| /* |
| * Copyright 2011 Google Inc. |
| * |
| * Use of this source code is governed by a BSD-style license that can be |
| * found in the LICENSE file. |
| */ |
| |
| #include "SkData.h" |
| #include "SkGlyphCache.h" |
| #include "SkMakeUnique.h" |
| #include "SkPDFCanon.h" |
| #include "SkPDFConvertType1FontStream.h" |
| #include "SkPDFDevice.h" |
| #include "SkPDFFont.h" |
| #include "SkPDFMakeCIDGlyphWidthsArray.h" |
| #include "SkPDFMakeToUnicodeCmap.h" |
| #include "SkPDFUtils.h" |
| #include "SkPaint.h" |
| #include "SkRefCnt.h" |
| #include "SkScalar.h" |
| #include "SkStream.h" |
| #include "SkTypes.h" |
| #include "SkUtils.h" |
| |
| #ifdef SK_PDF_USE_SFNTLY |
| #include "sample/chromium/font_subsetter.h" |
| #endif |
| |
| SkAutoGlyphCache SkPDFFont::MakeVectorCache(SkTypeface* face, int* size) { |
| SkPaint tmpPaint; |
| tmpPaint.setHinting(SkPaint::kNo_Hinting); |
| tmpPaint.setTypeface(sk_ref_sp(face)); |
| int unitsPerEm = face->getUnitsPerEm(); |
| if (unitsPerEm <= 0) { |
| unitsPerEm = 1024; |
| } |
| if (size) { |
| *size = unitsPerEm; |
| } |
| tmpPaint.setTextSize((SkScalar)unitsPerEm); |
| const SkSurfaceProps props(0, kUnknown_SkPixelGeometry); |
| SkAutoGlyphCache glyphCache(tmpPaint, &props, nullptr); |
| SkASSERT(glyphCache.get()); |
| return glyphCache; |
| } |
| |
| namespace { |
| // PDF's notion of symbolic vs non-symbolic is related to the character set, not |
| // symbols vs. characters. Rarely is a font the right character set to call it |
| // non-symbolic, so always call it symbolic. (PDF 1.4 spec, section 5.7.1) |
| static const int32_t kPdfSymbolic = 4; |
| |
| struct SkPDFType0Font final : public SkPDFFont { |
| SkPDFType0Font(SkPDFFont::Info, const SkAdvancedTypefaceMetrics&); |
| ~SkPDFType0Font() override; |
| void getFontSubset(SkPDFCanon*) override; |
| #ifdef SK_DEBUG |
| void emitObject(SkWStream*, const SkPDFObjNumMap&) const override; |
| bool fPopulated; |
| #endif |
| typedef SkPDFDict INHERITED; |
| }; |
| |
| struct SkPDFType1Font final : public SkPDFFont { |
| SkPDFType1Font(SkPDFFont::Info, const SkAdvancedTypefaceMetrics&, SkPDFCanon*); |
| ~SkPDFType1Font() override {} |
| void getFontSubset(SkPDFCanon*) override {} // TODO(halcanary): implement |
| }; |
| |
| struct SkPDFType3Font final : public SkPDFFont { |
| SkPDFType3Font(SkPDFFont::Info, const SkAdvancedTypefaceMetrics&); |
| ~SkPDFType3Font() override {} |
| void getFontSubset(SkPDFCanon*) override; |
| }; |
| |
| /////////////////////////////////////////////////////////////////////////////// |
| // File-Local Functions |
| /////////////////////////////////////////////////////////////////////////////// |
| |
| // scale from em-units to base-1000, returning as a SkScalar |
| SkScalar from_font_units(SkScalar scaled, uint16_t emSize) { |
| if (emSize == 1000) { |
| return scaled; |
| } else { |
| return scaled * 1000 / emSize; |
| } |
| } |
| |
| SkScalar scaleFromFontUnits(int16_t val, uint16_t emSize) { |
| return from_font_units(SkIntToScalar(val), emSize); |
| } |
| |
| |
| void setGlyphWidthAndBoundingBox(SkScalar width, SkIRect box, |
| SkDynamicMemoryWStream* content) { |
| // Specify width and bounding box for the glyph. |
| SkPDFUtils::AppendScalar(width, content); |
| content->writeText(" 0 "); |
| content->writeDecAsText(box.fLeft); |
| content->writeText(" "); |
| content->writeDecAsText(box.fTop); |
| content->writeText(" "); |
| content->writeDecAsText(box.fRight); |
| content->writeText(" "); |
| content->writeDecAsText(box.fBottom); |
| content->writeText(" d1\n"); |
| } |
