ref: d20dc3928b9d3ee075106b7684dab6111d6a5899
dir: /src/truetype/ttdriver.c/
/**************************************************************************** * * ttdriver.c * * TrueType font driver implementation (body). * * Copyright 1996-2018 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_INTERNAL_STREAM_H #include FT_INTERNAL_SFNT_H #include FT_SERVICE_FONT_FORMAT_H #ifdef TT_CONFIG_OPTION_GX_VAR_SUPPORT #include FT_MULTIPLE_MASTERS_H #include FT_SERVICE_MULTIPLE_MASTERS_H #include FT_SERVICE_METRICS_VARIATIONS_H #endif #include FT_SERVICE_TRUETYPE_ENGINE_H #include FT_SERVICE_TRUETYPE_GLYF_H #include FT_SERVICE_PROPERTIES_H #include FT_DRIVER_H #include "ttdriver.h" #include "ttgload.h" #include "ttpload.h" #ifdef TT_CONFIG_OPTION_GX_VAR_SUPPORT #include "ttgxvar.h" #endif #include "tterrors.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 ttdriver /* * PROPERTY SERVICE * */ static FT_Error tt_property_set( FT_Module module, /* TT_Driver */ const char* property_name, const void* value, FT_Bool value_is_string ) { FT_Error error = FT_Err_Ok; TT_Driver driver = (TT_Driver)module; #ifndef FT_CONFIG_OPTION_ENVIRONMENT_PROPERTIES FT_UNUSED( value_is_string ); #endif if ( !ft_strcmp( property_name, "interpreter-version" ) ) { FT_UInt interpreter_version; #ifdef FT_CONFIG_OPTION_ENVIRONMENT_PROPERTIES if ( value_is_string ) { const char* s = (const char*)value; interpreter_version = (FT_UInt)ft_strtol( s, NULL, 10 ); } else #endif { FT_UInt* iv = (FT_UInt*)value; interpreter_version = *iv; } if ( interpreter_version == TT_INTERPRETER_VERSION_35 #ifdef TT_SUPPORT_SUBPIXEL_HINTING_INFINALITY || interpreter_version == TT_INTERPRETER_VERSION_38 #endif #ifdef TT_SUPPORT_SUBPIXEL_HINTING_MINIMAL || interpreter_version == TT_INTERPRETER_VERSION_40 #endif ) driver->interpreter_version = interpreter_version; else error = FT_ERR( Unimplemented_Feature ); return error; } FT_TRACE0(( "tt_property_set: missing property `%s'\n", property_name )); return FT_THROW( Missing_Property ); } static FT_Error tt_property_get( FT_Module module, /* TT_Driver */ const char* property_name, const void* value ) { FT_Error error = FT_Err_Ok; TT_Driver driver = (TT_Driver)module; FT_UInt interpreter_version = driver->interpreter_version; if ( !ft_strcmp( property_name, "interpreter-version" ) ) { FT_UInt* val = (FT_UInt*)value; *val = interpreter_version; return error; } FT_TRACE0(( "tt_property_get: missing property `%s'\n", property_name )); return FT_THROW( Missing_Property ); } FT_DEFINE_SERVICE_PROPERTIESREC( tt_service_properties, (FT_Properties_SetFunc)tt_property_set, /* set_property */ (FT_Properties_GetFunc)tt_property_get /* get_property */ ) /*************************************************************************/ /*************************************************************************/ /*************************************************************************/ /**** ****/ /**** ****/ /**** F A C E S ****/ /**** ****/ /**** ****/ /*************************************************************************/ /*************************************************************************/ /*************************************************************************/ /************************************************************************** * * @Function: * tt_get_kerning * * @Description: * A driver method used to return the kerning vector between two * glyphs of the same face. * * @Input: * face :: * A handle to the source face object. * * left_glyph :: * The index of the left glyph in the kern pair. * * right_glyph :: * The index of the right glyph in the kern pair. * * @Output: * kerning :: * The kerning vector. This is in font units for * scalable formats, and in pixels for fixed-sizes * formats. * * @Return: * FreeType error