The Tor Browser: gfx/thebes/gfxDWriteFonts.cpp@97036ab72558 (annotated)

gfx/thebes/gfxDWriteFonts.cpp@97036ab72558 (annotated)

gfx/thebes/gfxDWriteFonts.cpp

Tue, 06 Jan 2015 21:39:09 +0100

author: Michael Schloh von Bennewitz <michael@schloh.com>
date: Tue, 06 Jan 2015 21:39:09 +0100
branch: TOR_BUG_9701
changeset 8: 97036ab72558
permissions: -rw-r--r--

Conditionally force memory storage according to privacy.thirdparty.isolate;
This solves Tor bug #9701, complying with disk avoidance documented in
https://www.torproject.org/projects/torbrowser/design/#disk-avoidance.

 /* -*- Mode: C++; tab-width: 20; indent-tabs-mode: nil; c-basic-offset: 4 -*-
  * This Source Code Form is subject to the terms of the Mozilla Public
  * License, v. 2.0. If a copy of the MPL was not distributed with this
  * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
 #include "gfxDWriteFonts.h"
 #include "mozilla/MemoryReporting.h"
 #include "gfxDWriteShaper.h"
 #include "gfxHarfBuzzShaper.h"
 #include <algorithm>
 #include "gfxGraphiteShaper.h"
 #include "gfxDWriteFontList.h"
 #include "gfxContext.h"
 #include <dwrite.h>
 #include "gfxDWriteTextAnalysis.h"
 #include "harfbuzz/hb.h"
 // Chosen this as to resemble DWrite's own oblique face style.
 #define OBLIQUE_SKEW_FACTOR 0.3
 using namespace mozilla;
 using namespace mozilla::gfx;
 // This is also in gfxGDIFont.cpp. Would be nice to put it somewhere common,
 // but we can't declare it in the gfxFont.h or gfxFontUtils.h headers
 // because those are exported, and the cairo headers aren't.
 static inline cairo_antialias_t
 GetCairoAntialiasOption(gfxFont::AntialiasOption anAntialiasOption)
 {
     switch (anAntialiasOption) {
     default:
     case gfxFont::kAntialiasDefault:
         return CAIRO_ANTIALIAS_DEFAULT;
     case gfxFont::kAntialiasNone:
         return CAIRO_ANTIALIAS_NONE;
     case gfxFont::kAntialiasGrayscale:
         return CAIRO_ANTIALIAS_GRAY;
     case gfxFont::kAntialiasSubpixel:
         return CAIRO_ANTIALIAS_SUBPIXEL;
     }
 }
 // Code to determine whether Windows is set to use ClearType font smoothing;
 // based on private functions in cairo-win32-font.c
 #ifndef SPI_GETFONTSMOOTHINGTYPE
 #define SPI_GETFONTSMOOTHINGTYPE 0x200a
 #endif
 #ifndef FE_FONTSMOOTHINGCLEARTYPE
 #define FE_FONTSMOOTHINGCLEARTYPE 2
 #endif
 static bool
 UsingClearType()
 {
     BOOL fontSmoothing;
     if (!SystemParametersInfo(SPI_GETFONTSMOOTHING, 0, &fontSmoothing, 0) ||
         !fontSmoothing)
     {
         return false;
     }
     UINT type;
     if (SystemParametersInfo(SPI_GETFONTSMOOTHINGTYPE, 0, &type, 0) &&
         type == FE_FONTSMOOTHINGCLEARTYPE)
     {
         return true;
     }
     return false;
 }
 ////////////////////////////////////////////////////////////////////////////////
 // gfxDWriteFont
 gfxDWriteFont::gfxDWriteFont(gfxFontEntry *aFontEntry,
                              const gfxFontStyle *aFontStyle,
                              bool aNeedsBold,
                              AntialiasOption anAAOption)
     : gfxFont(aFontEntry, aFontStyle, anAAOption)
     , mCairoFontFace(nullptr)
     , mMetrics(nullptr)
     , mNeedsOblique(false)
     , mNeedsBold(aNeedsBold)
     , mUseSubpixelPositions(false)
     , mAllowManualShowGlyphs(true)
 {
     gfxDWriteFontEntry *fe =
         static_cast<gfxDWriteFontEntry*>(aFontEntry);
     nsresult rv;
     DWRITE_FONT_SIMULATIONS sims = DWRITE_FONT_SIMULATIONS_NONE;
     if ((GetStyle()->style & (NS_FONT_STYLE_ITALIC | NS_FONT_STYLE_OBLIQUE)) &&
         !fe->IsItalic()) {
             // For this we always use the font_matrix for uniformity. Not the
             // DWrite simulation.
