| /***************************************************************************/ |
| /* */ |
| /* ftraster.c */ |
| /* */ |
| /* The FreeType glyph rasterizer (body). */ |
| /* */ |
| /* Copyright 1996-2003, 2005, 2007-2013 by */ |
| /* David Turner, Robert Wilhelm, and Werner Lemberg. */ |
| /* */ |
| /* This file is part of the FreeType project, and may only be used, */ |
| /* modified, and distributed under the terms of the FreeType project */ |
| /* license, LICENSE.TXT. By continuing to use, modify, or distribute */ |
| /* this file you indicate that you have read the license and */ |
| /* understand and accept it fully. */ |
| /* */ |
| /***************************************************************************/ |
| |
| /*************************************************************************/ |
| /* */ |
| /* 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 `ftimage.h' and `ftmisc.h' into the $(incdir) */ |
| /* directory. Typically, you should do something like */ |
| /* */ |
| /* - copy `src/raster/ftraster.c' (this file) to your current directory */ |
| /* */ |
| /* - copy `include/freetype/ftimage.h' and `src/raster/ftmisc.h' */ |
| /* to your current directory */ |
| /* */ |
| /* - compile `ftraster' with the _STANDALONE_ macro defined, as in */ |
| /* */ |
| /* cc -c -D_STANDALONE_ ftraster.c */ |
| /* */ |
| /* The renderer can be initialized with a call to */ |
| /* `ft_standard_raster.raster_new'; a bitmap can be generated */ |
| /* with a call to `ft_standard_raster.raster_render'. */ |
| /* */ |
| /* See the comments and documentation in the file `ftimage.h' for more */ |
| /* details on how the raster works. */ |
| /* */ |
| /*************************************************************************/ |
| |
| |
| /*************************************************************************/ |
| /* */ |
| /* This is a rewrite of the FreeType 1.x scan-line converter */ |
| /* */ |
| /*************************************************************************/ |
| |
| #ifdef _STANDALONE_ |
| |
| #define FT_CONFIG_STANDARD_LIBRARY_H <stdlib.h> |
| |
| #include <string.h> /* for memset */ |
| |
| #include "ftmisc.h" |
| #include "ftimage.h" |
| |
| #else /* !_STANDALONE_ */ |
| |
| #include "../../include/ft2build.h" |
| #include "ftraster.h" |
| #include "../../include/freetype/internal/ftcalc.h" /* for FT_MulDiv and FT_MulDiv_No_Round */ |
| |
| #include "rastpic.h" |
| |
| #endif /* !_STANDALONE_ */ |
| |
| |
| /*************************************************************************/ |
| /* */ |
| /* A simple technical note on how the raster works */ |
| /* ----------------------------------------------- */ |
| /* */ |
| /* Converting an outline into a bitmap is achieved in several steps: */ |
| /* */ |
| /* 1 - Decomposing the outline into successive `profiles'. Each */ |
| /* profile is simply an array of scanline intersections on a given */ |
| /* dimension. A profile's main attributes are */ |
| /* */ |
| /* o its scanline position boundaries, i.e. `Ymin' and `Ymax' */ |
| /* */ |
| /* o an array of intersection coordinates for each scanline */ |
| /* between `Ymin' and `Ymax' */ |
| /* */ |
| /* o a direction, indicating whether it was built going `up' or */ |
| /* `down', as this is very important for filling rules */ |
| /* */ |
| /* o its drop-out mode */ |
| /* */ |
| /* 2 - Sweeping the target map's scanlines in order to compute segment */ |
| /* `spans' which are then filled. Additionally, this pass */ |
| /* performs drop-out control. */ |
| /* */ |
| /* The outline data is parsed during step 1 only. The profiles are */ |
| /* built from the bottom of the render pool, used as a stack. The */ |
| /* following graphics shows the profile list under construction: */ |
| /* */ |
| /* __________________________________________________________ _ _ */ |
| /* | | | | | */ |
| /* | profile | coordinates for | profile | coordinates for |--> */ |
| /* | 1 | profile 1 | 2 | profile 2 |--> */ |
| /* |_________|_________________|_________|_________________|__ _ _ */ |
| /* */ |
| /* ^ ^ */ |
| /* | | */ |
| /* start of render pool top */ |
| /* */ |
| /* The top of the profile stack is kept in the `top' variable. */ |
| /* */ |
| /* As you can see, a profile record is pushed on top of the render */ |
| /* pool, which is then followed by its coordinates/intersections. If */ |
| /* a change of direction is detected in the outline, a new profile is */ |
| /* generated until the end of the outline. */ |
| /* */ |
| /* Note that when all profiles have been generated, the function */ |
| /* Finalize_Profile_Table() is used to record, for each profile, its */ |
| /* bottom-most scanline as well as the scanline above its upmost */ |
| /* boundary. These positions are called `y-turns' because they (sort */ |
| /* of) correspond to local extrema. They are stored in a sorted list */ |
| /* built from the top of the render pool as a downwards stack: */ |
| /* */ |
| /* _ _ _______________________________________ */ |
| /* | | */ |
| /* <--| sorted list of | */ |
| /* <--| extrema scanlines | */ |
| /* _ _ __________________|____________________| */ |
| /* */ |
| /* ^ ^ */ |
| /* | | */ |
| /* maxBuff sizeBuff = end of pool */ |
| /* */ |
| /* This list is later used during the sweep phase in order to */ |
| /* optimize performance (see technical note on the sweep below). */ |
| /* */ |
| /* Of course, the raster detects whether the two stacks collide and */ |
| /* handles the situation properly. */ |
| /* */ |
| /*************************************************************************/ |
| |
| |
| /*************************************************************************/ |
| /*************************************************************************/ |
| /** **/ |
| /** CONFIGURATION MACROS **/ |
| /** **/ |
| /*************************************************************************/ |
| /*************************************************************************/ |
| |
| /* define DEBUG_RASTER if you want to compile a debugging version */ |
| /* #define DEBUG_RASTER */ |
| |
| /* define FT_RASTER_OPTION_ANTI_ALIASING if you want to support */ |
| /* 5-levels anti-aliasing */ |
| /* #define FT_RASTER_OPTION_ANTI_ALIASING */ |
| |
| /* The size of the two-lines intermediate bitmap used */ |
| /* for anti-aliasing, in bytes. */ |
| #define RASTER_GRAY_LINES 2048 |
| |
| |
| /*************************************************************************/ |
| /*************************************************************************/ |
| /** **/ |
| /** OTHER MACROS (do not change) **/ |
| /** **/ |
| /*************************************************************************/ |
| /*************************************************************************/ |
| |
| /*************************************************************************/ |
| /* */ |
| /* 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_raster |
| |
| |
| #ifdef _STANDALONE_ |
| |
| /* Auxiliary macros for token concatenation. */ |
| #define FT_ERR_XCAT( x, y ) x ## y |
| #define FT_ERR_CAT( x, y ) FT_ERR_XCAT( x, y ) |
| |
| /* 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 macros. */ |
| #ifndef FT_ERROR |
| #define FT_ERROR( x ) do { } while ( 0 ) /* nothing */ |
| #endif |
| |
| #ifndef FT_TRACE |
| #define FT_TRACE( x ) do { } while ( 0 ) /* nothing */ |
| #define FT_TRACE1( x ) do { } while ( 0 ) /* nothing */ |
| #define FT_TRACE6( x ) do { } while ( 0 ) /* nothing */ |
| #endif |
| |
| #ifndef FT_THROW |
| #define FT_THROW( e ) FT_ERR_CAT( Raster_Err_, e ) |
| #endif |
| |
| #define Raster_Err_None 0 |
| #define Raster_Err_Not_Ini -1 |
| #define Raster_Err_Overflow -2 |
| #define Raster_Err_Neg_Height -3 |
| #define Raster_Err_Invalid -4 |
| #define Raster_Err_Unsupported -5 |
| |
| #define ft_memset memset |
| |
| #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 "../../include/freetype/internal/ftobjs.h" |
| #include "../../include/freetype/internal/ftdebug.h" /* for FT_TRACE, FT_ERROR, and FT_THROW */ |
| |
| #include "rasterrs.h" |
| |
| #define Raster_Err_None FT_Err_Ok |
| #define Raster_Err_Not_Ini Raster_Err_Raster_Uninitialized |
| #define Raster_Err_Overflow Raster_Err_Raster_Overflow |
| #define Raster_Err_Neg_Height Raster_Err_Raster_Negative_Height |
| #define Raster_Err_Invalid Raster_Err_Invalid_Outline |
| #define Raster_Err_Unsupported Raster_Err_Cannot_Render_Glyph |
| |
| |
| #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 |
| |
| /* FMulDiv means `Fast MulDiv'; it is used in case where `b' is */ |
| /* typically a small value and the result of a*b is known to fit into */ |
| /* 32 bits. */ |
| #define FMulDiv( a, b, c ) ( (a) * (b) / (c) ) |
| |
| /* On the other hand, SMulDiv means `Slow MulDiv', and is used typically */ |
| /* for clipping computations. It simply uses the FT_MulDiv() function */ |
| /* defined in `ftcalc.h'. */ |
| #define SMulDiv FT_MulDiv |
| #define SMulDiv_No_Round FT_MulDiv_No_Round |
| |
| /* The rasterizer is a very general purpose component; please leave */ |
| /* the following redefinitions there (you never know your target */ |
| /* environment). */ |
| |
| #ifndef TRUE |
| #define TRUE 1 |
| #endif |
| |
| #ifndef FALSE |