code. 0 means success. * * @Note: * Only horizontal layouts (left-to-right & right-to-left) are * supported by this function. Other layouts, or more sophisticated * kernings, are out of scope of this method (the basic driver * interface is meant to be simple). * * They can be implemented by format-specific interfaces. */ static FT_Error tt_get_kerning( FT_Face ttface, /* TT_Face */ FT_UInt left_glyph, FT_UInt right_glyph, FT_Vector* kerning ) { TT_Face face = (TT_Face)ttface; SFNT_Service sfnt = (SFNT_Service)face->sfnt; kerning->x = 0; kerning->y = 0; if ( sfnt ) kerning->x = sfnt->get_kerning( face, left_glyph, right_glyph ); return 0; } static FT_Error tt_get_advances( FT_Face ttface, FT_UInt start, FT_UInt count, FT_Int32 flags, FT_Fixed *advances ) { FT_UInt nn; TT_Face face = (TT_Face)ttface; /* XXX: TODO: check for sbits */ if ( flags & FT_LOAD_VERTICAL_LAYOUT ) { #ifdef TT_CONFIG_OPTION_GX_VAR_SUPPORT /* no fast retrieval for blended MM fonts without VVAR table */ if ( ( FT_IS_NAMED_INSTANCE( ttface ) || FT_IS_VARIATION( ttface ) ) && !( face->variation_support & TT_FACE_FLAG_VAR_VADVANCE ) ) return FT_THROW( Unimplemented_Feature ); #endif for ( nn = 0; nn < count; nn++ ) { FT_Short tsb; FT_UShort ah; /* since we don't need `tsb', we use zero for `yMax' parameter */ TT_Get_VMetrics( face, start + nn, 0, &tsb, &ah ); advances[nn] = ah; } } else { #ifdef TT_CONFIG_OPTION_GX_VAR_SUPPORT /* no fast retrieval for blended MM fonts without HVAR table */ if ( ( FT_IS_NAMED_INSTANCE( ttface ) || FT_IS_VARIATION( ttface ) ) && !( face->variation_support & TT_FACE_FLAG_VAR_HADVANCE ) ) return FT_THROW( Unimplemented_Feature ); #endif for ( nn = 0; nn < count; nn++ ) { FT_Short lsb; FT_UShort aw; TT_Get_HMetrics( face, start + nn, &lsb, &aw ); advances[nn] = aw; } } return FT_Err_Ok; } /*************************************************************************/ /*************************************************************************/ /*************************************************************************/ /**** ****/ /**** ****/ /**** S I Z E S ****/ /**** ****/ /**** ****/ /*************************************************************************/ /*************************************************************************/ /*************************************************************************/ #ifdef TT_CONFIG_OPTION_EMBEDDED_BITMAPS static FT_Error tt_size_select( FT_Size size, FT_ULong strike_index ) { TT_Face ttface = (TT_Face)size->face; TT_Size ttsize = (TT_Size)size; FT_Error error = FT_Err_Ok; ttsize->strike_index = strike_index; if ( FT_IS_SCALABLE( size->face ) ) { /* use the scaled metrics, even when tt_size_reset fails */ FT_Select_Metrics( size->face, strike_index ); tt_size_reset( ttsize, 0 ); /* ignore return value */ } else { SFNT_Service sfnt = (SFNT_Service)ttface->sfnt; FT_Size_Metrics* size_metrics = &size->metrics; error = sfnt->load_strike_metrics( ttface, strike_index, size_metrics ); if ( error ) ttsize->strike_index = 0xFFFFFFFFUL; } return error; } #endif /* TT_CONFIG_OPTION_EMBEDDED_BITMAPS */ static FT_Error tt_size_request( FT_Size size, FT_Size_Request req ) { TT_Size ttsize = (TT_Size)size; FT_Error error = FT_Err_Ok; #ifdef TT_CONFIG_OPTION_EMBEDDED_BITMAPS if ( FT_HAS_FIXED_SIZES( size->face ) ) { TT_Face ttface = (TT_Face)size->face; SFNT_Service sfnt = (SFNT_Service)ttface->sfnt; FT_ULong strike_index; error = sfnt->set_sbit_strike( ttface, req, &strike_index ); if ( error ) ttsize->strike_index = 0xFFFFFFFFUL; else return tt_size_select( size, strike_index ); } #endif /* TT_CONFIG_OPTION_EMBEDDED_BITMAPS */ FT_Request_Metrics( size->face, req ); if ( FT_IS_SCALABLE( size->face ) ) { error = tt_size_reset( ttsize, 0 ); #ifdef TT_USE_BYTECODE_INTERPRETER /* for the `MPS' bytecode