PDF4QT/Pdf4QtLib/sources/pdfpage.h
2021-09-27 11:14:20 +02:00

323 lines
12 KiB
C++

// Copyright (C) 2018-2021 Jakub Melka
//
// This file is part of PDF4QT.
//
// PDF4QT is free software: you can redistribute it and/or modify
// it under the terms of the GNU Lesser General Public License as published by
// the Free Software Foundation, either version 3 of the License, or
// with the written consent of the copyright owner, any later version.
//
// PDF4QT is distributed in the hope that it will be useful,
// but WITHOUT ANY WARRANTY; without even the implied warranty of
// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
// GNU Lesser General Public License for more details.
//
// You should have received a copy of the GNU Lesser General Public License
// along with PDF4QT. If not, see <https://www.gnu.org/licenses/>.
#ifndef PDFPAGE_H
#define PDFPAGE_H
#include "pdfobject.h"
#include <QRectF>
#include <set>
#include <optional>
namespace pdf
{
class PDFDocument;
class PDFObjectStorage;
/// This enum represents number of degree, which should be page rotated CLOCKWISE,
/// when being displayed or printed.
enum class PageRotation
{
None,
Rotate90,
Rotate180,
Rotate270
};
enum class PageTabOrder
{
Invalid,
Row,
Column,
Structure,
Array,
Widget
};
constexpr PageRotation getPageRotationRotatedRight(PageRotation rotation)
{
switch (rotation)
{
case PageRotation::None:
return PageRotation::Rotate90;
case PageRotation::Rotate90:
return PageRotation::Rotate180;
case PageRotation::Rotate180:
return PageRotation::Rotate270;
case PageRotation::Rotate270:
return PageRotation::None;
}
return PageRotation::None;
}
constexpr PageRotation getPageRotationRotatedLeft(PageRotation rotation)
{
switch (rotation)
{
case PageRotation::None:
return PageRotation::Rotate270;
case PageRotation::Rotate90:
return PageRotation::None;
case PageRotation::Rotate180:
return PageRotation::Rotate90;
case PageRotation::Rotate270:
return PageRotation::Rotate180;
}
return PageRotation::None;
}
constexpr PageRotation getPageRotationCombined(PageRotation r1, PageRotation r2)
{
while (r1 != PageRotation::None)
{
r2 = getPageRotationRotatedRight(r2);
r1 = getPageRotationRotatedLeft(r1);
}
return r2;
}
constexpr PageRotation getPageRotationInversed(PageRotation rotation)
{
switch (rotation)
{
case PageRotation::None:
return PageRotation::None;
case PageRotation::Rotate90:
return PageRotation::Rotate270;
case PageRotation::Rotate180:
return PageRotation::Rotate180;
case PageRotation::Rotate270:
return PageRotation::Rotate90;
}
return PageRotation::None;
}
/// This class represents attributes, which are inheritable. Also allows merging from
/// parents.
class PDFPageInheritableAttributes
{
public:
explicit inline PDFPageInheritableAttributes() = default;
/// Parses inheritable attributes from the page tree node
/// \param templateAttributes Template attributes
/// \param dictionary Dictionary, from which the data will be read
/// \param storage Storage owning this data
static PDFPageInheritableAttributes parse(const PDFPageInheritableAttributes& templateAttributes, const PDFObject& dictionary, const PDFObjectStorage* storage);
const QRectF& getMediaBox() const { return m_mediaBox; }
const QRectF& getCropBox() const { return m_cropBox; }
PageRotation getPageRotation() const;
const PDFObject& getResources() const { return m_resources; }
private:
QRectF m_mediaBox;
QRectF m_cropBox;
std::optional<PageRotation> m_pageRotation;
PDFObject m_resources;
};
/// Object representing page in PDF document. Contains different page properties, such as
/// media box, crop box, rotation, etc. and also page content, resources.
class PDF4QTLIBSHARED_EXPORT PDFPage
{
public:
explicit PDFPage() = default;
/// Parses the page tree. If error occurs, then exception is thrown.
/// \param storage Storage owning this tree
/// \param root Root object of page tree
static std::vector<PDFPage> parse(const PDFObjectStorage* storage, const PDFObject& root);
inline const QRectF& getMediaBox() const { return m_mediaBox; }
inline const QRectF& getCropBox() const { return m_cropBox; }
inline const QRectF& getBleedBox() const { return m_bleedBox; }
inline const QRectF& getTrimBox() const { return m_trimBox; }
inline const QRectF& getArtBox() const { return m_artBox; }
inline PageRotation getPageRotation() const { return m_pageRotation; }
inline const PDFObject& getResources() const { return m_resources; }
inline const PDFObject& getContents() const { return m_contents; }
QRectF getRectMM(const QRectF& rect) const;
inline QRectF getMediaBoxMM() const { return getRectMM(m_mediaBox); }
inline QRectF getCropBoxMM() const { return getRectMM(m_cropBox); }
inline QRectF getBleedBoxMM() const { return getRectMM(m_bleedBox); }
inline QRectF getTrimBoxMM() const { return getRectMM(m_trimBox); }
inline QRectF getArtBoxMM() const { return getRectMM(m_artBox); }
inline PDFObjectReference getPageReference() const { return m_pageReference; }
inline PDFObjectReference getThumbnailReference() const { return m_thumbnailReference; }
inline PDFObjectReference getDocumentPart() const { return m_documentPart; }
QRectF getRotatedMediaBox() const;
QRectF getRotatedMediaBoxMM() const;
QRectF getRotatedCropBox() const;
inline const std::vector<PDFObjectReference>& getAnnotations() const { return m_annots; }
inline const std::vector<PDFObjectReference>& getBeads() const { return m_beads; }
inline const QDateTime& getLastModifiedDateTime() const { return m_lastModified; }
/// Returns box color info dictionary, if it is present. This dictionary
/// describes appearance of page boundaries. Empty object can be returned,
/// if dictionary doesn't exist.
