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/* -*- Mode: C++; tab-width: 20; indent-tabs-mode: nil; c-basic-offset: 2 -*-
* 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 <algorithm>
#include "gfxDWriteFontList.h"
#include "gfxContext.h"
#include "gfxTextRun.h"
#include "mozilla/gfx/Logging.h"
#include "mozilla/gfx/gfxVars.h"
#include "harfbuzz/hb.h"
#include "mozilla/FontPropertyTypes.h"
using namespace mozilla;
using namespace mozilla::gfx;
// 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
// Cleartype can be dynamically enabled/disabled, so we have to allow for
// dynamically updating it.
static BYTE GetSystemTextQuality() {
BOOL font_smoothing;
UINT smoothing_type;
if (!SystemParametersInfo(SPI_GETFONTSMOOTHING, 0, &font_smoothing, 0)) {
return DEFAULT_QUALITY;
}
if (font_smoothing) {
if (!SystemParametersInfo(SPI_GETFONTSMOOTHINGTYPE, 0, &smoothing_type,
0)) {
return DEFAULT_QUALITY;
}
if (smoothing_type == FE_FONTSMOOTHINGCLEARTYPE) {
return CLEARTYPE_QUALITY;
}
return ANTIALIASED_QUALITY;
}
return DEFAULT_QUALITY;
}
#ifndef SPI_GETFONTSMOOTHINGCONTRAST
# define SPI_GETFONTSMOOTHINGCONTRAST 0x200c
#endif
// "Retrieves a contrast value that is used in ClearType smoothing. Valid
// contrast values are from 1000 to 2200. The default value is 1400."
static FLOAT GetSystemGDIGamma() {
static FLOAT sGDIGamma = 0.0f;
if (!sGDIGamma) {
UINT value = 0;
if (!SystemParametersInfo(SPI_GETFONTSMOOTHINGCONTRAST, 0, &value, 0) ||
value < 1000 || value > 2200) {
value = 1400;
}
sGDIGamma = value / 1000.0f;
}
return sGDIGamma;
}
////////////////////////////////////////////////////////////////////////////////
// gfxDWriteFont
gfxDWriteFont::gfxDWriteFont(const RefPtr<UnscaledFontDWrite>& aUnscaledFont,
gfxFontEntry* aFontEntry,
const gfxFontStyle* aFontStyle,
RefPtr<IDWriteFontFace> aFontFace,
AntialiasOption anAAOption)
: gfxFont(aUnscaledFont, aFontEntry, aFontStyle, anAAOption),
mFontFace(aFontFace ? aFontFace : aUnscaledFont->GetFontFace()),
mMetrics(nullptr),
mUseSubpixelPositions(false),
mAllowManualShowGlyphs(true),
mAzureScaledFontUsedClearType(false) {
// If the IDWriteFontFace1 interface is available, we can use that for
// faster glyph width retrieval.
mFontFace->QueryInterface(__uuidof(IDWriteFontFace1),
(void**)getter_AddRefs(mFontFace1));
ComputeMetrics(anAAOption);
}
gfxDWriteFont::~gfxDWriteFont() { delete mMetrics; }
void gfxDWriteFont::UpdateSystemTextQuality() {
BYTE newQuality = GetSystemTextQuality();
if (gfxVars::SystemTextQuality() != newQuality) {
gfxVars::SetSystemTextQuality(newQuality);
}
}
void gfxDWriteFont::SystemTextQualityChanged() {
// If ClearType status has changed, update our value,
Factory::SetSystemTextQuality(gfxVars::SystemTextQuality());
// flush cached stuff that depended on the old setting, and force
// reflow everywhere to ensure we are using correct glyph metrics.