| |
| static sk_sp<SkPDFArray> makeFontBBox(SkIRect glyphBBox, uint16_t emSize) { |
| auto bbox = sk_make_sp<SkPDFArray>(); |
| bbox->reserve(4); |
| bbox->appendScalar(scaleFromFontUnits(glyphBBox.fLeft, emSize)); |
| bbox->appendScalar(scaleFromFontUnits(glyphBBox.fBottom, emSize)); |
| bbox->appendScalar(scaleFromFontUnits(glyphBBox.fRight, emSize)); |
| bbox->appendScalar(scaleFromFontUnits(glyphBBox.fTop, emSize)); |
| return bbox; |
| } |
| } // namespace |
| |
| /////////////////////////////////////////////////////////////////////////////// |
| // class SkPDFFont |
| /////////////////////////////////////////////////////////////////////////////// |
| |
| /* Font subset design: It would be nice to be able to subset fonts |
| * (particularly type 3 fonts), but it's a lot of work and not a priority. |
| * |
| * Resources are canonicalized and uniqueified by pointer so there has to be |
| * some additional state indicating which subset of the font is used. It |
| * must be maintained at the page granularity and then combined at the document |
| * granularity. a) change SkPDFFont to fill in its state on demand, kind of |
| * like SkPDFGraphicState. b) maintain a per font glyph usage class in each |
| * page/pdf device. c) in the document, retrieve the per font glyph usage |
| * from each page and combine it and ask for a resource with that subset. |
| */ |
| |
| SkPDFFont::~SkPDFFont() {} |
| |
| static bool can_embed(const SkAdvancedTypefaceMetrics& metrics) { |
| return !SkToBool(metrics.fFlags & SkAdvancedTypefaceMetrics::kNotEmbeddable_FontFlag); |
| } |
| |
| const SkAdvancedTypefaceMetrics* SkPDFFont::GetMetrics(SkTypeface* typeface, |
| SkPDFCanon* canon) { |
| SkASSERT(typeface); |
| SkFontID id = typeface->uniqueID(); |
| if (std::unique_ptr<SkAdvancedTypefaceMetrics>* ptr = canon->fTypefaceMetrics.find(id)) { |
| return ptr->get(); // canon retains ownership. |
| } |
| int count = typeface->countGlyphs(); |
| if (count <= 0 || count > 1 + SK_MaxU16) { |
| // Cache nullptr to skip this check. Use SkSafeUnref(). |
| canon->fTypefaceMetrics.set(id, nullptr); |
| return nullptr; |
| } |
| std::unique_ptr<SkAdvancedTypefaceMetrics> metrics = typeface->getAdvancedMetrics(); |
| if (!metrics) { |
| metrics = skstd::make_unique<SkAdvancedTypefaceMetrics>(); |
| } |
| |
| if (0 == metrics->fStemV || 0 == metrics->fCapHeight) { |
| SkPaint tmpPaint; |
| tmpPaint.setHinting(SkPaint::kNo_Hinting); |
| tmpPaint.setTypeface(sk_ref_sp(typeface)); |
| tmpPaint.setTextSize(1000); // glyph coordinate system |
| if (0 == metrics->fStemV) { |
| // Figure out a good guess for StemV - Min width of i, I, !, 1. |
| // This probably isn't very good with an italic font. |
| int16_t stemV = SHRT_MAX; |
| for (char c : {'i', 'I', '!', '1'}) { |
| SkRect bounds; |
| tmpPaint.measureText(&c, 1, &bounds); |
| stemV = SkTMin(stemV, SkToS16(SkScalarRoundToInt(bounds.width()))); |
| } |
| metrics->fStemV = stemV; |
| } |
| if (0 == metrics->fCapHeight) { |
| // Figure out a good guess for CapHeight: average the height of M and X. |
| SkScalar capHeight = 0; |
| for (char c : {'M', 'X'}) { |
| SkRect bounds; |
| tmpPaint.measureText(&c, 1, &bounds); |
| capHeight += bounds.height(); |
| } |
| metrics->fCapHeight = SkToS16(SkScalarRoundToInt(capHeight / 2)); |
| } |
| } |
| return canon->fTypefaceMetrics.set(id, std::move(metrics))->get(); |
| } |
| |
| SkAdvancedTypefaceMetrics::FontType SkPDFFont::FontType(const SkAdvancedTypefaceMetrics& metrics) { |
| if (SkToBool(metrics.fFlags & SkAdvancedTypefaceMetrics::kMultiMaster_FontFlag) || |
