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/*
* 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 SkPDFFont_DEFINED
#define SkPDFFont_DEFINED
#include "SkAdvancedTypefaceMetrics.h"
#include "SkBitSet.h"
#include "SkPDFTypes.h"
#include "SkTDArray.h"
#include "SkTypeface.h"
class SkAutoGlyphCache;
class SkPDFCanon;
class SkPDFFont;
/** \class SkPDFFont
A PDF Object class representing a font. The font may have resources
attached to it in order to embed the font. SkPDFFonts are canonicalized
so that resource deduplication will only include one copy of a font.
This class uses the same pattern as SkPDFGraphicState, a static weak
reference to each instantiated class.
*/
class SkPDFFont : public SkPDFDict {
public:
~SkPDFFont() override;
/** Returns the typeface represented by this class. Returns nullptr for the
* default typeface.
*/
SkTypeface* typeface() const { return fTypeface.get(); }
/** Returns the font type represented in this font. For Type0 fonts,
* returns the type of the decendant font.
*/
SkAdvancedTypefaceMetrics::FontType getType() const { return fFontType; }
static SkAdvancedTypefaceMetrics::FontType FontType(const SkAdvancedTypefaceMetrics&);
static bool IsMultiByte(SkAdvancedTypefaceMetrics::FontType type) {
return type == SkAdvancedTypefaceMetrics::kType1CID_Font ||
type == SkAdvancedTypefaceMetrics::kTrueType_Font;
}
static SkAutoGlyphCache MakeVectorCache(SkTypeface*, int* sizeOut);
/** Returns true if this font encoding supports glyph IDs above 255.
*/
bool multiByteGlyphs() const { return SkPDFFont::IsMultiByte(this->getType()); }
/** Return true if this font has an encoding for the passed glyph id.
*/
bool hasGlyph(SkGlyphID gid) {
return (gid >= fFirstGlyphID && gid <= fLastGlyphID) || gid == 0;
}
/** Convert the input glyph ID into the font encoding. */
SkGlyphID glyphToPDFFontEncoding(SkGlyphID gid) const {
if (this->multiByteGlyphs() || gid == 0) {
return gid;
}
SkASSERT(gid >= fFirstGlyphID && gid <= fLastGlyphID);
SkASSERT(fFirstGlyphID > 0);
return gid - fFirstGlyphID + 1;
}
void noteGlyphUsage(SkGlyphID glyph) {
SkASSERT(this->hasGlyph(glyph));
fGlyphUsage.set(glyph);
}
/** Get the font resource for the passed typeface and glyphID. The
* reference count of the object is incremented and it is the caller's
* responsibility to unreference it when done. This is needed to
* accommodate the weak reference pattern used when the returned object
* is new and has no other references.
* @param typeface The typeface to find, not nullptr.
* @param glyphID Specify which section of a large font is of interest.
*/
static sk_sp<SkPDFFont> GetFontResource(SkPDFCanon* canon,
SkTypeface* typeface,
SkGlyphID glyphID);
/** Gets SkAdvancedTypefaceMetrics, and caches the result.
* @param typeface can not be nullptr.
* @return nullptr only when typeface is bad.
*/
static const SkAdvancedTypefaceMetrics* GetMetrics(SkTypeface* typeface,
SkPDFCanon* canon);
/** Subset the font based on current usage.
* Must be called before emitObject().
*/
virtual void getFontSubset(SkPDFCanon*) = 0;
/**
* Return false iff the typeface has its NotEmbeddable flag set.
* typeface is not nullptr
*/
static bool CanEmbedTypeface(SkTypeface*, SkPDFCanon*);
protected:
// Common constructor to handle common members.
struct Info {
sk_sp<SkTypeface> fTypeface;
SkGlyphID fFirstGlyphID;
SkGlyphID fLastGlyphID;
SkAdvancedTypefaceMetrics::FontType fFontType;
};
SkPDFFont(Info);
SkGlyphID firstGlyphID() const { return fFirstGlyphID; }
SkGlyphID lastGlyphID() const { return fLastGlyphID; }
const SkBitSet& glyphUsage() const { return fGlyphUsage; }
sk_sp<SkTypeface> refTypeface() const { return fTypeface; }
void drop() override;
private:
sk_sp<SkTypeface> fTypeface;
SkBitSet fGlyphUsage;
// The glyph IDs accessible with this font. For Type1 (non CID) fonts,
// this will be a subset if the font has more than 255 glyphs.
const SkGlyphID fFirstGlyphID;
const SkGlyphID fLastGlyphID;
const SkAdvancedTypefaceMetrics::FontType fFontType;
typedef SkPDFDict INHERITED;
};
#endif