| #define FALSE 0 |
| #endif |
| |
| #ifndef NULL |
| #define NULL (void*)0 |
| #endif |
| |
| #ifndef SUCCESS |
| #define SUCCESS 0 |
| #endif |
| |
| #ifndef FAILURE |
| #define FAILURE 1 |
| #endif |
| |
| |
| #define MaxBezier 32 /* The maximum number of stacked Bezier curves. */ |
| /* Setting this constant to more than 32 is a */ |
| /* pure waste of space. */ |
| |
| #define Pixel_Bits 6 /* fractional bits of *input* coordinates */ |
| |
| |
| /*************************************************************************/ |
| /*************************************************************************/ |
| /** **/ |
| /** SIMPLE TYPE DECLARATIONS **/ |
| /** **/ |
| /*************************************************************************/ |
| /*************************************************************************/ |
| |
| typedef int Int; |
| typedef unsigned int UInt; |
| typedef short Short; |
| typedef unsigned short UShort, *PUShort; |
| typedef long Long, *PLong; |
| typedef unsigned long ULong; |
| |
| typedef unsigned char Byte, *PByte; |
| typedef char Bool; |
| |
| |
| typedef union Alignment_ |
| { |
| long l; |
| void* p; |
| void (*f)(void); |
| |
| } Alignment, *PAlignment; |
| |
| |
| typedef struct TPoint_ |
| { |
| Long x; |
| Long y; |
| |
| } TPoint; |
| |
| |
| /* values for the `flags' bit field */ |
| #define Flow_Up 0x8 |
| #define Overshoot_Top 0x10 |
| #define Overshoot_Bottom 0x20 |
| |
| |
| /* States of each line, arc, and profile */ |
| typedef enum TStates_ |
| { |
| Unknown_State, |
| Ascending_State, |
| Descending_State, |
| Flat_State |
| |
| } TStates; |
| |
| |
| typedef struct TProfile_ TProfile; |
| typedef TProfile* PProfile; |
| |
| struct TProfile_ |
| { |
| FT_F26Dot6 X; /* current coordinate during sweep */ |
| PProfile link; /* link to next profile (various purposes) */ |
| PLong offset; /* start of profile's data in render pool */ |
| unsigned flags; /* Bit 0-2: drop-out mode */ |
| /* Bit 3: profile orientation (up/down) */ |
| /* Bit 4: is top profile? */ |
| /* Bit 5: is bottom profile? */ |
| long height; /* profile's height in scanlines */ |
| long start; /* profile's starting scanline */ |
| |
| unsigned countL; /* number of lines to step before this */ |
| /* profile becomes drawable */ |
| |
| PProfile next; /* next profile in same contour, used */ |
| /* during drop-out control */ |
| }; |
| |
| typedef PProfile TProfileList; |
| typedef PProfile* PProfileList; |
| |
| |
| /* Simple record used to implement a stack of bands, required */ |
| /* by the sub-banding mechanism */ |
| typedef struct black_TBand_ |
| { |
| Short y_min; /* band's minimum */ |
| Short y_max; /* band's maximum */ |
| |
| } black_TBand; |
| |
| |
| #define AlignProfileSize \ |
| ( ( sizeof ( TProfile ) + sizeof ( Alignment ) - 1 ) / sizeof ( long ) ) |
| |
| |
| #undef RAS_ARG |
| #undef RAS_ARGS |
| #undef RAS_VAR |
| #undef RAS_VARS |
| |
| #ifdef FT_STATIC_RASTER |
| |
| |
| #define RAS_ARGS /* void */ |
| #define RAS_ARG /* void */ |
| |
| #define RAS_VARS /* void */ |
| #define RAS_VAR /* void */ |
| |
| #define FT_UNUSED_RASTER do { } while ( 0 ) |
| |
| |
| #else /* !FT_STATIC_RASTER */ |
| |
| |
| #define RAS_ARGS black_PWorker worker, |
| #define RAS_ARG black_PWorker worker |
| |
| #define RAS_VARS worker, |
| #define RAS_VAR worker |
| |
| #define FT_UNUSED_RASTER FT_UNUSED( worker ) |
| |
| |
| #endif /* !FT_STATIC_RASTER */ |
| |
| |
| typedef struct black_TWorker_ black_TWorker, *black_PWorker; |
| |
| |
| /* prototypes used for sweep function dispatch */ |
| typedef void |
| Function_Sweep_Init( RAS_ARGS Short* min, |
| Short* max ); |
| |
| typedef void |
| Function_Sweep_Span( RAS_ARGS Short y, |
| FT_F26Dot6 x1, |
| FT_F26Dot6 x2, |
| PProfile left, |
| PProfile right ); |
| |
| typedef void |
| Function_Sweep_Step( RAS_ARG ); |
| |
| |
| /* NOTE: These operations are only valid on 2's complement processors */ |
| #undef FLOOR |
| #undef CEILING |
| #undef TRUNC |
| #undef SCALED |
| |
| #define FLOOR( x ) ( (x) & -ras.precision ) |
| #define CEILING( x ) ( ( (x) + ras.precision - 1 ) & -ras.precision ) |
| #define TRUNC( x ) ( (Long)(x) >> ras.precision_bits ) |
| #define FRAC( x ) ( (x) & ( ras.precision - 1 ) ) |
| #define SCALED( x ) ( ( (ULong)(x) << ras.scale_shift ) - ras.precision_half ) |
| |
| #define IS_BOTTOM_OVERSHOOT( x ) \ |
| (Bool)( CEILING( x ) - x >= ras.precision_half ) |
| #define IS_TOP_OVERSHOOT( x ) \ |
| (Bool)( x - FLOOR( x ) >= ras.precision_half ) |
| |
| /* The most used variables are positioned at the top of the structure. */ |
| /* Thus, their offset can be coded with less opcodes, resulting in a */ |
| /* smaller executable. */ |
| |
| struct black_TWorker_ |
| { |
| Int precision_bits; /* precision related variables */ |
| Int precision; |
| Int precision_half; |
| Int precision_shift; |
| Int precision_step; |
| Int precision_jitter; |
| |
| Int scale_shift; /* == precision_shift for bitmaps */ |
| /* == precision_shift+1 for pixmaps */ |
| |
| PLong buff; /* The profiles buffer */ |
| PLong sizeBuff; /* Render pool size */ |
| PLong maxBuff; /* Profiles buffer size */ |
| PLong top; /* Current cursor in buffer */ |
| |
| FT_Error error; |
| |
| Int numTurns; /* number of Y-turns in outline */ |
| |
| TPoint* arc; /* current Bezier arc pointer */ |
| |
| UShort bWidth; /* target bitmap width */ |
| PByte bTarget; /* target bitmap buffer */ |
| PByte gTarget; /* target pixmap buffer */ |
| |
| Long lastX, lastY; |
| Long minY, maxY; |
| |
| UShort num_Profs; /* current number of profiles */ |
| |
| Bool fresh; /* signals a fresh new profile which */ |
| /* `start' field must be completed */ |
| Bool joint; /* signals that the last arc ended */ |
| /* exactly on a scanline. Allows */ |
| /* removal of doublets */ |
| PProfile cProfile; /* current profile */ |
| PProfile fProfile; /* head of linked list of profiles */ |
| PProfile gProfile; /* contour's first profile in case */ |
| /* of impact */ |
| |
| TStates state; /* rendering state */ |
| |
| FT_Bitmap target; /* description of target bit/pixmap */ |
| FT_Outline outline; |
| |
| Long traceOfs; /* current offset in target bitmap */ |
| Long traceG; /* current offset in target pixmap */ |
| |
| Short traceIncr; /* sweep's increment in target bitmap */ |
| |
| Short gray_min_x; /* current min x during gray rendering */ |
| Short gray_max_x; /* current max x during gray rendering */ |
| |
| /* dispatch variables */ |
| |
| Function_Sweep_Init* Proc_Sweep_Init; |
| Function_Sweep_Span* Proc_Sweep_Span; |
| Function_Sweep_Span* Proc_Sweep_Drop; |
| Function_Sweep_Step* Proc_Sweep_Step; |
| |
| Byte dropOutControl; /* current drop_out control method */ |
| |
| Bool second_pass; /* indicates whether a horizontal pass */ |
| /* should be performed to control */ |
| /* drop-out accurately when calling */ |
| /* Render_Glyph. Note that there is */ |
| /* no horizontal pass during gray */ |
| /* rendering. */ |
| |
| TPoint arcs[3 * MaxBezier + 1]; /* The Bezier stack */ |
| |
| black_TBand band_stack[16]; /* band stack used for sub-banding */ |
| Int band_top; /* band stack top */ |
| |
| #ifdef FT_RASTER_OPTION_ANTI_ALIASING |
| |
| Byte* grays; |
| |
| Byte gray_lines[RASTER_GRAY_LINES]; |
| /* Intermediate table used to render the */ |
| /* graylevels pixmaps. */ |
| /* gray_lines is a buffer holding two */ |
| /* monochrome scanlines */ |
| |
| Short gray_width; /* width in bytes of one monochrome */ |
| /* intermediate scanline of gray_lines. */ |
| /* Each gray pixel takes 2 bits long there */ |
| |
| /* The gray_lines must hold 2 lines, thus with size */ |
| /* in bytes of at least `gray_width*2'. */ |
| |
| #endif /* FT_RASTER_ANTI_ALIASING */ |
| |
| }; |
| |
| |
| typedef struct black_TRaster_ |
| { |
| char* buffer; |
| long buffer_size; |
| void* memory; |
| black_PWorker worker; |
| Byte grays[5]; |
| Short gray_width; |
| |
| } black_TRaster, *black_PRaster; |
| |
| #ifdef FT_STATIC_RASTER |
| |
| static black_TWorker cur_ras; |
| #define ras cur_ras |
| |
| #else /* !FT_STATIC_RASTER */ |
| |
| #define ras (*worker) |
| |
| #endif /* !FT_STATIC_RASTER */ |
| |
| |
| #ifdef FT_RASTER_OPTION_ANTI_ALIASING |
| |
| /* A lookup table used to quickly count set bits in four gray 2x2 */ |
| /* cells. The values of the table have been produced with the */ |
| /* following code: */ |
| /* */ |
| /* for ( i = 0; i < 256; i++ ) */ |
| /* { */ |
| /* l = 0; */ |
| /* j = i; */ |
| /* */ |
| /* for ( c = 0; c < 4; c++ ) */ |
| /* { */ |
| /* l <<= 4; */ |
| /* */ |
| /* if ( j & 0x80 ) l++; */ |
| /* if ( j & 0x40 ) l++; */ |
| /* */ |
| /* j = ( j << 2 ) & 0xFF; */ |
| /* } */ |
| /* printf( "0x%04X", l ); */ |
| /* } */ |
| /* */ |
| |
| static const short count_table[256] = |
| { |
| 0x0000, 0x0001, 0x0001, 0x0002, 0x0010, 0x0011, 0x0011, 0x0012, |
| 0x0010, 0x0011, 0x0011, 0x0012, 0x0020, 0x0021, 0x0021, 0x0022, |
| 0x0100, 0x0101, 0x0101, 0x0102, 0x0110, 0x0111, 0x0111, 0x0112, |
| 0x0110, 0x0111, 0x0111, 0x0112, 0x0120, 0x0121, 0x0121, 0x0122, |
| 0x0100, 0x0101, 0x0101, 0x0102, 0x0110, 0x0111, 0x0111, 0x0112, |
| 0x0110, 0x0111, 0x0111, 0x0112, 0x0120, 0x0121, 0x0121, 0x0122, |
| 0x0200, 0x0201, 0x0201, 0x0202, 0x0210, 0x0211, 0x0211, 0x0212, |
