| /***************************************************************************/ |
| /* */ |
| /* ftraster.c */ |
| /* */ |
| /* The FreeType glyph rasterizer (body). */ |
| /* */ |
| /* Copyright 1996-2000 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 is a rewrite of the FreeType 1.x scan-line converter */ |
| /* */ |
| /*************************************************************************/ |
| |
| |
| #include <freetype/ftraster.h> |
| #include <freetype/internal/ftcalc.h> /* for FT_MulDiv() only */ |
| |
| |
| /*************************************************************************/ |
| /* */ |
| /* 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. */ |
| /* */ |
| /* 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 propertly. */ |
| /* */ |
| /*************************************************************************/ |
| |
| |
| /*************************************************************************/ |
| /*************************************************************************/ |
| /** **/ |
| /** CONFIGURATION MACROS **/ |
| /** **/ |
| /*************************************************************************/ |
| /*************************************************************************/ |
| |
| /* define DEBUG_RASTER if you want to compile a debugging version */ |
| #define xxxDEBUG_RASTER |
| |
| /* The default render pool size in bytes */ |
| #define RASTER_RENDER_POOL 8192 |
| |
| /* undefine FT_RASTER_OPTION_ANTI_ALIASING if you do not want to support */ |
| /* 5-levels anti-aliasing */ |
| #ifdef FT_CONFIG_OPTION_5_GRAY_LEVELS |
| #define FT_RASTER_OPTION_ANTI_ALIASING |
| #endif |
| |
| /* 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_ |
| |
| |
| /* 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 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 <freetype/internal/ftobjs.h> |
| #include <freetype/internal/ftdebug.h> /* for FT_TRACE() and FT_ERROR() */ |
| |
| |
| #endif /* _STANDALONE_ */ |
| |
| |
| #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_Gray_Unsupported -5 |
| #define Raster_Err_Unsupported -6 |
| |
| /* 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 |
| |
| /* 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 struct TPoint_ |
| { |
| Long x; |
| Long y; |
| |
| } TPoint; |
| |
| |
| typedef enum TFlow_ |
| { |
| Flow_None = 0, |
| Flow_Up = 1, |
| Flow_Down = -1 |
| |
| } TFlow; |
| |
| |
| /* States of each line, arc, and profile */ |
| typedef enum TStates_ |
| { |
| Unknown, |
| Ascending, |
| Descending, |
| Flat |
| |
| } TStates; |
| |
| |
| typedef struct TProfile_ TProfile; |
| typedef TProfile* PProfile; |
| |
| struct TProfile_ |
| { |
| FT_F26Dot6 X; /* current coordinate during sweep */ |
| PProfile link; /* link to next profile - various purpose */ |
| PLong offset; /* start of profile's data in render pool */ |
| Int flow; /* Profile orientation: Asc/Descending */ |
| Long height; /* profile's height in scanlines */ |
| Long start; /* profile's starting scanline */ |
| |
| UShort 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 TBand_ |
| { |
| Short y_min; /* band's minimum */ |
| Short y_max; /* band's maximum */ |
| |
| } TBand; |
| |
| |
| #define AlignProfileSize \ |
| ( ( sizeof ( TProfile ) + sizeof ( long ) - 1 ) / sizeof ( long ) ) |
| |
| |
| #ifdef TT_STATIC_RASTER |
| |
| #define RAS_ARGS /* void */ |
| #define RAS_ARG /* void */ |
| |
| #define RAS_VARS /* void */ |
| #define RAS_VAR /* void */ |
| |
| #define UNUSED_RASTER do ; while ( 0 ) |
| |
| #else /* TT_STATIC_RASTER */ |
| |
| #define RAS_ARGS TRaster_Instance* raster, |
| #define RAS_ARG TRaster_Instance* raster |
| |
| #define RAS_VARS raster, |
| #define RAS_VAR raster |
| |
| #define UNUSED_RASTER UNUSED( raster ) |
| |
| #endif /* TT_STATIC_RASTER */ |
| |
| |
| typedef struct TRaster_Instance_ TRaster_Instance; |
| |
| |
| /* 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 */ |
| |
| #define FLOOR( x ) ( (x) & -ras.precision ) |
| #define CEILING( x ) ( ( (x) + ras.precision - 1 ) & -ras.precision ) |
| #define TRUNC( x ) ( (signed long)(x) >> ras.precision_bits ) |
| #define FRAC( x ) ( (x) & ( ras.precision - 1 ) ) |
| #define SCALED( x ) ( ( (x) << ras.scale_shift ) - ras.precision_half ) |
| |
| /* Note that I have moved the location of some fields in the */ |
