src/pdf/SkPDFDevice.h - skia - Git at Google

 /*
  * Copyright 2011 Google Inc.
  *
  * Use of this source code is governed by a BSD-style license that can be
  * found in the LICENSE file.
  */

 #ifndef SkPDFDevice_DEFINED
 #define SkPDFDevice_DEFINED

 #include "SkBitmap.h"
 #include "SkCanvas.h"
 #include "SkClipStack.h"
 #include "SkClipStackDevice.h"
 #include "SkData.h"
 #include "SkPaint.h"
 #include "SkRect.h"
 #include "SkRefCnt.h"
 #include "SkSinglyLinkedList.h"
 #include "SkStream.h"
 #include "SkTDArray.h"
 #include "SkTextBlob.h"
 #include "SkKeyedImage.h"

 class SkKeyedImage;
 class SkPath;
 class SkPDFArray;
 class SkPDFCanon;
 class SkPDFDevice;
 class SkPDFDocument;
 class SkPDFDict;
 class SkPDFFont;
 class SkPDFObject;
 class SkPDFStream;
 class SkRRect;

 /**
  *  \class SkPDFDevice
  *
  *  An SkPDFDevice is the drawing context for a page or layer of PDF
  *  content.
  */
 class SkPDFDevice final : public SkClipStackDevice {
 public:
     /**
      *  @param pageSize Page size in point units.
      *         1 point == 127/360 mm == 1/72 inch
      *  @param document  A non-null pointer back to the
      *         PDFDocument object.  The document is repsonsible for
      *         de-duplicating across pages (via the SkPDFCanon) and
      *         for early serializing of large immutable objects, such
      *         as images (via SkPDFDocument::serialize()).
      */
     SkPDFDevice(SkISize pageSize, SkPDFDocument* document);

     /**
      *  Apply a scale-and-translate transform to move the origin from the
      *  bottom left (PDF default) to the top left (Skia default).
      */
     void setFlip();

     sk_sp<SkPDFDevice> makeCongruentDevice() {
         return sk_make_sp<SkPDFDevice>(fPageSize, fDocument);
     }

     ~SkPDFDevice() override;

     /**
      *  These are called inside the per-device-layer loop for each draw call.
      *  When these are called, we have already applied any saveLayer
      *  operations, and are handling any looping from the paint, and any
      *  effects from the DrawFilter.
      */
     void drawPaint(const SkPaint& paint) override;
     void drawPoints(SkCanvas::PointMode mode,
                     size_t count, const SkPoint[],
                     const SkPaint& paint) override;
     void drawRect(const SkRect& r, const SkPaint& paint) override;
     void drawOval(const SkRect& oval, const SkPaint& paint) override;
     void drawRRect(const SkRRect& rr, const SkPaint& paint) override;
     void drawPath(const SkPath& origpath,
                   const SkPaint& paint, const SkMatrix* prePathMatrix,
                   bool pathIsMutable) override;
     void drawBitmapRect(const SkBitmap& bitmap, const SkRect* src,
                         const SkRect& dst, const SkPaint&, SkCanvas::SrcRectConstraint) override;
     void drawBitmap(const SkBitmap& bitmap, SkScalar x, SkScalar y, const SkPaint&) override;
     void drawSprite(const SkBitmap& bitmap, int x, int y,
                     const SkPaint& paint) override;
     void drawImage(const SkImage*,
                    SkScalar x,
                    SkScalar y,
                    const SkPaint&) override;
     void drawImageRect(const SkImage*,
                        const SkRect* src,
                        const SkRect& dst,
                        const SkPaint&,
                        SkCanvas::SrcRectConstraint) override;
     void drawText(const void* text, size_t len,
                   SkScalar x, SkScalar y, const SkPaint&) override;
     void drawPosText(const void* text, size_t len,
                      const SkScalar pos[], int scalarsPerPos,
                      const SkPoint& offset, const SkPaint&) override;
     void drawTextBlob(const SkTextBlob*, SkScalar x, SkScalar y,
                       const SkPaint &, SkDrawFilter*) override;
     void drawVertices(const SkVertices*, SkBlendMode, const SkPaint&) override;
     void drawDevice(SkBaseDevice*, int x, int y,
                     const SkPaint&) override;

     // PDF specific methods.

