Revert "reland of Improve linearized pdf load/show time."

pdf/range_set.cc

-// Copyright 2016 The Chromium Authors. All rights reserved.
-// Use of this source code is governed by a BSD-style license that can be
-// found in the LICENSE file.
-
-#include "pdf/range_set.h"
-
-#include <algorithm>
-#include <sstream>
-#include <vector>
-
-namespace chrome_pdf {
-
-namespace {
-
-gfx::Range FixDirection(const gfx::Range& range) {
-  if (!range.IsValid() || !range.is_reversed())
-    return range;
-  return gfx::Range(range.end() + 1, range.start() + 1);
-}
-
-}  // namespace
-
-RangeSet::RangeSet() {}
-
-RangeSet::RangeSet(const gfx::Range& range) {
-  Union(range);
-}
-
-RangeSet::RangeSet(const RangeSet& range_set) : ranges_(range_set.ranges_) {}
-
-RangeSet::RangeSet(RangeSet&& range_set)
-    : ranges_(std::move(range_set.ranges_)) {}
-
-RangeSet& RangeSet::operator=(const RangeSet& other) {
-  ranges_ = other.ranges_;
-  return *this;
-}
-
-RangeSet::~RangeSet() {}
-
-bool RangeSet::operator==(const RangeSet& other) const {
-  return other.ranges_ == ranges_;
-}
-
-bool RangeSet::operator!=(const RangeSet& other) const {
-  return other.ranges_ != ranges_;
-}
-
-void RangeSet::Union(const gfx::Range& range) {
-  if (range.is_empty())
-    return;
-  gfx::Range fixed_range = FixDirection(range);
-  if (IsEmpty()) {
-    ranges_.insert(fixed_range);
-    return;
-  }
-
-  auto start = ranges_.upper_bound(fixed_range);
-  if (start != ranges_.begin())
-    --start;  // start now points to the key equal or lower than offset.
-  if (start->end() < fixed_range.start())
-    ++start;  // start element is entirely before current range, skip it.
-
-  auto end = ranges_.upper_bound(gfx::Range(fixed_range.end()));
-  if (start == end) {  // No ranges to merge.
-    ranges_.insert(fixed_range);
-    return;
-  }
-
-  --end;
-
-  int new_start = std::min<size_t>(start->start(), fixed_range.start());
-  int new_end = std::max(end->end(), fixed_range.end());
-
-  ranges_.erase(start, ++end);
-  ranges_.insert(gfx::Range(new_start, new_end));
-}
-
-void RangeSet::Union(const RangeSet& range_set) {
-  if (&range_set == this)
-    return;
-  for (const auto& it : range_set.ranges()) {
-    Union(it);
-  }
-}
-
-bool RangeSet::Contains(uint32_t point) const {
-  return Contains(gfx::Range(point, point + 1));
-}
-
-bool RangeSet::Contains(const gfx::Range& range) const {
-  if (range.is_empty())
-    return false;
-  const gfx::Range fixed_range = FixDirection(range);
-  auto it = ranges().upper_bound(fixed_range);
-  if (it == ranges().begin())
-    return false;  // No ranges includes range.start().
-
-  --it;  // Now it starts equal or before range.start().
-  return it->end() >= fixed_range.end();
-}
-
-bool RangeSet::Contains(const RangeSet& range_set) const {
-  for (const auto& it : range_set.ranges()) {
-    if (!Contains(it))
-      return false;
-  }
-  return true;
-}
-
-bool RangeSet::Intersects(const gfx::Range& range) const {
-  if (IsEmpty() || range.is_empty())
-    return false;
-  const gfx::Range fixed_range = FixDirection(range);
-  auto start = ranges_.upper_bound(fixed_range);
-  if (start != ranges_.begin()) {
-    --start;
-  }
-  // start now points to the key equal or lower than range.start().
-  if (start->end() < range.start()) {
-    // start element is entirely before current range, skip it.
