harfbuzz/src/hb-subset-cff2.cc

458 lines
13 KiB
C++

/*
* Copyright © 2018 Adobe Inc.
*
* This is part of HarfBuzz, a text shaping library.
*
* Permission is hereby granted, without written agreement and without
* license or royalty fees, to use, copy, modify, and distribute this
* software and its documentation for any purpose, provided that the
* above copyright notice and the following two paragraphs appear in
* all copies of this software.
*
* IN NO EVENT SHALL THE COPYRIGHT HOLDER BE LIABLE TO ANY PARTY FOR
* DIRECT, INDIRECT, SPECIAL, INCIDENTAL, OR CONSEQUENTIAL DAMAGES
* ARISING OUT OF THE USE OF THIS SOFTWARE AND ITS DOCUMENTATION, EVEN
* IF THE COPYRIGHT HOLDER HAS BEEN ADVISED OF THE POSSIBILITY OF SUCH
* DAMAGE.
*
* THE COPYRIGHT HOLDER SPECIFICALLY DISCLAIMS ANY WARRANTIES, INCLUDING,
* BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND
* FITNESS FOR A PARTICULAR PURPOSE. THE SOFTWARE PROVIDED HEREUNDER IS
* ON AN "AS IS" BASIS, AND THE COPYRIGHT HOLDER HAS NO OBLIGATION TO
* PROVIDE MAINTENANCE, SUPPORT, UPDATES, ENHANCEMENTS, OR MODIFICATIONS.
*
* Adobe Author(s): Michiharu Ariza
*/
#include "hb.hh"
#ifndef HB_NO_SUBSET_CFF
#include "hb-open-type.hh"
#include "hb-ot-cff2-table.hh"
#include "hb-set.h"
#include "hb-subset-cff2.hh"
#include "hb-subset-plan.hh"
#include "hb-subset-cff-common.hh"
#include "hb-cff2-interp-cs.hh"
using namespace CFF;
struct cff2_sub_table_info_t : cff_sub_table_info_t
{
cff2_sub_table_info_t ()
: cff_sub_table_info_t (),
var_store_link (0)
{}
objidx_t var_store_link;
};
struct cff2_top_dict_op_serializer_t : cff_top_dict_op_serializer_t<>
{
bool serialize (hb_serialize_context_t *c,
const op_str_t &opstr,
const cff2_sub_table_info_t &info) const
{
TRACE_SERIALIZE (this);
switch (opstr.op)
{
case OpCode_vstore:
return_trace (FontDict::serialize_link4_op(c, opstr.op, info.var_store_link));
default:
return_trace (cff_top_dict_op_serializer_t<>::serialize (c, opstr, info));
}
}
};
struct cff2_cs_opset_flatten_t : cff2_cs_opset_t<cff2_cs_opset_flatten_t, flatten_param_t, blend_arg_t>
{
static void flush_args_and_op (op_code_t op, cff2_cs_interp_env_t<blend_arg_t> &env, flatten_param_t& param)
{
switch (op)
{
case OpCode_return:
case OpCode_endchar:
/* dummy opcodes in CFF2. ignore */
break;
case OpCode_hstem:
case OpCode_hstemhm:
case OpCode_vstem:
case OpCode_vstemhm:
case OpCode_hintmask:
case OpCode_cntrmask:
if (param.drop_hints)
{
env.clear_args ();
return;
}
HB_FALLTHROUGH;
default:
SUPER::flush_args_and_op (op, env, param);
break;
}
}
static void flush_args (cff2_cs_interp_env_t<blend_arg_t> &env, flatten_param_t& param)
{
for (unsigned int i = 0; i < env.argStack.get_count ();)
{
const blend_arg_t &arg = env.argStack[i];
if (arg.blending ())
{
if (unlikely (!((arg.numValues > 0) && (env.argStack.get_count () >= arg.numValues))))
{
env.set_error ();
return;
}
flatten_blends (arg, i, env, param);
i += arg.numValues;
}
else
{
str_encoder_t encoder (param.flatStr);
encoder.encode_num (arg);
i++;
}
}
SUPER::flush_args (env, param);
}
static void flatten_blends (const blend_arg_t &arg, unsigned int i, cff2_cs_interp_env_t<blend_arg_t> &env, flatten_param_t& param)
{
/* flatten the default values */
str_encoder_t encoder (param.flatStr);
for (unsigned int j = 0; j < arg.numValues; j++)
{
const blend_arg_t &arg1 = env.argStack[i + j];
if (unlikely (!((arg1.blending () && (arg.numValues == arg1.numValues) && (arg1.valueIndex == j) &&
(arg1.deltas.length == env.get_region_count ())))))
{
env.set_error ();
return;
}
encoder.encode_num (arg1);
}
/* flatten deltas for each value */
for (unsigned int j = 0; j < arg.numValues; j++)
{
const blend_arg_t &arg1 = env.argStack[i + j];
for (unsigned int k = 0; k < arg1.deltas.length; k++)
encoder.encode_num (arg1.deltas[k]);
}
/* flatten the number of values followed by blend operator */
encoder.encode_int (arg.numValues);
encoder.encode_op (OpCode_blendcs);
}