| /* structure to ensure that the most used variables are used */ |
| /* at the top. Thus, their offset can be coded with less */ |
| /* opcodes, and it results in a smaller executable. */ |
| |
| struct TRaster_Instance_ |
| { |
| Int precision_bits; /* precision related variables */ |
| Int precision; |
| Int precision_half; |
| Long precision_mask; |
| 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, 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 wether 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[2 * MaxBezier + 1]; /* The Bezier stack */ |
| |
| TBand band_stack[16]; /* band stack used for sub-banding */ |
| Int band_top; /* band stack top */ |
| |
| Int count_table[256]; /* Look-up table used to quickly count */ |
| /* set bits in a gray 2x2 cell */ |
| |
| void* memory; |
| |
| #ifdef FT_RASTER_OPTION_ANTI_ALIASING |
| |
| Byte grays[5]; /* Palette of gray levels used for */ |
| /* render. */ |
| |
| 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 */ |
| |
| #if 0 |
| PByte flags; /* current flags table */ |
| PUShort outs; /* current outlines table */ |
| FT_Vector* coords; |
| |
| UShort nPoints; /* number of points in current glyph */ |
| Short nContours; /* number of contours in current glyph */ |
| #endif |
| |
| }; |
| |
| |
| #ifdef FT_CONFIG_OPTION_STATIC_RASTER |
| |
| static TRaster_Instance cur_ras; |
| #define ras cur_ras |
| |
| #else |
| |
| #define ras (*raster) |
| |
| #endif /* FT_CONFIG_OPTION_STATIC_RASTER */ |
| |
| |
| /*************************************************************************/ |
| /*************************************************************************/ |
| /** **/ |
| /** PROFILES COMPUTATION **/ |
| /** **/ |
| /*************************************************************************/ |
| /*************************************************************************/ |
| |
| |
| /*************************************************************************/ |
| /* */ |
| /* <Function> */ |
| /* Set_High_Precision */ |
| /* */ |
| /* <Description> */ |
| /* Sets precision variables according to param flag. */ |
| /* */ |
| /* <Input> */ |
| /* High :: Set to True for high precision (typically for ppem < 18), */ |
| /* false otherwise. */ |
| /* */ |
| static |
| void Set_High_Precision( RAS_ARGS Int High ) |
| { |
| if ( High ) |
| { |
| ras.precision_bits = 10; |
| ras.precision_step = 128; |
| ras.precision_jitter = 24; |
| } |
| 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 = 1L << ras.precision_bits; |
| ras.precision_half = ras.precision / 2; |
| ras.precision_shift = ras.precision_bits - Pixel_Bits; |
| ras.precision_mask = -ras.precision; |
| } |
| |
| |
| /*************************************************************************/ |
| /* */ |
| /* <Function> */ |
| /* New_Profile */ |
| /* */ |
| /* <Description> */ |
| /* Creates a new profile in the render pool. */ |
| /* */ |
| /* <Input> */ |
| /* aState :: The state/orientation of the new profile. */ |
| /* */ |
| /* <Return> */ |
| /* SUCCESS on success. FAILURE in case of overflow or of incoherent */ |
| /* profile. */ |
| /* */ |
| static |
| Bool New_Profile( RAS_ARGS TStates aState ) |
| { |
| if ( !ras.fProfile ) |
| { |
| ras.cProfile = (PProfile)ras.top; |
| ras.fProfile = ras.cProfile; |
| ras.top += AlignProfileSize; |
| } |
| |
| if ( ras.top >= ras.maxBuff ) |
| { |
| ras.error = Raster_Err_Overflow; |
| return FAILURE; |
| } |
| |
| switch ( aState ) |
| { |
| case Ascending: |
| ras.cProfile->flow = Flow_Up; |
| FT_TRACE6(( "New ascending profile = %lx\n", (long)ras.cProfile )); |
| break; |
| |
| case Descending: |
| ras.cProfile->flow = Flow_Down; |
| FT_TRACE6(( "New descending profile = %lx\n", (long)ras.cProfile )); |
| break; |
| |
| default: |
| FT_ERROR(( "Invalid profile direction in Raster:New_Profile !!\n" )); |
| ras.error = Raster_Err_Invalid; |
| return FAILURE; |
| } |
| |
| ras.cProfile->start = 0; |
| ras.cProfile->height = 0; |
| ras.cProfile->offset = ras.top; |
| ras.cProfile->link = (PProfile)0; |
| ras.cProfile->next = (PProfile)0; |
| |
| if ( !ras.gProfile ) |
| ras.gProfile = ras.cProfile; |
| |
| ras.state = aState; |
| ras.fresh = TRUE; |
| ras.joint = FALSE; |
| |
| return SUCCESS; |
| } |
| |
| |
| /*************************************************************************/ |
| /* */ |
| /* <Function> */ |
| /* End_Profile */ |
| /* */ |
