blob: c56cbc6bca7e888eb963f1a8e624aa904a00b770 [file] [log] [blame]
// Copyright 2019 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.
#ifndef PDF_DOCUMENT_LAYOUT_H_
#define PDF_DOCUMENT_LAYOUT_H_
#include <cstddef>
#include <vector>
#include "base/logging.h"
#include "pdf/draw_utils/coordinates.h"
#include "pdf/page_orientation.h"
#include "ppapi/cpp/rect.h"
#include "ppapi/cpp/size.h"
namespace pp {
class Var;
} // namespace pp
namespace chrome_pdf {
// Layout of pages within a PDF document. Pages are placed as rectangles
// (possibly rotated) in a non-overlapping vertical sequence.
//
// All layout units are pixels.
//
// The |Options| class controls the behavior of the layout, such as the default
// orientation of pages.
class DocumentLayout final {
public:
// Options controlling layout behavior.
class Options final {
public:
Options();
Options(const Options& other);
Options& operator=(const Options& other);
~Options();
friend bool operator==(const Options& lhs, const Options& rhs) {
return lhs.two_up_view_enabled() == rhs.two_up_view_enabled() &&
lhs.default_page_orientation() == rhs.default_page_orientation();
}
friend bool operator!=(const Options& lhs, const Options& rhs) {
return !(lhs == rhs);
}
// Serializes layout options to a pp::Var.
pp::Var ToVar() const;
// Deserializes layout options from a pp::Var.
void FromVar(const pp::Var& var);
PageOrientation default_page_orientation() const {
return default_page_orientation_;
}
// Rotates default page orientation 90 degrees clockwise.
void RotatePagesClockwise();
// Rotates default page orientation 90 degrees counterclockwise.
void RotatePagesCounterclockwise();
bool two_up_view_enabled() const { return two_up_view_enabled_; }
// Changes two-up view status.
void set_two_up_view_enabled(bool enable) { two_up_view_enabled_ = enable; }
private:
PageOrientation default_page_orientation_ = PageOrientation::kOriginal;
bool two_up_view_enabled_ = false;
};
static const draw_utils::PageInsetSizes kSingleViewInsets;
static constexpr int32_t kBottomSeparator = 4;
static constexpr int32_t kHorizontalSeparator = 1;
DocumentLayout();
DocumentLayout(const DocumentLayout& other) = delete;
DocumentLayout& operator=(const DocumentLayout& other) = delete;
~DocumentLayout();
// Returns the layout options.
const Options& options() const { return options_; }
// Sets the layout options. If certain options with immediate effect change
// (such as the default page orientation), the layout will be marked dirty.
//
// TODO(kmoon): We shouldn't have layout options that take effect immediately.
void SetOptions(const Options& options);
// Returns true if the layout has been modified since the last call to
// clear_dirty(). The initial state is false (clean), which assumes
// appropriate default behavior for an initially empty layout.
bool dirty() const { return dirty_; }
// Clears the dirty() state of the layout. This should be called after any
// layout changes have been applied.
void clear_dirty() { dirty_ = false; }
// Returns the layout's total size.
const pp::Size& size() const { return size_; }
size_t page_count() const { return page_layouts_.size(); }
// Gets the layout rectangle for a page. Only valid after computing a layout.
const pp::Rect& page_rect(size_t page_index) const {
DCHECK_LT(page_index, page_count());
return page_layouts_[page_index].outer_rect;
}
// Gets the layout rectangle for a page's bounds (which excludes additional
// regions like page shadows). Only valid after computing a layout.
const pp::Rect& page_bounds_rect(size_t page_index) const {
DCHECK_LT(page_index, page_count());
return page_layouts_[page_index].inner_rect;
}
// Computes layout that represent |page_sizes| formatted for single view.
//
// TODO(kmoon): Control layout type using an option.
void ComputeSingleViewLayout(const std::vector<pp::Size>& page_sizes);
// Computes layout that represent |page_sizes| formatted for two-up view.
//
// TODO(kmoon): Control layout type using an option.
void ComputeTwoUpViewLayout(const std::vector<pp::Size>& page_sizes);
private:
// Layout of a single page.
struct PageLayout {
// Bounding rectangle for the page with decorations.
pp::Rect outer_rect;
// Bounding rectangle for the page without decorations.
pp::Rect inner_rect;
};
// Copies |source_rect| to |destination_rect|, setting |dirty_| to true if
// |destination_rect| is modified as a result.
void CopyRectIfModified(const pp::Rect& source_rect,
pp::Rect* destination_rect);
Options options_;
// Indicates if the layout has changed in an externally-observable way,
// usually as a result of calling |ComputeLayout()| with different inputs.
//
// Some operations that may trigger layout changes:
// * Changing page sizes
// * Adding or removing pages
// * Changing page orientations
bool dirty_ = false;
// Layout's total size.
pp::Size size_;
std::vector<PageLayout> page_layouts_;
};
} // namespace chrome_pdf
#endif // PDF_DOCUMENT_LAYOUT_H_