| SkToBool(metrics.fFlags & SkAdvancedTypefaceMetrics::kNotEmbeddable_FontFlag)) { |
| // force Type3 fallback. |
| return SkAdvancedTypefaceMetrics::kOther_Font; |
| } |
| return metrics.fType; |
| } |
| |
| static SkGlyphID first_nonzero_glyph_for_single_byte_encoding(SkGlyphID gid) { |
| return gid != 0 ? gid - (gid - 1) % 255 : 1; |
| } |
| |
| sk_sp<SkPDFFont> SkPDFFont::GetFontResource(SkPDFCanon* canon, |
| SkTypeface* face, |
| SkGlyphID glyphID) { |
| SkASSERT(canon); |
| SkASSERT(face); // All SkPDFDevice::internalDrawText ensures this. |
| const SkAdvancedTypefaceMetrics* fontMetrics = SkPDFFont::GetMetrics(face, canon); |
| SkASSERT(fontMetrics); // SkPDFDevice::internalDrawText ensures the typeface is good. |
| // GetMetrics only returns null to signify a bad typeface. |
| const SkAdvancedTypefaceMetrics& metrics = *fontMetrics; |
| SkAdvancedTypefaceMetrics::FontType type = SkPDFFont::FontType(metrics); |
| bool multibyte = SkPDFFont::IsMultiByte(type); |
| SkGlyphID subsetCode = multibyte ? 0 : first_nonzero_glyph_for_single_byte_encoding(glyphID); |
| uint64_t fontID = (SkTypeface::UniqueID(face) << 16) | subsetCode; |
| |
| if (sk_sp<SkPDFFont>* found = canon->fFontMap.find(fontID)) { |
| SkDEBUGCODE(SkPDFFont* foundFont = found->get()); |
| SkASSERT(foundFont && multibyte == foundFont->multiByteGlyphs()); |
| return *found; |
| } |
| |
| sk_sp<SkTypeface> typeface(sk_ref_sp(face)); |
| SkASSERT(typeface); |
| |
| SkGlyphID lastGlyph = SkToU16(typeface->countGlyphs() - 1); |
| |
| // should be caught by SkPDFDevice::internalDrawText |
| SkASSERT(glyphID <= lastGlyph); |
| |
| SkGlyphID firstNonZeroGlyph; |
| if (multibyte) { |
| firstNonZeroGlyph = 1; |
| } else { |
| firstNonZeroGlyph = subsetCode; |
| lastGlyph = SkToU16(SkTMin<int>((int)lastGlyph, 254 + (int)subsetCode)); |
| } |
| SkPDFFont::Info info = {std::move(typeface), firstNonZeroGlyph, lastGlyph, type}; |
| sk_sp<SkPDFFont> font; |
| switch (type) { |
| case SkAdvancedTypefaceMetrics::kType1CID_Font: |
| case SkAdvancedTypefaceMetrics::kTrueType_Font: |
| SkASSERT(multibyte); |
| font = sk_make_sp<SkPDFType0Font>(std::move(info), metrics); |
| break; |
| case SkAdvancedTypefaceMetrics::kType1_Font: |
| SkASSERT(!multibyte); |
| font = sk_make_sp<SkPDFType1Font>(std::move(info), metrics, canon); |
| break; |
| default: |
| SkASSERT(!multibyte); |
| // Type3 is our fallback font. |
| font = sk_make_sp<SkPDFType3Font>(std::move(info), metrics); |
| break; |
| } |
| canon->fFontMap.set(fontID, font); |
| return font; |
| } |
| |
| SkPDFFont::SkPDFFont(SkPDFFont::Info info) |
| : SkPDFDict("Font") |
| , fTypeface(std::move(info.fTypeface)) |
| , fGlyphUsage(info.fLastGlyphID + 1) // TODO(halcanary): Adjust mapping? |
| , fFirstGlyphID(info.fFirstGlyphID) |
| , fLastGlyphID(info.fLastGlyphID) |
| , fFontType(info.fFontType) { |
| SkASSERT(fTypeface); |
| } |
| |
| static void add_common_font_descriptor_entries(SkPDFDict* descriptor, |
| const SkAdvancedTypefaceMetrics& metrics, |
| uint16_t emSize, |
| int16_t defaultWidth) { |
| descriptor->insertName("FontName", metrics.fFontName); |
| descriptor->insertInt("Flags", (size_t)(metrics.fStyle | kPdfSymbolic)); |
| descriptor->insertScalar("Ascent", |
| scaleFromFontUnits(metrics.fAscent, emSize)); |
| descriptor->insertScalar("Descent", |
| scaleFromFontUnits(metrics.fDescent, emSize)); |
| descriptor->insertScalar("StemV", |
| scaleFromFontUnits(metrics.fStemV, emSize)); |
| descriptor->insertScalar("CapHeight", |
| scaleFromFontUnits(metrics.fCapHeight, emSize)); |