| 0x0210, 0x0211, 0x0211, 0x0212, 0x0220, 0x0221, 0x0221, 0x0222, |
| 0x1000, 0x1001, 0x1001, 0x1002, 0x1010, 0x1011, 0x1011, 0x1012, |
| 0x1010, 0x1011, 0x1011, 0x1012, 0x1020, 0x1021, 0x1021, 0x1022, |
| 0x1100, 0x1101, 0x1101, 0x1102, 0x1110, 0x1111, 0x1111, 0x1112, |
| 0x1110, 0x1111, 0x1111, 0x1112, 0x1120, 0x1121, 0x1121, 0x1122, |
| 0x1100, 0x1101, 0x1101, 0x1102, 0x1110, 0x1111, 0x1111, 0x1112, |
| 0x1110, 0x1111, 0x1111, 0x1112, 0x1120, 0x1121, 0x1121, 0x1122, |
| 0x1200, 0x1201, 0x1201, 0x1202, 0x1210, 0x1211, 0x1211, 0x1212, |
| 0x1210, 0x1211, 0x1211, 0x1212, 0x1220, 0x1221, 0x1221, 0x1222, |
| 0x1000, 0x1001, 0x1001, 0x1002, 0x1010, 0x1011, 0x1011, 0x1012, |
| 0x1010, 0x1011, 0x1011, 0x1012, 0x1020, 0x1021, 0x1021, 0x1022, |
| 0x1100, 0x1101, 0x1101, 0x1102, 0x1110, 0x1111, 0x1111, 0x1112, |
| 0x1110, 0x1111, 0x1111, 0x1112, 0x1120, 0x1121, 0x1121, 0x1122, |
| 0x1100, 0x1101, 0x1101, 0x1102, 0x1110, 0x1111, 0x1111, 0x1112, |
| 0x1110, 0x1111, 0x1111, 0x1112, 0x1120, 0x1121, 0x1121, 0x1122, |
| 0x1200, 0x1201, 0x1201, 0x1202, 0x1210, 0x1211, 0x1211, 0x1212, |
| 0x1210, 0x1211, 0x1211, 0x1212, 0x1220, 0x1221, 0x1221, 0x1222, |
| 0x2000, 0x2001, 0x2001, 0x2002, 0x2010, 0x2011, 0x2011, 0x2012, |
| 0x2010, 0x2011, 0x2011, 0x2012, 0x2020, 0x2021, 0x2021, 0x2022, |
| 0x2100, 0x2101, 0x2101, 0x2102, 0x2110, 0x2111, 0x2111, 0x2112, |
| 0x2110, 0x2111, 0x2111, 0x2112, 0x2120, 0x2121, 0x2121, 0x2122, |
| 0x2100, 0x2101, 0x2101, 0x2102, 0x2110, 0x2111, 0x2111, 0x2112, |
| 0x2110, 0x2111, 0x2111, 0x2112, 0x2120, 0x2121, 0x2121, 0x2122, |
| 0x2200, 0x2201, 0x2201, 0x2202, 0x2210, 0x2211, 0x2211, 0x2212, |
| 0x2210, 0x2211, 0x2211, 0x2212, 0x2220, 0x2221, 0x2221, 0x2222 |
| }; |
| |
| #endif /* FT_RASTER_OPTION_ANTI_ALIASING */ |
| |
| |
| |
| /*************************************************************************/ |
| /*************************************************************************/ |
| /** **/ |
| /** PROFILES COMPUTATION **/ |
| /** **/ |
| /*************************************************************************/ |
| /*************************************************************************/ |
| |
| |
| /*************************************************************************/ |
| /* */ |
| /* <Function> */ |
| /* Set_High_Precision */ |
| /* */ |
| /* <Description> */ |
| /* Set precision variables according to param flag. */ |
| /* */ |
| /* <Input> */ |
| /* High :: Set to True for high precision (typically for ppem < 24), */ |
| /* false otherwise. */ |
| /* */ |
| static void |
| Set_High_Precision( RAS_ARGS Int High ) |
| { |
| /* |
| * `precision_step' is used in `Bezier_Up' to decide when to split a |
| * given y-monotonous Bezier arc that crosses a scanline before |
| * approximating it as a straight segment. The default value of 32 (for |
| * low accuracy) corresponds to |
| * |
| * 32 / 64 == 0.5 pixels , |
| * |
| * while for the high accuracy case we have |
| * |
| * 256/ (1 << 12) = 0.0625 pixels . |
| * |
| * `precision_jitter' is an epsilon threshold used in |
| * `Vertical_Sweep_Span' to deal with small imperfections in the Bezier |
| * decomposition (after all, we are working with approximations only); |
| * it avoids switching on additional pixels which would cause artifacts |
| * otherwise. |
| * |
| * The value of `precision_jitter' has been determined heuristically. |
| * |
| */ |
| |
| if ( High ) |
| { |
| ras.precision_bits = 12; |
| ras.precision_step = 256; |
| ras.precision_jitter = 30; |
| } |
| else |
| { |
| ras.precision_bits = 6; |
| ras.precision_step = 32; |
| ras.precision_jitter = 2; |
| } |
| |
| FT_TRACE6(( "Set_High_Precision(%s)\n", High ? "true" : "false" )); |
| |
| ras.precision = 1 << ras.precision_bits; |
| ras.precision_half = ras.precision / 2; |
| ras.precision_shift = ras.precision_bits - Pixel_Bits; |
| } |
| |
| |
| /*************************************************************************/ |
| /* */ |
| /* <Function> */ |
| /* New_Profile */ |
| /* */ |
| /* <Description> */ |
| /* Create a new profile in the render pool. */ |
| /* */ |
| /* <Input> */ |
| /* aState :: The state/orientation of the new profile. */ |
| /* */ |
| /* overshoot :: Whether the profile's unrounded start position */ |
| /* differs by at least a half pixel. */ |
| /* */ |
| /* <Return> */ |
| /* SUCCESS on success. FAILURE in case of overflow or of incoherent */ |
| /* profile. */ |
| /* */ |
| static Bool |
| New_Profile( RAS_ARGS TStates aState, |
| Bool overshoot ) |
| { |
| if ( !ras.fProfile ) |
| { |
| ras.cProfile = (PProfile)ras.top; |
| ras.fProfile = ras.cProfile; |
| ras.top += AlignProfileSize; |
| } |
| |
| if ( ras.top >= ras.maxBuff ) |
| { |
| ras.error = FT_THROW( Overflow ); |
| return FAILURE; |
| } |
| |
| ras.cProfile->flags = 0; |
| ras.cProfile->start = 0; |
| ras.cProfile->height = 0; |
| ras.cProfile->offset = ras.top; |
| ras.cProfile->link = (PProfile)0; |
| ras.cProfile->next = (PProfile)0; |
| ras.cProfile->flags = ras.dropOutControl; |
| |
| switch ( aState ) |
| { |
| case Ascending_State: |
| ras.cProfile->flags |= Flow_Up; |
| if ( overshoot ) |
| ras.cProfile->flags |= Overshoot_Bottom; |
| |
| FT_TRACE6(( "New ascending profile = %p\n", ras.cProfile )); |
| break; |
| |
| case Descending_State: |
| if ( overshoot ) |
| ras.cProfile->flags |= Overshoot_Top; |
| FT_TRACE6(( "New descending profile = %p\n", ras.cProfile )); |
| break; |
| |
| default: |
| FT_ERROR(( "New_Profile: invalid profile direction\n" )); |
| ras.error = FT_THROW( Invalid ); |
| return FAILURE; |
| } |
| |
| if ( !ras.gProfile ) |
| ras.gProfile = ras.cProfile; |
| |
| ras.state = aState; |
| ras.fresh = TRUE; |
| ras.joint = FALSE; |
| |
| return SUCCESS; |
| } |
| |
| |
| /*************************************************************************/ |
| /* */ |
| /* <Function> */ |
| /* End_Profile */ |
| /* */ |
| /* <Description> */ |
| /* Finalize the current profile. */ |
| /* */ |
| /* <Input> */ |
| /* overshoot :: Whether the profile's unrounded end position differs */ |
| /* by at least a half pixel. */ |
| /* */ |
| /* <Return> */ |
| /* SUCCESS on success. FAILURE in case of overflow or incoherency. */ |
| /* */ |
| static Bool |
| End_Profile( RAS_ARGS Bool overshoot ) |
| { |
| Long h; |
| |
| |
| h = (Long)( ras.top - ras.cProfile->offset ); |
| |
| if ( h < 0 ) |
| { |
| FT_ERROR(( "End_Profile: negative height encountered\n" )); |
| ras.error = FT_THROW( Neg_Height ); |
| return FAILURE; |
| } |
| |
| if ( h > 0 ) |
| { |
| PProfile oldProfile; |
| |
| |
| FT_TRACE6(( "Ending profile %p, start = %ld, height = %ld\n", |
| ras.cProfile, ras.cProfile->start, h )); |
| |
| ras.cProfile->height = h; |
| if ( overshoot ) |
| { |
| if ( ras.cProfile->flags & Flow_Up ) |
| ras.cProfile->flags |= Overshoot_Top; |
| else |
| ras.cProfile->flags |= Overshoot_Bottom; |
| } |
| |
| oldProfile = ras.cProfile; |
| ras.cProfile = (PProfile)ras.top; |
| |
| ras.top += AlignProfileSize; |
| |
| ras.cProfile->height = 0; |
| ras.cProfile->offset = ras.top; |
| |
| oldProfile->next = ras.cProfile; |
| ras.num_Profs++; |
| } |
| |
| if ( ras.top >= ras.maxBuff ) |
| { |
| FT_TRACE1(( "overflow in End_Profile\n" )); |
| ras.error = FT_THROW( Overflow ); |
| return FAILURE; |
| } |
| |
| ras.joint = FALSE; |
| |
| return SUCCESS; |
| } |
| |
| |
| /*************************************************************************/ |
| /* */ |
| /* <Function> */ |
| /* Insert_Y_Turn */ |
| /* */ |
| /* <Description> */ |
| /* Insert a salient into the sorted list placed on top of the render */ |
| /* pool. */ |
| /* */ |
| /* <Input> */ |
| /* New y scanline position. */ |
| /* */ |
| /* <Return> */ |
| /* SUCCESS on success. FAILURE in case of overflow. */ |
| /* */ |
| static Bool |
| Insert_Y_Turn( RAS_ARGS Int y ) |
| { |
| PLong y_turns; |
| Int n; |
| |
| |
| n = ras.numTurns - 1; |
| y_turns = ras.sizeBuff - ras.numTurns; |
| |
| /* look for first y value that is <= */ |
| while ( n >= 0 && y < y_turns[n] ) |
| n--; |
| |
| /* if it is <, simply insert it, ignore if == */ |
| if ( n >= 0 && y > y_turns[n] ) |
| while ( n >= 0 ) |
| { |
| Int y2 = (Int)y_turns[n]; |
| |
| |
| y_turns[n] = y; |
| y = y2; |
| n--; |
| } |
| |
| if ( n < 0 ) |
| { |
| ras.maxBuff--; |
| if ( ras.maxBuff <= ras.top ) |
| { |
| ras.error = FT_THROW( Overflow ); |
| return FAILURE; |
| } |
| ras.numTurns++; |
| ras.sizeBuff[-ras.numTurns] = y; |
| } |
| |
| return SUCCESS; |
| } |
| |
| |
| /*************************************************************************/ |
| /* */ |
| /* <Function> */ |
| /* Finalize_Profile_Table */ |
| /* */ |
| /* <Description> */ |
| /* Adjust all links in the profiles list. */ |
| /* */ |
| /* <Return> */ |
| /* SUCCESS on success. FAILURE in case of overflow. */ |
| /* */ |
| static Bool |
| Finalize_Profile_Table( RAS_ARG ) |
| { |
| UShort n; |
| PProfile p; |
| |
| |
| n = ras.num_Profs; |
| p = ras.fProfile; |
| |
| if ( n > 1 && p ) |
| { |
| while ( n > 0 ) |
| { |
| Int bottom, top; |
| |
| |
| if ( n > 1 ) |
| p->link = (PProfile)( p->offset + p->height ); |
| else |
| p->link = NULL; |
| |
| if ( p->flags & Flow_Up ) |
| { |
| bottom = (Int)p->start; |
| top = (Int)( p->start + p->height - 1 ); |