             mNeedsOblique = true;
     }
     if (aNeedsBold) {
         sims |= DWRITE_FONT_SIMULATIONS_BOLD;
     }
     rv = fe->CreateFontFace(getter_AddRefs(mFontFace), sims);
     if (NS_FAILED(rv)) {
         mIsValid = false;
         return;
     }
     ComputeMetrics(anAAOption);
     if (FontCanSupportGraphite()) {
         mGraphiteShaper = new gfxGraphiteShaper(this);
     }
     if (FontCanSupportHarfBuzz()) {
         mHarfBuzzShaper = new gfxHarfBuzzShaper(this);
     }
 }
 gfxDWriteFont::~gfxDWriteFont()
 {
     if (mCairoFontFace) {
         cairo_font_face_destroy(mCairoFontFace);
     }
     if (mScaledFont) {
         cairo_scaled_font_destroy(mScaledFont);
     }
     delete mMetrics;
 }
 gfxFont*
 gfxDWriteFont::CopyWithAntialiasOption(AntialiasOption anAAOption)
 {
     return new gfxDWriteFont(static_cast<gfxDWriteFontEntry*>(mFontEntry.get()),
                              &mStyle, mNeedsBold, anAAOption);
 }
 void
 gfxDWriteFont::CreatePlatformShaper()
 {
     mPlatformShaper = new gfxDWriteShaper(this);
 }
 const gfxFont::Metrics&
 gfxDWriteFont::GetMetrics()
 {
     return *mMetrics;
 }
 bool
 gfxDWriteFont::GetFakeMetricsForArialBlack(DWRITE_FONT_METRICS *aFontMetrics)
 {
     gfxFontStyle style(mStyle);
     style.weight = 700;
     bool needsBold;
     gfxFontEntry* fe =
         gfxPlatformFontList::PlatformFontList()->
             FindFontForFamily(NS_LITERAL_STRING("Arial"), &style, needsBold);
     if (!fe || fe == mFontEntry) {
         return false;
     }
     nsRefPtr<gfxFont> font = fe->FindOrMakeFont(&style, needsBold);
     gfxDWriteFont *dwFont = static_cast<gfxDWriteFont*>(font.get());
     dwFont->mFontFace->GetMetrics(aFontMetrics);
     return true;
 }
 void
 gfxDWriteFont::ComputeMetrics(AntialiasOption anAAOption)
 {
     DWRITE_FONT_METRICS fontMetrics;
     if (!(mFontEntry->Weight() == 900 &&
           !mFontEntry->IsUserFont() &&
           mFontEntry->Name().EqualsLiteral("Arial Black") &&
           GetFakeMetricsForArialBlack(&fontMetrics)))
     {
         mFontFace->GetMetrics(&fontMetrics);
     }
     if (mStyle.sizeAdjust != 0.0) {
         gfxFloat aspect = (gfxFloat)fontMetrics.xHeight /
                    fontMetrics.designUnitsPerEm;
         mAdjustedSize = mStyle.GetAdjustedSize(aspect);
     } else {
         mAdjustedSize = mStyle.size;
     }
     // Note that GetMeasuringMode depends on mAdjustedSize
     if ((anAAOption == gfxFont::kAntialiasDefault &&
          UsingClearType() &&
          GetMeasuringMode() == DWRITE_MEASURING_MODE_NATURAL) ||
         anAAOption == gfxFont::kAntialiasSubpixel)
     {
         mUseSubpixelPositions = true;
         // note that this may be reset to FALSE if we determine that a bitmap
         // strike is going to be used
     }
     gfxDWriteFontEntry *fe =
         static_cast<gfxDWriteFontEntry*>(mFontEntry.get());
     if (fe->IsCJKFont() && HasBitmapStrikeForSize(NS_lround(mAdjustedSize))) {
         mAdjustedSize = NS_lround(mAdjustedSize);
         mUseSubpixelPositions = false;
         // if we have bitmaps, we need to tell Cairo NOT to use subpixel AA,
         // to avoid the manual-subpixel codepath in cairo-d2d-surface.cpp
         // which fails to render bitmap glyphs (see bug 626299).