| descriptor->insertInt("ItalicAngle", metrics.fItalicAngle); |
| descriptor->insertObject( |
| "FontBBox", makeFontBBox(metrics.fBBox, emSize)); |
| if (defaultWidth > 0) { |
| descriptor->insertScalar("MissingWidth", |
| scaleFromFontUnits(defaultWidth, emSize)); |
| } |
| } |
| |
| /////////////////////////////////////////////////////////////////////////////// |
| // class SkPDFType0Font |
| /////////////////////////////////////////////////////////////////////////////// |
| |
| SkPDFType0Font::SkPDFType0Font( |
| SkPDFFont::Info info, |
| const SkAdvancedTypefaceMetrics& metrics) |
| : SkPDFFont(std::move(info)) { |
| SkDEBUGCODE(fPopulated = false); |
| } |
| |
| SkPDFType0Font::~SkPDFType0Font() {} |
| |
| |
| #ifdef SK_DEBUG |
| void SkPDFType0Font::emitObject(SkWStream* stream, |
| const SkPDFObjNumMap& objNumMap) const { |
| SkASSERT(fPopulated); |
| return INHERITED::emitObject(stream, objNumMap); |
| } |
| #endif |
| |
| #ifdef SK_PDF_USE_SFNTLY |
| // if possible, make no copy. |
| static sk_sp<SkData> stream_to_data(std::unique_ptr<SkStreamAsset> stream) { |
| SkASSERT(stream); |
| (void)stream->rewind(); |
| SkASSERT(stream->hasLength()); |
| size_t size = stream->getLength(); |
| if (const void* base = stream->getMemoryBase()) { |
| SkData::ReleaseProc proc = |
| [](const void*, void* ctx) { delete (SkStreamAsset*)ctx; }; |
| return SkData::MakeWithProc(base, size, proc, stream.release()); |
| } |
| return SkData::MakeFromStream(stream.get(), size); |
| } |
| |
| static sk_sp<SkPDFStream> get_subset_font_stream( |
| std::unique_ptr<SkStreamAsset> fontAsset, |
| const SkBitSet& glyphUsage, |
| const char* fontName, |
| int ttcIndex) { |
| // Generate glyph id array in format needed by sfntly. |
| // TODO(halcanary): sfntly should take a more compact format. |
| SkTDArray<unsigned> subset; |
| if (!glyphUsage.has(0)) { |
| subset.push(0); // Always include glyph 0. |
| } |
| glyphUsage.exportTo(&subset); |
| |
| unsigned char* subsetFont{nullptr}; |
| sk_sp<SkData> fontData(stream_to_data(std::move(fontAsset))); |
| #if defined(SK_BUILD_FOR_GOOGLE3) |
| // TODO(halcanary): update SK_BUILD_FOR_GOOGLE3 to newest version of Sfntly. |
| (void)ttcIndex; |
| int subsetFontSize = SfntlyWrapper::SubsetFont(fontName, |
| fontData->bytes(), |
| fontData->size(), |
| subset.begin(), |
| subset.count(), |
| &subsetFont); |
| #else |
| (void)fontName; |
| int subsetFontSize = SfntlyWrapper::SubsetFont(ttcIndex, |
| fontData->bytes(), |
| fontData->size(), |
| subset.begin(), |
| subset.count(), |
| &subsetFont); |
| #endif |
| fontData.reset(); |
| subset.reset(); |
| SkASSERT(subsetFontSize > 0 || subsetFont == nullptr); |
| if (subsetFontSize < 1) { |
| return nullptr; |
| } |
| SkASSERT(subsetFont != nullptr); |
| auto subsetStream = sk_make_sp<SkPDFStream>( |
| SkData::MakeWithProc( |
| subsetFont, subsetFontSize, |
| [](const void* p, void*) { delete[] (unsigned char*)p; }, |
| nullptr)); |
| subsetStream->dict()->insertInt("Length1", subsetFontSize); |
| return subsetStream; |
| } |
| #endif // SK_PDF_USE_SFNTLY |
| |
| void SkPDFType0Font::getFontSubset(SkPDFCanon* canon) { |
| const SkAdvancedTypefaceMetrics* metricsPtr = |
| SkPDFFont::GetMetrics(this->typeface(), canon); |
| SkASSERT(metricsPtr); |
| if (!metricsPtr) { return; } |
| const SkAdvancedTypefaceMetrics& metrics = *metricsPtr; |
| SkASSERT(can_embed(metrics)); |
| SkAdvancedTypefaceMetrics::FontType type = this->getType(); |
| SkTypeface* face = this->typeface(); |
| SkASSERT(face); |
| |
