {
- PCell cells;
- int max_cells;
- int num_cells;
- TPos min_ex, max_ex;
- TPos min_ey, max_ey;
- TArea area;
- int cover;
- int invalid;
- TCoord ex, ey;
- 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;
- int conic_level;
- int cubic_level;
- void* memory;
- ft_jmp_buf jump_buffer;
- #ifdef GRAYS_USE_GAMMA
- unsigned char gamma[257];
- #endif
- } 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 )
- ft_longjmp( ras.jump_buffer, 1 );
- cell = ras.cells + ras.num_cells++;
- cell->x = (TCoord)(ras.ex - ras.min_ex);
- cell->y = (TCoord)(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_ TCoord ex,
- TCoord 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 = (TCoord)(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_ TCoord ex,
- TCoord ey )
- {
- if ( ex < ras.min_ex )
- ex = (TCoord)(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_ TCoord ey,
- TPos x1,
- TCoord y1,
- TPos x2,
- TCoord y2 )
- {
- TCoord 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 = (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 -= 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;
- TPos dx, dy, x, x2;
- long p, first;
- int delta, rem, mod, 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 );
- TPos 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( raster, 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( raster, 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_ 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++ )
- {
- unsigned char coverage = spans->coverage;
- #ifdef GRAYS_USE_GAMMA
- coverage = raster->gamma[coverage];
- #endif
- if ( coverage )
- #if 1
- FT_MEM_SET( p + spans->x, (unsigned char)coverage, spans->len );
- #else /* 1 */
- {
- q = p + spans->x;
- limit = q + spans->len;
- for ( ; q < limit; q++ )
- q[0] = (unsigned char)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_ TCoord x,
- TCoord 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 = (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;
- 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 )
- {
- TCoord 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 ),
- (int)( 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. */
- /* */
- /* func_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* func_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 = func_interface->shift;
- TPos delta = func_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 = 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 );
- 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 )
- {
- 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;
- error = func_interface->conic_to( &v_control, &v_middle, user );
- if ( error )
- goto Exit;
- v_control = vec;
- goto Do_Conic;
- }
- 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 );
- error = func_interface->cubic_to( &vec1, &vec2, &vec, user );
- if ( error )
- goto Exit;
- continue;
- }
- error = func_interface->cubic_to( &vec1, &vec2, &v_start, user );
- goto Close;
- }
- }
- }
- /* close the contour with a line segment */
- error = func_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_
- {
- TPos min, max;
- } TBand;
- static int
- gray_convert_glyph_inner( RAS_ARG )
- {
- static
- const FT_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
- };
- volatile int error = 0;
- if ( ft_setjmp( ras.jump_buffer ) == 0 )
- {
- error = FT_Outline_Decompose( &ras.outline, &func_interface, &ras );
- gray_record_cell( RAS_VAR );
- }
- else
- {
- error = ErrRaster_MemoryOverflow;
- }
- return error;
- }
- static int
- gray_convert_glyph( RAS_ARG )
- {
- TBand bands[40];
- volatile TBand* band;
- volatile int n, num_bands;
- volatile 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 = (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;
- 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, &func_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 GRAYS_USE_GAMMA
- /* initialize the "gamma" table. Yes, this is really a crummy function */
- /* but the results look pretty good for something that simple. */
- /* */
- #define M_MAX 255
- #define M_X 128
- #define M_Y 192
- static void
- grays_init_gamma( PRaster raster )
- {
- unsigned int x, a;
- for ( x = 0; x < 256; x++ )
- {
- if ( x <= M_X )
- a = ( x * M_Y + M_X / 2) / M_X;
- else
- a = M_Y + ( ( x - M_X ) * ( M_MAX - M_Y ) +
- ( M_MAX - M_X ) / 2 ) / ( M_MAX - M_X );
- raster->gamma[x] = (unsigned char)a;
- }
- }
- #endif /* GRAYS_USE_GAMMA */
- #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 ) );
- #ifdef GRAYS_USE_GAMMA
- grays_init_gamma( (PRaster)*araster );
- #endif
- 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 ( !FT_ALLOC( raster, sizeof ( TRaster ) ) )
- {
- raster->memory = memory;
- *araster = (FT_Raster)raster;
- #ifdef GRAYS_USE_GAMMA
- grays_init_gamma( raster );
- #endif
- }
- 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,
- 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 = (int)( ( 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 */
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