gfxPlatform::FlushFontAndWordCaches();
gfxPlatform::ForceGlobalReflow();
}
UniquePtr<gfxFont> gfxDWriteFont::CopyWithAntialiasOption(
AntialiasOption anAAOption) {
auto entry = static_cast<gfxDWriteFontEntry*>(mFontEntry.get());
RefPtr<UnscaledFontDWrite> unscaledFont =
static_cast<UnscaledFontDWrite*>(mUnscaledFont.get());
return MakeUnique<gfxDWriteFont>(unscaledFont, entry, &mStyle, mFontFace,
anAAOption);
}
const gfxFont::Metrics& gfxDWriteFont::GetHorizontalMetrics() {
return *mMetrics;
}
bool gfxDWriteFont::GetFakeMetricsForArialBlack(
DWRITE_FONT_METRICS* aFontMetrics) {
gfxFontStyle style(mStyle);
style.weight = FontWeight(700);
gfxFontEntry* fe = gfxPlatformFontList::PlatformFontList()->FindFontForFamily(
"Arial"_ns, &style);
if (!fe || fe == mFontEntry) {
return false;
}
RefPtr<gfxFont> font = fe->FindOrMakeFont(&style);
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().Min() == FontWeight(900) &&
mFontEntry->Weight().Max() == FontWeight(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->capHeight = fontMetrics.capHeight * mFUnitsConvFactor;
mMetrics->maxAscent = round(fontMetrics.ascent * mFUnitsConvFactor);
mMetrics->maxDescent = round(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 MetricsHeader* hhea = reinterpret_cast<const MetricsHeader*>(
hb_blob_get_data(hheaTable, &len));
if (len >= sizeof(MetricsHeader)) {
mMetrics->maxAdvance =
uint16_t(hhea->advanceWidthMax) * mFUnitsConvFactor;
}
}
mMetrics->internalLeading =
std::max(mMetrics->maxHeight - mMetrics->emHeight, 0.0);
mMetrics->externalLeading = ceil(fontMetrics.lineGap * mFUnitsConvFactor);
UINT32 ucs = L' ';
UINT16 glyph;
if (SUCCEEDED(mFontFace->GetGlyphIndices(&ucs, 1, &glyph)) && glyph != 0) {
mSpaceGlyph = glyph;
mMetrics->spaceWidth = MeasureGlyphWidth(glyph);
} else {
mMetrics->spaceWidth = 0;
}
// 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;
}
}
}
if (mMetrics->aveCharWidth < 1) {
ucs = L'x';
if (SUCCEEDED(mFontFace->GetGlyphIndices(&ucs, 1, &glyph)) && glyph != 0) {
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->GetGlyphIndices(&ucs, 1, &glyph)) && glyph != 0) {
mMetrics->zeroWidth = MeasureGlyphWidth(glyph);
} else {
mMetrics->zeroWidth = -1.0; // indicates not found
}
mMetrics->underlineOffset = fontMetrics.underlinePosition * mFUnitsConvFactor;
mMetrics->underlineSize = fontMetrics.underlineThickness * mFUnitsConvFactor;
mMetrics->strikeoutOffset =
fontMetrics.strikethroughPosition * mFUnitsConvFactor;
mMetrics->strikeoutSize =
fontMetrics.strikethroughThickness * mFUnitsConvFactor;
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 zeroWidth: %f\n",
mMetrics->spaceWidth, mMetrics->aveCharWidth, mMetrics->zeroWidth);
printf(" xHeight: %f capHeight: %f\n", mMetrics->xHeight, mMetrics->capHeight);
printf(" uOff: %f uSize: %f stOff: %f stSize: %f\n",
mMetrics->underlineOffset, mMetrics->underlineSize, mMetrics->strikeoutOffset, mMetrics->strikeoutSize);
#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;
}
bool gfxDWriteFont::IsValid() const { return mFontFace != nullptr; }
IDWriteFontFace* gfxDWriteFont::GetFontFace() { return mFontFace.get(); }
gfxFont::RunMetrics gfxDWriteFont::Measure(const gfxTextRun* aTextRun,
uint32_t aStart, uint32_t aEnd,