| auto descriptor = sk_make_sp<SkPDFDict>("FontDescriptor"); |
| uint16_t emSize = SkToU16(this->typeface()->getUnitsPerEm()); |
| add_common_font_descriptor_entries(descriptor.get(), metrics, emSize , 0); |
| |
| int ttcIndex; |
| std::unique_ptr<SkStreamAsset> fontAsset(face->openStream(&ttcIndex)); |
| size_t fontSize = fontAsset ? fontAsset->getLength() : 0; |
| if (0 == fontSize) { |
| SkDebugf("Error: (SkTypeface)(%p)::openStream() returned " |
| "empty stream (%p) when identified as kType1CID_Font " |
| "or kTrueType_Font.\n", face, fontAsset.get()); |
| } else { |
| switch (type) { |
| case SkAdvancedTypefaceMetrics::kTrueType_Font: { |
| #ifdef SK_PDF_USE_SFNTLY |
| if (!SkToBool(metrics.fFlags & |
| SkAdvancedTypefaceMetrics::kNotSubsettable_FontFlag)) { |
| sk_sp<SkPDFStream> subsetStream = get_subset_font_stream( |
| std::move(fontAsset), this->glyphUsage(), |
| metrics.fFontName.c_str(), ttcIndex); |
| if (subsetStream) { |
| descriptor->insertObjRef("FontFile2", std::move(subsetStream)); |
| break; |
| } |
| // If subsetting fails, fall back to original font data. |
| fontAsset.reset(face->openStream(&ttcIndex)); |
| SkASSERT(fontAsset); |
| SkASSERT(fontAsset->getLength() == fontSize); |
| if (!fontAsset || fontAsset->getLength() == 0) { break; } |
| } |
| #endif // SK_PDF_USE_SFNTLY |
| auto fontStream = sk_make_sp<SkPDFSharedStream>(std::move(fontAsset)); |
| fontStream->dict()->insertInt("Length1", fontSize); |
| descriptor->insertObjRef("FontFile2", std::move(fontStream)); |
| break; |
| } |
| case SkAdvancedTypefaceMetrics::kType1CID_Font: { |
| auto fontStream = sk_make_sp<SkPDFSharedStream>(std::move(fontAsset)); |
| fontStream->dict()->insertName("Subtype", "CIDFontType0C"); |
| descriptor->insertObjRef("FontFile3", std::move(fontStream)); |
| break; |
| } |
| default: |
| SkASSERT(false); |
| } |
| } |
| |
| auto newCIDFont = sk_make_sp<SkPDFDict>("Font"); |
| newCIDFont->insertObjRef("FontDescriptor", std::move(descriptor)); |
| newCIDFont->insertName("BaseFont", metrics.fFontName); |
| |
| switch (type) { |
| case SkAdvancedTypefaceMetrics::kType1CID_Font: |
| newCIDFont->insertName("Subtype", "CIDFontType0"); |
| break; |
| case SkAdvancedTypefaceMetrics::kTrueType_Font: |
| newCIDFont->insertName("Subtype", "CIDFontType2"); |
| newCIDFont->insertName("CIDToGIDMap", "Identity"); |
| break; |
| default: |
| SkASSERT(false); |
| } |
| auto sysInfo = sk_make_sp<SkPDFDict>(); |
| sysInfo->insertString("Registry", "Adobe"); |
| sysInfo->insertString("Ordering", "Identity"); |
| sysInfo->insertInt("Supplement", 0); |
| newCIDFont->insertObject("CIDSystemInfo", std::move(sysInfo)); |
| |
| int16_t defaultWidth = 0; |
| { |
| int emSize; |
| SkAutoGlyphCache glyphCache = SkPDFFont::MakeVectorCache(face, &emSize); |
| sk_sp<SkPDFArray> widths = SkPDFMakeCIDGlyphWidthsArray( |
| glyphCache.get(), &this->glyphUsage(), SkToS16(emSize), &defaultWidth); |
| if (widths && widths->size() > 0) { |
| newCIDFont->insertObject("W", std::move(widths)); |
| } |
| newCIDFont->insertScalar( |
| "DW", scaleFromFontUnits(defaultWidth, SkToS16(emSize))); |
| } |
| |
| //////////////////////////////////////////////////////////////////////////// |
| |
| this->insertName("Subtype", "Type0"); |
| this->insertName("BaseFont", metrics.fFontName); |
| this->insertName("Encoding", "Identity-H"); |
| auto descendantFonts = sk_make_sp<SkPDFArray>(); |
| descendantFonts->appendObjRef(std::move(newCIDFont)); |
| this->insertObject("DescendantFonts", std::move(descendantFonts)); |
| |
| if (metrics.fGlyphToUnicode.count() > 0) { |
