| // 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(); |
| |
| // 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(); |
| |
| private: |
| PageOrientation default_page_orientation_ = PageOrientation::kOriginal; |
| }; |
| |
| 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_ |