         // This option will be passed to the cairo_dwrite_scaled_font_t
         // after creation.
         mAllowManualShowGlyphs = false;
     }
     mMetrics = new gfxFont::Metrics;
     ::memset(mMetrics, 0, sizeof(*mMetrics));
     mFUnitsConvFactor = float(mAdjustedSize / fontMetrics.designUnitsPerEm);
     mMetrics->xHeight = fontMetrics.xHeight * mFUnitsConvFactor;
     mMetrics->maxAscent = ceil(fontMetrics.ascent * mFUnitsConvFactor);
     mMetrics->maxDescent = ceil(fontMetrics.descent * mFUnitsConvFactor);
     mMetrics->maxHeight = mMetrics->maxAscent + mMetrics->maxDescent;
     mMetrics->emHeight = mAdjustedSize;
     mMetrics->emAscent = mMetrics->emHeight *
         mMetrics->maxAscent / mMetrics->maxHeight;
     mMetrics->emDescent = mMetrics->emHeight - mMetrics->emAscent;
     mMetrics->maxAdvance = mAdjustedSize;
     // try to get the true maxAdvance value from 'hhea'
     gfxFontEntry::AutoTable hheaTable(GetFontEntry(),
                                       TRUETYPE_TAG('h','h','e','a'));
     if (hheaTable) {
         uint32_t len;
         const HheaTable* hhea =
             reinterpret_cast<const HheaTable*>(hb_blob_get_data(hheaTable, &len));
         if (len >= sizeof(HheaTable)) {
             mMetrics->maxAdvance =
                 uint16_t(hhea->advanceWidthMax) * mFUnitsConvFactor;
         }
     }
     mMetrics->internalLeading = std::max(mMetrics->maxHeight - mMetrics->emHeight, 0.0);
     mMetrics->externalLeading = ceil(fontMetrics.lineGap * mFUnitsConvFactor);
     UINT16 glyph = (uint16_t)GetSpaceGlyph();
     mMetrics->spaceWidth = MeasureGlyphWidth(glyph);
     // try to get aveCharWidth from the OS/2 table, fall back to measuring 'x'
     // if the table is not available or if using hinted/pixel-snapped widths
     if (mUseSubpixelPositions) {
         mMetrics->aveCharWidth = 0;
         gfxFontEntry::AutoTable os2Table(GetFontEntry(),
                                          TRUETYPE_TAG('O','S','/','2'));
         if (os2Table) {
             uint32_t len;
             const OS2Table* os2 =
                 reinterpret_cast<const OS2Table*>(hb_blob_get_data(os2Table, &len));
             if (len >= 4) {
                 // Not checking against sizeof(mozilla::OS2Table) here because older
                 // versions of the table have different sizes; we only need the first
                 // two 16-bit fields here.
                 mMetrics->aveCharWidth =
                     int16_t(os2->xAvgCharWidth) * mFUnitsConvFactor;
             }
         }
     }
     UINT32 ucs;
     if (mMetrics->aveCharWidth < 1) {
         ucs = L'x';
         if (SUCCEEDED(mFontFace->GetGlyphIndicesA(&ucs, 1, &glyph))) {
             mMetrics->aveCharWidth = MeasureGlyphWidth(glyph);
         }
         if (mMetrics->aveCharWidth < 1) {
             // Let's just assume the X is square.