     /** Create the resource dictionary for this device. */
     sk_sp<SkPDFDict> makeResourceDict() const;

     /** Add our annotations (link to urls and destinations) to the supplied
      *  array.
      *  @param array Array to add annotations to.
      */
     void appendAnnotations(SkPDFArray* array) const;

     /** Add our named destinations to the supplied dictionary.
      *  @param dict  Dictionary to add destinations to.
      *  @param page  The PDF object representing the page for this device.
      */
     void appendDestinations(SkPDFDict* dict, SkPDFObject* page) const;

     /** Returns a copy of the media box for this device. */
     sk_sp<SkPDFArray> copyMediaBox() const;

     /** Returns a SkStream with the page contents.
      */
     std::unique_ptr<SkStreamAsset> content() const;

     SkPDFCanon* getCanon() const;

     SkIRect bounds() const { return this->imageInfo().bounds(); }

     // It is important to not confuse GraphicStateEntry with SkPDFGraphicState, the
     // later being our representation of an object in the PDF file.
     struct GraphicStateEntry {
         GraphicStateEntry();

         // Compare the fields we care about when setting up a new content entry.
         bool compareInitialState(const GraphicStateEntry& b);

         SkMatrix fMatrix;
         // We can't do set operations on Paths, though PDF natively supports
         // intersect.  If the clip stack does anything other than intersect,
         // we have to fall back to the region.  Treat fClipStack as authoritative.
         // See https://bugs.skia.org/221
         SkClipStack fClipStack;

         // When emitting the content entry, we will ensure the graphic state
         // is set to these values first.
         SkColor fColor;
         SkScalar fTextScaleX;  // Zero means we don't care what the value is.
         SkPaint::Style fTextFill;  // Only if TextScaleX is non-zero.
         int fShaderIndex;
         int fGraphicStateIndex;
     };

 protected:
     sk_sp<SkSurface> makeSurface(const SkImageInfo&, const SkSurfaceProps&) override;

     void drawAnnotation(const SkRect&, const char key[], SkData* value) override;

     void drawSpecial(SkSpecialImage*, int x, int y, const SkPaint&,
                      SkImage*, const SkMatrix&) override;
     sk_sp<SkSpecialImage> makeSpecial(const SkBitmap&) override;
     sk_sp<SkSpecialImage> makeSpecial(const SkImage*) override;
     sk_sp<SkSpecialImage> snapSpecial() override;
     SkImageFilterCache* getImageFilterCache() override;

 private:
     struct RectWithData {
         SkRect rect;
         sk_sp<SkData> data;
     };

     struct NamedDestination {
         sk_sp<SkData> nameData;
         SkPoint point;
     };

     // TODO(vandebo): push most of SkPDFDevice's state into a core object in
     // order to get the right access levels without using friend.
     friend class ScopedContentEntry;

     SkISize fPageSize;
     SkMatrix fInitialTransform;
     SkClipStack fExistingClipStack;

     SkTArray<RectWithData> fLinkToURLs;
     SkTArray<RectWithData> fLinkToDestinations;
     SkTArray<NamedDestination> fNamedDestinations;

     SkTDArray<SkPDFObject*> fGraphicStateResources;
     SkTDArray<SkPDFObject*> fXObjectResources;
     SkTDArray<SkPDFFont*> fFontResources;
     SkTDArray<SkPDFObject*> fShaderResources;

     struct ContentEntry {
         GraphicStateEntry fState;
         SkDynamicMemoryWStream fContent;
     };
     SkSinglyLinkedList<ContentEntry> fContentEntries;

     SkPDFDocument* fDocument;

     ////////////////////////////////////////////////////////////////////////////

     SkBaseDevice* onCreateDevice(const CreateInfo&, const SkPaint*) override;

     void init();
     void cleanUp();
     // Set alpha to true if making a transparency group form x-objects.
     sk_sp<SkPDFObject> makeFormXObjectFromDevice(bool alpha = false);

     void drawFormXObjectWithMask(int xObjectIndex,
                                  sk_sp<SkPDFObject> mask,
                                  const SkClipStack& clipStack,
                                  SkBlendMode,
                                  bool invertClip);

