Edit
kc3-lang/freetype/src/psaux/t1decode.c
Werner Lemberg
- src/psaux/t1decode.c
-
/***************************************************************************/ /* */ /* t1decode.c */ /* */ /* PostScript Type 1 decoding routines (body). */ /* */ /* Copyright 2000-2001 by */ /* David Turner, Robert Wilhelm, and Werner Lemberg. */ /* */ /* This file is part of the FreeType project, and may only be used, */ /* modified, and distributed under the terms of the FreeType project */ /* license, LICENSE.TXT. By continuing to use, modify, or distribute */ /* this file you indicate that you have read the license and */ /* understand and accept it fully. */ /* */ /***************************************************************************/ #include <ft2build.h> #include FT_INTERNAL_DEBUG_H #include FT_OUTLINE_H #include "t1decode.h" #include "psobjs.h" #include "psauxerr.h" /*************************************************************************/ /* */ /* The macro FT_COMPONENT is used in trace mode. It is an implicit */ /* parameter of the FT_TRACE() and FT_ERROR() macros, used to print/log */ /* messages during execution. */ /* */ #undef FT_COMPONENT #define FT_COMPONENT trace_t1decode typedef enum T1_Operator_ { op_none = 0, op_endchar, op_hsbw, op_seac, op_sbw, op_closepath, op_hlineto, op_hmoveto, op_hvcurveto, op_rlineto, op_rmoveto, op_rrcurveto, op_vhcurveto, op_vlineto, op_vmoveto, op_dotsection, op_hstem, op_hstem3, op_vstem, op_vstem3, op_div, op_callothersubr, op_callsubr, op_pop, op_return, op_setcurrentpoint, op_max /* never remove this one */ } T1_Operator; static const FT_Int t1_args_count[op_max] = { 0, /* none */ 0, /* endchar */ 2, /* hsbw */ 5, /* seac */ 4, /* sbw */ 0, /* closepath */ 1, /* hlineto */ 1, /* hmoveto */ 4, /* hvcurveto */ 2, /* rlineto */ 2, /* rmoveto */ 6, /* rrcurveto */ 4, /* vhcurveto */ 1, /* vlineto */ 1, /* vmoveto */ 0, /* dotsection */ 2, /* hstem */ 6, /* hstem3 */ 2, /* vstem */ 6, /* vstem3 */ 2, /* div */ -1, /* callothersubr */ 1, /* callsubr */ 0, /* pop */ 0, /* return */ 2 /* setcurrentpoint */ }; /*************************************************************************/ /* */ /* <Function> */ /* t1_lookup_glyph_by_stdcharcode */ /* */ /* <Description> */ /* Looks up a given glyph by its StandardEncoding charcode. Used to */ /* implement the SEAC Type 1 operator. */ /* */ /* <Input> */ /* face :: The current face object. */ /* */ /* charcode :: The character code to look for. */ /* */ /* <Return> */ /* A glyph index in the font face. Returns -1 if the corresponding */ /* glyph wasn't found. */ /* */ static FT_Int t1_lookup_glyph_by_stdcharcode( T1_Decoder* decoder, FT_Int charcode ) { FT_UInt n; const FT_String* glyph_name; PSNames_Interface* psnames = decoder->psnames; /* check range of standard char code */ if ( charcode < 0 || charcode > 255 ) return -1; glyph_name = psnames->adobe_std_strings( psnames->adobe_std_encoding[charcode]); for ( n = 0; n < decoder->num_glyphs; n++ ) { FT_String* name = (FT_String*)decoder->glyph_names[n]; if ( name && strcmp( name,glyph_name ) == 0 ) return n; } return -1; } /*************************************************************************/ /* */ /* <Function> */ /* t1operator_seac */ /* */ /* <Description> */ /* Implements the `seac' Type 1 operator for a Type 1 decoder. */ /* */ /* <Input> */ /* decoder :: The current CID decoder. */ /* */ /* asb :: The accent's side bearing. */ /* */ /* adx :: The