/*
* Copyright © 2022 Google, 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.
*
* Google Author(s): Garret Rieger
*/
#ifndef GRAPH_MARKBASEPOS_GRAPH_HH
#define GRAPH_MARKBASEPOS_GRAPH_HH
#include "split-helpers.hh"
#include "coverage-graph.hh"
#include "../OT/Layout/GPOS/MarkBasePos.hh"
#include "../OT/Layout/GPOS/PosLookupSubTable.hh"
namespace graph {
struct AnchorMatrix : public OT::Layout::GPOS_impl::AnchorMatrix
{
bool sanitize (graph_t::vertex_t& vertex, unsigned class_count) const
{
int64_t vertex_len = vertex.obj.tail - vertex.obj.head;
if (vertex_len < AnchorMatrix::min_size) return false;
return vertex_len >= AnchorMatrix::min_size +
OT::Offset16::static_size * class_count * this->rows;
}
bool shrink (gsubgpos_graph_context_t& c,
unsigned this_index,
unsigned old_class_count,
unsigned new_class_count)
{
if (new_class_count >= old_class_count) return false;
auto& o = c.graph.vertices_[this_index].obj;
unsigned base_count = rows;
o.tail = o.head +
AnchorMatrix::min_size +
OT::Offset16::static_size * base_count * new_class_count;
// Reposition links into the new indexing scheme.
for (auto& link : o.real_links.writer ())
{
unsigned index = (link.position - 2) / 2;
unsigned base = index / old_class_count;
unsigned klass = index % old_class_count;
if (klass >= new_class_count)
// should have already been removed
return false;
unsigned new_index = base * new_class_count + klass;
link.position = (char*) &(this->matrixZ[new_index]) - (char*) this;
}
return true;
}
unsigned clone (gsubgpos_graph_context_t& c,
unsigned this_index,
unsigned start,
unsigned end,
unsigned class_count)
{
unsigned base_count = rows;
unsigned new_class_count = end - start;
unsigned size = AnchorMatrix::min_size +
OT::Offset16::static_size * new_class_count * rows;
unsigned prime_id = c.create_node (size);
if (prime_id == (unsigned) -1) return -1;
AnchorMatrix* prime = (AnchorMatrix*) c.graph.object (prime_id).head;
prime->rows = base_count;
auto& o = c.graph.vertices_[this_index].obj;
int num_links = o.real_links.length;
for (int i = 0; i < num_links; i++)
{
const auto& link = o.real_links[i];
unsigned old_index = (link.position - 2) / OT::Offset16::static_size;
unsigned klass = old_index % class_count;
if (klass < start || klass >= end) continue;
unsigned base = old_index / class_count;
unsigned new_klass = klass - start;
unsigned new_index = base * new_class_count + new_klass;
unsigned child_idx = link.objidx;
c.graph.add_link (&(prime->matrixZ[new_index]),
prime_id,
child_idx);
auto& child = c.graph.vertices_[child_idx];
child.remove_parent (this_index);
o.real_links.remove (i);
num_links--;
i--;
}
return prime_id;
}
};
struct MarkArray : public OT::Layout::GPOS_impl::MarkArray
{
bool sanitize (graph_t::vertex_t& vertex) const
{
int64_t vertex_len = vertex.obj.tail - vertex.obj.head;
unsigned min_size = MarkArray::min_size;
if (vertex_len < min_size) return false;
return vertex_len >= get_size ();
}
bool shrink (gsubgpos_graph_context_t& c,
const hb_hashmap_t<unsigned, unsigned>& mark_array_links,
unsigned this_index,
unsigned new_class_count)
{
auto& o = c.graph.vertices_[this_index].obj;
for (const auto& link : o.real_links)
c.graph.vertices_[link.objidx].remove_parent (this_index);
o.real_links.reset ();
unsigned new_index = 0;
for (const auto& record : this->iter ())
{
unsigned klass = record.klass;
if (klass >= new_class_count) continue;
(*this)[new_index].klass = klass;
unsigned position = (char*) &record.markAnchor - (char*) this;
unsigned* objidx;
if (!mark_array_links.has (position, &objidx))
{
new_index++;
continue;
}
c.graph.add_link (&(*this)[new_index].markAnchor, this_index, *objidx);
new_index++;
}
this->len = new_index;
o.tail = o.head + MarkArray::min_size +
OT::Layout::GPOS_impl::MarkRecord::static_size * new_index;
return true;
}
unsigned clone (gsubgpos_graph_context_t& c,
unsigned this_index,
const hb_hashmap_t<unsigned, unsigned>& pos_to_index,
hb_set_t& marks,
unsigned start_class)
{
unsigned size = MarkArray::min_size +
OT::Layout::GPOS_impl::MarkRecord::static_size *
marks.get_population ();
unsigned prime_id = c.create_node (size);
if (prime_id == (unsigned) -1) return -1;