/// \param storage Storage
PDFObject getBoxColorInfo(const PDFObjectStorage* storage) const;
/// Returns page transparency group (attributes for the
/// transparent imaging model). Empty object can be returned,
/// if dictionary doesn't exist.
/// \param storage Storage
PDFObject getTransparencyGroup(const PDFObjectStorage* storage) const;
/// Returns page thumbnail. Empty object can be returned,
/// if thumbnail doesn't exist.
/// \param storage Storage
PDFObject getThumbnail(const PDFObjectStorage* storage) const;
/// Returns page transition. Page transition object defines,
/// what should be done during presentations, how pages are switched etc.
/// Empty object can be returned, if thumbnail doesn't exist.
/// \param storage Storage
PDFObject getTransition(const PDFObjectStorage* storage) const;
/// Returns page additional actions dictionary. If no additional
/// actions are defined, then empty object is returned.
/// \param storage Storage
PDFObject getAdditionalActions(const PDFObjectStorage* storage) const;
/// Returns page metadata stream. If no metadata stream is defined,
/// then empty object is returned.
/// \param storage Storage
PDFObject getMetadata(const PDFObjectStorage* storage) const;
/// Returns page piece dictionary associated with the page.
/// Empty object can be returned, if no piece dictionary is found.
/// \param storage Storage
PDFObject getPieceDictionary(const PDFObjectStorage* storage) const;
/// Returns color separation info. This information is required
/// to generate color separations for the page.
/// \param storage Storage
PDFObject getColorSeparationInfo(const PDFObjectStorage* storage) const;
/// Returns first navigation node on the page, or null object,
/// if no navigation nodes are present.
/// \param storage Storage
PDFObject getFirstSubpageNavigationNode(const PDFObjectStorage* storage) const;
/// Returns array of viewport dictionaries, that shall specify
/// rectangular regions on the page.
/// \param storage Storage
PDFObject getViewports(const PDFObjectStorage* storage) const;
/// Returns array of associated files.
/// \param storage Storage
PDFObject getAssociatedFiles(const PDFObjectStorage* storage) const;
/// Returns array of output intents. Output intents define color
/// characteristics of output devices on which this page
/// will be rendered.
/// \param storage Storage
PDFObject getOutputIntents(const PDFObjectStorage* storage) const;
/// Returns page transition time. During presentations, this specifies a time window,
/// in which is page displayed, until it is advanced to the next page. Time
/// is specified in seconds.
inline PDFInteger getDuration() const { return m_duration; }
/// Returns integer key of structure parent of the page, in the structure tree.
/// If no structure tree exists, or page doesn't define it, then zero is returned.
inline PDFInteger getStructureParentKey() const { return m_structParent; }
/// Returns web capture content set id.
inline const QByteArray& getWebCaptureContentSetId() const { return m_webCaptureContentSetId; }
/// Returns preferred zoom. If zero is returned, no preferred zoom is returned.
inline PDFReal getPreferredZoom() const { return m_preferredZoom; }
/// Returns page tab order (if it is defined). Page tab order defines
/// sequence of tab stops for annotations. If no tab order is defined,
/// then Invalid is returned.
inline PageTabOrder getTabOrder() const { return m_pageTabOrder; }
/// Returns name of template, from which this page was generated
inline const QByteArray& getTemplateName() const { return m_templateName; }
/// Returns page user space unit. User space units are multiplies
/// of 1 / 72 inch. Default value is 1.0.
inline PDFReal getUserUnit() const { return m_userUnit; }
static QSizeF getRotatedSize(const QSizeF& size, PageRotation rotation);
static QRectF getRotatedBox(const QRectF& rect, PageRotation rotation);
private:
/// Parses the page tree (implementation). If error occurs, then exception is thrown.
/// \param pages Page array. Pages are inserted into this array
/// \param visitedReferences Visited references (to check cycles in page tree and avoid hangup)
/// \param templateAttributes Template attributes (inheritable attributes defined in parent)
/// \param root Root object of page tree
/// \param storage Storage owning this tree
static void parseImpl(std::vector<PDFPage>& pages,
std::set<PDFObjectReference>& visitedReferences,
const PDFPageInheritableAttributes& templateAttributes,
const PDFObject& root,
const PDFObjectStorage* storage);
/// Returns object from page dictionary. This function requires,
/// that storage of object is present, for object fetching. Objects
/// are not stored in this class, because it will have too large
/// memory requirements.
/// \param storage Storage
/// \param key Page dictionary key
PDFObject getObjectFromPageDictionary(const PDFObjectStorage* storage, const char* key) const;
PDFObject m_pageObject;
QRectF m_mediaBox;
QRectF m_cropBox;
QRectF m_bleedBox;
QRectF m_trimBox;
QRectF m_artBox;
PageRotation m_pageRotation = PageRotation::None;
PDFObject m_resources;
PDFObject m_contents;
PDFObjectReference m_pageReference;
PDFObjectReference m_thumbnailReference;
PDFObjectReference m_documentPart;
std::vector<PDFObjectReference> m_annots;
std::vector<PDFObjectReference> m_beads;
QDateTime m_lastModified;
PDFInteger m_duration = 0;
PDFInteger m_structParent = 0;
PDFReal m_preferredZoom = 0.0;
PDFReal m_userUnit = 1.0;
PageTabOrder m_pageTabOrder = PageTabOrder::Invalid;
QByteArray m_webCaptureContentSetId;
QByteArray m_templateName;
};
} // namespace pdf
#endif // PDFPAGE_H