             mMetrics->aveCharWidth = fontMetrics.xHeight * mFUnitsConvFactor;
         }
     }
     ucs = L'0';
     if (SUCCEEDED(mFontFace->GetGlyphIndicesA(&ucs, 1, &glyph))) {
         mMetrics->zeroOrAveCharWidth = MeasureGlyphWidth(glyph);
     }
     if (mMetrics->zeroOrAveCharWidth < 1) {
         mMetrics->zeroOrAveCharWidth = mMetrics->aveCharWidth;
     }
     mMetrics->underlineOffset =
         fontMetrics.underlinePosition * mFUnitsConvFactor;
     mMetrics->underlineSize =
         fontMetrics.underlineThickness * mFUnitsConvFactor;
     mMetrics->strikeoutOffset =
         fontMetrics.strikethroughPosition * mFUnitsConvFactor;
     mMetrics->strikeoutSize =
         fontMetrics.strikethroughThickness * mFUnitsConvFactor;
     mMetrics->superscriptOffset = 0;
     mMetrics->subscriptOffset = 0;
     SanitizeMetrics(mMetrics, GetFontEntry()->mIsBadUnderlineFont);
 #if 0
     printf("Font: %p (%s) size: %f\n", this,
            NS_ConvertUTF16toUTF8(GetName()).get(), mStyle.size);
     printf("    emHeight: %f emAscent: %f emDescent: %f\n", mMetrics->emHeight, mMetrics->emAscent, mMetrics->emDescent);
     printf("    maxAscent: %f maxDescent: %f maxAdvance: %f\n", mMetrics->maxAscent, mMetrics->maxDescent, mMetrics->maxAdvance);
     printf("    internalLeading: %f externalLeading: %f\n", mMetrics->internalLeading, mMetrics->externalLeading);
     printf("    spaceWidth: %f aveCharWidth: %f zeroOrAve: %f xHeight: %f\n",
            mMetrics->spaceWidth, mMetrics->aveCharWidth, mMetrics->zeroOrAveCharWidth, mMetrics->xHeight);
     printf("    uOff: %f uSize: %f stOff: %f stSize: %f supOff: %f subOff: %f\n",
            mMetrics->underlineOffset, mMetrics->underlineSize, mMetrics->strikeoutOffset, mMetrics->strikeoutSize,
            mMetrics->superscriptOffset, mMetrics->subscriptOffset);
 #endif
 }
 using namespace mozilla; // for AutoSwap_* types
 struct EBLCHeader {
     AutoSwap_PRUint32 version;
     AutoSwap_PRUint32 numSizes;
 };
 struct SbitLineMetrics {
     int8_t  ascender;
     int8_t  descender;
     uint8_t widthMax;
     int8_t  caretSlopeNumerator;
     int8_t  caretSlopeDenominator;
     int8_t  caretOffset;
     int8_t  minOriginSB;
     int8_t  minAdvanceSB;
     int8_t  maxBeforeBL;
     int8_t  minAfterBL;
     int8_t  pad1;
     int8_t  pad2;
 };
 struct BitmapSizeTable {
     AutoSwap_PRUint32 indexSubTableArrayOffset;
     AutoSwap_PRUint32 indexTablesSize;
     AutoSwap_PRUint32 numberOfIndexSubTables;
     AutoSwap_PRUint32 colorRef;
     SbitLineMetrics   hori;
     SbitLineMetrics   vert;
     AutoSwap_PRUint16 startGlyphIndex;
     AutoSwap_PRUint16 endGlyphIndex;
     uint8_t           ppemX;
     uint8_t           ppemY;
     uint8_t           bitDepth;
     uint8_t           flags;
 };
 typedef EBLCHeader EBSCHeader;
 struct BitmapScaleTable {
     SbitLineMetrics   hori;
     SbitLineMetrics   vert;
     uint8_t           ppemX;
     uint8_t           ppemY;
     uint8_t           substitutePpemX;
     uint8_t           substitutePpemY;
 };
 bool
 gfxDWriteFont::HasBitmapStrikeForSize(uint32_t aSize)
 {
     uint8_t *tableData;
     uint32_t len;
     void *tableContext;
     BOOL exists;
     HRESULT hr =
         mFontFace->TryGetFontTable(DWRITE_MAKE_OPENTYPE_TAG('E', 'B', 'L', 'C'),
                                    (const void**)&tableData, &len,
                                    &tableContext, &exists);
     if (FAILED(hr)) {
         return false;
     }