-    ++start;
-  }
-  auto end = ranges_.upper_bound(gfx::Range(fixed_range.end()));
-  for (auto it = start; it != end; ++it) {
-    if (fixed_range.end() > it->start() && fixed_range.start() < it->end())
-      return true;
-  }
-  return false;
-}
-
-bool RangeSet::Intersects(const RangeSet& range_set) const {
-  for (const auto& it : range_set.ranges()) {
-    if (Intersects(it))
-      return true;
-  }
-  return false;
-}
-
-void RangeSet::Intersect(const gfx::Range& range) {
-  Intersect(RangeSet(range));
-}
-
-void RangeSet::Intersect(const RangeSet& range_set) {
-  if (IsEmpty())
-    return;
-  RangesContainer new_ranges;
-  for (const auto& range : range_set.ranges()) {
-    auto start = ranges_.upper_bound(range);
-    if (start != ranges_.begin())
-      --start;  // start now points to the key equal or lower than
-                // range.start().
-    if (start->end() < range.start())
-      ++start;  // start element is entirely before current range, skip it.
-    auto end = ranges_.upper_bound(gfx::Range(range.end()));
-    if (start == end) {  // No data in the current range available.
-      continue;
-    }
-    for (auto it = start; it != end; ++it) {
-      const gfx::Range new_range = range.Intersect(*it);
-      if (!new_range.is_empty()) {
-        new_ranges.insert(new_range);
-      }
-    }
-  }
-  new_ranges.swap(ranges_);
-}
-
-void RangeSet::Subtract(const gfx::Range& range) {
-  if (range.is_empty() || IsEmpty())
-    return;
-  const gfx::Range fixed_range = FixDirection(range);
-  auto start = ranges_.upper_bound(fixed_range);
-  if (start != ranges_.begin())
-    --start;  // start now points to the key equal or lower than
-              // range.start().
-  if (start->end() < fixed_range.start())
-    ++start;  // start element is entirely before current range, skip it.
-  auto end = ranges_.upper_bound(gfx::Range(fixed_range.end()));
-  if (start == end) {  // No data in the current range available.
-    return;
-  }
-  std::vector<gfx::Range> new_ranges;
-  for (auto it = start; it != end; ++it) {
-    const gfx::Range left(it->start(),
-                          std::min(it->end(), fixed_range.start()));
-    const gfx::Range right(std::max(it->start(), fixed_range.end()), it->end());
-    if (!left.is_empty() && !left.is_reversed()) {
-      new_ranges.push_back(left);
-    }
-    if (!right.is_empty() && !right.is_reversed() && right != left) {
-      new_ranges.push_back(right);
-    }
-  }
-  ranges_.erase(start, end);
-  for (const auto& it : new_ranges) {
-    ranges_.insert(it);
-  }
-}
-
-void RangeSet::Subtract(const RangeSet& range_set) {
-  if (&range_set == this) {
-    ranges_.clear();
-    return;
-  }
-  for (const auto& range : range_set.ranges()) {
-    Subtract(range);
-  }
-}
-
-void RangeSet::Xor(const gfx::Range& range) {
-  Xor(RangeSet(range));
-}
-
-void RangeSet::Xor(const RangeSet& range_set) {
-  RangeSet tmp = *this;
-  tmp.Intersect(range_set);
-  Union(range_set);
-  Subtract(tmp);
-}
-
-bool RangeSet::IsEmpty() const {
-  return ranges().empty();
-}
-
-void RangeSet::Clear() {
-  ranges_.clear();
-}
-
-gfx::Range RangeSet::First() const {
-  return *ranges().begin();
-}
-
-gfx::Range RangeSet::Last() const {
-  return *ranges().rbegin();
-}
-
-std::string RangeSet::ToString() const {
-  std::stringstream ss;
-  ss << "{";
-  for (const auto& it : ranges()) {
-    ss << "[" << it.start() << "," << it.end() << ")";
-  }
-  ss << "}";
-  return ss.str();
-}
-
-}  // namespace chrome_pdf
-
-std::ostream& operator<<(std::ostream& os,
-                         const chrome_pdf::RangeSet& range_set) {
-  return (os << range_set.ToString());
-}