| /* <Description> */ |
| /* Finalizes the current profile. */ |
| /* */ |
| /* <Return> */ |
| /* SUCCESS on success. FAILURE in case of overflow or incoherency. */ |
| /* */ |
| static |
| Bool End_Profile( RAS_ARG ) |
| { |
| Long h; |
| PProfile oldProfile; |
| |
| |
| h = ras.top - ras.cProfile->offset; |
| |
| if ( h < 0 ) |
| { |
| FT_ERROR(( "Negative height encountered in End_Profile!\n" )); |
| ras.error = Raster_Err_Neg_Height; |
| return FAILURE; |
| } |
| |
| if ( h > 0 ) |
| { |
| FT_TRACE6(( "Ending profile %lx, start = %ld, height = %ld\n", |
| (long)ras.cProfile, ras.cProfile->start, h )); |
| |
| oldProfile = ras.cProfile; |
| ras.cProfile->height = h; |
| 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 = Raster_Err_Overflow; |
| return FAILURE; |
| } |
| |
| ras.joint = FALSE; |
| |
| return SUCCESS; |
| } |
| |
| |
| /*************************************************************************/ |
| /* */ |
| /* <Function> */ |
| /* Insert_Y_Turn */ |
| /* */ |
| /* <Description> */ |
| /* Inserts 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 y2, 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 ) |
| { |
| y2 = y_turns[n]; |
| y_turns[n] = y; |
| y = y2; |
| n--; |
| } |
| |
| if ( n < 0 ) |
| { |
| if ( ras.maxBuff <= ras.top ) |
| { |
| ras.error = Raster_Err_Overflow; |
| return FAILURE; |
| } |
| ras.maxBuff--; |
| ras.numTurns++; |
| ras.sizeBuff[-ras.numTurns] = y; |
| } |
| |
| return SUCCESS; |
| } |
| |
| |
| /*************************************************************************/ |
| /* */ |
| /* <Function> */ |
| /* Finalize_Profile_Table */ |
| /* */ |
| /* <Description> */ |
| /* Adjusts all links in the profiles list. */ |
| /* */ |
| /* <Return> */ |
| /* SUCCESS on success. FAILURE in case of overflow. */ |
| /* */ |
| static |
| Bool Finalize_Profile_Table( RAS_ARG ) |
| { |
| Int bottom, top; |
| UShort n; |
| PProfile p; |
| |
| |
| n = ras.num_Profs; |
| |
| if ( n > 1 ) |
| { |
| p = ras.fProfile; |
| while ( n > 0 ) |
| { |
| if ( n > 1 ) |
| p->link = (PProfile)( p->offset + p->height ); |
| else |
| p->link = NULL; |
| |
| switch ( p->flow ) |
| { |
| case Flow_Down: |
| bottom = p->start - p->height+1; |
| top = p->start; |
| p->start = bottom; |
| p->offset += p->height - 1; |
| break; |
| |
| case Flow_Up: |
| default: |
| bottom = p->start; |
| top = p->start + 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> */ |
| /* Subdivides 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 too good at common expression */ |
| /* substitution and instruction scheduling ;-) */ |
| } |
| |
| |
| /*************************************************************************/ |
| /* */ |
| /* <Function> */ |
| /* Split_Cubic */ |
| /* */ |
| /* <Description> */ |
| /* Subdivides 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> */ |
| /* Computes the x-coordinates of an ascending line segment and stores */ |
| /* 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 = TRUNC( miny ); |
| f1 = 0; |
| } |
| else |
| { |
| e1 = TRUNC( y1 ); |
| f1 = FRAC( y1 ); |
| } |
| |
| if ( y2 > maxy ) |
| { |
| /* x2 += FMulDiv( Dx, maxy - y2, Dy ); UNNECESSARY */ |
| e2 = TRUNC( maxy ); |
| f2 = 0; |
| } |
| else |
| { |
| e2 = TRUNC( y2 ); |
| f2 = FRAC( y2 ); |
| } |
| |
| if ( f1 > 0 ) |
| { |
| if ( e1 == e2 ) |
| return SUCCESS; |
| else |
| { |
| x1 += FMulDiv( Dx, ras.precision - f1, Dy ); |
| e1 += 1; |
| } |
| } |
| else |
| if ( ras.joint ) |
| { |
| ras.top--; |
| ras.joint = FALSE; |
| } |
| |
| ras.joint = ( f2 == 0 ); |
| |
| if ( ras.fresh ) |
| { |
| ras.cProfile->start = e1; |
| ras.fresh = FALSE; |
| } |
| |
| size = e2 - e1 + 1; |
| if ( ras.top + size >= ras.maxBuff ) |
| { |
| ras.error = Raster_Err_Overflow; |
| return FAILURE; |
| } |
| |
| if ( Dx > 0 ) |
| { |
| Ix = ( ras.precision * Dx ) / Dy; |
| Rx = ( ras.precision * Dx ) % Dy; |
| Dx = 1; |
| } |
| else |
| { |
| Ix = -( ( 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> */ |
| /* Computes the x-coordinates of an descending line segment and */ |
| /* stores 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> */ |
| /* Computes the x-coordinates of an ascending Bezier arc and stores */ |
| /* 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 = 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 = Raster_Err_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> */ |
