C++ SkTScopedComPtr::GetLoader方法代码示例

SkStreamAsset* DWriteFontTypeface::onOpenStream(int* ttcIndex) const {
    *ttcIndex = fDWriteFontFace->GetIndex();

    UINT32 numFiles;
    HRNM(fDWriteFontFace->GetFiles(&numFiles, nullptr),
         "Could not get number of font files.");
    if (numFiles != 1) {
        return nullptr;
    }

    SkTScopedComPtr<IDWriteFontFile> fontFile;
    HRNM(fDWriteFontFace->GetFiles(&numFiles, &fontFile), "Could not get font files.");

    const void* fontFileKey;
    UINT32 fontFileKeySize;
    HRNM(fontFile->GetReferenceKey(&fontFileKey, &fontFileKeySize),
         "Could not get font file reference key.");

    SkTScopedComPtr<IDWriteFontFileLoader> fontFileLoader;
    HRNM(fontFile->GetLoader(&fontFileLoader), "Could not get font file loader.");

    SkTScopedComPtr<IDWriteFontFileStream> fontFileStream;
    HRNM(fontFileLoader->CreateStreamFromKey(fontFileKey, fontFileKeySize,
                                             &fontFileStream),
         "Could not create font file stream.");

    return new SkDWriteFontFileStream(fontFileStream.get());
}

static bool FindByDWriteFont(SkTypeface* cached, void* ctx) {
    DWriteFontTypeface* cshFace = reinterpret_cast<DWriteFontTypeface*>(cached);
    ProtoDWriteTypeface* ctxFace = reinterpret_cast<ProtoDWriteTypeface*>(ctx);
    bool same;

    //Check to see if the two fonts are identical.
    HRB(are_same(cshFace->fDWriteFont.get(), ctxFace->fDWriteFont, same));
    if (same) {
        return true;
    }

    HRB(are_same(cshFace->fDWriteFontFace.get(), ctxFace->fDWriteFontFace, same));
    if (same) {
        return true;
    }

    //Check if the two fonts share the same loader and have the same key.
    UINT32 cshNumFiles;
    UINT32 ctxNumFiles;
    HRB(cshFace->fDWriteFontFace->GetFiles(&cshNumFiles, nullptr));
    HRB(ctxFace->fDWriteFontFace->GetFiles(&ctxNumFiles, nullptr));
    if (cshNumFiles != ctxNumFiles) {
        return false;
    }

    SkTScopedComPtr<IDWriteFontFile> cshFontFile;
    SkTScopedComPtr<IDWriteFontFile> ctxFontFile;
    HRB(cshFace->fDWriteFontFace->GetFiles(&cshNumFiles, &cshFontFile));
    HRB(ctxFace->fDWriteFontFace->GetFiles(&ctxNumFiles, &ctxFontFile));

    //for (each file) { //we currently only admit fonts from one file.
    SkTScopedComPtr<IDWriteFontFileLoader> cshFontFileLoader;
    SkTScopedComPtr<IDWriteFontFileLoader> ctxFontFileLoader;
    HRB(cshFontFile->GetLoader(&cshFontFileLoader));
    HRB(ctxFontFile->GetLoader(&ctxFontFileLoader));
    HRB(are_same(cshFontFileLoader.get(), ctxFontFileLoader.get(), same));
    if (!same) {
        return false;
    }
    //}

    const void* cshRefKey;
    UINT32 cshRefKeySize;
    const void* ctxRefKey;
    UINT32 ctxRefKeySize;
    HRB(cshFontFile->GetReferenceKey(&cshRefKey, &cshRefKeySize));
    HRB(ctxFontFile->GetReferenceKey(&ctxRefKey, &ctxRefKeySize));
    if (cshRefKeySize != ctxRefKeySize) {
        return false;
    }
    if (0 != memcmp(cshRefKey, ctxRefKey, ctxRefKeySize)) {
        return false;
    }

    //TODO: better means than comparing name strings?
    //NOTE: .ttc and fake bold/italic will end up here.
    SkTScopedComPtr<IDWriteLocalizedStrings> cshFamilyNames;
    SkTScopedComPtr<IDWriteLocalizedStrings> cshFaceNames;
    HRB(cshFace->fDWriteFontFamily->GetFamilyNames(&cshFamilyNames));
    HRB(cshFace->fDWriteFont->GetFaceNames(&cshFaceNames));
    UINT32 cshFamilyNameLength;
    UINT32 cshFaceNameLength;
    HRB(cshFamilyNames->GetStringLength(0, &cshFamilyNameLength));
    HRB(cshFaceNames->GetStringLength(0, &cshFaceNameLength));

    SkTScopedComPtr<IDWriteLocalizedStrings> ctxFamilyNames;
    SkTScopedComPtr<IDWriteLocalizedStrings> ctxFaceNames;
    HRB(ctxFace->fDWriteFontFamily->GetFamilyNames(&ctxFamilyNames));
    HRB(ctxFace->fDWriteFont->GetFaceNames(&ctxFaceNames));
    UINT32 ctxFamilyNameLength;
    UINT32 ctxFaceNameLength;
    HRB(ctxFamilyNames->GetStringLength(0, &ctxFamilyNameLength));
    HRB(ctxFaceNames->GetStringLength(0, &ctxFaceNameLength));

    if (cshFamilyNameLength != ctxFamilyNameLength ||
        cshFaceNameLength != ctxFaceNameLength)
    {
        return false;
    }

    SkSMallocWCHAR cshFamilyName(cshFamilyNameLength+1);
    SkSMallocWCHAR cshFaceName(cshFaceNameLength+1);
    HRB(cshFamilyNames->GetString(0, cshFamilyName.get(), cshFamilyNameLength+1));
    HRB(cshFaceNames->GetString(0, cshFaceName.get(), cshFaceNameLength+1));

    SkSMallocWCHAR ctxFamilyName(ctxFamilyNameLength+1);
    SkSMallocWCHAR ctxFaceName(ctxFaceNameLength+1);
    HRB(ctxFamilyNames->GetString(0, ctxFamilyName.get(), ctxFamilyNameLength+1));
    HRB(ctxFaceNames->GetString(0, ctxFaceName.get(), ctxFaceNameLength+1));

    return wcscmp(cshFamilyName.get(), ctxFamilyName.get()) == 0 &&
           wcscmp(cshFaceName.get(), ctxFaceName.get()) == 0;
}