horizontal offset of the accent. */ /* */ /* ady :: The vertical offset of the accent. */ /* */ /* bchar :: The base character's StandardEncoding charcode. */ /* */ /* achar :: The accent character's StandardEncoding charcode. */ /* */ /* <Return> */ /* FreeType error code. 0 means success. */ /* */ static FT_Error t1operator_seac( T1_Decoder* decoder, FT_Pos asb, FT_Pos adx, FT_Pos ady, FT_Int bchar, FT_Int achar ) { FT_Error error; FT_Int bchar_index, achar_index, n_base_points; FT_Outline* base = decoder->builder.base; FT_Vector left_bearing, advance; /* seac weirdness */ adx += decoder->builder.left_bearing.x; /* `glyph_names' is set to 0 for CID fonts which do not */ /* include an encoding. How can we deal with these? */ if ( decoder->glyph_names == 0 ) { FT_ERROR(( "t1operator_seac:" )); FT_ERROR(( " glyph names table not available in this font!\n" )); return PSaux_Err_Syntax_Error; } bchar_index = t1_lookup_glyph_by_stdcharcode( decoder, bchar ); achar_index = t1_lookup_glyph_by_stdcharcode( decoder, achar ); if ( bchar_index < 0 || achar_index < 0 ) { FT_ERROR(( "t1operator_seac:" )); FT_ERROR(( " invalid seac character code arguments\n" )); return PSaux_Err_Syntax_Error; } /* if we are trying to load a composite glyph, do not load the */ /* accent character and return the array of subglyphs. */ if ( decoder->builder.no_recurse ) { FT_GlyphSlot glyph = (FT_GlyphSlot)decoder->builder.glyph; FT_GlyphLoader* loader = glyph->internal->loader; FT_SubGlyph* subg; /* reallocate subglyph array if necessary */ error = FT_GlyphLoader_Check_Subglyphs( loader, 2 ); if ( error ) goto Exit; subg = loader->current.subglyphs; /* subglyph 0 = base character */ subg->index = bchar_index; subg->flags = FT_SUBGLYPH_FLAG_ARGS_ARE_XY_VALUES | FT_SUBGLYPH_FLAG_USE_MY_METRICS; subg->arg1 = 0; subg->arg2 = 0; subg++; /* subglyph 1 = accent character */ subg->index = achar_index; subg->flags = FT_SUBGLYPH_FLAG_ARGS_ARE_XY_VALUES; subg->arg1 = adx - asb; subg->arg2 = ady; /* set up remaining glyph fields */ glyph->num_subglyphs = 2; glyph->subglyphs = loader->base.subglyphs; glyph->format = ft_glyph_format_composite; loader->current.num_subglyphs = 2; } /* First load `bchar' in builder */ /* now load the unscaled outline */ FT_GlyphLoader_Prepare( decoder->builder.loader ); /* prepare loader */ error = T1_Decoder_Parse_Glyph( decoder, bchar_index ); if ( error ) goto Exit; n_base_points = base->n_points; /* save the left bearing and width of the base character */ /* as they will be erased by the next load. */ left_bearing = decoder->builder.left_bearing; advance = decoder->builder.advance; decoder->builder.left_bearing.x = 0; decoder->builder.left_bearing.y = 0; /* Now load `achar' on top of */ /* the base outline */ error = T1_Decoder_Parse_Glyph( decoder, achar_index ); if ( error ) goto Exit; /* restore the left side bearing and */ /* advance width of the base character */ decoder->builder.left_bearing = left_bearing; decoder->builder.advance = advance; /* Finally, move the accent */ if ( decoder->builder.load_points ) { FT_Outline dummy; dummy.n_points = (short)( base->n_points - n_base_points ); dummy.points = base->points + n_base_points; FT_Outline_Translate( &dummy, adx - asb, ady ); } Exit: return error; } /*************************************************************************/ /* */ /* <Function> */ /* T1_Decoder_Parse_Charstrings */ /* */ /* <Description> */ /* Parses a given Type 1 charstrings