static void flush_op (op_code_t op, cff2_cs_interp_env_t<blend_arg_t> &env, flatten_param_t& param)
{
switch (op)
{
case OpCode_return:
case OpCode_endchar:
return;
default:
str_encoder_t encoder (param.flatStr);
encoder.encode_op (op);
}
}
private:
typedef cff2_cs_opset_t<cff2_cs_opset_flatten_t, flatten_param_t, blend_arg_t> SUPER;
typedef cs_opset_t<blend_arg_t, cff2_cs_opset_flatten_t, cff2_cs_opset_flatten_t, cff2_cs_interp_env_t<blend_arg_t>, flatten_param_t> CSOPSET;
};
struct cff2_cs_opset_subr_subset_t : cff2_cs_opset_t<cff2_cs_opset_subr_subset_t, subr_subset_param_t, blend_arg_t>
{
static void process_op (op_code_t op, cff2_cs_interp_env_t<blend_arg_t> &env, subr_subset_param_t& param)
{
switch (op) {
case OpCode_return:
param.current_parsed_str->set_parsed ();
env.return_from_subr ();
param.set_current_str (env, false);
break;
case OpCode_endchar:
param.current_parsed_str->set_parsed ();
SUPER::process_op (op, env, param);
break;
case OpCode_callsubr:
process_call_subr (op, CSType_LocalSubr, env, param, env.localSubrs, param.local_closure);
break;
case OpCode_callgsubr:
process_call_subr (op, CSType_GlobalSubr, env, param, env.globalSubrs, param.global_closure);
break;
default:
SUPER::process_op (op, env, param);
param.current_parsed_str->add_op (op, env.str_ref);
break;
}
}
protected:
static void process_call_subr (op_code_t op, cs_type_t type,
cff2_cs_interp_env_t<blend_arg_t> &env, subr_subset_param_t& param,
cff2_biased_subrs_t& subrs, hb_set_t *closure)
{
byte_str_ref_t str_ref = env.str_ref;
env.call_subr (subrs, type);
param.current_parsed_str->add_call_op (op, str_ref, env.context.subr_num);
closure->add (env.context.subr_num);
param.set_current_str (env, true);
}
private:
typedef cff2_cs_opset_t<cff2_cs_opset_subr_subset_t, subr_subset_param_t, blend_arg_t> SUPER;
};
struct cff2_subr_subsetter_t : subr_subsetter_t<cff2_subr_subsetter_t, CFF2Subrs, const OT::cff2::accelerator_subset_t, cff2_cs_interp_env_t<blend_arg_t>, cff2_cs_opset_subr_subset_t>
{
cff2_subr_subsetter_t (const OT::cff2::accelerator_subset_t &acc_, const hb_subset_plan_t *plan_)
: subr_subsetter_t (acc_, plan_) {}
static void complete_parsed_str (cff2_cs_interp_env_t<blend_arg_t> &env, subr_subset_param_t& param, parsed_cs_str_t &charstring)
{
/* vsindex is inserted at the beginning of the charstring as necessary */
if (env.seen_vsindex ())
{
number_t ivs;
ivs.set_int ((int)env.get_ivs ());
charstring.set_prefix (ivs, OpCode_vsindexcs);
}
}
};
struct cff2_subset_plan {
bool create (const OT::cff2::accelerator_subset_t &acc,
hb_subset_plan_t *plan)
{
orig_fdcount = acc.fdArray->count;
drop_hints = plan->flags & HB_SUBSET_FLAGS_NO_HINTING;
desubroutinize = plan->flags & HB_SUBSET_FLAGS_DESUBROUTINIZE;
if (desubroutinize)
{
/* Flatten global & local subrs */
subr_flattener_t<const OT::cff2::accelerator_subset_t, cff2_cs_interp_env_t<blend_arg_t>, cff2_cs_opset_flatten_t>
flattener(acc, plan);
if (!flattener.flatten (subset_charstrings))
return false;
}
else
{
cff2_subr_subsetter_t subr_subsetter (acc, plan);
/* Subset subrs: collect used subroutines, leaving all unused ones behind */
if (!subr_subsetter.subset ())
return false;
/* encode charstrings, global subrs, local subrs with new subroutine numbers */
if (!subr_subsetter.encode_charstrings (subset_charstrings))
return false;
if (!subr_subsetter.encode_globalsubrs (subset_globalsubrs))
return false;
/* local subrs */
if (!subset_localsubrs.resize (orig_fdcount))
return false;
for (unsigned int fd = 0; fd < orig_fdcount; fd++)
{
subset_localsubrs[fd].init ();
if (!subr_subsetter.encode_localsubrs (fd, subset_localsubrs[fd]))
return false;
}
}
/* FDSelect */
if (acc.fdSelect != &Null (CFF2FDSelect))
{
if (unlikely (!hb_plan_subset_cff_fdselect (plan,
orig_fdcount,
*(const FDSelect *)acc.fdSelect,
subset_fdcount,
subset_fdselect_size,
subset_fdselect_format,
subset_fdselect_ranges,
fdmap)))
return false;
}
else