| /* Computes the x-coordinates of an descending Bezier arc and stores */ |
| /* 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> */ |
| /* Injects a new line segment and adjusts 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: |
| if ( y > ras.lastY ) |
| { |
| if ( New_Profile( RAS_VARS Ascending ) ) |
| return FAILURE; |
| } |
| else |
| { |
| if ( y < ras.lastY ) |
| if ( New_Profile( RAS_VARS Descending ) ) |
| return FAILURE; |
| } |
| break; |
| |
| case Ascending: |
| if ( y < ras.lastY ) |
| { |
| if ( End_Profile( RAS_VAR ) || |
| New_Profile( RAS_VARS Descending ) ) |
| return FAILURE; |
| } |
| break; |
| |
| case Descending: |
| if ( y > ras.lastY ) |
| { |
| if ( End_Profile( RAS_VAR ) || |
| New_Profile( RAS_VARS Ascending ) ) |
| return FAILURE; |
| } |
| break; |
| |
| default: |
| ; |
| } |
| |
| /* Then compute the lines */ |
| |
| switch ( ras.state ) |
| { |
| case Ascending: |
| if ( Line_Up ( RAS_VARS ras.lastX, ras.lastY, |
| x, y, ras.minY, ras.maxY ) ) |
| return FAILURE; |
| break; |
| |
| case Descending: |
| 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> */ |
| /* Injects a new conic arc and adjusts 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 : Descending; |
| if ( ras.state != state_bez ) |
| { |
| /* finalize current profile if any */ |
| if ( ras.state != Unknown && |
| End_Profile( RAS_VAR ) ) |
| goto Fail; |
| |
| /* create a new profile */ |
| if ( New_Profile( RAS_VARS state_bez ) ) |
| goto Fail; |
| } |
| |
| /* now call the appropriate routine */ |
| if ( state_bez == Ascending ) |
| { |
| 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> */ |
| /* Injects a new cubic arc and adjusts 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 : Descending; |
| |
| /* detect a change of direction */ |
| if ( ras.state != state_bez ) |
| { |
| if ( ras.state != Unknown && |
| End_Profile( RAS_VAR ) ) |
| goto Fail; |
| |
| if ( New_Profile( RAS_VARS state_bez ) ) |
| goto Fail; |
| } |
| |
| /* compute intersections */ |
| if ( state_bez == Ascending ) |
| { |
| 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> */ |
| /* Scans the outline arays 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; |
| |
| char 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; |
| 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 ); |
| x3 = SCALED( point[ 0].x ); |
| y3 = SCALED( point[ 0].y ); |
| |
| if ( flipped ) |
| { |
| SWAP_( x1, y1 ); |
| SWAP_( x2, y2 ); |
| SWAP_( x3, y3 ); |
| } |
| |
| if ( point <= limit ) |
| { |
| 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 = Raster_Err_Invalid; |
| |
| Fail: |
| return FAILURE; |
| } |
| |
| |
| /*************************************************************************/ |
| /* */ |
| /* <Function> */ |
| /* Convert_Glyph */ |
| /* */ |
| /* <Description> */ |
| /* Converts a glyph into a series of segments and arcs and makes 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 ) |
| { |
| Short i; |
| UShort start; |
| |
| PProfile lastProfile; |
| |
| |
| 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++ ) |
| { |
| ras.state = Unknown; |
| ras.gProfile = NULL; |
| |
| if ( Decompose_Curve( RAS_VARS start, ras.outline.contours[i], flipped ) ) |
| return FAILURE; |
| |
| start = ras.outline.contours[i] + 1; |
| |
| /* We must now see 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->flow == ras.cProfile->flow ) |
| ras.top--; |
| /* Note that ras.gProfile can be nil if the contour was too small */ |
| /* to be drawn. */ |
| |
| lastProfile = ras.cProfile; |
| if ( End_Profile( RAS_VAR ) ) |
| 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 ( 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. */ |
| } |
| |
| |
| /*************************************************************************/ |
| /* */ |
| /* Update */ |
| /* */ |
| /* Update all X offsets of a drawing list. */ |
| /* */ |
| static |
| void Update( PProfile first ) |
| { |
| PProfile current = first; |
| |
| |
| while ( current ) |
| { |
| current->X = *current->offset; |
| current->offset += current->flow; |
| current->height--; |
| current = current->link; |
| } |
| } |
| |
| |
| /*************************************************************************/ |
| /* */ |
| /* 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 */ |
| Update( *list ); |
| |