| } |
| else |
| { |
| bottom = (Int)( p->start - p->height + 1 ); |
| top = (Int)p->start; |
| p->start = bottom; |
| p->offset += p->height - 1; |
| } |
| |
| if ( Insert_Y_Turn( RAS_VARS bottom ) || |
| Insert_Y_Turn( RAS_VARS top + 1 ) ) |
| return FAILURE; |
| |
| p = p->link; |
| n--; |
| } |
| } |
| else |
| ras.fProfile = NULL; |
| |
| return SUCCESS; |
| } |
| |
| |
| /*************************************************************************/ |
| /* */ |
| /* <Function> */ |
| /* Split_Conic */ |
| /* */ |
| /* <Description> */ |
| /* Subdivide one conic Bezier into two joint sub-arcs in the Bezier */ |
| /* stack. */ |
| /* */ |
| /* <Input> */ |
| /* None (subdivided Bezier is taken from the top of the stack). */ |
| /* */ |
| /* <Note> */ |
| /* This routine is the `beef' of this component. It is _the_ inner */ |
| /* loop that should be optimized to hell to get the best performance. */ |
| /* */ |
| static void |
| Split_Conic( TPoint* base ) |
| { |
| Long 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; |
| |
| /* hand optimized. gcc doesn't seem to be too good at common */ |
| /* expression substitution and instruction scheduling ;-) */ |
| } |
| |
| |
| /*************************************************************************/ |
| /* */ |
| /* <Function> */ |
| /* Split_Cubic */ |
| /* */ |
| /* <Description> */ |
| /* Subdivide a third-order Bezier arc into two joint sub-arcs in the */ |
| /* Bezier stack. */ |
| /* */ |
| /* <Note> */ |
| /* This routine is the `beef' of the component. It is one of _the_ */ |
| /* inner loops that should be optimized like hell to get the best */ |
| /* performance. */ |
| /* */ |
| static void |
| Split_Cubic( TPoint* base ) |
| { |
| Long 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 + 1 ) >> 1; |
| base[5].x = b = ( base[3].x + d + 1 ) >> 1; |
| c = ( c + d + 1 ) >> 1; |
| base[2].x = a = ( a + c + 1 ) >> 1; |
| base[4].x = b = ( b + c + 1 ) >> 1; |
| base[3].x = ( a + b + 1 ) >> 1; |
| |
| base[6].y = base[3].y; |
| c = base[1].y; |
| d = base[2].y; |
| base[1].y = a = ( base[0].y + c + 1 ) >> 1; |
| base[5].y = b = ( base[3].y + d + 1 ) >> 1; |
| c = ( c + d + 1 ) >> 1; |
| base[2].y = a = ( a + c + 1 ) >> 1; |
| base[4].y = b = ( b + c + 1 ) >> 1; |
| base[3].y = ( a + b + 1 ) >> 1; |
| } |
| |
| |
| /*************************************************************************/ |
| /* */ |
| /* <Function> */ |
| /* Line_Up */ |
| /* */ |
| /* <Description> */ |
| /* Compute the x-coordinates of an ascending line segment and store */ |
| /* them in the render pool. */ |
| /* */ |
| /* <Input> */ |
| /* x1 :: The x-coordinate of the segment's start point. */ |
| /* */ |
| /* y1 :: The y-coordinate of the segment's start point. */ |
| /* */ |
| /* x2 :: The x-coordinate of the segment's end point. */ |
| /* */ |
| /* y2 :: The y-coordinate of the segment's end point. */ |
| /* */ |
| /* miny :: A lower vertical clipping bound value. */ |
| /* */ |
| /* maxy :: An upper vertical clipping bound value. */ |
| /* */ |
| /* <Return> */ |
| /* SUCCESS on success, FAILURE on render pool overflow. */ |
| /* */ |
| static Bool |
| Line_Up( RAS_ARGS Long x1, |
| Long y1, |
| Long x2, |
| Long y2, |
| Long miny, |
| Long maxy ) |
| { |
| Long Dx, Dy; |
| Int e1, e2, f1, f2, size; /* XXX: is `Short' sufficient? */ |
| Long Ix, Rx, Ax; |
| |
| PLong top; |
| |
| |
| Dx = x2 - x1; |
| Dy = y2 - y1; |
| |
| if ( Dy <= 0 || y2 < miny || y1 > maxy ) |
| return SUCCESS; |
| |
| if ( y1 < miny ) |
| { |
| /* Take care: miny-y1 can be a very large value; we use */ |
| /* a slow MulDiv function to avoid clipping bugs */ |
| x1 += SMulDiv( Dx, miny - y1, Dy ); |
| e1 = (Int)TRUNC( miny ); |
| f1 = 0; |
| } |
| else |
| { |
| e1 = (Int)TRUNC( y1 ); |
| f1 = (Int)FRAC( y1 ); |
| } |
| |
| if ( y2 > maxy ) |
| { |
| /* x2 += FMulDiv( Dx, maxy - y2, Dy ); UNNECESSARY */ |
| e2 = (Int)TRUNC( maxy ); |
| f2 = 0; |
| } |
| else |
| { |
| e2 = (Int)TRUNC( y2 ); |
| f2 = (Int)FRAC( y2 ); |
| } |
| |
| if ( f1 > 0 ) |
| { |
| if ( e1 == e2 ) |
| return SUCCESS; |
| else |
| { |
| x1 += SMulDiv( Dx, ras.precision - f1, Dy ); |
| e1 += 1; |
| } |
| } |
| else |
| if ( ras.joint ) |
| { |
| ras.top--; |
| ras.joint = FALSE; |
| } |
| |
| ras.joint = (char)( f2 == 0 ); |
| |
| if ( ras.fresh ) |
| { |
| ras.cProfile->start = e1; |
| ras.fresh = FALSE; |
| } |
| |
| size = e2 - e1 + 1; |
| if ( ras.top + size >= ras.maxBuff ) |
| { |
| ras.error = FT_THROW( Overflow ); |
| return FAILURE; |
| } |
| |
| if ( Dx > 0 ) |
| { |
| Ix = SMulDiv_No_Round( ras.precision, Dx, Dy ); |
| Rx = ( ras.precision * Dx ) % Dy; |
| Dx = 1; |
| } |
| else |
| { |
| Ix = -SMulDiv_No_Round( ras.precision, -Dx, Dy ); |
| Rx = ( ras.precision * -Dx ) % Dy; |
| Dx = -1; |
| } |
| |
| Ax = -Dy; |
| top = ras.top; |
| |
| while ( size > 0 ) |
| { |
| *top++ = x1; |
| |
| x1 += Ix; |
| Ax += Rx; |
| if ( Ax >= 0 ) |
| { |
| Ax -= Dy; |
| x1 += Dx; |
| } |
| size--; |
| } |
| |
| ras.top = top; |
| return SUCCESS; |
| } |
| |
| |
| /*************************************************************************/ |
| /* */ |
| /* <Function> */ |
| /* Line_Down */ |
| /* */ |
| /* <Description> */ |
| /* Compute the x-coordinates of an descending line segment and store */ |
| /* them in the render pool. */ |
| /* */ |
| /* <Input> */ |
| /* x1 :: The x-coordinate of the segment's start point. */ |
| /* */ |
| /* y1 :: The y-coordinate of the segment's start point. */ |
| /* */ |
| /* x2 :: The x-coordinate of the segment's end point. */ |
| /* */ |
| /* y2 :: The y-coordinate of the segment's end point. */ |
| /* */ |
| /* miny :: A lower vertical clipping bound value. */ |
| /* */ |
| /* maxy :: An upper vertical clipping bound value. */ |
| /* */ |
| /* <Return> */ |
| /* SUCCESS on success, FAILURE on render pool overflow. */ |
| /* */ |
| static Bool |
| Line_Down( RAS_ARGS Long x1, |
| Long y1, |
| Long x2, |
| Long y2, |
| Long miny, |
| Long maxy ) |
| { |
| Bool result, fresh; |
| |
| |
| fresh = ras.fresh; |
| |
| result = Line_Up( RAS_VARS x1, -y1, x2, -y2, -maxy, -miny ); |
| |
| if ( fresh && !ras.fresh ) |
| ras.cProfile->start = -ras.cProfile->start; |
| |
| return result; |
| } |
| |
| |
| /* A function type describing the functions used to split Bezier arcs */ |
| typedef void (*TSplitter)( TPoint* base ); |
| |
| |
| /*************************************************************************/ |
| /* */ |
| /* <Function> */ |
| /* Bezier_Up */ |
| /* */ |
| /* <Description> */ |
| /* Compute the x-coordinates of an ascending Bezier arc and store */ |
| /* them in the render pool. */ |
| /* */ |
| /* <Input> */ |
| /* degree :: The degree of the Bezier arc (either 2 or 3). */ |
| /* */ |
| /* splitter :: The function to split Bezier arcs. */ |
| /* */ |
| /* miny :: A lower vertical clipping bound value. */ |
| /* */ |
| /* maxy :: An upper vertical clipping bound value. */ |
| /* */ |
| /* <Return> */ |
| /* SUCCESS on success, FAILURE on render pool overflow. */ |
| /* */ |
| static Bool |
| Bezier_Up( RAS_ARGS Int degree, |
| TSplitter splitter, |
| Long miny, |
| Long maxy ) |
| { |
| Long y1, y2, e, e2, e0; |
| Short f1; |
| |
| TPoint* arc; |
| TPoint* start_arc; |
| |
| PLong top; |
| |
| |
| arc = ras.arc; |
| y1 = arc[degree].y; |
| y2 = arc[0].y; |
| top = ras.top; |
| |
| if ( y2 < miny || y1 > maxy ) |
| goto Fin; |
| |
| e2 = FLOOR( y2 ); |
| |
| if ( e2 > maxy ) |
| e2 = maxy; |
| |
| e0 = miny; |
| |
| if ( y1 < miny ) |
| e = miny; |
| else |
| { |
| e = CEILING( y1 ); |
| f1 = (Short)( FRAC( y1 ) ); |
| e0 = e; |
| |
| if ( f1 == 0 ) |
| { |
| if ( ras.joint ) |
| { |
| top--; |
| ras.joint = FALSE; |
| } |
| |
| *top++ = arc[degree].x; |
| |
| e += ras.precision; |
| } |
| } |
| |
| if ( ras.fresh ) |
| { |
| ras.cProfile->start = TRUNC( e0 ); |
| ras.fresh = FALSE; |
| } |
| |
| if ( e2 < e ) |
| goto Fin; |
| |
| if ( ( top + TRUNC( e2 - e ) + 1 ) >= ras.maxBuff ) |
| { |
| ras.top = top; |
| ras.error = FT_THROW( Overflow ); |
| return FAILURE; |
| } |
| |
| start_arc = arc; |
| |
| while ( arc >= start_arc && e <= e2 ) |
| { |
| ras.joint = FALSE; |
| |
| y2 = arc[0].y; |
| |
| if ( y2 > e ) |
| { |
| y1 = arc[degree].y; |
| if ( y2 - y1 >= ras.precision_step ) |
| { |
| splitter( arc ); |
| arc += degree; |
| } |
| else |
| { |
| *top++ = arc[degree].x + FMulDiv( arc[0].x - arc[degree].x, |
| e - y1, y2 - y1 ); |
| arc -= degree; |
| e += ras.precision; |
| } |
| } |
| else |
| { |
| if ( y2 == e ) |
| { |
| ras.joint = TRUE; |
| *top++ = arc[0].x; |
| |
| e += ras.precision; |
| } |
| arc -= degree; |
| } |
| } |
| |
| Fin: |
| ras.top = top; |
| ras.arc -= degree; |
| return SUCCESS; |
| } |
| |
| |
| /*************************************************************************/ |
| /* */ |
| /* <Function> */ |
| /* Bezier_Down */ |
| /* */ |
| /* <Description> */ |
| /* Compute the x-coordinates of an descending Bezier arc and store */ |
| /* them in the render pool. */ |
| /* */ |
| /* <Input> */ |
| /* degree :: The degree of the Bezier arc (either 2 or 3). */ |
| /* */ |
| /* splitter :: The function to split Bezier arcs. */ |
| /* */ |
| /* miny :: A lower vertical clipping bound value. */ |
| /* */ |
| /* maxy :: An upper vertical clipping bound value. */ |