     bool hasStrike = false;
     // not really a loop, but this lets us use 'break' to skip out of the block
     // as soon as we know the answer, and skips it altogether if the table is
     // not present
     while (exists) {
         if (len < sizeof(EBLCHeader)) {
             break;
         }
         const EBLCHeader *hdr = reinterpret_cast<const EBLCHeader*>(tableData);
         if (hdr->version != 0x00020000) {
             break;
         }
         uint32_t numSizes = hdr->numSizes;
         if (numSizes > 0xffff) { // sanity-check, prevent overflow below
             break;
         }
         if (len < sizeof(EBLCHeader) + numSizes * sizeof(BitmapSizeTable)) {
             break;
         }
         const BitmapSizeTable *sizeTable =
             reinterpret_cast<const BitmapSizeTable*>(hdr + 1);
         for (uint32_t i = 0; i < numSizes; ++i, ++sizeTable) {
             if (sizeTable->ppemX == aSize && sizeTable->ppemY == aSize) {
                 // we ignore a strike that contains fewer than 4 glyphs,
                 // as that probably indicates a font such as Courier New
                 // that provides bitmaps ONLY for the "shading" characters
                 // U+2591..2593
                 hasStrike = (uint16_t(sizeTable->endGlyphIndex) >=
                              uint16_t(sizeTable->startGlyphIndex) + 3);
                 break;
             }
         }
         // if we reach here, we didn't find a strike; unconditionally break
         // out of the while-loop block
         break;
     }
     mFontFace->ReleaseFontTable(tableContext);
     if (hasStrike) {
         return true;
     }
     // if we didn't find a real strike, check if the font calls for scaling
     // another bitmap to this size
     hr = mFontFace->TryGetFontTable(DWRITE_MAKE_OPENTYPE_TAG('E', 'B', 'S', 'C'),
                                     (const void**)&tableData, &len,
                                     &tableContext, &exists);
     if (FAILED(hr)) {
         return false;
     }
     while (exists) {
         if (len < sizeof(EBSCHeader)) {
             break;
         }
         const EBSCHeader *hdr = reinterpret_cast<const EBSCHeader*>(tableData);
         if (hdr->version != 0x00020000) {
             break;
         }
         uint32_t numSizes = hdr->numSizes;
         if (numSizes > 0xffff) {
             break;
         }
         if (len < sizeof(EBSCHeader) + numSizes * sizeof(BitmapScaleTable)) {
             break;
         }
         const BitmapScaleTable *scaleTable =
             reinterpret_cast<const BitmapScaleTable*>(hdr + 1);
         for (uint32_t i = 0; i < numSizes; ++i, ++scaleTable) {
             if (scaleTable->ppemX == aSize && scaleTable->ppemY == aSize) {
                 hasStrike = true;
                 break;
             }
         }
         break;
     }
     mFontFace->ReleaseFontTable(tableContext);
     return hasStrike;
 }
 uint32_t
 gfxDWriteFont::GetSpaceGlyph()
 {
     UINT32 ucs = L' ';
     UINT16 glyph;
     HRESULT hr;
     hr = mFontFace->GetGlyphIndicesA(&ucs, 1, &glyph);
     if (FAILED(hr)) {
         return 0;
     }
     return glyph;
 }
 bool
 gfxDWriteFont::SetupCairoFont(gfxContext *aContext)
 {
     cairo_scaled_font_t *scaledFont = GetCairoScaledFont();
     if (cairo_scaled_font_status(scaledFont) != CAIRO_STATUS_SUCCESS) {
         // Don't cairo_set_scaled_font as that would propagate the error to
         // the cairo_t, precluding any further drawing.