BoundingBoxType aBoundingBoxType,
DrawTarget* aRefDrawTarget,
Spacing* aSpacing,
gfx::ShapedTextFlags aOrientation) {
gfxFont::RunMetrics metrics =
gfxFont::Measure(aTextRun, aStart, aEnd, aBoundingBoxType, aRefDrawTarget,
aSpacing, aOrientation);
// 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.MoveByX(-aTextRun->GetAppUnitsPerDevUnit());
metrics.mBoundingBox.SetWidth(metrics.mBoundingBox.Width() +
aTextRun->GetAppUnitsPerDevUnit() * 3);
}
return metrics;
}
bool gfxDWriteFont::ProvidesGlyphWidths() const {
return !mUseSubpixelPositions ||
(mFontFace->GetSimulations() & DWRITE_FONT_SIMULATIONS_BOLD) ||
(((gfxDWriteFontEntry*)(GetFontEntry()))->HasVariations() &&
!mStyle.variationSettings.IsEmpty());
}
int32_t gfxDWriteFont::GetGlyphWidth(uint16_t aGID) {
if (!mGlyphWidths) {
mGlyphWidths = MakeUnique<nsDataHashtable<nsUint32HashKey, int32_t>>(128);
}
int32_t width = -1;
if (mGlyphWidths->Get(aGID, &width)) {
return width;
}
width = NS_lround(MeasureGlyphWidth(aGID) * 65536.0);
mGlyphWidths->Put(aGID, width);
return width;
}
bool gfxDWriteFont::GetForceGDIClassic() const {
return static_cast<gfxDWriteFontEntry*>(mFontEntry.get())
->GetForceGDIClassic() &&
cairo_dwrite_get_cleartype_rendering_mode() < 0 &&
GetAdjustedSize() <= gfxDWriteFontList::PlatformFontList()
->GetForceGDIClassicMaxFontSize();
}
DWRITE_MEASURING_MODE
gfxDWriteFont::GetMeasuringMode() const {
return GetForceGDIClassic()
? DWRITE_MEASURING_MODE_GDI_CLASSIC
: gfxWindowsPlatform::GetPlatform()->DWriteMeasuringMode();
}
gfxFloat gfxDWriteFont::MeasureGlyphWidth(uint16_t aGlyph) {
MOZ_SEH_TRY {
HRESULT hr;
if (mFontFace1) {
int32_t advance;
if (mUseSubpixelPositions) {
hr = mFontFace1->GetDesignGlyphAdvances(1, &aGlyph, &advance, FALSE);
if (SUCCEEDED(hr)) {
return advance * mFUnitsConvFactor;
}
} else {
hr = mFontFace1->GetGdiCompatibleGlyphAdvances(
FLOAT(mAdjustedSize), 1.0f, nullptr,
GetMeasuringMode() == DWRITE_MEASURING_MODE_GDI_NATURAL, FALSE, 1,
&aGlyph, &advance);
if (SUCCEEDED(hr)) {
return NS_lround(advance * mFUnitsConvFactor);
}
}
} else {
DWRITE_GLYPH_METRICS metrics;
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);
}
}
}
}
MOZ_SEH_EXCEPT(EXCEPTION_EXECUTE_HANDLER) {
// Exception (e.g. disk i/o error) occurred when DirectWrite tried to use
// the font resource; possibly a failing drive or similar hardware issue.
// Mark the font as invalid, and wipe the fontEntry's charmap so that font
// selection will skip it; we'll use a fallback font instead.
mIsValid = false;
GetFontEntry()->mCharacterMap = new gfxCharacterMap();
GetFontEntry()->mShmemCharacterMap = nullptr;
gfxCriticalError() << "Exception occurred measuring glyph width for "
<< GetFontEntry()->Name().get();
}
return 0.0;
}
bool gfxDWriteFont::GetGlyphBounds(uint16_t aGID, gfxRect* aBounds,
bool aTight) {
DWRITE_GLYPH_METRICS m;
HRESULT hr = mFontFace->GetDesignGlyphMetrics(&aGID, 1, &m, FALSE);
if (FAILED(hr)) {
return false;
}
gfxRect bounds(m.leftSideBearing, m.topSideBearing - m.verticalOriginY,
m.advanceWidth - m.leftSideBearing - m.rightSideBearing,
m.advanceHeight - m.topSideBearing - m.bottomSideBearing);
bounds.Scale(mFUnitsConvFactor);
// GetDesignGlyphMetrics returns 'ideal' glyph metrics, we need to pad to
// account for antialiasing.