| /* */ |
| /* <Return> */ |
| /* SUCCESS on success, FAILURE on render pool overflow. */ |
| /* */ |
| static Bool |
| Bezier_Down( RAS_ARGS Int degree, |
| TSplitter splitter, |
| Long miny, |
| Long maxy ) |
| { |
| TPoint* arc = ras.arc; |
| Bool result, fresh; |
| |
| |
| arc[0].y = -arc[0].y; |
| arc[1].y = -arc[1].y; |
| arc[2].y = -arc[2].y; |
| if ( degree > 2 ) |
| arc[3].y = -arc[3].y; |
| |
| fresh = ras.fresh; |
| |
| result = Bezier_Up( RAS_VARS degree, splitter, -maxy, -miny ); |
| |
| if ( fresh && !ras.fresh ) |
| ras.cProfile->start = -ras.cProfile->start; |
| |
| arc[0].y = -arc[0].y; |
| return result; |
| } |
| |
| |
| /*************************************************************************/ |
| /* */ |
| /* <Function> */ |
| /* Line_To */ |
| /* */ |
| /* <Description> */ |
| /* Inject a new line segment and adjust the Profiles list. */ |
| /* */ |
| /* <Input> */ |
| /* x :: The x-coordinate of the segment's end point (its start point */ |
| /* is stored in `lastX'). */ |
| /* */ |
| /* y :: The y-coordinate of the segment's end point (its start point */ |
| /* is stored in `lastY'). */ |
| /* */ |
| /* <Return> */ |
| /* SUCCESS on success, FAILURE on render pool overflow or incorrect */ |
| /* profile. */ |
| /* */ |
| static Bool |
| Line_To( RAS_ARGS Long x, |
| Long y ) |
| { |
| /* First, detect a change of direction */ |
| |
| switch ( ras.state ) |
| { |
| case Unknown_State: |
| if ( y > ras.lastY ) |
| { |
| if ( New_Profile( RAS_VARS Ascending_State, |
| IS_BOTTOM_OVERSHOOT( ras.lastY ) ) ) |
| return FAILURE; |
| } |
| else |
| { |
| if ( y < ras.lastY ) |
| if ( New_Profile( RAS_VARS Descending_State, |
| IS_TOP_OVERSHOOT( ras.lastY ) ) ) |
| return FAILURE; |
| } |
| break; |
| |
| case Ascending_State: |
| if ( y < ras.lastY ) |
| { |
| if ( End_Profile( RAS_VARS IS_TOP_OVERSHOOT( ras.lastY ) ) || |
| New_Profile( RAS_VARS Descending_State, |
| IS_TOP_OVERSHOOT( ras.lastY ) ) ) |
| return FAILURE; |
| } |
| break; |
| |
| case Descending_State: |
| if ( y > ras.lastY ) |
| { |
| if ( End_Profile( RAS_VARS IS_BOTTOM_OVERSHOOT( ras.lastY ) ) || |
| New_Profile( RAS_VARS Ascending_State, |
| IS_BOTTOM_OVERSHOOT( ras.lastY ) ) ) |
| return FAILURE; |
| } |
| break; |
| |
| default: |
| ; |
| } |
| |
| /* Then compute the lines */ |
| |
| switch ( ras.state ) |
| { |
| case Ascending_State: |
| if ( Line_Up( RAS_VARS ras.lastX, ras.lastY, |
| x, y, ras.minY, ras.maxY ) ) |
| return FAILURE; |
| break; |
| |
| case Descending_State: |
| if ( Line_Down( RAS_VARS ras.lastX, ras.lastY, |
| x, y, ras.minY, ras.maxY ) ) |
| return FAILURE; |
| break; |
| |
| default: |
| ; |
| } |
| |
| ras.lastX = x; |
| ras.lastY = y; |
| |
| return SUCCESS; |
| } |
| |
| |
| /*************************************************************************/ |
| /* */ |
| /* <Function> */ |
| /* Conic_To */ |
| /* */ |
| /* <Description> */ |
| /* Inject a new conic arc and adjust the profile list. */ |
| /* */ |
| /* <Input> */ |
| /* cx :: The x-coordinate of the arc's new control point. */ |
| /* */ |
| /* cy :: The y-coordinate of the arc's new control point. */ |
| /* */ |
| /* x :: The x-coordinate of the arc's end point (its start point is */ |
| /* stored in `lastX'). */ |
| /* */ |
| /* y :: The y-coordinate of the arc's end point (its start point is */ |
| /* stored in `lastY'). */ |
| /* */ |
| /* <Return> */ |
| /* SUCCESS on success, FAILURE on render pool overflow or incorrect */ |
| /* profile. */ |
| /* */ |
| static Bool |
| Conic_To( RAS_ARGS Long cx, |
| Long cy, |
| Long x, |
| Long y ) |
| { |
| Long y1, y2, y3, x3, ymin, ymax; |
| TStates state_bez; |
| |
| |
| ras.arc = ras.arcs; |
| ras.arc[2].x = ras.lastX; |
| ras.arc[2].y = ras.lastY; |
| ras.arc[1].x = cx; |
| ras.arc[1].y = cy; |
| ras.arc[0].x = x; |
| ras.arc[0].y = y; |
| |
| do |
| { |
| y1 = ras.arc[2].y; |
| y2 = ras.arc[1].y; |
| y3 = ras.arc[0].y; |
| x3 = ras.arc[0].x; |
| |
| /* first, categorize the Bezier arc */ |
| |
| if ( y1 <= y3 ) |
| { |
| ymin = y1; |
| ymax = y3; |
| } |
| else |
| { |
| ymin = y3; |
| ymax = y1; |
| } |
| |
| if ( y2 < ymin || y2 > ymax ) |
| { |
| /* this arc has no given direction, split it! */ |
| Split_Conic( ras.arc ); |
| ras.arc += 2; |
| } |
| else if ( y1 == y3 ) |
| { |
| /* this arc is flat, ignore it and pop it from the Bezier stack */ |
| ras.arc -= 2; |
| } |
| else |
| { |
| /* the arc is y-monotonous, either ascending or descending */ |
| /* detect a change of direction */ |
| state_bez = y1 < y3 ? Ascending_State : Descending_State; |
| if ( ras.state != state_bez ) |
| { |
| Bool o = state_bez == Ascending_State ? IS_BOTTOM_OVERSHOOT( y1 ) |
| : IS_TOP_OVERSHOOT( y1 ); |
| |
| |
| /* finalize current profile if any */ |
| if ( ras.state != Unknown_State && |
| End_Profile( RAS_VARS o ) ) |
| goto Fail; |
| |
| /* create a new profile */ |
| if ( New_Profile( RAS_VARS state_bez, o ) ) |
| goto Fail; |
| } |
| |
| /* now call the appropriate routine */ |
| if ( state_bez == Ascending_State ) |
| { |
| if ( Bezier_Up( RAS_VARS 2, Split_Conic, ras.minY, ras.maxY ) ) |
| goto Fail; |
| } |
| else |
| if ( Bezier_Down( RAS_VARS 2, Split_Conic, ras.minY, ras.maxY ) ) |
| goto Fail; |
| } |
| |
| } while ( ras.arc >= ras.arcs ); |
| |
| ras.lastX = x3; |
| ras.lastY = y3; |
| |
| return SUCCESS; |
| |
| Fail: |
| return FAILURE; |
| } |
| |
| |
| /*************************************************************************/ |
| /* */ |
| /* <Function> */ |
| /* Cubic_To */ |
| /* */ |
| /* <Description> */ |
| /* Inject a new cubic arc and adjust the profile list. */ |
| /* */ |
| /* <Input> */ |
| /* cx1 :: The x-coordinate of the arc's first new control point. */ |
| /* */ |
| /* cy1 :: The y-coordinate of the arc's first new control point. */ |
| /* */ |
| /* cx2 :: The x-coordinate of the arc's second new control point. */ |
| /* */ |
| /* cy2 :: The y-coordinate of the arc's second new control point. */ |
| /* */ |
| /* x :: The x-coordinate of the arc's end point (its start point is */ |
| /* stored in `lastX'). */ |
| /* */ |
| /* y :: The y-coordinate of the arc's end point (its start point is */ |
| /* stored in `lastY'). */ |
| /* */ |
| /* <Return> */ |
| /* SUCCESS on success, FAILURE on render pool overflow or incorrect */ |
| /* profile. */ |
| /* */ |
| static Bool |
| Cubic_To( RAS_ARGS Long cx1, |
| Long cy1, |
| Long cx2, |
| Long cy2, |
| Long x, |
| Long y ) |
| { |
| Long y1, y2, y3, y4, x4, ymin1, ymax1, ymin2, ymax2; |
| TStates state_bez; |
| |
| |
| ras.arc = ras.arcs; |
| ras.arc[3].x = ras.lastX; |
| ras.arc[3].y = ras.lastY; |
| ras.arc[2].x = cx1; |
| ras.arc[2].y = cy1; |
| ras.arc[1].x = cx2; |
| ras.arc[1].y = cy2; |
| ras.arc[0].x = x; |
| ras.arc[0].y = y; |
| |
| do |
| { |
| y1 = ras.arc[3].y; |
| y2 = ras.arc[2].y; |
| y3 = ras.arc[1].y; |
| y4 = ras.arc[0].y; |
| x4 = ras.arc[0].x; |
| |
| /* first, categorize the Bezier arc */ |
| |
| if ( y1 <= y4 ) |
| { |
| ymin1 = y1; |
| ymax1 = y4; |
| } |
| else |
| { |
| ymin1 = y4; |
| ymax1 = y1; |
| } |
| |
| if ( y2 <= y3 ) |
| { |
| ymin2 = y2; |
| ymax2 = y3; |
| } |
| else |
| { |
| ymin2 = y3; |
| ymax2 = y2; |
| } |
| |
| if ( ymin2 < ymin1 || ymax2 > ymax1 ) |
| { |
| /* this arc has no given direction, split it! */ |
| Split_Cubic( ras.arc ); |
| ras.arc += 3; |
| } |
| else if ( y1 == y4 ) |
| { |
| /* this arc is flat, ignore it and pop it from the Bezier stack */ |
| ras.arc -= 3; |
| } |
| else |
| { |
| state_bez = ( y1 <= y4 ) ? Ascending_State : Descending_State; |
| |
| /* detect a change of direction */ |
| if ( ras.state != state_bez ) |
| { |
| Bool o = state_bez == Ascending_State ? IS_BOTTOM_OVERSHOOT( y1 ) |
| : IS_TOP_OVERSHOOT( y1 ); |
| |
| |
| /* finalize current profile if any */ |
| if ( ras.state != Unknown_State && |
| End_Profile( RAS_VARS o ) ) |
| goto Fail; |
| |
| if ( New_Profile( RAS_VARS state_bez, o ) ) |
| goto Fail; |
| } |
| |
| /* compute intersections */ |
| if ( state_bez == Ascending_State ) |
| { |
| if ( Bezier_Up( RAS_VARS 3, Split_Cubic, ras.minY, ras.maxY ) ) |
| goto Fail; |
| } |
| else |
| if ( Bezier_Down( RAS_VARS 3, Split_Cubic, ras.minY, ras.maxY ) ) |
| goto Fail; |
| } |
| |
| } while ( ras.arc >= ras.arcs ); |
| |
| ras.lastX = x4; |
| ras.lastY = y4; |
| |
| return SUCCESS; |
| |
| Fail: |
| return FAILURE; |
| } |
| |
| |
| #undef SWAP_ |
| #define SWAP_( x, y ) do \ |
| { \ |
| Long swap = x; \ |
| \ |
| \ |
| x = y; \ |
| y = swap; \ |
| } while ( 0 ) |
| |
| |
| /*************************************************************************/ |
| /* */ |
| /* <Function> */ |
| /* Decompose_Curve */ |
| /* */ |
| /* <Description> */ |
| /* Scan the outline arrays in order to emit individual segments and */ |
| /* Beziers by calling Line_To() and Bezier_To(). It handles all */ |
| /* weird cases, like when the first point is off the curve, or when */ |
| /* there are simply no `on' points in the contour! */ |
| /* */ |
| /* <Input> */ |
| /* first :: The index of the first point in the contour. */ |
| /* */ |
| /* last :: The index of the last point in the contour. */ |
| /* */ |
| /* flipped :: If set, flip the direction of the curve. */ |
| /* */ |
| /* <Return> */ |