| this->insertObjRef("ToUnicode", |
| SkPDFMakeToUnicodeCmap(metrics.fGlyphToUnicode, |
| &this->glyphUsage(), |
| multiByteGlyphs(), |
| firstGlyphID(), |
| lastGlyphID())); |
| } |
| SkDEBUGCODE(fPopulated = true); |
| return; |
| } |
| |
| /////////////////////////////////////////////////////////////////////////////// |
| // class SkPDFType1Font |
| /////////////////////////////////////////////////////////////////////////////// |
| |
| static sk_sp<SkPDFDict> make_type1_font_descriptor( |
| SkTypeface* typeface, |
| const SkAdvancedTypefaceMetrics& info) { |
| auto descriptor = sk_make_sp<SkPDFDict>("FontDescriptor"); |
| uint16_t emSize = SkToU16(typeface->getUnitsPerEm()); |
| add_common_font_descriptor_entries(descriptor.get(), info, emSize, 0); |
| if (!can_embed(info)) { |
| return descriptor; |
| } |
| int ttcIndex; |
| size_t header SK_INIT_TO_AVOID_WARNING; |
| size_t data SK_INIT_TO_AVOID_WARNING; |
| size_t trailer SK_INIT_TO_AVOID_WARNING; |
| std::unique_ptr<SkStreamAsset> rawFontData(typeface->openStream(&ttcIndex)); |
| sk_sp<SkData> fontData = SkPDFConvertType1FontStream(std::move(rawFontData), |
| &header, &data, &trailer); |
| if (fontData) { |
| auto fontStream = sk_make_sp<SkPDFStream>(std::move(fontData)); |
| fontStream->dict()->insertInt("Length1", header); |
| fontStream->dict()->insertInt("Length2", data); |
| fontStream->dict()->insertInt("Length3", trailer); |
| descriptor->insertObjRef("FontFile", std::move(fontStream)); |
| } |
| return descriptor; |
| } |
| |
| static void populate_type_1_font(SkPDFDict* font, |
| const SkAdvancedTypefaceMetrics& info, |
| SkTypeface* typeface, |
| SkGlyphID firstGlyphID, |
| SkGlyphID lastGlyphID) { |
| font->insertName("Subtype", "Type1"); |
| font->insertName("BaseFont", info.fFontName); |
| |
| // glyphCount not including glyph 0 |
| unsigned glyphCount = 1 + lastGlyphID - firstGlyphID; |
| SkASSERT(glyphCount > 0 && glyphCount <= 255); |
| font->insertInt("FirstChar", (size_t)0); |
| font->insertInt("LastChar", (size_t)glyphCount); |
| { |
| int emSize; |
| SkAutoGlyphCache glyphCache = SkPDFFont::MakeVectorCache(typeface, &emSize); |
| auto widths = sk_make_sp<SkPDFArray>(); |
| SkScalar advance = glyphCache->getGlyphIDAdvance(0).fAdvanceX; |
| widths->appendScalar(from_font_units(advance, SkToU16(emSize))); |
| for (unsigned gID = firstGlyphID; gID <= lastGlyphID; gID++) { |
| advance = glyphCache->getGlyphIDAdvance(gID).fAdvanceX; |
| widths->appendScalar(from_font_units(advance, SkToU16(emSize))); |
| } |
| font->insertObject("Widths", std::move(widths)); |
| } |
| auto encDiffs = sk_make_sp<SkPDFArray>(); |
| encDiffs->reserve(lastGlyphID - firstGlyphID + 3); |
| encDiffs->appendInt(0); |
| const SkTArray<SkString>& glyphNames = info.fGlyphNames; |
| SkASSERT(glyphNames.count() > lastGlyphID); |
| encDiffs->appendName(glyphNames[0].c_str()); |
| const SkString unknown("UNKNOWN"); |
| for (int gID = firstGlyphID; gID <= lastGlyphID; gID++) { |
| const bool valid = gID < glyphNames.count() && !glyphNames[gID].isEmpty(); |
| const SkString& name = valid ? glyphNames[gID] : unknown; |
| encDiffs->appendName(name); |
| } |
| |
| auto encoding = sk_make_sp<SkPDFDict>("Encoding"); |
| encoding->insertObject("Differences", std::move(encDiffs)); |
| font->insertObject("Encoding", std::move(encoding)); |
| } |
| |
| SkPDFType1Font::SkPDFType1Font(SkPDFFont::Info info, |
| const SkAdvancedTypefaceMetrics& metrics, |
| SkPDFCanon* canon) |
| : SkPDFFont(std::move(info)) |
| { |
| SkFontID fontID = this->typeface()->uniqueID(); |
