| // Copyright 2019 The Chromium Authors |
| // 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/check_op.h" |
| #include"base/i18n/rtl.h" |
| #include"base/values.h" |
| #include"pdf/page_orientation.h" |
| #include"ui/gfx/geometry/insets.h" |
| #include"ui/gfx/geometry/rect.h" |
| #include"ui/gfx/geometry/size.h" |
| |
| 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. |
| classDocumentLayoutfinal{ |
| public: |
| // TODO(crbug.com/40155509): Add `kTwoUpEven` page spread support. |
| enumclassPageSpread{ |
| kOneUp=0,// One page per spread. |
| kTwoUpOdd=1,// Two pages per spread, with odd pages first. |
| }; |
| |
| // Options controlling layout behavior. |
| classOptionsfinal{ |
| public: |
| Options(); |
| |
| Options(constOptions& other); |
| Options&operator=(constOptions& other); |
| |
| ~Options(); |
| |
| friendbooloperator==(constOptions& lhs,constOptions& rhs){ |
| return lhs.direction()== rhs.direction()&& |
| lhs.default_page_orientation()== rhs.default_page_orientation()&& |
| lhs.page_spread()== rhs.page_spread(); |
| } |
| |
| friendbooloperator!=(constOptions& lhs,constOptions& rhs){ |
| return!(lhs== rhs); |
| } |
| |
| // Serializes layout options to a base::Value::Dict. |
| base::Value::DictToValue()const; |
| |
| // Deserializes layout options from a base::Value::Dict. |
| voidFromValue(constbase::Value::Dict& value); |
| |
| // Page layout direction. This is tied to the direction of the user's UI, |
| // rather than the direction of individual pages. |
| base::i18n::TextDirection direction()const{return direction_;} |
| |
| void set_direction(base::i18n::TextDirection direction){ |
| direction_= direction; |
| } |
| |
| PageOrientation default_page_orientation()const{ |
| return default_page_orientation_; |
| } |
| |
| // Rotates default page orientation 90 degrees clockwise. |
| voidRotatePagesClockwise(); |
| |
| // Rotates default page orientation 90 degrees counterclockwise. |
| voidRotatePagesCounterclockwise(); |
| |
| PageSpread page_spread()const{return page_spread_;} |
| |
| // Changes two-up view status. |
| void set_page_spread(PageSpread spread){ page_spread_= spread;} |
| |
| private: |
| base::i18n::TextDirection direction_=base::i18n::UNKNOWN_DIRECTION; |
| PageOrientation default_page_orientation_=PageOrientation::kOriginal; |
| PageSpread page_spread_=PageSpread::kOneUp; |
| }; |
| |
| staticconstexpr gfx::Insets kSingleViewInsets= |
| gfx::Insets::TLBR(/*top=*/3,/*left=*/5,/*bottom=*/7,/*right=*/5); |
| staticconstexprint32_t kBottomSeparator=4; |
| staticconstexprint32_t kHorizontalSeparator=1; |
| |
| DocumentLayout(); |
| |
| DocumentLayout(constDocumentLayout& other)=delete; |
| DocumentLayout&operator=(constDocumentLayout& other)=delete; |
| |
| ~DocumentLayout(); |
| |
| // Returns the layout options. |
| constOptions& 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. |
| voidSetOptions(constOptions& 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 gfx::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 gfx::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 gfx::Rect& page_bounds_rect(size_t page_index)const{ |
| DCHECK_LT(page_index, page_count()); |
| return page_layouts_[page_index].inner_rect; |
| } |
| |
| // Computes the layout for a given list of `page_sizes` based on `options_`. |
| voidComputeLayout(const std::vector<gfx::Size>& page_sizes); |
| |
| private: |
| // Layout of a single page. |
| structPageLayout{ |
| // Bounding rectangle for the page with decorations. |
| gfx::Rect outer_rect; |
| |
| // Bounding rectangle for the page without decorations. |
| gfx::Rect inner_rect; |
| }; |
| |
| // Helpers for ComputeLayout() handling different page spreads. |
| voidComputeOneUpLayout(const std::vector<gfx::Size>& page_sizes); |
| voidComputeTwoUpOddLayout(const std::vector<gfx::Size>& page_sizes); |
| |
| // Copies `source_rect` to `destination_rect`, setting `dirty_` to true if |
| // `destination_rect` is modified as a result. |
| voidCopyRectIfModified(const gfx::Rect& source_rect, |
| gfx::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. |
| gfx::Size size_; |
| |
| std::vector<PageLayout> page_layouts_; |
| }; |
| |
| }// namespace chrome_pdf |
| |
| #endif// PDF_DOCUMENT_LAYOUT_H_ |