| /* 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; |
| |
| 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; |
| Short c1, c2; |
| Byte f1, f2; |
| Byte* target; |
| |
| UNUSED( y ); |
| UNUSED( left ); |
| 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 ) |
| { |
| if ( e1 < 0 ) e1 = 0; |
| if ( e2 >= ras.bWidth ) e2 = ras.bWidth - 1; |
| |
| c1 = (Short)( e1 >> 3 ); |
| c2 = (Short)( e2 >> 3 ); |
| |
| f1 = (unsigned char)0xFF >> ( e1 & 7 ); |
| f2 = ~((unsigned char)0x7F >> ( e2 & 7 )); |
| |
| if ( ras.gray_min_x > c1 ) ras.gray_min_x = c1; |
| if ( ras.gray_max_x < c2 ) ras.gray_max_x = 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; |
| Short c1, f1; |
| |
| |
| /* Drop-out control */ |
| |
| e1 = CEILING( x1 ); |
| e2 = FLOOR ( x2 ); |
| |
| if ( e1 > e2 ) |
| { |
| if ( e1 == e2 + ras.precision ) |
| { |
| switch ( ras.dropOutControl ) |
| { |
| case 1: |
| e1 = e2; |
| break; |
| |
| case 4: |
| e1 = CEILING( (x1 + x2 + 1) / 2 ); |
| break; |
| |
| case 2: |
| case 5: |
| /* Drop-out Control Rule #4 */ |
| |
| /* The spec is not very clear regarding rule #4. It */ |
| /* presents a method that is way too costly to implement */ |
| /* while the general idea seems to get rid of `stubs'. */ |
| /* */ |
| /* Here, we only get rid of stubs recognized if: */ |
| /* */ |
| /* 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 */ |
| /* */ |
| |
| /* FIXXXME: uncommenting this line solves the disappearing */ |
| /* bit problem in the `7' of verdana 10pts, but */ |
| /* makes a new one in the `C' of arial 14pts */ |
| |
| #if 0 |
| if ( x2 - x1 < ras.precision_half ) |
| #endif |
| { |
| /* upper stub test */ |
| if ( left->next == right && left->height <= 0 ) |
| return; |
| |
| /* lower stub test */ |
| if ( right->next == left && left->start == y ) |
| return; |
| } |
| |
| /* check that the rightmost pixel isn't set */ |
| |
| e1 = TRUNC( e1 ); |
| |
| c1 = (Short)( e1 >> 3 ); |
| f1 = e1 & 7; |
| |
| if ( e1 >= 0 && e1 < ras.bWidth && |
| ras.bTarget[ras.traceOfs + c1] & ( 0x80 >> f1 ) ) |
| return; |
| |
| if ( ras.dropOutControl == 2 ) |
| e1 = e2; |
| else |
| e1 = CEILING( ( x1 + x2 + 1 ) / 2 ); |
| |
| break; |
| |
| default: |
| return; /* unsupported mode */ |
| } |
| } |
| else |
| return; |
| } |
| |
| e1 = TRUNC( e1 ); |
| |
| if ( e1 >= 0 && e1 < ras.bWidth ) |
| { |
| c1 = (Short)( e1 >> 3 ); |
| f1 = 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 */ |
| UNUSED( raster ); |
| UNUSED( min ); |
| UNUSED( max ); |
| } |
| |
| |
| static |
| void Horizontal_Sweep_Span( RAS_ARGS Short y, |
| FT_F26Dot6 x1, |
| FT_F26Dot6 x2, |
| PProfile left, |
| PProfile right ) |
| { |
| Long e1, e2; |
| PByte bits; |
| Byte f1; |
| |
| UNUSED( left ); |
| UNUSED( right ); |
| |
| |
| if ( x2 - x1 < ras.precision ) |
| { |
| e1 = CEILING( x1 ); |
| e2 = FLOOR ( x2 ); |
| |
| if ( e1 == e2 ) |
| { |
| 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; |
| PByte bits; |
| Byte f1; |
| |
| |
| /* During the horizontal sweep, we only take care of drop-outs */ |
| |
| e1 = CEILING( x1 ); |
| e2 = FLOOR ( x2 ); |
| |
| if ( e1 > e2 ) |
| { |
| if ( e1 == e2 + ras.precision ) |
| { |
| switch ( ras.dropOutControl ) |
| { |
| case 1: |
| e1 = e2; |
| break; |
| |
| case 4: |
| e1 = CEILING( ( x1 + x2 + 1 ) / 2 ); |
| break; |
| |
| case 2: |
| case 5: |
| |
| /* Drop-out Control Rule #4 */ |
| |
| /* The spec is not very clear regarding rule #4. It */ |
| /* presents a method that is way too costly to implement */ |
| /* while the general idea seems to get rid of `stubs'. */ |
| /* */ |
| |
| /* rightmost stub test */ |
| if ( left->next == right && left->height <= 0 ) |
| return; |
| |
| /* leftmost stub test */ |
| if ( right->next == left && left->start == y ) |
| return; |
| |
| /* check that the rightmost pixel isn't set */ |
| |
| 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; |
| |
| if ( ras.dropOutControl == 2 ) |
| e1 = e2; |
| else |
| e1 = CEILING( ( x1 + x2 + 1 ) / 2 ); |
| |
| break; |
| |
| default: |
| return; /* unsupported mode */ |
| } |
| } |
| else |
| return; |
| } |
| |
| bits = ras.bTarget + ( y >> 3 ); |
| f1 = (Byte)( 0x80 >> ( y & 7 ) ); |
| |
| e1 = TRUNC( e1 ); |
| |
| 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 */ |
| 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 ) |
| { |
| Int c1, c2; |
| PByte pix, bit, bit2; |