     // If the paint or clip is such that we shouldn't draw anything, this
     // returns nullptr and does not create a content entry.
     // setUpContentEntry and finishContentEntry can be used directly, but
     // the preferred method is to use the ScopedContentEntry helper class.
     ContentEntry* setUpContentEntry(const SkClipStack& clipStack,
                                     const SkMatrix& matrix,
                                     const SkPaint& paint,
                                     bool hasText,
                                     sk_sp<SkPDFObject>* dst);
     void finishContentEntry(SkBlendMode, sk_sp<SkPDFObject> dst, SkPath* shape);
     bool isContentEmpty();

     void populateGraphicStateEntryFromPaint(const SkMatrix& matrix,
                                             const SkClipStack& clipStack,
                                             const SkPaint& paint,
                                             bool hasText,
                                             GraphicStateEntry* entry);
     int addGraphicStateResource(SkPDFObject* gs);
     int addXObjectResource(SkPDFObject* xObject);

     int getFontResourceIndex(SkTypeface* typeface, uint16_t glyphID);


     void internalDrawText( const void*, size_t, const SkScalar pos[],
                           SkTextBlob::GlyphPositioning, SkPoint, const SkPaint&,
                           const uint32_t*, uint32_t, const char*);

     void internalDrawPaint(const SkPaint& paint, ContentEntry* contentEntry);

     void internalDrawImageRect(SkKeyedImage,
                                const SkRect* src,
                                const SkRect& dst,
                                const SkPaint&,
                                const SkMatrix& canvasTransformationMatrix);

     void internalDrawPath(const SkClipStack&,
                           const SkMatrix&,
                           const SkPath&,
                           const SkPaint&,
                           const SkMatrix* prePathMatrix,
                           bool pathIsMutable);

     void internalDrawPathWithFilter(const SkClipStack& clipStack,
                                     const SkMatrix& ctm,
                                     const SkPath& origPath,
                                     const SkPaint& paint,
                                     const SkMatrix* prePathMatrix);

     bool handleInversePath(const SkPath& origPath,
                            const SkPaint& paint, bool pathIsMutable,
                            const SkMatrix* prePathMatrix = nullptr);

     void addSMaskGraphicState(sk_sp<SkPDFDevice> maskDevice, SkDynamicMemoryWStream*);
     void clearMaskOnGraphicState(SkDynamicMemoryWStream*);

     bool hasEmptyClip() const { return this->cs().isEmpty(this->bounds()); }

     typedef SkClipStackDevice INHERITED;
 };

 #endif
	/*
	* Copyright 2011 Google Inc.
	*
	* Use of this source code is governed by a BSD-style license that can be
	* found in the LICENSE file.
	*/

	#ifndef SkPDFDevice_DEFINED
	#define SkPDFDevice_DEFINED

	#include "SkBitmap.h"
	#include "SkCanvas.h"
	#include "SkClipStack.h"
	#include "SkClipStackDevice.h"
	#include "SkData.h"
	#include "SkPaint.h"
	#include "SkRect.h"
	#include "SkRefCnt.h"
	#include "SkSinglyLinkedList.h"
	#include "SkStream.h"
	#include "SkTDArray.h"
	#include "SkTextBlob.h"
	#include "SkKeyedImage.h"

	class SkKeyedImage;
	class SkPath;
	class SkPDFArray;
	class SkPDFCanon;
	class SkPDFDevice;
	class SkPDFDocument;
	class SkPDFDict;
	class SkPDFFont;
	class SkPDFObject;
	class SkPDFStream;
	class SkRRect;

	/**
	* \class SkPDFDevice
	*
	* An SkPDFDevice is the drawing context for a page or layer of PDF
	* content.
	*/
	class SkPDFDevice final : public SkClipStackDevice {
	public:
	/**
	* @param pageSize Page size in point units.
	* 1 point == 127/360 mm == 1/72 inch
	* @param document A non-null pointer back to the
	* PDFDocument object. The document is repsonsible for
	* de-duplicating across pages (via the SkPDFCanon) and
	* for early serializing of large immutable objects, such
	* as images (via SkPDFDocument::serialize()).
	*/
	SkPDFDevice(SkISize pageSize, SkPDFDocument* document);

	/**
	* Apply a scale-and-translate transform to move the origin from the
	* bottom left (PDF default) to the top left (Skia default).
	*/
	void setFlip();

	sk_sp<SkPDFDevice> makeCongruentDevice() {
	return sk_make_sp<SkPDFDevice>(fPageSize, fDocument);
	}