         return false;
     }
     cairo_set_scaled_font(aContext->GetCairo(), scaledFont);
     return true;
 }
 bool
 gfxDWriteFont::IsValid()
 {
     return mFontFace != nullptr;
 }
 IDWriteFontFace*
 gfxDWriteFont::GetFontFace()
 {
     return  mFontFace.get();
 }
 cairo_font_face_t *
 gfxDWriteFont::CairoFontFace()
 {
     if (!mCairoFontFace) {
 #ifdef CAIRO_HAS_DWRITE_FONT
         mCairoFontFace =
             cairo_dwrite_font_face_create_for_dwrite_fontface(
             ((gfxDWriteFontEntry*)mFontEntry.get())->mFont, mFontFace);
 #endif
     }
     return mCairoFontFace;
 }
 cairo_scaled_font_t *
 gfxDWriteFont::GetCairoScaledFont()
 {
     if (!mScaledFont) {
         cairo_matrix_t sizeMatrix;
         cairo_matrix_t identityMatrix;
         cairo_matrix_init_scale(&sizeMatrix, mAdjustedSize, mAdjustedSize);
         cairo_matrix_init_identity(&identityMatrix);
         cairo_font_options_t *fontOptions = cairo_font_options_create();
         if (mNeedsOblique) {
             double skewfactor = OBLIQUE_SKEW_FACTOR;
             cairo_matrix_t style;
             cairo_matrix_init(&style,
 ,                //xx
 ,                //yx
                               -1 * skewfactor,  //xy
 ,                //yy
 ,                //x0
 );               //y0
             cairo_matrix_multiply(&sizeMatrix, &sizeMatrix, &style);
         }
         if (mAntialiasOption != kAntialiasDefault) {
             cairo_font_options_set_antialias(fontOptions,
                 GetCairoAntialiasOption(mAntialiasOption));
         }
         mScaledFont = cairo_scaled_font_create(CairoFontFace(),
                                                     &sizeMatrix,
                                                     &identityMatrix,
                                                     fontOptions);
         cairo_font_options_destroy(fontOptions);
         cairo_dwrite_scaled_font_allow_manual_show_glyphs(mScaledFont,
                                                           mAllowManualShowGlyphs);
         gfxDWriteFontEntry *fe =
             static_cast<gfxDWriteFontEntry*>(mFontEntry.get());
         cairo_dwrite_scaled_font_set_force_GDI_classic(mScaledFont,
                                                        GetForceGDIClassic());
     }
     NS_ASSERTION(mAdjustedSize == 0.0 ||
                  cairo_scaled_font_status(mScaledFont)
                    == CAIRO_STATUS_SUCCESS,
                  "Failed to make scaled font");
     return mScaledFont;
 }
 gfxFont::RunMetrics
 gfxDWriteFont::Measure(gfxTextRun *aTextRun,
                     uint32_t aStart, uint32_t aEnd,
                     BoundingBoxType aBoundingBoxType,
                     gfxContext *aRefContext,
                     Spacing *aSpacing)
 {
     gfxFont::RunMetrics metrics =
         gfxFont::Measure(aTextRun, aStart, aEnd,
                          aBoundingBoxType, aRefContext, aSpacing);
     // if aBoundingBoxType is LOOSE_INK_EXTENTS
     // and the underlying cairo font may be antialiased,
     // we can't trust Windows to have considered all the pixels
     // so we need to add "padding" to the bounds.
     // (see bugs 475968, 439831, compare also bug 445087)
     if (aBoundingBoxType == LOOSE_INK_EXTENTS &&
         mAntialiasOption != kAntialiasNone &&
         GetMeasuringMode() == DWRITE_MEASURING_MODE_GDI_CLASSIC &&
         metrics.mBoundingBox.width > 0) {
         metrics.mBoundingBox.x -= aTextRun->GetAppUnitsPerDevUnit();
         metrics.mBoundingBox.width += aTextRun->GetAppUnitsPerDevUnit() * 3;
     }
     return metrics;
 }
 bool
 gfxDWriteFont::ProvidesGlyphWidths()
 {
     return !mUseSubpixelPositions ||
            (mFontFace->GetSimulations() & DWRITE_FONT_SIMULATIONS_BOLD);
 }
 int32_t
 gfxDWriteFont::GetGlyphWidth(gfxContext *aCtx, uint16_t aGID)
 {
     if (!mGlyphWidths) {
         mGlyphWidths = new nsDataHashtable<nsUint32HashKey,int32_t>(200);
     }
     int32_t width = -1;
     if (mGlyphWidths->Get(aGID, &width)) {
         return width;
     }
     width = NS_lround(MeasureGlyphWidth(aGID) * 65536.0);
     mGlyphWidths->Put(aGID, width);
     return width;
 }
 TemporaryRef<GlyphRenderingOptions>
 gfxDWriteFont::GetGlyphRenderingOptions()
 {
   if (UsingClearType()) {
     return Factory::CreateDWriteGlyphRenderingOptions(
       gfxWindowsPlatform::GetPlatform()->GetRenderingParams(GetForceGDIClassic() ?