if (!aTight && !aBounds->IsEmpty()) {
bounds.Inflate(1.0, 0.0);
}
*aBounds = bounds;
return true;
}
void gfxDWriteFont::AddSizeOfExcludingThis(MallocSizeOf aMallocSizeOf,
FontCacheSizes* aSizes) const {
gfxFont::AddSizeOfExcludingThis(aMallocSizeOf, aSizes);
aSizes->mFontInstances += aMallocSizeOf(mMetrics);
if (mGlyphWidths) {
aSizes->mFontInstances +=
mGlyphWidths->ShallowSizeOfIncludingThis(aMallocSizeOf);
}
}
void gfxDWriteFont::AddSizeOfIncludingThis(MallocSizeOf aMallocSizeOf,
FontCacheSizes* aSizes) const {
aSizes->mFontInstances += aMallocSizeOf(this);
AddSizeOfExcludingThis(aMallocSizeOf, aSizes);
}
already_AddRefed<ScaledFont> gfxDWriteFont::GetScaledFont(
mozilla::gfx::DrawTarget* aTarget) {
if (mAzureScaledFontUsedClearType != UsingClearType()) {
mAzureScaledFont = nullptr;
}
if (!mAzureScaledFont) {
gfxDWriteFontEntry* fe = static_cast<gfxDWriteFontEntry*>(mFontEntry.get());
bool forceGDI = GetForceGDIClassic();
// params may be null, if initialization failed
IDWriteRenderingParams* params =
gfxWindowsPlatform::GetPlatform()->GetRenderingParams(
UsingClearType()
? (forceGDI ? gfxWindowsPlatform::TEXT_RENDERING_GDI_CLASSIC
: gfxWindowsPlatform::TEXT_RENDERING_NORMAL)
: gfxWindowsPlatform::TEXT_RENDERING_NO_CLEARTYPE);
DWRITE_RENDERING_MODE renderingMode =
params ? params->GetRenderingMode() : DWRITE_RENDERING_MODE_DEFAULT;
FLOAT gamma = params ? params->GetGamma() : 2.2;
FLOAT contrast = params ? params->GetEnhancedContrast() : 1.0;
FLOAT clearTypeLevel = params ? params->GetClearTypeLevel() : 1.0;
if (forceGDI || renderingMode == DWRITE_RENDERING_MODE_GDI_CLASSIC) {
renderingMode = DWRITE_RENDERING_MODE_GDI_CLASSIC;
gamma = GetSystemGDIGamma();
contrast = 0.0f;
}
bool useEmbeddedBitmap =
(renderingMode == DWRITE_RENDERING_MODE_DEFAULT ||
renderingMode == DWRITE_RENDERING_MODE_GDI_CLASSIC) &&
fe->IsCJKFont() && HasBitmapStrikeForSize(NS_lround(mAdjustedSize));
const gfxFontStyle* fontStyle = GetStyle();
mAzureScaledFont = Factory::CreateScaledFontForDWriteFont(
mFontFace, fontStyle, GetUnscaledFont(), GetAdjustedSize(),
useEmbeddedBitmap, (int)renderingMode, params, gamma, contrast,
clearTypeLevel);
if (!mAzureScaledFont) {
return nullptr;
}
InitializeScaledFont();
mAzureScaledFontUsedClearType = UsingClearType();
}
RefPtr<ScaledFont> scaledFont(mAzureScaledFont);
return scaledFont.forget();
}
bool gfxDWriteFont::ShouldRoundXOffset(cairo_t* aCairo) const {
// show_glyphs is implemented on the font and so is used for all Cairo
// surface types; however, it may pixel-snap depending on the dwrite
// rendering mode
return GetForceGDIClassic() ||
gfxWindowsPlatform::GetPlatform()->DWriteMeasuringMode() !=
DWRITE_MEASURING_MODE_NATURAL;
}