	~SkPDFDevice() override;

	/**
	* These are called inside the per-device-layer loop for each draw call.
	* When these are called, we have already applied any saveLayer
	* operations, and are handling any looping from the paint, and any
	* effects from the DrawFilter.
	*/
	void drawPaint(const SkPaint& paint) override;
	void drawPoints(SkCanvas::PointMode mode,
	size_t count, const SkPoint[],
	const SkPaint& paint) override;
	void drawRect(const SkRect& r, const SkPaint& paint) override;
	void drawOval(const SkRect& oval, const SkPaint& paint) override;
	void drawRRect(const SkRRect& rr, const SkPaint& paint) override;
	void drawPath(const SkPath& origpath,
	const SkPaint& paint, const SkMatrix* prePathMatrix,
	bool pathIsMutable) override;
	void drawBitmapRect(const SkBitmap& bitmap, const SkRect* src,
	const SkRect& dst, const SkPaint&, SkCanvas::SrcRectConstraint) override;
	void drawBitmap(const SkBitmap& bitmap, SkScalar x, SkScalar y, const SkPaint&) override;
	void drawSprite(const SkBitmap& bitmap, int x, int y,
	const SkPaint& paint) override;
	void drawImage(const SkImage*,
	SkScalar x,
	SkScalar y,
	const SkPaint&) override;
	void drawImageRect(const SkImage*,
	const SkRect* src,
	const SkRect& dst,
	const SkPaint&,
	SkCanvas::SrcRectConstraint) override;
	void drawText(const void* text, size_t len,
	SkScalar x, SkScalar y, const SkPaint&) override;
	void drawPosText(const void* text, size_t len,
	const SkScalar pos[], int scalarsPerPos,
	const SkPoint& offset, const SkPaint&) override;
	void drawTextBlob(const SkTextBlob*, SkScalar x, SkScalar y,
	const SkPaint &, SkDrawFilter*) override;
	void drawVertices(const SkVertices*, SkBlendMode, const SkPaint&) override;
	void drawDevice(SkBaseDevice*, int x, int y,
	const SkPaint&) override;

	// PDF specific methods.

	/** Create the resource dictionary for this device. */
	sk_sp<SkPDFDict> makeResourceDict() const;

	/** Add our annotations (link to urls and destinations) to the supplied
	* array.
	* @param array Array to add annotations to.
	*/
	void appendAnnotations(SkPDFArray* array) const;

	/** Add our named destinations to the supplied dictionary.
	* @param dict Dictionary to add destinations to.
	* @param page The PDF object representing the page for this device.
	*/
	void appendDestinations(SkPDFDict* dict, SkPDFObject* page) const;

	/** Returns a copy of the media box for this device. */
	sk_sp<SkPDFArray> copyMediaBox() const;

	/** Returns a SkStream with the page contents.
	*/
	std::unique_ptr<SkStreamAsset> content() const;

	SkPDFCanon* getCanon() const;

	SkIRect bounds() const { return this->imageInfo().bounds(); }

	// It is important to not confuse GraphicStateEntry with SkPDFGraphicState, the
	// later being our representation of an object in the PDF file.
	struct GraphicStateEntry {
	GraphicStateEntry();

	// Compare the fields we care about when setting up a new content entry.
	bool compareInitialState(const GraphicStateEntry& b);

	SkMatrix fMatrix;
	// We can't do set operations on Paths, though PDF natively supports
	// intersect. If the clip stack does anything other than intersect,
	// we have to fall back to the region. Treat fClipStack as authoritative.
	// See https://bugs.skia.org/221
	SkClipStack fClipStack;

	// When emitting the content entry, we will ensure the graphic state
	// is set to these values first.
	SkColor fColor;
	SkScalar fTextScaleX; // Zero means we don't care what the value is.
	SkPaint::Style fTextFill; // Only if TextScaleX is non-zero.
	int fShaderIndex;
	int fGraphicStateIndex;
	};

	protected:
	sk_sp<SkSurface> makeSurface(const SkImageInfo&, const SkSurfaceProps&) override;

	void drawAnnotation(const SkRect&, const char key[], SkData* value) override;

	void drawSpecial(SkSpecialImage*, int x, int y, const SkPaint&,
	SkImage*, const SkMatrix&) override;
	sk_sp<SkSpecialImage> makeSpecial(const SkBitmap&) override;
	sk_sp<SkSpecialImage> makeSpecial(const SkImage*) override;
	sk_sp<SkSpecialImage> snapSpecial() override;
	SkImageFilterCache* getImageFilterCache() override;

	private:
	struct RectWithData {
	SkRect rect;
	sk_sp<SkData> data;
	};

	struct NamedDestination {
	sk_sp<SkData> nameData;
	SkPoint point;
	};