         gfxWindowsPlatform::TEXT_RENDERING_GDI_CLASSIC : gfxWindowsPlatform::TEXT_RENDERING_NORMAL));
   } else {
     return Factory::CreateDWriteGlyphRenderingOptions(gfxWindowsPlatform::GetPlatform()->
       GetRenderingParams(gfxWindowsPlatform::TEXT_RENDERING_NO_CLEARTYPE));
   }
 }
 bool
 gfxDWriteFont::GetForceGDIClassic()
 {
     return static_cast<gfxDWriteFontEntry*>(mFontEntry.get())->GetForceGDIClassic() &&
          cairo_dwrite_get_cleartype_rendering_mode() < 0 &&
          GetAdjustedSize() <=
             gfxDWriteFontList::PlatformFontList()->GetForceGDIClassicMaxFontSize();
 }
 DWRITE_MEASURING_MODE
 gfxDWriteFont::GetMeasuringMode()
 {
     return GetForceGDIClassic()
         ? DWRITE_MEASURING_MODE_GDI_CLASSIC
         : gfxWindowsPlatform::GetPlatform()->DWriteMeasuringMode();
 }
 gfxFloat
 gfxDWriteFont::MeasureGlyphWidth(uint16_t aGlyph)
 {
     DWRITE_GLYPH_METRICS metrics;
     HRESULT hr;
     if (mUseSubpixelPositions) {
         hr = mFontFace->GetDesignGlyphMetrics(&aGlyph, 1, &metrics, FALSE);
         if (SUCCEEDED(hr)) {
             return metrics.advanceWidth * mFUnitsConvFactor;
         }
     } else {
         hr = mFontFace->GetGdiCompatibleGlyphMetrics(
                   FLOAT(mAdjustedSize), 1.0f, nullptr,
                   GetMeasuringMode() == DWRITE_MEASURING_MODE_GDI_NATURAL,
                   &aGlyph, 1, &metrics, FALSE);
         if (SUCCEEDED(hr)) {
             return NS_lround(metrics.advanceWidth * mFUnitsConvFactor);
         }
     }
     return 0;
 }
 void
 gfxDWriteFont::AddSizeOfExcludingThis(MallocSizeOf aMallocSizeOf,
                                       FontCacheSizes* aSizes) const
 {
     gfxFont::AddSizeOfExcludingThis(aMallocSizeOf, aSizes);
     aSizes->mFontInstances += aMallocSizeOf(mMetrics);
     if (mGlyphWidths) {
         aSizes->mFontInstances +=
             mGlyphWidths->SizeOfExcludingThis(nullptr, aMallocSizeOf);
     }
 }
 void
 gfxDWriteFont::AddSizeOfIncludingThis(MallocSizeOf aMallocSizeOf,
                                       FontCacheSizes* aSizes) const
 {
     aSizes->mFontInstances += aMallocSizeOf(this);
     AddSizeOfExcludingThis(aMallocSizeOf, aSizes);
 }
 TemporaryRef<ScaledFont>
 gfxDWriteFont::GetScaledFont(mozilla::gfx::DrawTarget *aTarget)
 {
   bool wantCairo = aTarget->GetType() == BackendType::CAIRO;
   if (mAzureScaledFont && mAzureScaledFontIsCairo == wantCairo) {
     return mAzureScaledFont;
   }
   NativeFont nativeFont;
   nativeFont.mType = NativeFontType::DWRITE_FONT_FACE;
   nativeFont.mFont = GetFontFace();
   if (wantCairo) {
     mAzureScaledFont = Factory::CreateScaledFontWithCairo(nativeFont,
                                                         GetAdjustedSize(),
                                                         GetCairoScaledFont());
   } else {
     mAzureScaledFont = Factory::CreateScaledFontForNativeFont(nativeFont,
                                                             GetAdjustedSize());
   }
   mAzureScaledFontIsCairo = wantCairo;
   return mAzureScaledFont;
 }

The Tor Browser / annotate

gfx/thebes/gfxDWriteFonts.cpp@97036ab72558 (annotated)

gfx/thebes/gfxDWriteFonts.cpp