program. */ /* */ /* <Input> */ /* decoder :: The current Type 1 decoder. */ /* */ /* charstring_base :: The base address of the charstring stream. */ /* */ /* charstring_len :: The length in bytes of the charstring stream. */ /* */ /* <Return> */ /* FreeType error code. 0 means success. */ /* */ FT_LOCAL_DEF FT_Error T1_Decoder_Parse_Charstrings( T1_Decoder* decoder, FT_Byte* charstring_base, FT_UInt charstring_len ) { FT_Error error; T1_Decoder_Zone* zone; FT_Byte* ip; FT_Byte* limit; T1_Builder* builder = &decoder->builder; FT_Pos x, y; /* we don't want to touch the source code -- use macro trick */ #define start_point T1_Builder_Start_Point #define check_points T1_Builder_Check_Points #define add_point T1_Builder_Add_Point #define add_point1 T1_Builder_Add_Point1 #define add_contour T1_Builder_Add_Contour #define close_contour T1_Builder_Close_Contour /* First of all, initialize the decoder */ decoder->top = decoder->stack; decoder->zone = decoder->zones; zone = decoder->zones; builder->path_begun = 0; zone->base = charstring_base; limit = zone->limit = charstring_base + charstring_len; ip = zone->cursor = zone->base; error = PSaux_Err_Ok; x = builder->pos_x; y = builder->pos_y; /* now, execute loop */ while ( ip < limit ) { FT_Long* top = decoder->top; T1_Operator op = op_none; FT_Long value = 0; /*********************************************************************/ /* */ /* Decode operator or operand */ /* */ /* */ /* first of all, decompress operator or value */ switch ( *ip++ ) { case 1: op = op_hstem; break; case 3: op = op_vstem; break; case 4: op = op_vmoveto; break; case 5: op = op_rlineto; break; case 6: op = op_hlineto; break; case 7: op = op_vlineto; break; case 8: op = op_rrcurveto; break; case 9: op = op_closepath; break; case 10: op = op_callsubr; break; case 11: op = op_return; break; case 13: op = op_hsbw; break; case 14: op = op_endchar; break; case 21: op = op_rmoveto; break; case 22: op = op_hmoveto; break; case 30: op = op_vhcurveto; break; case 31: op = op_hvcurveto; break; case 12: if ( ip > limit ) { FT_ERROR(( "T1_Decoder_Parse_CharStrings: " "invalid escape (12+EOF)\n" )); goto Syntax_Error; } switch ( *ip++ ) { case 0: op = op_dotsection; break; case 1: op = op_vstem3; break; case 2: op = op_hstem3; break; case 6: op = op_seac; break; case 7: op = op_sbw; break; case 12: op = op_div; break; case 16: op = op_callothersubr; break; case 17: op = op_pop; break; case 33: op = op_setcurrentpoint; break; default: FT_ERROR(( "T1_Decoder_Parse_CharStrings: " "invalid escape (12+%d)\n", ip[-1] )); goto Syntax_Error; } break; case 255: /* four bytes integer */ if ( ip + 4 > limit ) { FT_ERROR(( "T1_Decoder_Parse_CharStrings: " "unexpected EOF in integer\n" )); goto Syntax_Error; } value = (FT_Int32)( ((FT_Long)ip[0] << 24) | ((FT_Long)ip[1] << 16) | ((FT_Long)ip[2] << 8 ) | ip[3] ); ip += 4; break; default: if ( ip[-1] >= 32 ) { if ( ip[-1] < 247 ) value = (FT_Long)ip[-1] - 139; else { if ( ++ip > limit ) { FT_ERROR(( "T1_Decoder_Parse_CharStrings: " )); FT_ERROR(( "unexpected EOF in integer\n" )); goto Syntax_Error; } if ( ip[-2] < 251 ) value = ( ( (FT_Long)ip[-2] - 247 ) << 8 ) + ip[-1] + 108; else value = -( ( ( (FT_Long)ip[-2] - 251 ) << 8 ) + ip[-1] + 108 ); } } else { FT_ERROR(( "T1_Decoder_Parse_CharStrings: " "invalid byte (%d)\n", ip[-1] )); goto Syntax_Error; } } /*********************************************************************/ /* */ /* Push value on stack, or process operator */ /* */ /* */ if ( op == op_none ) { if ( top - decoder->stack >= T1_MAX_CHARSTRINGS_OPERANDS ) { FT_ERROR(( "T1_Decoder_Parse_CharStrings: stack overflow!