| /* SUCCESS on success, FAILURE on error. */ |
| /* */ |
| static Bool |
| Decompose_Curve( RAS_ARGS UShort first, |
| UShort last, |
| int flipped ) |
| { |
| FT_Vector v_last; |
| FT_Vector v_control; |
| FT_Vector v_start; |
| |
| FT_Vector* points; |
| FT_Vector* point; |
| FT_Vector* limit; |
| char* tags; |
| |
| unsigned tag; /* current point's state */ |
| |
| |
| points = ras.outline.points; |
| limit = points + last; |
| |
| v_start.x = SCALED( points[first].x ); |
| v_start.y = SCALED( points[first].y ); |
| v_last.x = SCALED( points[last].x ); |
| v_last.y = SCALED( points[last].y ); |
| |
| if ( flipped ) |
| { |
| SWAP_( v_start.x, v_start.y ); |
| SWAP_( v_last.x, v_last.y ); |
| } |
| |
| v_control = v_start; |
| |
| point = points + first; |
| tags = ras.outline.tags + first; |
| |
| /* set scan mode if necessary */ |
| if ( tags[0] & FT_CURVE_TAG_HAS_SCANMODE ) |
| ras.dropOutControl = (Byte)tags[0] >> 5; |
| |
| 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( ras.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--; |
| } |
| |
| ras.lastX = v_start.x; |
| ras.lastY = v_start.y; |
| |
| while ( point < limit ) |
| { |
| point++; |
| tags++; |
| |
| tag = FT_CURVE_TAG( tags[0] ); |
| |
| switch ( tag ) |
| { |
| case FT_CURVE_TAG_ON: /* emit a single line_to */ |
| { |
| Long x, y; |
| |
| |
| x = SCALED( point->x ); |
| y = SCALED( point->y ); |
| if ( flipped ) |
| SWAP_( x, y ); |
| |
| if ( Line_To( RAS_VARS x, y ) ) |
| goto Fail; |
| continue; |
| } |
| |
| case FT_CURVE_TAG_CONIC: /* consume conic arcs */ |
| v_control.x = SCALED( point[0].x ); |
| v_control.y = SCALED( point[0].y ); |
| |
| if ( flipped ) |
| SWAP_( v_control.x, v_control.y ); |
| |
| Do_Conic: |
| if ( point < limit ) |
| { |
| FT_Vector v_middle; |
| Long x, y; |
| |
| |
| point++; |
| tags++; |
| tag = FT_CURVE_TAG( tags[0] ); |
| |
| x = SCALED( point[0].x ); |
| y = SCALED( point[0].y ); |
| |
| if ( flipped ) |
| SWAP_( x, y ); |
| |
| if ( tag == FT_CURVE_TAG_ON ) |
| { |
| if ( Conic_To( RAS_VARS v_control.x, v_control.y, x, y ) ) |
| goto Fail; |
| continue; |
| } |
| |
| if ( tag != FT_CURVE_TAG_CONIC ) |
| goto Invalid_Outline; |
| |
| v_middle.x = ( v_control.x + x ) / 2; |
| v_middle.y = ( v_control.y + y ) / 2; |
| |
| if ( Conic_To( RAS_VARS v_control.x, v_control.y, |
| v_middle.x, v_middle.y ) ) |
| goto Fail; |
| |
| v_control.x = x; |
| v_control.y = y; |
| |
| goto Do_Conic; |
| } |
| |
| if ( Conic_To( RAS_VARS v_control.x, v_control.y, |
| v_start.x, v_start.y ) ) |
| goto Fail; |
| |
| goto Close; |
| |
| default: /* FT_CURVE_TAG_CUBIC */ |
| { |
| Long x1, y1, x2, y2, x3, y3; |
| |
| |
| if ( point + 1 > limit || |
| FT_CURVE_TAG( tags[1] ) != FT_CURVE_TAG_CUBIC ) |
| goto Invalid_Outline; |
| |
| point += 2; |
| tags += 2; |
| |
| x1 = SCALED( point[-2].x ); |
| y1 = SCALED( point[-2].y ); |
| x2 = SCALED( point[-1].x ); |
| y2 = SCALED( point[-1].y ); |
| |
| if ( flipped ) |
| { |
| SWAP_( x1, y1 ); |
| SWAP_( x2, y2 ); |
| } |
| |
| if ( point <= limit ) |
| { |
| x3 = SCALED( point[0].x ); |
| y3 = SCALED( point[0].y ); |
| |
| if ( flipped ) |
| SWAP_( x3, y3 ); |
| |
| if ( Cubic_To( RAS_VARS x1, y1, x2, y2, x3, y3 ) ) |
| goto Fail; |
| continue; |
| } |
| |
| if ( Cubic_To( RAS_VARS x1, y1, x2, y2, v_start.x, v_start.y ) ) |
| goto Fail; |
| goto Close; |
| } |
| } |
| } |
| |
| /* close the contour with a line segment */ |
| if ( Line_To( RAS_VARS v_start.x, v_start.y ) ) |
| goto Fail; |
| |
| Close: |
| return SUCCESS; |
| |
| Invalid_Outline: |
| ras.error = FT_THROW( Invalid ); |
| |
| Fail: |
| return FAILURE; |
| } |
| |
| |
| /*************************************************************************/ |
| /* */ |
| /* <Function> */ |
| /* Convert_Glyph */ |
| /* */ |
| /* <Description> */ |
| /* Convert a glyph into a series of segments and arcs and make a */ |
| /* profiles list with them. */ |
| /* */ |
| /* <Input> */ |
| /* flipped :: If set, flip the direction of curve. */ |
| /* */ |
| /* <Return> */ |
| /* SUCCESS on success, FAILURE if any error was encountered during */ |
| /* rendering. */ |
| /* */ |
| static Bool |
| Convert_Glyph( RAS_ARGS int flipped ) |
| { |
| int i; |
| unsigned start; |
| |
| |
| ras.fProfile = NULL; |
| ras.joint = FALSE; |
| ras.fresh = FALSE; |
| |
| ras.maxBuff = ras.sizeBuff - AlignProfileSize; |
| |
| ras.numTurns = 0; |
| |
| ras.cProfile = (PProfile)ras.top; |
| ras.cProfile->offset = ras.top; |
| ras.num_Profs = 0; |
| |
| start = 0; |
| |
| for ( i = 0; i < ras.outline.n_contours; i++ ) |
| { |
| PProfile lastProfile; |
| Bool o; |
| |
| |
| ras.state = Unknown_State; |
| ras.gProfile = NULL; |
| |
| if ( Decompose_Curve( RAS_VARS (unsigned short)start, |
| ras.outline.contours[i], |
| flipped ) ) |
| return FAILURE; |
| |
| start = ras.outline.contours[i] + 1; |
| |
| /* we must now check whether the extreme arcs join or not */ |
| if ( FRAC( ras.lastY ) == 0 && |
| ras.lastY >= ras.minY && |
| ras.lastY <= ras.maxY ) |
| if ( ras.gProfile && |
| ( ras.gProfile->flags & Flow_Up ) == |
| ( ras.cProfile->flags & Flow_Up ) ) |
| ras.top--; |
| /* Note that ras.gProfile can be nil if the contour was too small */ |
| /* to be drawn. */ |
| |
| lastProfile = ras.cProfile; |
| if ( ras.cProfile->flags & Flow_Up ) |
| o = IS_TOP_OVERSHOOT( ras.lastY ); |
| else |
| o = IS_BOTTOM_OVERSHOOT( ras.lastY ); |
| if ( End_Profile( RAS_VARS o ) ) |
| return FAILURE; |
| |
| /* close the `next profile in contour' linked list */ |
| if ( ras.gProfile ) |
| lastProfile->next = ras.gProfile; |
| } |
| |
| if ( Finalize_Profile_Table( RAS_VAR ) ) |
| return FAILURE; |
| |
| return (Bool)( ras.top < ras.maxBuff ? SUCCESS : FAILURE ); |
| } |
| |
| |
| /*************************************************************************/ |
| /*************************************************************************/ |
| /** **/ |
| /** SCAN-LINE SWEEPS AND DRAWING **/ |
| /** **/ |
| /*************************************************************************/ |
| /*************************************************************************/ |
| |
| |
| /*************************************************************************/ |
| /* */ |
| /* Init_Linked */ |
| /* */ |
| /* Initializes an empty linked list. */ |
| /* */ |
| static void |
| Init_Linked( TProfileList* l ) |
| { |
| *l = NULL; |
| } |
| |
| |
| /*************************************************************************/ |
| /* */ |
| /* InsNew */ |
| /* */ |
| /* Inserts a new profile in a linked list. */ |
| /* */ |
| static void |
| InsNew( PProfileList list, |
| PProfile profile ) |
| { |
| PProfile *old, current; |
| Long x; |
| |
| |
| old = list; |
| current = *old; |
| x = profile->X; |
| |
| while ( current ) |
| { |
| if ( x < current->X ) |
| break; |
| old = ¤t->link; |
| current = *old; |
| } |
| |
| profile->link = current; |
| *old = profile; |
| } |
| |
| |
| /*************************************************************************/ |
| /* */ |
| /* DelOld */ |
| /* */ |
| /* Removes an old profile from a linked list. */ |
| /* */ |
| static void |
| DelOld( PProfileList list, |
| PProfile profile ) |
| { |
| PProfile *old, current; |
| |
| |
| old = list; |
| current = *old; |
| |
| while ( current ) |
| { |
| if ( current == profile ) |
| { |
| *old = current->link; |
| return; |
| } |
| |
| old = ¤t->link; |
| current = *old; |
| } |
| |
| /* we should never get there, unless the profile was not part of */ |
| /* the list. */ |
| } |
| |
| |
| /*************************************************************************/ |
| /* */ |
| /* Sort */ |
| /* */ |
| /* Sorts a trace list. In 95%, the list is already sorted. We need */ |
| /* an algorithm which is fast in this case. Bubble sort is enough */ |
| /* and simple. */ |
| /* */ |
| static void |
| Sort( PProfileList list ) |
| { |
| PProfile *old, current, next; |
| |
| |
| /* First, set the new X coordinate of each profile */ |
| current = *list; |
| while ( current ) |
| { |
| current->X = *current->offset; |
| current->offset += current->flags & Flow_Up ? 1 : -1; |
| current->height--; |
| current = current->link; |
| } |
| |
| /* Then sort them */ |
| old = list; |
| current = *old; |
| |
| if ( !current ) |
| return; |
| |
| next = current->link; |
| |
| while ( next ) |
| { |
| if ( current->X <= next->X ) |
| { |
| old = ¤t->link; |
| current = *old; |
| |
| if ( !current ) |
| return; |
| } |
| else |
| { |
| *old = next; |
| current->link = next->link; |
| next->link = current; |
| |
| old = list; |
| current = *old; |
| } |
| |
| next = current->link; |
| } |
| } |
| |
| |
| /*************************************************************************/ |
| /* */ |
| /* Vertical Sweep Procedure Set */ |
| /* */ |
| /* These four routines are used during the vertical black/white sweep */ |
| /* phase by the generic Draw_Sweep() function. */ |
| /* */ |
| /*************************************************************************/ |
| |
| static void |
| Vertical_Sweep_Init( RAS_ARGS Short* min, |
| Short* max ) |
| { |
| Long pitch = ras.target.pitch; |
| |
| FT_UNUSED( max ); |
| |
| |
| ras.traceIncr = (Short)-pitch; |
| ras.traceOfs = -*min * pitch; |
| if ( pitch > 0 ) |