| sk_sp<SkPDFDict> fontDescriptor; |
| if (sk_sp<SkPDFDict>* ptr = canon->fFontDescriptors.find(fontID)) { |
| fontDescriptor = *ptr; |
| } else { |
| fontDescriptor = make_type1_font_descriptor(this->typeface(), metrics); |
| canon->fFontDescriptors.set(fontID, fontDescriptor); |
| } |
| this->insertObjRef("FontDescriptor", std::move(fontDescriptor)); |
| // TODO(halcanary): subset this (advances and names). |
| populate_type_1_font(this, metrics, this->typeface(), |
| this->firstGlyphID(), this->lastGlyphID()); |
| } |
| |
| /////////////////////////////////////////////////////////////////////////////// |
| // class SkPDFType3Font |
| /////////////////////////////////////////////////////////////////////////////// |
| |
| namespace { |
| // returns [0, first, first+1, ... last-1, last] |
| struct SingleByteGlyphIdIterator { |
| SingleByteGlyphIdIterator(SkGlyphID first, SkGlyphID last) |
| : fFirst(first), fLast(last) { |
| SkASSERT(fFirst > 0); |
| SkASSERT(fLast >= first); |
| } |
| struct Iter { |
| void operator++() { |
| fCurrent = (0 == fCurrent) ? fFirst : fCurrent + 1; |
| } |
| // This is an input_iterator |
| SkGlyphID operator*() const { return (SkGlyphID)fCurrent; } |
| bool operator!=(const Iter& rhs) const { |
| return fCurrent != rhs.fCurrent; |
| } |
| Iter(SkGlyphID f, int c) : fFirst(f), fCurrent(c) {} |
| private: |
| const SkGlyphID fFirst; |
| int fCurrent; // must be int to make fLast+1 to fit |
| }; |
| Iter begin() const { return Iter(fFirst, 0); } |
| Iter end() const { return Iter(fFirst, (int)fLast + 1); } |
| private: |
| const SkGlyphID fFirst; |
| const SkGlyphID fLast; |
| }; |
| } |
| |
| static void add_type3_font_info(SkPDFCanon* canon, |
| SkPDFDict* font, |
| SkTypeface* typeface, |
| const SkBitSet& subset, |
| SkGlyphID firstGlyphID, |
| SkGlyphID lastGlyphID) { |
| const SkAdvancedTypefaceMetrics* metrics = SkPDFFont::GetMetrics(typeface, canon); |
| SkASSERT(lastGlyphID >= firstGlyphID); |
| // Remove unused glyphs at the end of the range. |
| // Keep the lastGlyphID >= firstGlyphID invariant true. |
| while (lastGlyphID > firstGlyphID && !subset.has(lastGlyphID)) { |
| --lastGlyphID; |
| } |
| int unitsPerEm; |
| SkAutoGlyphCache cache = SkPDFFont::MakeVectorCache(typeface, &unitsPerEm); |
| SkScalar emSize = (SkScalar)unitsPerEm; |
| font->insertName("Subtype", "Type3"); |
| // Flip about the x-axis and scale by 1/emSize. |
| SkMatrix fontMatrix; |
| fontMatrix.setScale(SkScalarInvert(emSize), -SkScalarInvert(emSize)); |
| font->insertObject("FontMatrix", SkPDFUtils::MatrixToArray(fontMatrix)); |
| |
| auto charProcs = sk_make_sp<SkPDFDict>(); |
| auto encoding = sk_make_sp<SkPDFDict>("Encoding"); |
| |
| auto encDiffs = sk_make_sp<SkPDFArray>(); |
| // length(firstGlyphID .. lastGlyphID) == lastGlyphID - firstGlyphID + 1 |
| // plus 1 for glyph 0; |
| SkASSERT(firstGlyphID > 0); |
| SkASSERT(lastGlyphID >= firstGlyphID); |
| int glyphCount = lastGlyphID - firstGlyphID + 2; |
| // one other entry for the index of first glyph. |
| encDiffs->reserve(glyphCount + 1); |
| encDiffs->appendInt(0); // index of first glyph |
| |
| auto widthArray = sk_make_sp<SkPDFArray>(); |
| widthArray->reserve(glyphCount); |
| |
| SkIRect bbox = SkIRect::MakeEmpty(); |
| |
| sk_sp<SkPDFStream> emptyStream; |
| for (SkGlyphID gID : SingleByteGlyphIdIterator(firstGlyphID, lastGlyphID)) { |
| bool skipGlyph = gID != 0 && !subset.has(gID); |
| SkString characterName; |
| SkScalar advance = 0.0f; |
| SkIRect glyphBBox; |
| if (skipGlyph) { |
| characterName.set("g0"); |
| } else { |