MarkArray* prime = (MarkArray*) c.graph.object (prime_id).head;
prime->len = marks.get_population ();
unsigned i = 0;
for (hb_codepoint_t mark : marks)
{
(*prime)[i].klass = (*this)[mark].klass - start_class;
unsigned offset_pos = (char*) &((*this)[mark].markAnchor) - (char*) this;
unsigned* anchor_index;
if (pos_to_index.has (offset_pos, &anchor_index))
c.graph.move_child (this_index,
&((*this)[mark].markAnchor),
prime_id,
&((*prime)[i].markAnchor));
i++;
}
return prime_id;
}
};
struct MarkBasePosFormat1 : public OT::Layout::GPOS_impl::MarkBasePosFormat1_2<SmallTypes>
{
bool sanitize (graph_t::vertex_t& vertex) const
{
int64_t vertex_len = vertex.obj.tail - vertex.obj.head;
return vertex_len >= MarkBasePosFormat1::static_size;
}
hb_vector_t<unsigned> split_subtables (gsubgpos_graph_context_t& c, unsigned this_index)
{
hb_set_t visited;
const unsigned base_coverage_id = c.graph.index_for_offset (this_index, &baseCoverage);
const unsigned base_size =
OT::Layout::GPOS_impl::PairPosFormat1_3<SmallTypes>::min_size +
MarkArray::min_size +
AnchorMatrix::min_size +
c.graph.vertices_[base_coverage_id].table_size ();
hb_vector_t<class_info_t> class_to_info = get_class_info (c, this_index);
unsigned class_count = classCount;
auto base_array = c.graph.as_table<AnchorMatrix> (this_index,
&baseArray,
class_count);
if (!base_array) return hb_vector_t<unsigned> ();
unsigned base_count = base_array.table->rows;
unsigned partial_coverage_size = 4;
unsigned accumulated = base_size;
hb_vector_t<unsigned> split_points;
for (unsigned klass = 0; klass < class_count; klass++)
{
class_info_t& info = class_to_info[klass];
partial_coverage_size += OT::HBUINT16::static_size * info.marks.get_population ();
unsigned accumulated_delta =
OT::Layout::GPOS_impl::MarkRecord::static_size * info.marks.get_population () +
OT::Offset16::static_size * base_count;
for (unsigned objidx : info.child_indices)
accumulated_delta += c.graph.find_subgraph_size (objidx, visited);
accumulated += accumulated_delta;
unsigned total = accumulated + partial_coverage_size;
if (total >= (1 << 16))
{
split_points.push (klass);
accumulated = base_size + accumulated_delta;
partial_coverage_size = 4 + OT::HBUINT16::static_size * info.marks.get_population ();
visited.clear (); // node sharing isn't allowed between splits.
}
}
const unsigned mark_array_id = c.graph.index_for_offset (this_index, &markArray);
split_context_t split_context {
c,
this,
this_index,
std::move (class_to_info),
c.graph.vertices_[mark_array_id].position_to_index_map (),
};
return actuate_subtable_split<split_context_t> (split_context, split_points);
}
private:
struct class_info_t {
hb_set_t marks;
hb_vector_t<unsigned> child_indices;
};
struct split_context_t {
gsubgpos_graph_context_t& c;
MarkBasePosFormat1* thiz;
unsigned this_index;
hb_vector_t<class_info_t> class_to_info;
hb_hashmap_t<unsigned, unsigned> mark_array_links;
hb_set_t marks_for (unsigned start, unsigned end)
{
hb_set_t marks;
for (unsigned klass = start; klass < end; klass++)
{
+ class_to_info[klass].marks.iter ()
| hb_sink (marks)
;
}
return marks;
}
unsigned original_count ()
{
return thiz->classCount;
}
unsigned clone_range (unsigned start, unsigned end)
{
return thiz->clone_range (*this, this->this_index, start, end);
}
bool shrink (unsigned count)
{
return thiz->shrink (*this, this->this_index, count);
}
};
hb_vector_t<class_info_t> get_class_info (gsubgpos_graph_context_t& c,
unsigned this_index)
{
hb_vector_t<class_info_t> class_to_info;
unsigned class_count= classCount;
class_to_info.resize (class_count);
auto mark_array = c.graph.as_table<MarkArray> (this_index, &markArray);
if (!mark_array) return hb_vector_t<class_info_t> ();
unsigned mark_count = mark_array.table->len;
for (unsigned mark = 0; mark < mark_count; mark++)
{
unsigned klass = (*mark_array.table)[mark].get_class ();
class_to_info[klass].marks.add (mark);
}
for (const auto& link : mark_array.vertex->obj.real_links)
{
unsigned mark = (link.position - 2) /
OT::Layout::GPOS_impl::MarkRecord::static_size;
unsigned klass = (*mark_array.table)[mark].get_class ();
class_to_info[klass].child_indices.push (link.objidx);
}
unsigned base_array_id =