| ras.traceOfs += ( ras.target.rows - 1 ) * pitch; |
| |
| ras.gray_min_x = 0; |
| ras.gray_max_x = 0; |
| } |
| |
| |
| static void |
| Vertical_Sweep_Span( RAS_ARGS Short y, |
| FT_F26Dot6 x1, |
| FT_F26Dot6 x2, |
| PProfile left, |
| PProfile right ) |
| { |
| Long e1, e2; |
| Byte* target; |
| |
| FT_UNUSED( y ); |
| FT_UNUSED( left ); |
| FT_UNUSED( right ); |
| |
| |
| /* Drop-out control */ |
| |
| e1 = TRUNC( CEILING( x1 ) ); |
| |
| if ( x2 - x1 - ras.precision <= ras.precision_jitter ) |
| e2 = e1; |
| else |
| e2 = TRUNC( FLOOR( x2 ) ); |
| |
| if ( e2 >= 0 && e1 < ras.bWidth ) |
| { |
| int c1, c2; |
| Byte f1, f2; |
| |
| |
| if ( e1 < 0 ) |
| e1 = 0; |
| if ( e2 >= ras.bWidth ) |
| e2 = ras.bWidth - 1; |
| |
| c1 = (Short)( e1 >> 3 ); |
| c2 = (Short)( e2 >> 3 ); |
| |
| f1 = (Byte) ( 0xFF >> ( e1 & 7 ) ); |
| f2 = (Byte) ~( 0x7F >> ( e2 & 7 ) ); |
| |
| if ( ras.gray_min_x > c1 ) |
| ras.gray_min_x = (short)c1; |
| if ( ras.gray_max_x < c2 ) |
| ras.gray_max_x = (short)c2; |
| |
| target = ras.bTarget + ras.traceOfs + c1; |
| c2 -= c1; |
| |
| if ( c2 > 0 ) |
| { |
| target[0] |= f1; |
| |
| /* memset() is slower than the following code on many platforms. */ |
| /* This is due to the fact that, in the vast majority of cases, */ |
| /* the span length in bytes is relatively small. */ |
| c2--; |
| while ( c2 > 0 ) |
| { |
| *(++target) = 0xFF; |
| c2--; |
| } |
| target[1] |= f2; |
| } |
| else |
| *target |= ( f1 & f2 ); |
| } |
| } |
| |
| |
| static void |
| Vertical_Sweep_Drop( RAS_ARGS Short y, |
| FT_F26Dot6 x1, |
| FT_F26Dot6 x2, |
| PProfile left, |
| PProfile right ) |
| { |
| Long e1, e2, pxl; |
| Short c1, f1; |
| |
| |
| /* Drop-out control */ |
| |
| /* e2 x2 x1 e1 */ |
| /* */ |
| /* ^ | */ |
| /* | | */ |
| /* +-------------+---------------------+------------+ */ |
| /* | | */ |
| /* | v */ |
| /* */ |
| /* pixel contour contour pixel */ |
| /* center center */ |
| |
| /* drop-out mode scan conversion rules (as defined in OpenType) */ |
| /* --------------------------------------------------------------- */ |
| /* 0 1, 2, 3 */ |
| /* 1 1, 2, 4 */ |
| /* 2 1, 2 */ |
| /* 3 same as mode 2 */ |
| /* 4 1, 2, 5 */ |
| /* 5 1, 2, 6 */ |
| /* 6, 7 same as mode 2 */ |
| |
| e1 = CEILING( x1 ); |
| e2 = FLOOR ( x2 ); |
| pxl = e1; |
| |
| if ( e1 > e2 ) |
| { |
| Int dropOutControl = left->flags & 7; |
| |
| |
| if ( e1 == e2 + ras.precision ) |
| { |
| switch ( dropOutControl ) |
| { |
| case 0: /* simple drop-outs including stubs */ |
| pxl = e2; |
| break; |
| |
| case 4: /* smart drop-outs including stubs */ |
| pxl = FLOOR( ( x1 + x2 - 1 ) / 2 + ras.precision_half ); |
| break; |
| |
| case 1: /* simple drop-outs excluding stubs */ |
| case 5: /* smart drop-outs excluding stubs */ |
| |
| /* Drop-out Control Rules #4 and #6 */ |
| |
| /* The specification neither provides an exact definition */ |
| /* of a `stub' nor gives exact rules to exclude them. */ |
| /* */ |
| /* Here the constraints we use to recognize a stub. */ |
| /* */ |
| /* upper stub: */ |
| /* */ |
| /* - P_Left and P_Right are in the same contour */ |
| /* - P_Right is the successor of P_Left in that contour */ |
| /* - y is the top of P_Left and P_Right */ |
| /* */ |
| /* lower stub: */ |
| /* */ |
| /* - P_Left and P_Right are in the same contour */ |
| /* - P_Left is the successor of P_Right in that contour */ |
| /* - y is the bottom of P_Left */ |
| /* */ |
| /* We draw a stub if the following constraints are met. */ |
| /* */ |
| /* - for an upper or lower stub, there is top or bottom */ |
| /* overshoot, respectively */ |
| /* - the covered interval is greater or equal to a half */ |
| /* pixel */ |
| |
| /* upper stub test */ |
| if ( left->next == right && |
| left->height <= 0 && |
| !( left->flags & Overshoot_Top && |
| x2 - x1 >= ras.precision_half ) ) |
| return; |
| |
| /* lower stub test */ |
| if ( right->next == left && |
| left->start == y && |
| !( left->flags & Overshoot_Bottom && |
| x2 - x1 >= ras.precision_half ) ) |
| return; |
| |
| if ( dropOutControl == 1 ) |
| pxl = e2; |
| else |
| pxl = FLOOR( ( x1 + x2 - 1 ) / 2 + ras.precision_half ); |
| break; |
| |
| default: /* modes 2, 3, 6, 7 */ |
| return; /* no drop-out control */ |
| } |
| |
| /* undocumented but confirmed: If the drop-out would result in a */ |
| /* pixel outside of the bounding box, use the pixel inside of the */ |
| /* bounding box instead */ |
| if ( pxl < 0 ) |
| pxl = e1; |
| else if ( TRUNC( pxl ) >= ras.bWidth ) |
| pxl = e2; |
| |
| /* check that the other pixel isn't set */ |
| e1 = pxl == e1 ? e2 : e1; |
| |
| e1 = TRUNC( e1 ); |
| |
| c1 = (Short)( e1 >> 3 ); |
| f1 = (Short)( e1 & 7 ); |
| |
| if ( e1 >= 0 && e1 < ras.bWidth && |
| ras.bTarget[ras.traceOfs + c1] & ( 0x80 >> f1 ) ) |
| return; |
| } |
| else |
| return; |
| } |
| |
| e1 = TRUNC( pxl ); |
| |
| if ( e1 >= 0 && e1 < ras.bWidth ) |
| { |
| c1 = (Short)( e1 >> 3 ); |
| f1 = (Short)( e1 & 7 ); |
| |
| if ( ras.gray_min_x > c1 ) |
| ras.gray_min_x = c1; |
| if ( ras.gray_max_x < c1 ) |
| ras.gray_max_x = c1; |
| |
| ras.bTarget[ras.traceOfs + c1] |= (char)( 0x80 >> f1 ); |
| } |
| } |
| |
| |
| static void |
| Vertical_Sweep_Step( RAS_ARG ) |
| { |
| ras.traceOfs += ras.traceIncr; |
| } |
| |
| |
| /***********************************************************************/ |
| /* */ |
| /* Horizontal Sweep Procedure Set */ |
| /* */ |
| /* These four routines are used during the horizontal black/white */ |
| /* sweep phase by the generic Draw_Sweep() function. */ |
| /* */ |
| /***********************************************************************/ |
| |
| static void |
| Horizontal_Sweep_Init( RAS_ARGS Short* min, |
| Short* max ) |
| { |
| /* nothing, really */ |
| FT_UNUSED_RASTER; |
| FT_UNUSED( min ); |
| FT_UNUSED( max ); |
| } |
| |
| |
| static void |
| Horizontal_Sweep_Span( RAS_ARGS Short y, |
| FT_F26Dot6 x1, |
| FT_F26Dot6 x2, |
| PProfile left, |
| PProfile right ) |
| { |
| FT_UNUSED( left ); |
| FT_UNUSED( right ); |
| |
| |
| if ( x2 - x1 < ras.precision ) |
| { |
| Long e1, e2; |
| |
| |
| e1 = CEILING( x1 ); |
| e2 = FLOOR ( x2 ); |
| |
| if ( e1 == e2 ) |
| { |
| Byte f1; |
| PByte bits; |
| |
| |
| bits = ras.bTarget + ( y >> 3 ); |
| f1 = (Byte)( 0x80 >> ( y & 7 ) ); |
| |
| e1 = TRUNC( e1 ); |
| |
| if ( e1 >= 0 && e1 < ras.target.rows ) |
| { |
| PByte p; |
| |
| |
| p = bits - e1 * ras.target.pitch; |
| if ( ras.target.pitch > 0 ) |
| p += ( ras.target.rows - 1 ) * ras.target.pitch; |
| |
| p[0] |= f1; |
| } |
| } |
| } |
| } |
| |
| |
| static void |
| Horizontal_Sweep_Drop( RAS_ARGS Short y, |
| FT_F26Dot6 x1, |
| FT_F26Dot6 x2, |
| PProfile left, |
| PProfile right ) |
| { |
| Long e1, e2, pxl; |
| PByte bits; |
| Byte f1; |
| |
| |
| /* During the horizontal sweep, we only take care of drop-outs */ |
| |
| /* e1 + <-- pixel center */ |
| /* | */ |
| /* x1 ---+--> <-- contour */ |
| /* | */ |
| /* | */ |
| /* x2 <--+--- <-- contour */ |
| /* | */ |
| /* | */ |
| /* e2 + <-- pixel center */ |
| |
| e1 = CEILING( x1 ); |
| e2 = FLOOR ( x2 ); |
| pxl = e1; |
| |
| if ( e1 > e2 ) |
| { |
| Int dropOutControl = left->flags & 7; |
| |
| |
| if ( e1 == e2 + ras.precision ) |
| { |
| switch ( dropOutControl ) |
| { |
| case 0: /* simple drop-outs including stubs */ |
| pxl = e2; |
| break; |
| |
| case 4: /* smart drop-outs including stubs */ |
| pxl = FLOOR( ( x1 + x2 - 1 ) / 2 + ras.precision_half ); |
| break; |
| |
| case 1: /* simple drop-outs excluding stubs */ |
| case 5: /* smart drop-outs excluding stubs */ |
| /* see Vertical_Sweep_Drop for details */ |
| |
| /* rightmost stub test */ |
| if ( left->next == right && |
| left->height <= 0 && |
| !( left->flags & Overshoot_Top && |
| x2 - x1 >= ras.precision_half ) ) |
| return; |
| |
| /* leftmost stub test */ |
| if ( right->next == left && |
| left->start == y && |
| !( left->flags & Overshoot_Bottom && |
| x2 - x1 >= ras.precision_half ) ) |
| return; |
| |
| if ( dropOutControl == 1 ) |
| pxl = e2; |
| else |
| pxl = FLOOR( ( x1 + x2 - 1 ) / 2 + ras.precision_half ); |
| break; |
| |
| default: /* modes 2, 3, 6, 7 */ |
| return; /* no drop-out control */ |
| } |
| |
| /* undocumented but confirmed: If the drop-out would result in a */ |
| /* pixel outside of the bounding box, use the pixel inside of the */ |
| /* bounding box instead */ |
| if ( pxl < 0 ) |
| pxl = e1; |
| else if ( TRUNC( pxl ) >= ras.target.rows ) |
| pxl = e2; |
| |
| /* check that the other pixel isn't set */ |
| e1 = pxl == e1 ? e2 : e1; |
| |
| e1 = TRUNC( e1 ); |
| |
| bits = ras.bTarget + ( y >> 3 ); |
| f1 = (Byte)( 0x80 >> ( y & 7 ) ); |
| |
| bits -= e1 * ras.target.pitch; |
| if ( ras.target.pitch > 0 ) |
| bits += ( ras.target.rows - 1 ) * ras.target.pitch; |
| |
| if ( e1 >= 0 && |
| e1 < ras.target.rows && |
| *bits & f1 ) |
| return; |
| } |
| else |
| return; |
| } |
| |
| bits = ras.bTarget + ( y >> 3 ); |
| f1 = (Byte)( 0x80 >> ( y & 7 ) ); |
| |
| e1 = TRUNC( pxl ); |
| |
| if ( e1 >= 0 && e1 < ras.target.rows ) |
| { |
| bits -= e1 * ras.target.pitch; |
| if ( ras.target.pitch > 0 ) |
| bits += ( ras.target.rows - 1 ) * ras.target.pitch; |
| |
| bits[0] |= f1; |
| } |
| } |
| |
| |
| static void |
| Horizontal_Sweep_Step( RAS_ARG ) |
| { |