\n" )); goto Syntax_Error; } FT_TRACE4(( " %ld", value )); *top++ = value; decoder->top = top; } else if ( op == op_callothersubr ) /* callothersubr */ { FT_TRACE4(( " callothersubr" )); if ( top - decoder->stack < 2 ) goto Stack_Underflow; top -= 2; switch ( top[1] ) { case 1: /* start flex feature */ if ( top[0] != 0 ) goto Unexpected_OtherSubr; decoder->flex_state = 1; decoder->num_flex_vectors = 0; if ( start_point( builder, x, y ) || check_points( builder, 6 ) ) goto Memory_Error; break; case 2: /* add flex vectors */ { FT_Int index; if ( top[0] != 0 ) goto Unexpected_OtherSubr; /* note that we should not add a point for index 0; */ /* this will move our current position to the flex */ /* point without adding any point to the outline */ index = decoder->num_flex_vectors++; if ( index > 0 && index < 7 ) add_point( builder, x, y, (FT_Byte)( index == 3 || index == 6 ) ); } break; case 0: /* end flex feature */ if ( top[0] != 3 ) goto Unexpected_OtherSubr; if ( decoder->flex_state == 0 || decoder->num_flex_vectors != 7 ) { FT_ERROR(( "T1_Decoder_Parse_CharStrings: " "unexpected flex end\n" )); goto Syntax_Error; } /* now consume the remaining `pop pop setcurpoint' */ if ( ip + 6 > limit || ip[0] != 12 || ip[1] != 17 || /* pop */ ip[2] != 12 || ip[3] != 17 || /* pop */ ip[4] != 12 || ip[5] != 33 ) /* setcurpoint */ { FT_ERROR(( "T1_Decoder_Parse_CharStrings: " "invalid flex charstring\n" )); goto Syntax_Error; } ip += 6; decoder->flex_state = 0; break; case 3: /* change hints */ if ( top[0] != 1 ) goto Unexpected_OtherSubr; /* eat the following `pop' */ if ( ip + 2 > limit ) { FT_ERROR(( "T1_Decoder_Parse_CharStrings: " "invalid escape (12+%d)\n", ip[-1] )); goto Syntax_Error; } if ( ip[0] != 12 || ip[1] != 17 ) { FT_ERROR(( "T1_Decoder_Parse_CharStrings: " )); FT_ERROR(( "`pop' expected, found (%d %d)\n", ip[0], ip[1] )); goto Syntax_Error; } ip += 2; break; case 12: case 13: /* counter control hints, clear stack */ top = decoder->stack; break; case 14: case 15: case 16: case 17: case 18: /* multiple masters */ { T1_Blend* blend = decoder->blend; FT_UInt num_points, nn, mm; FT_Long* delta; FT_Long* values; if ( !blend ) { FT_ERROR(( "T1_Decoder_Parse_CharStrings: " )); FT_ERROR(( "unexpected multiple masters operator!\n" )); goto Syntax_Error; } num_points = top[1] - 13 + ( top[1] == 18 ); if ( top[0] != (FT_Int)( num_points * blend->num_designs ) ) { FT_ERROR(( "T1_Decoder_Parse_CharStrings: " )); FT_ERROR(( "incorrect number of mm arguments\n" )); goto Syntax_Error; } top -= blend->num_designs*num_points; if ( top < decoder->stack ) goto Stack_Underflow; /* we want to compute: */ /* */ /* a0*w0 + a1*w1 + ... + ak*wk */ /* */ /* but we only have the a0, a1-a0, a2-a0, .. ak-a0 */ /* however, given that w0 + w1 + ... + wk == 1, we can */ /* rewrite it easily as: */ /* */ /* a0 + (a1-a0)*w1 + (a2-a0)*w2 + .. + (ak-a0)*wk */ /* */ /* where k == num_designs-1 */ /* */ /* I guess that's why it's written in this `compact' */ /* form. */ /* */ delta = top + num_points; values = top; for ( nn = 0; nn < num_points; nn++ ) { FT_Int tmp = values[0]; for ( mm = 1; mm < blend->num_designs; mm++ ) tmp += FT_MulFix( *delta++, blend->weight_vector[mm] ); *values++ = tmp; } /* note that `top' will be incremented later by calls to `pop' */ break; } default: Unexpected_OtherSubr: FT_ERROR(( "T1_Decoder_Parse_CharStrings: " "invalid othersubr [%d %d]!