c.graph.index_for_offset (this_index, &baseArray);
auto& base_array_v = c.graph.vertices_[base_array_id];
for (const auto& link : base_array_v.obj.real_links)
{
unsigned index = (link.position - 2) / OT::Offset16::static_size;
unsigned klass = index % class_count;
class_to_info[klass].child_indices.push (link.objidx);
}
return class_to_info;
}
bool shrink (split_context_t& sc,
unsigned this_index,
unsigned count)
{
DEBUG_MSG (SUBSET_REPACK, nullptr,
" Shrinking MarkBasePosFormat1 (%u) to [0, %u).",
this_index,
count);
unsigned old_count = classCount;
if (count >= old_count)
return true;
classCount = count;
auto mark_coverage = sc.c.graph.as_table<Coverage> (this_index,
&markCoverage);
if (!mark_coverage) return false;
hb_set_t marks = sc.marks_for (0, count);
auto new_coverage =
+ hb_zip (hb_range (), mark_coverage.table->iter ())
| hb_filter (marks, hb_first)
| hb_map_retains_sorting (hb_second)
;
if (!Coverage::make_coverage (sc.c, + new_coverage,
mark_coverage.index,
4 + 2 * marks.get_population ()))
return false;
auto base_array = sc.c.graph.as_table<AnchorMatrix> (this_index,
&baseArray,
old_count);
if (!base_array || !base_array.table->shrink (sc.c,
base_array.index,
old_count,
count))
return false;
auto mark_array = sc.c.graph.as_table<MarkArray> (this_index,
&markArray);
if (!mark_array || !mark_array.table->shrink (sc.c,
sc.mark_array_links,
mark_array.index,
count))
return false;
return true;
}
// Create a new MarkBasePos that has all of the data for classes from [start, end).
unsigned clone_range (split_context_t& sc,
unsigned this_index,
unsigned start, unsigned end) const
{
DEBUG_MSG (SUBSET_REPACK, nullptr,
" Cloning MarkBasePosFormat1 (%u) range [%u, %u).", this_index, start, end);
graph_t& graph = sc.c.graph;
unsigned prime_size = OT::Layout::GPOS_impl::MarkBasePosFormat1_2<SmallTypes>::static_size;
unsigned prime_id = sc.c.create_node (prime_size);
if (prime_id == (unsigned) -1) return -1;
MarkBasePosFormat1* prime = (MarkBasePosFormat1*) graph.object (prime_id).head;
prime->format = this->format;
unsigned new_class_count = end - start;
prime->classCount = new_class_count;
unsigned base_coverage_id =
graph.index_for_offset (sc.this_index, &baseCoverage);
graph.add_link (&(prime->baseCoverage), prime_id, base_coverage_id);
graph.duplicate (prime_id, base_coverage_id);
auto mark_coverage = sc.c.graph.as_table<Coverage> (this_index,
&markCoverage);
if (!mark_coverage) return false;
hb_set_t marks = sc.marks_for (start, end);
auto new_coverage =
+ hb_zip (hb_range (), mark_coverage.table->iter ())
| hb_filter (marks, hb_first)
| hb_map_retains_sorting (hb_second)
;
if (!Coverage::add_coverage (sc.c,
prime_id,
2,
+ new_coverage,
marks.get_population () * 2 + 4))
return -1;
auto mark_array =
graph.as_table <MarkArray> (sc.this_index, &markArray);
if (!mark_array) return -1;
unsigned new_mark_array =
mark_array.table->clone (sc.c,
mark_array.index,
sc.mark_array_links,
marks,
start);
graph.add_link (&(prime->markArray), prime_id, new_mark_array);
unsigned class_count = classCount;
auto base_array =
graph.as_table<AnchorMatrix> (sc.this_index, &baseArray, class_count);
if (!base_array) return -1;
unsigned new_base_array =
base_array.table->clone (sc.c,
base_array.index,
start, end, this->classCount);
graph.add_link (&(prime->baseArray), prime_id, new_base_array);
return prime_id;
}
};
struct MarkBasePos : public OT::Layout::GPOS_impl::MarkBasePos
{
hb_vector_t<unsigned> split_subtables (gsubgpos_graph_context_t& c,
unsigned this_index)
{
switch (u.format) {
case 1:
return ((MarkBasePosFormat1*)(&u.format1))->split_subtables (c, this_index);
#ifndef HB_NO_BORING_EXPANSION
case 2: HB_FALLTHROUGH;
// Don't split 24bit PairPos's.
#endif
default:
return hb_vector_t<unsigned> ();
}
}
bool sanitize (graph_t::vertex_t& vertex) const
{
int64_t vertex_len = vertex.obj.tail - vertex.obj.head;
if (vertex_len < u.format.get_size ()) return false;
switch (u.format) {
case 1:
return ((MarkBasePosFormat1*)(&u.format1))->sanitize (vertex);
#ifndef HB_NO_BORING_EXPANSION
case 2: HB_FALLTHROUGH;
#endif
default:
// We don't handle format 3 and 4 here.
return false;
}
}
};
}
#endif // GRAPH_MARKBASEPOS_GRAPH_HH