| Int* count = ras.count_table; |
| Byte* grays; |
| |
| |
| ras.traceOfs += ras.gray_width; |
| |
| if ( ras.traceOfs > ras.gray_width ) |
| { |
| 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; |
| |
| 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 */ |
| UNUSED( raster ); |
| UNUSED( y ); |
| UNUSED( x1 ); |
| UNUSED( x2 ); |
| UNUSED( left ); |
| 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; |
| Byte color; |
| |
| |
| /* During the horizontal sweep, we only take care of drop-outs */ |
| e1 = CEILING( x1 ); |
| e2 = FLOOR ( x2 ); |
| |
| if ( e1 > e2 ) |
| { |
| if ( e1 == e2 + ras.precision ) |
| { |
| switch ( ras.dropOutControl ) |
| { |
| case 1: |
| e1 = e2; |
| break; |
| |
| case 4: |
| e1 = CEILING( ( x1 + x2 + 1 ) / 2 ); |
| break; |
| |
| case 2: |
| case 5: |
| |
| /* Drop-out Control Rule #4 */ |
| |
| /* The spec is not very clear regarding rule #4. It */ |
| /* presents a method that is way too costly to implement */ |
| /* while the general idea seems to get rid of `stubs'. */ |
| /* */ |
| |
| /* rightmost stub test */ |
| if ( left->next == right && left->height <= 0 ) |
| return; |
| |
| /* leftmost stub test */ |
| if ( right->next == left && left->start == y ) |
| return; |
| |
| if ( ras.dropOutControl == 2 ) |
| e1 = e2; |
| else |
| e1 = CEILING( ( x1 + x2 + 1 ) / 2 ); |
| |
| break; |
| |
| default: |
| return; /* unsupported mode */ |
| } |
| } |
| else |
| return; |
| } |
| |
| if ( e1 >= 0 ) |
| { |
| 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 wait; |
| TProfileList draw_left, draw_right; |
| |
| |
| /* Init empty linked lists */ |
| |
| Init_Linked( &wait ); |
| |
| 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( &wait, P ); |
| |
| P = Q; |
| } |
| |
| /* Check the Y-turns */ |
| if ( ras.numTurns == 0 ) |
| { |
| ras.error = Raster_Err_Invalid; |
| return FAILURE; |
| } |
| |
| /* Now inits the sweep */ |
| |
| ras.Proc_Sweep_Init( RAS_VARS &min_Y, &max_Y ); |
| |
| /* Then compute the distance of each profile from min_Y */ |
| |
| P = wait; |
| |
| while ( P ) |
| { |
| P->countL = 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 ) |
| { |
| /* look in the wait list for new activations */ |
| |
| P = wait; |
| |
| while ( P ) |
| { |
| Q = P->link; |
| P->countL -= y_height; |
| if ( P->countL == 0 ) |
| { |
| DelOld( &wait, P ); |
| |
| switch ( P->flow ) |
| { |
| case Flow_Up: |
| InsNew( &draw_left, P ); |
| break; |
| |
| case Flow_Down: |
| InsNew( &draw_right, P ); |
| break; |
| } |
| } |
| |
| P = Q; |
| } |
| |
| /* Sort the drawing lists */ |
| |
| Sort( &draw_left ); |
| Sort( &draw_right ); |
| |
| y_change = (Short)ras.sizeBuff[-ras.numTurns--]; |
| y_height = 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; |
| } |
| |
| if ( x2 - x1 <= ras.precision ) |
| { |
| e1 = FLOOR( x1 ); |
| e2 = CEILING( x2 ); |
| |
| if ( ras.dropOutControl != 0 && |
| ( e1 > e2 || e2 == e1 + ras.precision ) ) |
| { |
| /* 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; |
| } |
| |
| /* now perform the dropouts _after_ the span drawing */ |
| /* drop-outs 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 needs it */ |
| |
| { |
| PProfile Q, P; |
| |
| |
| P = draw_left; |
| while ( P ) |
| { |
| Q = P->link; |
| if ( P->height == 0 ) |
| DelOld( &draw_left, P ); |
| P = Q; |
| } |
| } |
| |
| { |
| PProfile Q, P = draw_right; |
| |
| |
| while ( P ) |
| { |
| Q = P->link; |
| if ( P->height == 0 ) |
| DelOld( &draw_right, P ); |
| P = Q; |
| } |
| } |
| } |
| |
| /* for gray-scaling, flushes 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, |
| P_Left->X, |
| P_Right->X, |
| P_Left, |
| P_Right ); |
| } |
| |
| P_Left = P_Left->link; |
| P_Right = P_Right->link; |
| } |
| |
| goto Next_Line; |
| } |
| |
| |
| /*************************************************************************/ |
| /* */ |
| /* <Function> */ |
| /* Render_Single_Pass */ |
| /* */ |
| /* <Description> */ |
| /* Performs one sweep with sub-banding. */ |
| /* */ |
| /* <Input> */ |
| /* flipped :: If set, flip the direction of the outline. */ |
| /* */ |
| /* <Return> */ |
| /* Renderer error code. */ |
| /* */ |
| static |
| int Render_Single_Pass( RAS_ARGS Bool flipped ) |
| { |
| Short i, j, k; |
| |
| |
| while ( ras.band_top >= 0 ) |
| { |
| ras.maxY = (Long)ras.band_stack[ras.band_top].y_max * ras.precision; |