instruction we need the point size */ if ( !error ) { FT_UInt resolution = ttsize->metrics->x_ppem > ttsize->metrics->y_ppem ? req->horiResolution : req->vertResolution; /* if we don't have a resolution value, assume 72dpi */ if ( req->type == FT_SIZE_REQUEST_TYPE_SCALES || !resolution ) resolution = 72; ttsize->point_size = FT_MulDiv( ttsize->ttmetrics.ppem, 64 * 72, resolution ); } #endif } return error; } /************************************************************************** * * @Function: * tt_glyph_load * * @Description: * A driver method used to load a glyph within a given glyph slot. * * @Input: * slot :: * A handle to the target slot object where the glyph * will be loaded. * * size :: * A handle to the source face size at which the glyph * must be scaled, loaded, etc. * * glyph_index :: * The index of the glyph in the font file. * * load_flags :: * A flag indicating what to load for this glyph. The * FT_LOAD_XXX constants can be used to control the * glyph loading process (e.g., whether the outline * should be scaled, whether to load bitmaps or not, * whether to hint the outline, etc). * * @Return: * FreeType error code. 0 means success. */ static FT_Error tt_glyph_load( FT_GlyphSlot ttslot, /* TT_GlyphSlot */ FT_Size ttsize, /* TT_Size */ FT_UInt glyph_index, FT_Int32 load_flags ) { TT_GlyphSlot slot = (TT_GlyphSlot)ttslot; TT_Size size = (TT_Size)ttsize; FT_Face face = ttslot->face; FT_Error error; if ( !slot ) return FT_THROW( Invalid_Slot_Handle ); if ( !size ) return FT_THROW( Invalid_Size_Handle ); if ( !face ) return FT_THROW( Invalid_Face_Handle ); #ifdef FT_CONFIG_OPTION_INCREMENTAL if ( glyph_index >= (FT_UInt)face->num_glyphs && !face->internal->incremental_interface ) #else if ( glyph_index >= (FT_UInt)face->num_glyphs ) #endif return FT_THROW( Invalid_Argument ); if ( load_flags & FT_LOAD_NO_HINTING ) { /* both FT_LOAD_NO_HINTING and FT_LOAD_NO_AUTOHINT */ /* are necessary to disable hinting for tricky fonts */ if ( FT_IS_TRICKY( face ) ) load_flags &= ~FT_LOAD_NO_HINTING; if ( load_flags & FT_LOAD_NO_AUTOHINT ) load_flags |= FT_LOAD_NO_HINTING; } if ( load_flags & ( FT_LOAD_NO_RECURSE | FT_LOAD_NO_SCALE ) ) { load_flags |= FT_LOAD_NO_BITMAP | FT_LOAD_NO_SCALE; if ( !FT_IS_TRICKY( face ) ) load_flags |= FT_LOAD_NO_HINTING; } /* use hinted metrics only if we load a glyph with hinting */ size->metrics = ( load_flags & FT_LOAD_NO_HINTING ) ? &ttsize->metrics : &size->hinted_metrics; /* now fill in the glyph slot with outline/bitmap/layered */ error = TT_Load_Glyph( size, slot, glyph_index, load_flags ); /* force drop-out mode to 2 - irrelevant now */ /* slot->outline.dropout_mode = 2; */ return error; } /*************************************************************************/ /*************************************************************************/ /*************************************************************************/ /**** ****/ /**** ****/ /**** D R I V E R I N T E R F A C E ****/ /**** ****/ /**** ****/ /*************************************************************************/ /*************************************************************************/ /*************************************************************************/ #ifdef TT_CONFIG_OPTION_GX_VAR_SUPPORT FT_DEFINE_SERVICE_MULTIMASTERSREC( tt_service_gx_multi_masters, (FT_Get_MM_Func) NULL, /* get_mm */ (FT_Set_MM_Design_Func) NULL, /* set_mm_design */ (FT_Set_MM_Blend_Func) TT_Set_MM_Blend, /* set_mm_blend */ (FT_Get_MM_Blend_Func) TT_Get_MM_Blend, /* get_mm_blend */ (FT_Get_MM_Var_Func) TT_Get_MM_Var, /* get_mm_var */ (FT_Set_Var_Design_Func)TT_Set_Var_Design, /* set_var_design */ (FT_Get_Var_Design_Func)TT_Get_Var_Design, /* get_var_design */ (FT_Set_Instance_Func) TT_Set_Named_Instance, /* set_instance */ (FT_Get_Var_Blend_Func) tt_get_var_blend, /* get_var_blend */ (FT_Done_Blend_Func) tt_done_blend /* done_blend */ ) FT_DEFINE_SERVICE_METRICSVARIATIONSREC( tt_service_metrics_variations, (FT_HAdvance_Adjust_Func)tt_hadvance_adjust, /* hadvance_adjust */ (FT_LSB_Adjust_Func) NULL, /* lsb_adjust */ (FT_RSB_Adjust_Func) NULL, /* rsb_adjust */ (FT_VAdvance_Adjust_Func)tt_vadvance_adjust, /* vadvance_adjust */ (FT_TSB_Adjust_Func) NULL, /* tsb_adjust */ (FT_BSB_Adjust_Func) NULL, /* bsb_adjust */ (FT_VOrg_Adjust_Func) NULL, /* vorg_adjust */ (FT_Metrics_Adjust_Func) tt_apply_mvar /* metrics_adjust */ ) #endif /* TT_CONFIG_OPTION_GX_VAR_SUPPORT */ static const FT_Service_TrueTypeEngineRec tt_service_truetype_engine = { #ifdef TT_USE_BYTECODE_INTERPRETER FT_TRUETYPE_ENGINE_TYPE_PATENTED #else /* !TT_USE_BYTECODE_INTERPRETER */ FT_TRUETYPE_ENGINE_TYPE_NONE #endif /* TT_USE_BYTECODE_INTERPRETER */ }; FT_DEFINE_SERVICE_TTGLYFREC( tt_service_truetype_glyf, (TT_Glyf_GetLocationFunc)tt_face_get_location /* get_location */ ) #ifdef TT_CONFIG_OPTION_GX_VAR_SUPPORT FT_DEFINE_SERVICEDESCREC6( tt_services, FT_SERVICE_ID_FONT_FORMAT, FT_FONT_FORMAT_TRUETYPE, FT_SERVICE_ID_MULTI_MASTERS, &tt_service_gx_multi_masters, FT_SERVICE_ID_METRICS_VARIATIONS, &tt_service_metrics_variations, FT_SERVICE_ID_TRUETYPE_ENGINE, &tt_service_truetype_engine, FT_SERVICE_ID_TT_GLYF, &tt_service_truetype_glyf, FT_SERVICE_ID_PROPERTIES, &tt_service_properties ) #else FT_DEFINE_SERVICEDESCREC4( tt_services, FT_SERVICE_ID_FONT_FORMAT, FT_FONT_FORMAT_TRUETYPE, FT_SERVICE_ID_TRUETYPE_ENGINE, &tt_service_truetype_engine, FT_SERVICE_ID_TT_GLYF, &tt_service_truetype_glyf, FT_SERVICE_ID_PROPERTIES, &tt_service_properties ) #endif FT_CALLBACK_DEF( FT_Module_Interface ) tt_get_interface( FT_Module driver, /* TT_Driver */ const char* tt_interface ) { FT_Library library; FT_Module_Interface result; FT_Module sfntd; SFNT_Service sfnt; result = ft_service_list_lookup( tt_services, tt_interface ); if ( result ) return result; if ( !driver ) return NULL; library = driver->library; if ( !library ) return NULL; /* only return the default interface from the SFNT module */ sfntd = FT_Get_Module( library, "sfnt" ); if ( sfntd ) { sfnt = (SFNT_Service)( sfntd->clazz->module_interface ); if ( sfnt ) return sfnt->get_interface( driver, tt_interface ); } return 0; } /* The FT_DriverInterface structure is defined in ftdriver.h. */ #ifdef TT_USE_BYTECODE_INTERPRETER #define TT_HINTER_FLAG FT_MODULE_DRIVER_HAS_HINTER #else #define TT_HINTER_FLAG 0 #endif #ifdef TT_CONFIG_OPTION_EMBEDDED_BITMAPS #define TT_SIZE_SELECT tt_size_select #else #define TT_SIZE_SELECT 0 #endif FT_DEFINE_DRIVER( tt_driver_class, FT_MODULE_FONT_DRIVER | FT_MODULE_DRIVER_SCALABLE | TT_HINTER_FLAG, sizeof ( TT_DriverRec ), "truetype", /* driver name */ 0x10000L, /* driver version == 1.0 */ 0x20000L, /* driver requires FreeType 2.0 or above */ NULL, /* module-specific interface */ tt_driver_init, /* FT_Module_Constructor module_init */ tt_driver_done, /* FT_Module_Destructor module_done */ tt_get_interface, /* FT_Module_Requester get_interface */ sizeof ( TT_FaceRec ), sizeof ( TT_SizeRec ), sizeof ( FT_GlyphSlotRec ), tt_face_init, /* FT_Face_InitFunc init_face */ tt_face_done, /* FT_Face_DoneFunc done_face */ tt_size_init, /* FT_Size_InitFunc init_size */ tt_size_done, /* FT_Size_DoneFunc done_size */ tt_slot_init, /* FT_Slot_InitFunc init_slot */ NULL, /* FT_Slot_DoneFunc done_slot */ tt_glyph_load, /* FT_Slot_LoadFunc load_glyph */ tt_get_kerning, /* FT_Face_GetKerningFunc get_kerning */ NULL, /* FT_Face_AttachFunc attach_file */ tt_get_advances, /* FT_Face_GetAdvancesFunc get_advances */ tt_size_request, /* FT_Size_RequestFunc request_size */ TT_SIZE_SELECT /* FT_Size_SelectFunc select_size */ ) /* END */