ref: 11975fe9f6ed92b7630698e599b936a0186d965d
dir: /src/base/ftgloadr.c/
/**************************************************************************** * * ftgloadr.c * * The FreeType glyph loader (body). * * Copyright (C) 2002-2020 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_GLYPH_LOADER_H #include FT_INTERNAL_MEMORY_H #include FT_INTERNAL_OBJECTS_H #undef FT_COMPONENT #define FT_COMPONENT gloader /*************************************************************************/ /*************************************************************************/ /*************************************************************************/ /***** *****/ /***** *****/ /***** G L Y P H L O A D E R *****/ /***** *****/ /***** *****/ /*************************************************************************/ /*************************************************************************/ /*************************************************************************/ /************************************************************************** * * The glyph loader is a simple object which is used to load a set of * glyphs easily. It is critical for the correct loading of composites. * * Ideally, one can see it as a stack of abstract `glyph' objects. * * loader.base Is really the bottom of the stack. It describes a * single glyph image made of the juxtaposition of * several glyphs (those `in the stack'). * * loader.current Describes the top of the stack, on which a new * glyph can be loaded. * * Rewind Clears the stack. * Prepare Set up `loader.current' for addition of a new glyph * image. * Add Add the `current' glyph image to the `base' one, * and prepare for another one. * * The glyph loader is now a base object. Each driver used to * re-implement it in one way or the other, which wasted code and * energy. * */ /* create a new glyph loader */ FT_BASE_DEF( FT_Error ) FT_GlyphLoader_New( FT_Memory memory, FT_GlyphLoader *aloader ) { FT_GlyphLoader loader = NULL; FT_Error error; if ( !FT_NEW( loader ) ) { loader->memory = memory; *aloader = loader; } return error; } /* rewind the glyph loader - reset counters to 0 */ FT_BASE_DEF( void ) FT_GlyphLoader_Rewind( FT_GlyphLoader loader ) { FT_GlyphLoad base = &loader->base; FT_GlyphLoad current = &loader->current; base->outline.n_points = 0; base->outline.n_contours = 0; base->num_subglyphs = 0; *current = *base; } /* reset glyph loader, free all allocated tables, */ /* and start from zero */ FT_BASE_DEF( void ) FT_GlyphLoader_Reset( FT_GlyphLoader loader ) { FT_Memory memory = loader->memory; FT_FREE( loader->base.outline.points ); FT_FREE( loader->base.outline.tags ); FT_FREE( loader->base.outline.contours ); FT_FREE( loader->base.extra_points ); FT_FREE( loader->base.subglyphs ); loader->base.extra_points2 = NULL; loader->max_points = 0; loader->max_contours = 0; loader->max_subglyphs = 0; FT_GlyphLoader_Rewind( loader ); } /* delete a glyph loader */ FT_BASE_DEF( void ) FT_GlyphLoader_Done( FT_GlyphLoader loader ) { if ( loader ) { FT_Memory memory = loader->memory; FT_GlyphLoader_Reset( loader ); FT_FREE( loader ); } } /* re-adjust the `current' outline fields */ static void FT_GlyphLoader_Adjust_Points( FT_GlyphLoader loader ) { FT_Outline* base = &loader->base.outline; FT_Outline* current = &loader->current.outline; current->points = FT_OFFSET( base->points, base->n_points ); current->tags = FT_OFFSET( base->tags, base->n_points ); current->contours = FT_OFFSET( base->contours, base->n_contours ); /* handle extra points table - if any */ if ( loader->use_extra ) { loader->current.extra_points = loader->base.extra_points + base->n_points; loader->current.extra_points2 = loader->base.extra_points2 + base->n_points; } } FT_BASE_DEF( FT_Error ) FT_GlyphLoader_CreateExtra( FT_GlyphLoader loader ) { FT_Error error; FT_Memory memory = loader->memory; if ( loader->max_points == 0 || loader->base.extra_points != NULL ) return FT_Err_Ok; if ( !FT_NEW_ARRAY( loader->base.extra_points, 2 * loader->max_points ) ) { loader->use_extra = 1; loader->base.extra_points2 = loader->base.extra_points + loader->max_points; FT_GlyphLoader_Adjust_Points( loader ); } return error; } /* re-adjust the `current' subglyphs