| ras.minY = (Long)ras.band_stack[ras.band_top].y_min * ras.precision; |
| |
| ras.top = ras.buff; |
| |
| ras.error = Raster_Err_None; |
| |
| if ( Convert_Glyph( RAS_VARS flipped ) ) |
| { |
| if ( ras.error != Raster_Err_Overflow ) |
| return FAILURE; |
| |
| ras.error = Raster_Err_None; |
| |
| /* sub-banding */ |
| |
| #ifdef DEBUG_RASTER |
| ClearBand( RAS_VARS TRUNC( ras.minY ), TRUNC( ras.maxY ) ); |
| #endif |
| |
| i = ras.band_stack[ras.band_top].y_min; |
| j = ras.band_stack[ras.band_top].y_max; |
| |
| k = ( i + j ) / 2; |
| |
| if ( ras.band_top >= 7 || k < i ) |
| { |
| ras.band_top = 0; |
| ras.error = Raster_Err_Invalid; |
| |
| return ras.error; |
| } |
| |
| ras.band_stack[ras.band_top + 1].y_min = k; |
| ras.band_stack[ras.band_top + 1].y_max = j; |
| |
| ras.band_stack[ras.band_top].y_max = k - 1; |
| |
| ras.band_top++; |
| } |
| else |
| { |
| if ( ras.fProfile ) |
| if ( Draw_Sweep( RAS_VAR ) ) |
| return ras.error; |
| ras.band_top--; |
| } |
| } |
| |
| return SUCCESS; |
| } |
| |
| |
| /*************************************************************************/ |
| /* */ |
| /* <Function> */ |
| /* Render_Glyph */ |
| /* */ |
| /* <Description> */ |
| /* Renders a glyph in a bitmap. Sub-banding if needed. */ |
| /* */ |
| /* <Return> */ |
| /* FreeType error code. 0 means success. */ |
| /* */ |
| /* XXX Fixme: ftraster's error codes don't harmonize with FT2's ones! */ |
| /* */ |
| LOCAL_FUNC |
| FT_Error Render_Glyph( RAS_ARG ) |
| { |
| FT_Error error; |
| |
| |
| Set_High_Precision( RAS_VARS ras.outline.flags & |
| ft_outline_high_precision ); |
| ras.scale_shift = ras.precision_shift; |
| ras.dropOutControl = 2; |
| ras.second_pass = !( ras.outline.flags & ft_outline_single_pass ); |
| |
| /* Vertical Sweep */ |
| ras.Proc_Sweep_Init = Vertical_Sweep_Init; |
| ras.Proc_Sweep_Span = Vertical_Sweep_Span; |
| ras.Proc_Sweep_Drop = Vertical_Sweep_Drop; |
| ras.Proc_Sweep_Step = Vertical_Sweep_Step; |
| |
| ras.band_top = 0; |
| ras.band_stack[0].y_min = 0; |
| ras.band_stack[0].y_max = ras.target.rows - 1; |
| |
| ras.bWidth = ras.target.width; |
| ras.bTarget = (Byte*)ras.target.buffer; |
| |
| if ( ( error = Render_Single_Pass( RAS_VARS 0 ) ) != 0 ) |
| return error; |
| |
| /* Horizontal Sweep */ |
| if ( ras.second_pass && ras.dropOutControl != 0 ) |
| { |
| ras.Proc_Sweep_Init = Horizontal_Sweep_Init; |
| ras.Proc_Sweep_Span = Horizontal_Sweep_Span; |
| ras.Proc_Sweep_Drop = Horizontal_Sweep_Drop; |
| ras.Proc_Sweep_Step = Horizontal_Sweep_Step; |
| |
| ras.band_top = 0; |
| ras.band_stack[0].y_min = 0; |
| ras.band_stack[0].y_max = ras.target.width - 1; |
| |
| if ( ( error = Render_Single_Pass( RAS_VARS 1 ) ) != 0 ) |
| return error; |
| } |
| |
| return FT_Err_Ok; |
| } |
| |
| |
| #ifdef FT_RASTER_OPTION_ANTI_ALIASING |
| |
| |
| /*************************************************************************/ |
| /* */ |
| /* <Function> */ |
| /* Render_Gray_Glyph */ |
| /* */ |
| /* <Description> */ |
| /* Renders a glyph with grayscaling. Sub-banding if needed. */ |
| /* */ |
| /* <Return> */ |
| /* FreeType error code. 0 means success. */ |
| /* */ |
| LOCAL_FUNC |
| FT_Error Render_Gray_Glyph( RAS_ARG ) |
| { |
| Long pixel_width; |
| FT_Error error; |
| |
| |
| Set_High_Precision( RAS_VARS ras.outline.flags & |
| ft_outline_high_precision ); |
| ras.scale_shift = ras.precision_shift + 1; |
| ras.dropOutControl = 2; |
| ras.second_pass = !( ras.outline.flags & ft_outline_single_pass ); |
| |
| |
| /* Vertical Sweep */ |
| |
| ras.band_top = 0; |
| ras.band_stack[0].y_min = 0; |
| ras.band_stack[0].y_max = 2 * ras.target.rows - 1; |
| |
| ras.bWidth = ras.gray_width; |
| pixel_width = 2 * ( ( ras.target.width + 3 ) >> 2 ); |
| |
| if ( ras.bWidth > pixel_width ) |
| ras.bWidth = pixel_width; |
| |
| ras.bWidth = ras.bWidth * 8; |
| ras.bTarget = (Byte*)ras.gray_lines; |
| ras.gTarget = (Byte*)ras.target.buffer; |
| |
| ras.Proc_Sweep_Init = Vertical_Gray_Sweep_Init; |
| ras.Proc_Sweep_Span = Vertical_Sweep_Span; |
| ras.Proc_Sweep_Drop = Vertical_Sweep_Drop; |
| ras.Proc_Sweep_Step = Vertical_Gray_Sweep_Step; |
| |
| error = Render_Single_Pass( RAS_VARS 0 ); |
| if (error) |
| return error; |
| |
| /* Horizontal Sweep */ |
| if ( ras.second_pass && ras.dropOutControl != 0 ) |
| { |
| ras.Proc_Sweep_Init = Horizontal_Sweep_Init; |