	// TODO(vandebo): push most of SkPDFDevice's state into a core object in
	// order to get the right access levels without using friend.
	friend class ScopedContentEntry;

	SkISize fPageSize;
	SkMatrix fInitialTransform;
	SkClipStack fExistingClipStack;

	SkTArray<RectWithData> fLinkToURLs;
	SkTArray<RectWithData> fLinkToDestinations;
	SkTArray<NamedDestination> fNamedDestinations;

	SkTDArray<SkPDFObject*> fGraphicStateResources;
	SkTDArray<SkPDFObject*> fXObjectResources;
	SkTDArray<SkPDFFont*> fFontResources;
	SkTDArray<SkPDFObject*> fShaderResources;

	struct ContentEntry {
	GraphicStateEntry fState;
	SkDynamicMemoryWStream fContent;
	};
	SkSinglyLinkedList<ContentEntry> fContentEntries;

	SkPDFDocument* fDocument;

	////////////////////////////////////////////////////////////////////////////

	SkBaseDevice* onCreateDevice(const CreateInfo&, const SkPaint*) override;

	void init();
	void cleanUp();
	// Set alpha to true if making a transparency group form x-objects.
	sk_sp<SkPDFObject> makeFormXObjectFromDevice(bool alpha = false);

	void drawFormXObjectWithMask(int xObjectIndex,
	sk_sp<SkPDFObject> mask,
	const SkClipStack& clipStack,
	SkBlendMode,
	bool invertClip);

	// If the paint or clip is such that we shouldn't draw anything, this
	// returns nullptr and does not create a content entry.
	// setUpContentEntry and finishContentEntry can be used directly, but
	// the preferred method is to use the ScopedContentEntry helper class.
	ContentEntry* setUpContentEntry(const SkClipStack& clipStack,
	const SkMatrix& matrix,
	const SkPaint& paint,
	bool hasText,
	sk_sp<SkPDFObject>* dst);
	void finishContentEntry(SkBlendMode, sk_sp<SkPDFObject> dst, SkPath* shape);
	bool isContentEmpty();

	void populateGraphicStateEntryFromPaint(const SkMatrix& matrix,
	const SkClipStack& clipStack,
	const SkPaint& paint,
	bool hasText,
	GraphicStateEntry* entry);
	int addGraphicStateResource(SkPDFObject* gs);
	int addXObjectResource(SkPDFObject* xObject);

	int getFontResourceIndex(SkTypeface* typeface, uint16_t glyphID);


	void internalDrawText( const void*, size_t, const SkScalar pos[],
	SkTextBlob::GlyphPositioning, SkPoint, const SkPaint&,
	const uint32_t, uint32_t, const char);

	void internalDrawPaint(const SkPaint& paint, ContentEntry* contentEntry);

	void internalDrawImageRect(SkKeyedImage,
	const SkRect* src,
	const SkRect& dst,
	const SkPaint&,
	const SkMatrix& canvasTransformationMatrix);

	void internalDrawPath(const SkClipStack&,
	const SkMatrix&,
	const SkPath&,
	const SkPaint&,
	const SkMatrix* prePathMatrix,
	bool pathIsMutable);

	void internalDrawPathWithFilter(const SkClipStack& clipStack,
	const SkMatrix& ctm,
	const SkPath& origPath,
	const SkPaint& paint,
	const SkMatrix* prePathMatrix);

	bool handleInversePath(const SkPath& origPath,
	const SkPaint& paint, bool pathIsMutable,
	const SkMatrix* prePathMatrix = nullptr);

	void addSMaskGraphicState(sk_sp<SkPDFDevice> maskDevice, SkDynamicMemoryWStream*);
	void clearMaskOnGraphicState(SkDynamicMemoryWStream*);

	bool hasEmptyClip() const { return this->cs().isEmpty(this->bounds()); }

	typedef SkClipStackDevice INHERITED;
	};

	#endif