| characterName.printf("g%X", gID); |
| const SkGlyph& glyph = cache->getGlyphIDMetrics(gID); |
| advance = SkFloatToScalar(glyph.fAdvanceX); |
| glyphBBox = SkIRect::MakeXYWH(glyph.fLeft, glyph.fTop, |
| glyph.fWidth, glyph.fHeight); |
| bbox.join(glyphBBox); |
| const SkPath* path = cache->findPath(glyph); |
| if (path && !path->isEmpty()) { |
| SkDynamicMemoryWStream content; |
| setGlyphWidthAndBoundingBox(SkFloatToScalar(glyph.fAdvanceX), glyphBBox, |
| &content); |
| SkPDFUtils::EmitPath(*path, SkPaint::kFill_Style, &content); |
| SkPDFUtils::PaintPath(SkPaint::kFill_Style, path->getFillType(), |
| &content); |
| charProcs->insertObjRef( |
| characterName, sk_make_sp<SkPDFStream>( |
| std::unique_ptr<SkStreamAsset>(content.detachAsStream()))); |
| } else { |
| if (!emptyStream) { |
| emptyStream = sk_make_sp<SkPDFStream>( |
| std::unique_ptr<SkStreamAsset>( |
| new SkMemoryStream((size_t)0))); |
| } |
| charProcs->insertObjRef(characterName, emptyStream); |
| } |
| } |
| encDiffs->appendName(characterName.c_str()); |
| widthArray->appendScalar(advance); |
| } |
| |
| encoding->insertObject("Differences", std::move(encDiffs)); |
| font->insertInt("FirstChar", 0); |
| font->insertInt("LastChar", lastGlyphID - firstGlyphID + 1); |
| /* FontBBox: "A rectangle expressed in the glyph coordinate |
| system, specifying the font bounding box. This is the smallest |
| rectangle enclosing the shape that would result if all of the |
| glyphs of the font were placed with their origins coincident and |
| then filled." */ |
| auto fontBBox = sk_make_sp<SkPDFArray>(); |
| fontBBox->reserve(4); |
| fontBBox->appendInt(bbox.left()); |
| fontBBox->appendInt(bbox.bottom()); |
| fontBBox->appendInt(bbox.right()); |
| fontBBox->appendInt(bbox.top()); |
| font->insertObject("FontBBox", std::move(fontBBox)); |
| font->insertName("CIDToGIDMap", "Identity"); |
| if (metrics && metrics->fGlyphToUnicode.count() > 0) { |
| font->insertObjRef("ToUnicode", |
| SkPDFMakeToUnicodeCmap(metrics->fGlyphToUnicode, |
| &subset, |
| false, |
| firstGlyphID, |
| lastGlyphID)); |
| } |
| auto descriptor = sk_make_sp<SkPDFDict>("FontDescriptor"); |
| int32_t fontDescriptorFlags = kPdfSymbolic; |
| if (metrics) { |
| // Type3 FontDescriptor does not require all the same fields. |
| descriptor->insertName("FontName", metrics->fFontName); |
| descriptor->insertInt("ItalicAngle", metrics->fItalicAngle); |
| fontDescriptorFlags |= (int32_t)metrics->fStyle; |
| } |
| descriptor->insertInt("Flags", fontDescriptorFlags); |
| font->insertObjRef("FontDescriptor", std::move(descriptor)); |
| font->insertObject("Widths", std::move(widthArray)); |
| font->insertObject("Encoding", std::move(encoding)); |
| font->insertObject("CharProcs", std::move(charProcs)); |
| } |
| |
| SkPDFType3Font::SkPDFType3Font(SkPDFFont::Info info, |
| const SkAdvancedTypefaceMetrics& metrics) |
| : SkPDFFont(std::move(info)) {} |
| |
| void SkPDFType3Font::getFontSubset(SkPDFCanon* canon) { |
| add_type3_font_info(canon, this, this->typeface(), this->glyphUsage(), |
| this->firstGlyphID(), this->lastGlyphID()); |
| } |
| |
| //////////////////////////////////////////////////////////////////////////////// |
| |
| bool SkPDFFont::CanEmbedTypeface(SkTypeface* typeface, SkPDFCanon* canon) { |
| const SkAdvancedTypefaceMetrics* metrics = SkPDFFont::GetMetrics(typeface, canon); |
| return metrics && can_embed(*metrics); |
| } |
| |
| void SkPDFFont::drop() { |
| fTypeface = nullptr; |
| fGlyphUsage.~SkBitSet(); |
| new (&fGlyphUsage) SkBitSet(0); |
| this->SkPDFDict::drop(); |
| } |