fdmap.identity (1);
return true;
}
cff2_sub_table_info_t info;
unsigned int orig_fdcount = 0;
unsigned int subset_fdcount = 1;
unsigned int subset_fdselect_size = 0;
unsigned int subset_fdselect_format = 0;
hb_vector_t<code_pair_t> subset_fdselect_ranges;
hb_inc_bimap_t fdmap;
str_buff_vec_t subset_charstrings;
str_buff_vec_t subset_globalsubrs;
hb_vector_t<str_buff_vec_t> subset_localsubrs;
bool drop_hints = false;
bool desubroutinize = false;
};
static bool _serialize_cff2 (hb_serialize_context_t *c,
cff2_subset_plan &plan,
const OT::cff2::accelerator_subset_t &acc,
unsigned int num_glyphs)
{
/* private dicts & local subrs */
hb_vector_t<table_info_t> private_dict_infos;
if (unlikely (!private_dict_infos.resize (plan.subset_fdcount))) return false;
for (int i = (int)acc.privateDicts.length; --i >= 0 ;)
{
if (plan.fdmap.has (i))
{
objidx_t subrs_link = 0;
if (plan.subset_localsubrs[i].length > 0)
{
CFF2Subrs *dest = c->start_embed <CFF2Subrs> ();
if (unlikely (!dest)) return false;
c->push ();
if (likely (dest->serialize (c, plan.subset_localsubrs[i])))
subrs_link = c->pop_pack ();
else
{
c->pop_discard ();
return false;
}
}
PrivateDict *pd = c->start_embed<PrivateDict> ();
if (unlikely (!pd)) return false;
c->push ();
cff_private_dict_op_serializer_t privSzr (plan.desubroutinize, plan.drop_hints);
if (likely (pd->serialize (c, acc.privateDicts[i], privSzr, subrs_link)))
{
unsigned fd = plan.fdmap[i];
private_dict_infos[fd].size = c->length ();
private_dict_infos[fd].link = c->pop_pack ();
}
else
{
c->pop_discard ();
return false;
}
}
}
/* CharStrings */
{
CFF2CharStrings *cs = c->start_embed<CFF2CharStrings> ();
if (unlikely (!cs)) return false;
c->push ();
if (likely (cs->serialize (c, plan.subset_charstrings)))
plan.info.char_strings_link = c->pop_pack ();
else
{
c->pop_discard ();
return false;
}
}
/* FDSelect */
if (acc.fdSelect != &Null (CFF2FDSelect))
{
c->push ();
if (likely (hb_serialize_cff_fdselect (c, num_glyphs, *(const FDSelect *)acc.fdSelect, plan.orig_fdcount,
plan.subset_fdselect_format, plan.subset_fdselect_size,
plan.subset_fdselect_ranges)))
plan.info.fd_select.link = c->pop_pack ();
else
{
c->pop_discard ();
return false;
}
}
/* FDArray (FD Index) */
{
c->push ();
CFF2FDArray *fda = c->start_embed<CFF2FDArray> ();
if (unlikely (!fda)) return false;
cff_font_dict_op_serializer_t fontSzr;
auto it =
+ hb_zip (+ hb_iter (acc.fontDicts)
| hb_filter ([&] (const cff2_font_dict_values_t &_)
{ return plan.fdmap.has (&_ - &acc.fontDicts[0]); }),
hb_iter (private_dict_infos))
;
if (unlikely (!fda->serialize (c, it, fontSzr))) return false;
plan.info.fd_array_link = c->pop_pack ();
}
/* variation store */
if (acc.varStore != &Null (CFF2VariationStore))
{
c->push ();
CFF2VariationStore *dest = c->start_embed<CFF2VariationStore> ();
if (unlikely (!dest || !dest->serialize (c, acc.varStore))) return false;
plan.info.var_store_link = c->pop_pack ();
}
OT::cff2 *cff2 = c->allocate_min<OT::cff2> ();
if (unlikely (!cff2)) return false;
/* header */
cff2->version.major = 0x02;
cff2->version.minor = 0x00;
cff2->topDict = OT::cff2::static_size;
/* top dict */
{
TopDict &dict = cff2 + cff2->topDict;
cff2_top_dict_op_serializer_t topSzr;
if (unlikely (!dict.serialize (c, acc.topDict, topSzr, plan.info))) return false;
cff2->topDictSize = c->head - (const char *)&dict;
}
/* global subrs */
{
CFF2Subrs *dest = c->start_embed <CFF2Subrs> ();
if (unlikely (!dest)) return false;
return dest->serialize (c, plan.subset_globalsubrs);
}
}
static bool
_hb_subset_cff2 (const OT::cff2::accelerator_subset_t &acc,
hb_subset_context_t *c)
{
cff2_subset_plan cff2_plan;
if (unlikely (!cff2_plan.create (acc, c->plan))) return false;
return _serialize_cff2 (c->serializer, cff2_plan, acc, c->plan->num_output_glyphs ());
}
bool
hb_subset_cff2 (hb_subset_context_t *c)
{
OT::cff2::accelerator_subset_t acc (c->plan->source);
return acc.is_valid () && _hb_subset_cff2 (acc, c);
}
#endif