\n", top[0], top[1] )); goto Syntax_Error; } decoder->top = top; } else /* general operator */ { FT_Int num_args = t1_args_count[op]; if ( top - decoder->stack < num_args ) goto Stack_Underflow; top -= num_args; switch ( op ) { case op_endchar: FT_TRACE4(( " endchar" )); close_contour( builder ); /* add current outline to the glyph slot */ FT_GlyphLoader_Add( builder->loader ); /* return now! */ FT_TRACE4(( "\n\n" )); return PSaux_Err_Ok; case op_hsbw: FT_TRACE4(( " hsbw" )); builder->left_bearing.x += top[0]; builder->advance.x = top[1]; builder->advance.y = 0; builder->last.x = x = top[0]; builder->last.y = y = 0; /* the `metrics_only' indicates that we only want to compute */ /* the glyph's metrics (lsb + advance width), not load the */ /* rest of it; so exit immediately */ if ( builder->metrics_only ) return PSaux_Err_Ok; break; case op_seac: /* return immediately after the processing */ return t1operator_seac( decoder, top[0], top[1], top[2], top[3], top[4] ); case op_sbw: FT_TRACE4(( " sbw" )); builder->left_bearing.x += top[0]; builder->left_bearing.y += top[1]; builder->advance.x = top[2]; builder->advance.y = top[3]; builder->last.x = x = top[0]; builder->last.y = y = top[1]; /* the `metrics_only' indicates that we only want to compute */ /* the glyph's metrics (lsb + advance width), not load the */ /* rest of it; so exit immediately */ if ( builder->metrics_only ) return PSaux_Err_Ok; break; case op_closepath: FT_TRACE4(( " closepath" )); close_contour( builder ); builder->path_begun = 0; break; case op_hlineto: FT_TRACE4(( " hlineto" )); if ( start_point( builder, x, y ) ) goto Memory_Error; x += top[0]; goto Add_Line; case op_hmoveto: FT_TRACE4(( " hmoveto" )); x += top[0]; if ( !decoder->flex_state ) builder->path_begun = 0; break; case op_hvcurveto: FT_TRACE4(( " hvcurveto" )); if ( start_point( builder, x, y ) || check_points( builder, 3 ) ) goto Memory_Error; x += top[0]; add_point( builder, x, y, 0 ); x += top[1]; y += top[2]; add_point( builder, x, y, 0 ); y += top[3]; add_point( builder, x, y, 1 ); break; case op_rlineto: FT_TRACE4(( " rlineto" )); if ( start_point( builder, x, y ) ) goto Memory_Error; x += top[0]; y += top[1]; Add_Line: if ( add_point1( builder, x, y ) ) goto Memory_Error; break; case op_rmoveto: FT_TRACE4(( " rmoveto" )); x += top[0]; y += top[1]; if ( !decoder->flex_state ) builder->path_begun = 0; break; case op_rrcurveto: FT_TRACE4(( " rcurveto" )); if ( start_point( builder, x, y ) || check_points( builder, 3 ) ) goto Memory_Error; x += top[0]; y += top[1]; add_point( builder, x, y, 0 ); x += top[2]; y += top[3]; add_point( builder, x, y, 0 ); x += top[4]; y += top[5]; add_point( builder, x, y, 1 ); break; case op_vhcurveto: FT_TRACE4(( " vhcurveto" )); if ( start_point( builder, x, y ) || check_points( builder, 3 ) ) goto Memory_Error; y += top[0]; add_point( builder, x, y, 0 ); x += top[1]; y += top[2]; add_point( builder, x, y, 0 ); x += top[3]; add_point( builder, x, y, 1 ); break; case op_vlineto: FT_TRACE4(( " vlineto" )); if ( start_point( builder, x, y ) ) goto Memory_Error; y += top[0]; goto Add_Line; case op_vmoveto: FT_TRACE4(( " vmoveto" )); y += top[0]; if ( !decoder->flex_state ) builder->path_begun = 0; break; case op_div: FT_TRACE4(( " div" )); if ( top[1] ) { *top = top[0] / top[1]; ++top; } else { FT_ERROR(( "T1_Decoder_Parse_CharStrings: division by 0\n" )); goto Syntax_Error; } break; case op_callsubr: { FT_Int index; FT_TRACE4(( " callsubr" )); index = top[0]; if ( index < 0 || index >= (FT_Int)decoder->num_subrs ) { FT_ERROR(( "T1_Decoder_Parse_CharStrings: " "invalid subrs index\n" )); goto Syntax_Error; } if ( zone - decoder->zones >= T1_MAX_SUBRS_CALLS ) { FT_ERROR(( "T1_Decoder_Parse_CharStrings: " "too many nested subrs\n" )); goto Syntax_Error; } zone->cursor = ip; /* save current instruction pointer */ zone++; /* The Type 1 driver stores subroutines without the seed bytes. */ /* The CID driver stores subroutines with seed bytes. This */ /* case is taken care of when decoder->subrs_len == 0. */ zone->base = decoder->subrs[index]; if ( decoder->subrs_len ) zone->limit = zone->base + decoder->subrs_len[index]; else { /* We are using subroutines from a CID font. We must adjust */ /* for the seed bytes. */ zone->base += ( decoder->lenIV >= 0 ? decoder->lenIV : 0 ); zone->limit = decoder->subrs[index + 1]; } zone->cursor = zone->base; if ( !zone->base ) { FT_ERROR(( "T1_Decoder_Parse_CharStrings: " "invoking empty subrs!\n" )); goto Syntax_Error; } decoder->zone = zone; ip = zone->base; limit = zone->limit; break; } case op_pop: FT_TRACE4(( " pop" )); /* theoretically, the arguments are already on the stack */ top++; break; case op_return: FT_TRACE4(( " return" )); if ( zone <= decoder->zones ) { FT_ERROR(( "T1_Decoder_Parse_CharStrings: unexpected return\n" )); goto Syntax_Error; } zone--; ip = zone->cursor; limit = zone->limit; decoder->zone = zone; break; case op_dotsection: FT_TRACE4(( " dotsection" )); break; case op_hstem: FT_TRACE4(( " hstem" )); break; case op_hstem3: FT_TRACE4(( " hstem3" )); break; case op_vstem: FT_TRACE4(( " vstem" )); break; case op_vstem3: FT_TRACE4(( " vstem3" )); break; case op_setcurrentpoint: FT_TRACE4(( " setcurrentpoint" )); FT_ERROR(( "T1_Decoder_Parse_CharStrings: " )); FT_ERROR(( "unexpected `setcurrentpoint'\n" )); goto Syntax_Error; default: FT_ERROR(( "T1_Decoder_Parse_CharStrings: " "unhandled opcode %d\n", op )); goto Syntax_Error; } decoder->top = top; } /* general operator processing */ } /* while ip < limit */ FT_TRACE4(( "..end..\n\n" )); return error; Syntax_Error: return PSaux_Err_Syntax_Error; Stack_Underflow: return PSaux_Err_Stack_Underflow; Memory_Error: return builder->error; } FT_LOCAL_DEF FT_Error T1_Decoder_Parse_Glyph( T1_Decoder* decoder, FT_UInt glyph ) { return decoder->parse_callback( decoder, glyph ); } FT_LOCAL_DEF FT_Error T1_Decoder_Init( T1_Decoder* decoder, FT_Face face, FT_Size size, FT_GlyphSlot slot, FT_Byte** glyph_names, T1_Blend* blend, T1_Decoder_Callback parse_callback ) { MEM_Set( decoder, 0, sizeof ( *decoder ) ); /* retrieve PSNames interface from list of current modules */ { PSNames_Interface* psnames = 0; psnames = (PSNames_Interface*)FT_Get_Module_Interface( FT_FACE_LIBRARY(face), "psnames" ); if ( !psnames ) { FT_ERROR(( "T1_Decoder_Init: " )); FT_ERROR(( "the `psnames' module is not available\n" )); return PSaux_Err_Unimplemented_Feature; } decoder->psnames = psnames; } T1_Builder_Init( &decoder->builder, face, size, slot ); decoder->num_glyphs = face->num_glyphs; decoder->glyph_names = glyph_names; decoder->blend = blend; decoder->parse_callback = parse_callback; decoder->funcs = t1_decoder_funcs; return 0; } FT_LOCAL_DEF void T1_Decoder_Done( T1_Decoder* decoder ) { T1_Builder_Done( &decoder->builder ); } /* END */