field */ static void FT_GlyphLoader_Adjust_Subglyphs( FT_GlyphLoader loader ) { FT_GlyphLoad base = &loader->base; FT_GlyphLoad current = &loader->current; current->subglyphs = FT_OFFSET( base->subglyphs, base->num_subglyphs ); } /* Ensure that we can add `n_points' and `n_contours' to our glyph. */ /* This function reallocates its outline tables if necessary. Note that */ /* it DOESN'T change the number of points within the loader! */ /* */ FT_BASE_DEF( FT_Error ) FT_GlyphLoader_CheckPoints( FT_GlyphLoader loader, FT_UInt n_points, FT_UInt n_contours ) { FT_Memory memory = loader->memory; FT_Error error = FT_Err_Ok; FT_Outline* base = &loader->base.outline; FT_Outline* current = &loader->current.outline; FT_Bool adjust = 0; FT_UInt new_max, old_max; error = FT_GlyphLoader_CreateExtra( loader ); if ( error ) return error; /* check points & tags */ new_max = (FT_UInt)base->n_points + (FT_UInt)current->n_points + n_points; old_max = loader->max_points; if ( new_max > old_max ) { new_max = FT_PAD_CEIL( new_max, 8 ); if ( new_max > FT_OUTLINE_POINTS_MAX ) return FT_THROW( Array_Too_Large ); if ( FT_RENEW_ARRAY( base->points, old_max, new_max ) || FT_RENEW_ARRAY( base->tags, old_max, new_max ) ) goto Exit; if ( loader->use_extra ) { if ( FT_RENEW_ARRAY( loader->base.extra_points, old_max * 2, new_max * 2 ) ) goto Exit; FT_ARRAY_MOVE( loader->base.extra_points + new_max, loader->base.extra_points + old_max, old_max ); loader->base.extra_points2 = loader->base.extra_points + new_max; } adjust = 1; loader->max_points = new_max; } error = FT_GlyphLoader_CreateExtra( loader ); if ( error ) return error; /* check contours */ old_max = loader->max_contours; new_max = (FT_UInt)base->n_contours + (FT_UInt)current->n_contours + n_contours; if ( new_max > old_max ) { new_max = FT_PAD_CEIL( new_max, 4 ); if ( new_max > FT_OUTLINE_CONTOURS_MAX ) return FT_THROW( Array_Too_Large ); if ( FT_RENEW_ARRAY( base->contours, old_max, new_max ) ) goto Exit; adjust = 1; loader->max_contours = new_max; } if ( adjust ) FT_GlyphLoader_Adjust_Points( loader ); Exit: if ( error ) FT_GlyphLoader_Reset( loader ); return error; } /* Ensure that we can add `n_subglyphs' to our glyph. this function */ /* reallocates its subglyphs table if necessary. Note that it DOES */ /* NOT change the number of subglyphs within the loader! */ /* */ FT_BASE_DEF( FT_Error ) FT_GlyphLoader_CheckSubGlyphs( FT_GlyphLoader loader, FT_UInt n_subs ) { FT_Memory memory = loader->memory; FT_Error error = FT_Err_Ok; FT_UInt new_max, old_max; FT_GlyphLoad base = &loader->base; FT_GlyphLoad current = &loader->current; new_max = base->num_subglyphs + current->num_subglyphs + n_subs; old_max = loader->max_subglyphs; if ( new_max > old_max ) { new_max = FT_PAD_CEIL( new_max, 2 ); if ( FT_RENEW_ARRAY( base->subglyphs, old_max, new_max ) ) goto Exit; loader->max_subglyphs = new_max; FT_GlyphLoader_Adjust_Subglyphs( loader ); } Exit: return error; } /* prepare loader for the addition of a new glyph on top of the base one */ FT_BASE_DEF( void ) FT_GlyphLoader_Prepare( FT_GlyphLoader loader ) { FT_GlyphLoad current = &loader->current; current->outline.n_points = 0; current->outline.n_contours = 0; current->num_subglyphs = 0; FT_GlyphLoader_Adjust_Points ( loader ); FT_GlyphLoader_Adjust_Subglyphs( loader ); } /* add current glyph to the base image -- and prepare for another */ FT_BASE_DEF( void ) FT_GlyphLoader_Add( FT_GlyphLoader loader ) { FT_GlyphLoad base; FT_GlyphLoad current; FT_Int n_curr_contours; FT_Int n_base_points; FT_Int n; if ( !loader ) return; base = &loader->base; current = &loader->current; n_curr_contours = current->outline.n_contours; n_base_points = base->outline.n_points; base->outline.n_points = (short)( base->outline.n_points + current->outline.n_points ); base->outline.n_contours = (short)( base->outline.n_contours + current->outline.n_contours ); base->num_subglyphs += current->num_subglyphs; /* adjust contours count in newest outline */ for ( n = 0; n < n_curr_contours; n++ ) current->outline.contours[n] = (short)( current->outline.contours[n] + n_base_points ); /* prepare for another new glyph image */ FT_GlyphLoader_Prepare( loader ); } /* END */