| /* Nothing, really */ |
| FT_UNUSED_RASTER; |
| } |
| |
| |
| #ifdef FT_RASTER_OPTION_ANTI_ALIASING |
| |
| |
| /*************************************************************************/ |
| /* */ |
| /* Vertical Gray Sweep Procedure Set */ |
| /* */ |
| /* These two routines are used during the vertical gray-levels sweep */ |
| /* phase by the generic Draw_Sweep() function. */ |
| /* */ |
| /* NOTES */ |
| /* */ |
| /* - The target pixmap's width *must* be a multiple of 4. */ |
| /* */ |
| /* - You have to use the function Vertical_Sweep_Span() for the gray */ |
| /* span call. */ |
| /* */ |
| /*************************************************************************/ |
| |
| static void |
| Vertical_Gray_Sweep_Init( RAS_ARGS Short* min, |
| Short* max ) |
| { |
| Long pitch, byte_len; |
| |
| |
| *min = *min & -2; |
| *max = ( *max + 3 ) & -2; |
| |
| ras.traceOfs = 0; |
| pitch = ras.target.pitch; |
| byte_len = -pitch; |
| ras.traceIncr = (Short)byte_len; |
| ras.traceG = ( *min / 2 ) * byte_len; |
| |
| if ( pitch > 0 ) |
| { |
| ras.traceG += ( ras.target.rows - 1 ) * pitch; |
| byte_len = -byte_len; |
| } |
| |
| ras.gray_min_x = (Short)byte_len; |
| ras.gray_max_x = -(Short)byte_len; |
| } |
| |
| |
| static void |
| Vertical_Gray_Sweep_Step( RAS_ARG ) |
| { |
| short* count = (short*)count_table; |
| Byte* grays; |
| |
| |
| ras.traceOfs += ras.gray_width; |
| |
| if ( ras.traceOfs > ras.gray_width ) |
| { |
| PByte pix; |
| |
| |
| pix = ras.gTarget + ras.traceG + ras.gray_min_x * 4; |
| grays = ras.grays; |
| |
| if ( ras.gray_max_x >= 0 ) |
| { |
| Long last_pixel = ras.target.width - 1; |
| Int last_cell = last_pixel >> 2; |
| Int last_bit = last_pixel & 3; |
| Bool over = 0; |
| |
| Int c1, c2; |
| PByte bit, bit2; |
| |
| |
| if ( ras.gray_max_x >= last_cell && last_bit != 3 ) |
| { |
| ras.gray_max_x = last_cell - 1; |
| over = 1; |
| } |
| |
| if ( ras.gray_min_x < 0 ) |
| ras.gray_min_x = 0; |
| |
| bit = ras.bTarget + ras.gray_min_x; |
| bit2 = bit + ras.gray_width; |
| |
| c1 = ras.gray_max_x - ras.gray_min_x; |
| |
| while ( c1 >= 0 ) |
| { |
| c2 = count[*bit] + count[*bit2]; |
| |
| if ( c2 ) |
| { |
| pix[0] = grays[(c2 >> 12) & 0x000F]; |
| pix[1] = grays[(c2 >> 8 ) & 0x000F]; |
| pix[2] = grays[(c2 >> 4 ) & 0x000F]; |
| pix[3] = grays[ c2 & 0x000F]; |
| |
| *bit = 0; |
| *bit2 = 0; |
| } |
| |
| bit++; |
| bit2++; |
| pix += 4; |
| c1--; |
| } |
| |
| if ( over ) |
| { |
| c2 = count[*bit] + count[*bit2]; |
| if ( c2 ) |
| { |
| switch ( last_bit ) |
| { |
| case 2: |
| pix[2] = grays[(c2 >> 4 ) & 0x000F]; |
| case 1: |
| pix[1] = grays[(c2 >> 8 ) & 0x000F]; |
| default: |
| pix[0] = grays[(c2 >> 12) & 0x000F]; |
| } |
| |
| *bit = 0; |
| *bit2 = 0; |
| } |
| } |
| } |
| |
| ras.traceOfs = 0; |
| ras.traceG += ras.traceIncr; |
| |
| ras.gray_min_x = 32000; |
| ras.gray_max_x = -32000; |
| } |
| } |
| |
| |
| static void |
| Horizontal_Gray_Sweep_Span( RAS_ARGS Short y, |
| FT_F26Dot6 x1, |
| FT_F26Dot6 x2, |
| PProfile left, |
| PProfile right ) |
| { |
| /* nothing, really */ |
| FT_UNUSED_RASTER; |
| FT_UNUSED( y ); |
| FT_UNUSED( x1 ); |
| FT_UNUSED( x2 ); |
| FT_UNUSED( left ); |
| FT_UNUSED( right ); |
| } |
| |
| |
| static void |
| Horizontal_Gray_Sweep_Drop( RAS_ARGS Short y, |
| FT_F26Dot6 x1, |
| FT_F26Dot6 x2, |
| PProfile left, |
| PProfile right ) |
| { |
| Long e1, e2; |
| PByte pixel; |
| |
| |
| /* During the horizontal sweep, we only take care of drop-outs */ |
| |
| e1 = CEILING( x1 ); |
| e2 = FLOOR ( x2 ); |
| |
| if ( e1 > e2 ) |
| { |
| Int dropOutControl = left->flags & 7; |
| |
| |
| if ( e1 == e2 + ras.precision ) |
| { |
| switch ( dropOutControl ) |
| { |
| case 0: /* simple drop-outs including stubs */ |
| e1 = e2; |
| break; |
| |
| case 4: /* smart drop-outs including stubs */ |
| e1 = FLOOR( ( x1 + x2 - 1 ) / 2 + ras.precision_half ); |
| break; |
| |
| case 1: /* simple drop-outs excluding stubs */ |
| case 5: /* smart drop-outs excluding stubs */ |
| /* see Vertical_Sweep_Drop for details */ |
| |
| /* rightmost stub test */ |
| if ( left->next == right && left->height <= 0 ) |
| return; |
| |
| /* leftmost stub test */ |
| if ( right->next == left && left->start == y ) |
| return; |
| |
| if ( dropOutControl == 1 ) |
| e1 = e2; |
| else |
| e1 = FLOOR( ( x1 + x2 - 1 ) / 2 + ras.precision_half ); |
| |
| break; |
| |
| default: /* modes 2, 3, 6, 7 */ |
| return; /* no drop-out control */ |
| } |
| } |
| else |
| return; |
| } |
| |
| if ( e1 >= 0 ) |
| { |
| Byte color; |
| |
| |
| if ( x2 - x1 >= ras.precision_half ) |
| color = ras.grays[2]; |
| else |
| color = ras.grays[1]; |
| |
| e1 = TRUNC( e1 ) / 2; |
| if ( e1 < ras.target.rows ) |
| { |
| pixel = ras.gTarget - e1 * ras.target.pitch + y / 2; |
| if ( ras.target.pitch > 0 ) |
| pixel += ( ras.target.rows - 1 ) * ras.target.pitch; |
| |
| if ( pixel[0] == ras.grays[0] ) |
| pixel[0] = color; |
| } |
| } |
| } |
| |
| |
| #endif /* FT_RASTER_OPTION_ANTI_ALIASING */ |
| |
| |
| /*************************************************************************/ |
| /* */ |
| /* Generic Sweep Drawing routine */ |
| /* */ |
| /*************************************************************************/ |
| |
| static Bool |
| Draw_Sweep( RAS_ARG ) |
| { |
| Short y, y_change, y_height; |
| |
| PProfile P, Q, P_Left, P_Right; |
| |
| Short min_Y, max_Y, top, bottom, dropouts; |
| |
| Long x1, x2, xs, e1, e2; |
| |
| TProfileList waiting; |
| TProfileList draw_left, draw_right; |
| |
| |
| /* initialize empty linked lists */ |
| |
| Init_Linked( &waiting ); |
| |
| Init_Linked( &draw_left ); |
| Init_Linked( &draw_right ); |
| |
| /* first, compute min and max Y */ |
| |
| P = ras.fProfile; |
| max_Y = (Short)TRUNC( ras.minY ); |
| min_Y = (Short)TRUNC( ras.maxY ); |
| |
| while ( P ) |
| { |
| Q = P->link; |
| |
| bottom = (Short)P->start; |
| top = (Short)( P->start + P->height - 1 ); |
| |
| if ( min_Y > bottom ) |
| min_Y = bottom; |
| if ( max_Y < top ) |
| max_Y = top; |
| |
| P->X = 0; |
| InsNew( &waiting, P ); |
| |
| P = Q; |
| } |
| |
| /* check the Y-turns */ |
| if ( ras.numTurns == 0 ) |
| { |
| ras.error = FT_THROW( Invalid ); |
| return FAILURE; |
| } |
| |
| /* now initialize the sweep */ |
| |
| ras.Proc_Sweep_Init( RAS_VARS &min_Y, &max_Y ); |
| |
| /* then compute the distance of each profile from min_Y */ |
| |
| P = waiting; |
| |
| while ( P ) |
| { |
| P->countL = (UShort)( P->start - min_Y ); |
| P = P->link; |
| } |
| |
| /* let's go */ |
| |
| y = min_Y; |
| y_height = 0; |
| |
| if ( ras.numTurns > 0 && |
| ras.sizeBuff[-ras.numTurns] == min_Y ) |
| ras.numTurns--; |
| |
| while ( ras.numTurns > 0 ) |
| { |
| /* check waiting list for new activations */ |
| |
| P = waiting; |
| |
| while ( P ) |
| { |
| Q = P->link; |
| P->countL -= y_height; |
| if ( P->countL == 0 ) |
| { |
| DelOld( &waiting, P ); |
| |
| if ( P->flags & Flow_Up ) |
| InsNew( &draw_left, P ); |
| else |
| InsNew( &draw_right, P ); |
| } |
| |
| P = Q; |
| } |
| |
| /* sort the drawing lists */ |
| |
| Sort( &draw_left ); |
| Sort( &draw_right ); |
| |
| y_change = (Short)ras.sizeBuff[-ras.numTurns--]; |
| y_height = (Short)( y_change - y ); |
| |
| while ( y < y_change ) |
| { |
| /* let's trace */ |
| |
| dropouts = 0; |
| |
| P_Left = draw_left; |
| P_Right = draw_right; |
| |
| while ( P_Left ) |
| { |
| x1 = P_Left ->X; |
| x2 = P_Right->X; |
| |
| if ( x1 > x2 ) |
| { |
| xs = x1; |
| x1 = x2; |
| x2 = xs; |
| } |
| |
| e1 = FLOOR( x1 ); |
| e2 = CEILING( x2 ); |
| |
| if ( x2 - x1 <= ras.precision && |
| e1 != x1 && e2 != x2 ) |
| { |
| if ( e1 > e2 || e2 == e1 + ras.precision ) |
| { |
| Int dropOutControl = P_Left->flags & 7; |
| |
| |
| if ( dropOutControl != 2 ) |
| { |
| /* a drop-out was detected */ |
| |
| P_Left ->X = x1; |
| P_Right->X = x2; |
| |
| /* mark profile for drop-out processing */ |
| P_Left->countL = 1; |
| dropouts++; |
| } |
| |
| goto Skip_To_Next; |
| } |
| } |
| |
| ras.Proc_Sweep_Span( RAS_VARS y, x1, x2, P_Left, P_Right ); |
| |
| Skip_To_Next: |
| |
| P_Left = P_Left->link; |
| P_Right = P_Right->link; |
| } |
| |
| /* handle drop-outs _after_ the span drawing -- */ |
| /* drop-out processing has been moved out of the loop */ |
| /* for performance tuning */ |
| if ( dropouts > 0 ) |
| goto Scan_DropOuts; |
| |
| Next_Line: |
| |
| ras.Proc_Sweep_Step( RAS_VAR ); |
| |
| y++; |
| |
| if ( y < y_change ) |
| { |
| Sort( &draw_left ); |
| Sort( &draw_right ); |
| } |
| } |
| |
| /* now finalize the profiles that need it */ |
| |
| P = draw_left; |
| while ( P ) |
| { |
| Q = P->link; |
| if ( P->height == 0 ) |
| DelOld( &draw_left, P ); |
| P = Q; |
| } |
| |
| P = draw_right; |
| while ( P ) |
| { |
| Q = P->link; |
| if ( P->height == 0 ) |
| DelOld( &draw_right, P ); |
| P = Q; |
| } |
| } |
| |
| /* for gray-scaling, flush the bitmap scanline cache */ |
| while ( y <= max_Y ) |
| { |
| ras.Proc_Sweep_Step( RAS_VAR ); |
| y++; |
| } |
| |
| return SUCCESS; |
| |
| Scan_DropOuts: |
| |
| P_Left = draw_left; |
| P_Right = draw_right; |
| |
| while ( P_Left ) |
| { |
| if ( P_Left->countL ) |
| { |
| P_Left->countL = 0; |
| #if 0 |
| dropouts--; /* -- this is useful when debugging only */ |
| #endif |
| ras.Proc_Sweep_Drop( RAS_VARS y, |
|