| ras.Proc_Sweep_Span = Horizontal_Gray_Sweep_Span; |
| ras.Proc_Sweep_Drop = Horizontal_Gray_Sweep_Drop; |
| ras.Proc_Sweep_Step = Horizontal_Sweep_Step; |
| |
| ras.band_top = 0; |
| ras.band_stack[0].y_min = 0; |
| ras.band_stack[0].y_max = ras.target.width * 2 - 1; |
| |
| error = Render_Single_Pass( RAS_VARS 1 ); |
| if (error) |
| return error; |
| } |
| |
| return FT_Err_Ok; |
| } |
| |
| #else /* FT_RASTER_OPTION_ANTI_ALIASING */ |
| |
| LOCAL_FUNC |
| FT_Error Render_Gray_Glyph( RAS_ARG ) |
| { |
| UNUSED_RASTER; |
| return Raster_Err_Unsupported; |
| } |
| |
| #endif |
| |
| |
| static |
| void ft_black_init( TRaster_Instance* raster ) |
| { |
| FT_UInt n; |
| FT_ULong c; |
| |
| /* setup count table */ |
| for ( n = 0; n < 256; n++ ) |
| { |
| c = ( n & 0x55 ) + ( ( n & 0xAA ) >> 1 ); |
| |
| c = ( ( c << 6 ) & 0x3000 ) | |
| ( ( c << 4 ) & 0x0300 ) | |
| ( ( c << 2 ) & 0x0030 ) | |
| (c & 0x0003 ); |
| |
| raster->count_table[n] = c; |
| } |
| |
| /* set default 5-levels gray palette */ |
| for ( n = 0; n < 5; n++ ) |
| raster->grays[n] = n * 255 / 4; |
| |
| raster->gray_width = RASTER_GRAY_LINES / 2; |
| } |
| |
| /**** RASTER OBJECT CREATION: In standalone mode, we simply use *****/ |
| /**** a static object. *****/ |
| |
| #ifdef _STANDALONE_ |
| |
| |
| static |
| int ft_black_new( void* memory, |
| FT_Raster *araster ) |
| { |
| static FT_RasterRec_ the_raster; |
| |
| |
| *araster = &the_raster; |
| memset( &the_raster, sizeof ( the_raster ), 0 ); |
| ft_black_init( &the_raster ); |
| |
| return 0; |
| } |
| |
| |
| static |
| void ft_black_done( FT_Raster raster ) |
| { |
| /* nothing */ |
| raster->init = 0; |
| } |
| |
| |
| #else /* _STANDALONE_ */ |
| |
| |
| static |
| int ft_black_new( FT_Memory memory, |
| TRaster_Instance** araster ) |
| { |
| FT_Error error; |
| TRaster_Instance* raster; |
| |
| |
| *araster = 0; |
| if ( !ALLOC( raster, sizeof ( *raster ) ) ) |
| { |
| raster->memory = memory; |
| ft_black_init( raster ); |
| |
| *araster = raster; |
| } |
| |
| return error; |
| } |
| |
| |
| static |
| void ft_black_done( TRaster_Instance* raster ) |
| { |
| FT_Memory memory = (FT_Memory)raster->memory; |
| FREE( raster ); |
| } |
| |
| |
| #endif /* _STANDALONE_ */ |
| |
| |
| static |
| void ft_black_reset( TRaster_Instance* raster, |
| const char* pool_base, |
| long pool_size ) |
| { |
| if ( raster && pool_base && pool_size >= 4096 ) |
| { |
| /* save the pool */ |
| raster->buff = (PLong)pool_base; |
| raster->sizeBuff = raster->buff + pool_size / sizeof ( Long ); |
| } |
| } |
| |
| |
| static |
| void ft_black_set_mode( TRaster_Instance* raster, |
| unsigned long mode, |
| const char* palette ) |
| { |
| if ( mode == FT_MAKE_TAG( 'p', 'a', 'l', '5' ) ) |
| { |
| /* set 5-levels gray palette */ |
| raster->grays[0] = palette[0]; |
| raster->grays[1] = palette[1]; |
| raster->grays[2] = palette[2]; |
| raster->grays[3] = palette[3]; |
| raster->grays[4] = palette[4]; |
| } |
| } |
| |
| |
| static |
| int ft_black_render( TRaster_Instance* raster, |
| FT_Raster_Params* params ) |
| { |
| FT_Outline* outline = (FT_Outline*)params->source; |
| FT_Bitmap* target_map = params->target; |
| |
| |
| if ( !raster || !raster->buff || !raster->sizeBuff ) |
| return Raster_Err_Not_Ini; |
| |
| if ( !outline || !outline->contours || !outline->points ) |
| return Raster_Err_Invalid; |
| |
| /* return immediately if the outline is empty */ |
| if ( outline->n_points == 0 || outline->n_contours <= 0 ) |
| return Raster_Err_None; |
| |
| if ( outline->n_points != outline->contours[outline->n_contours - 1] + 1 ) |
| return Raster_Err_Invalid; |
| |
| if ( !target_map || !target_map->buffer ) |
| return Raster_Err_Invalid; |
| |
| /* this version of the raster does not support direct rendering, sorry */ |
| if ( params->flags & ft_raster_flag_direct ) |
| return Raster_Err_Unsupported; |
| |
| ras.outline = *outline; |
| ras.target = *target_map; |
| |
| return ( params->flags & ft_raster_flag_aa |
| ? Render_Gray_Glyph( raster ) |
| : Render_Glyph( raster ) ); |
| } |
| |
| |
| FT_Raster_Funcs ft_default_raster = |
| { |
| ft_glyph_format_outline, |
| (FT_Raster_New_Func) ft_black_new, |
| (FT_Raster_Reset_Func) ft_black_reset, |
| (FT_Raster_Set_Mode_Func)ft_black_set_mode, |
| (FT_Raster_Render_Func) ft_black_render, |
| (FT_Raster_Done_Func) ft_black_done |
| }; |
| |
| |
| /* END */ |