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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
#include "gfxMacFont.h"
#include "mozilla/MemoryReporting.h"
#include "mozilla/Sprintf.h"
#include "mozilla/StaticPrefs_gfx.h"
#include "mozilla/gfx/ScaledFontMac.h"
#include <algorithm>
#include "CoreTextFontList.h"
#include "gfxCoreTextShaper.h"
#include "gfxPlatformMac.h"
#include "gfxContext.h"
#include "gfxFontUtils.h"
#include "gfxHarfBuzzShaper.h"
#include "gfxFontConstants.h"
#include "gfxTextRun.h"
#include "gfxUtils.h"
#include "AppleUtils.h"
#include "cairo-quartz.h"
using namespace mozilla;
using namespace mozilla::gfx;
template <class T>
struct TagEquals {
bool Equals(const T& aIter, uint32_t aTag) const {
return aIter.mTag == aTag;
}
};
gfxMacFont::gfxMacFont(const RefPtr<UnscaledFontMac>& aUnscaledFont,
CTFontEntry* aFontEntry, const gfxFontStyle* aFontStyle)
: gfxFont(aUnscaledFont, aFontEntry, aFontStyle),
mCGFont(nullptr),
mCTFont(nullptr),
mVariationFont(aFontEntry->HasVariations()) {
mApplySyntheticBold = aFontStyle->NeedsSyntheticBold(aFontEntry);
if (mVariationFont) {
CGFontRef baseFont = aUnscaledFont->GetFont();
if (!baseFont) {
mIsValid = false;
return;
}
// Get the variation settings needed to instantiate the fontEntry
// for a particular fontStyle.
AutoTArray<gfxFontVariation, 4> vars;
aFontEntry->GetVariationsForStyle(vars, *aFontStyle);
if (aFontEntry->HasOpticalSize()) {
// Because of a Core Text bug, we need to ensure that if the font has
// an 'opsz' axis, it is always explicitly set, and NOT to the font's
// We record the result of searching the font's axes in the font entry,
// so that this only has to be done by the first instance created for
// a given font resource.
const uint32_t kOpszTag = HB_TAG('o', 'p', 's', 'z');
const float kOpszFudgeAmount = 0.01f;
// Record the opsz axis details in the font entry, if not already done.
if (!aFontEntry->mOpszAxis.mTag) {
AutoTArray<gfxFontVariationAxis, 4> axes;
aFontEntry->GetVariationAxes(axes);
auto index =
axes.IndexOf(kOpszTag, 0, TagEquals<gfxFontVariationAxis>());
MOZ_ASSERT(index != axes.NoIndex);
if (index != axes.NoIndex) {
const auto& axis = axes[index];
aFontEntry->mOpszAxis = axis;
// Pick a slightly-adjusted version of the default that we'll
// use to work around Core Text's habit of ignoring any attempt
// to explicitly set the default value.
aFontEntry->mAdjustedDefaultOpsz =
axis.mDefaultValue == axis.mMinValue
? axis.mDefaultValue + kOpszFudgeAmount
: axis.mDefaultValue - kOpszFudgeAmount;
}
}
// Add 'opsz' if not present, or tweak its value if it looks too close
// to the default (after clamping to the font's available range).
auto index = vars.IndexOf(kOpszTag, 0, TagEquals<gfxFontVariation>());
if (index == vars.NoIndex) {
// No explicit opsz; set to the font's default.
vars.AppendElement(
gfxFontVariation{kOpszTag, aFontEntry->mAdjustedDefaultOpsz});
} else {
// An 'opsz' value was already present; use it, but adjust if necessary
// to a "safe" value that Core Text won't ignore.
auto& value = vars[index].mValue;
auto& axis = aFontEntry->mOpszAxis;
value = fmin(fmax(value, axis.mMinValue), axis.mMaxValue);
if (std::abs(value - axis.mDefaultValue) < kOpszFudgeAmount) {
value = aFontEntry->mAdjustedDefaultOpsz;
}
}
}
mCGFont = UnscaledFontMac::CreateCGFontWithVariations(
baseFont, aUnscaledFont->CGAxesCache(), aUnscaledFont->CTAxesCache(),
vars.Length(), vars.Elements());
if (!mCGFont) {
::CFRetain(baseFont);
mCGFont = baseFont;
}
} else {
mCGFont = aUnscaledFont->GetFont();
if (!mCGFont) {
mIsValid = false;
return;
}
::CFRetain(mCGFont);
}
// InitMetrics will handle the sizeAdjust factor and set mAdjustedSize
InitMetrics();
if (!mIsValid) {
return;
}
// turn off font anti-aliasing based on user pref setting
if (mAdjustedSize <=
(gfxFloat)gfxPlatformMac::GetPlatform()->GetAntiAliasingThreshold()) {
mAntialiasOption = kAntialiasNone;
} else if (mStyle.useGrayscaleAntialiasing) {
mAntialiasOption = kAntialiasGrayscale;
}
}
gfxMacFont::~gfxMacFont() {
if (mCGFont) {
::CFRelease(mCGFont);
}
if (mCTFont) {
::CFRelease(mCTFont);
}
}
bool gfxMacFont::ShapeText(DrawTarget* aDrawTarget, const char16_t* aText,
uint32_t aOffset, uint32_t aLength, Script aScript,
nsAtom* aLanguage, bool aVertical,
RoundingFlags aRounding,
gfxShapedText* aShapedText) {
if (!mIsValid) {
NS_WARNING("invalid font! expect incorrect text rendering");
return false;
}
// Currently, we don't support vertical shaping via CoreText,
// so we ignore RequiresAATLayout if vertical is requested.
auto ctFontEntry = static_cast<CTFontEntry*>(GetFontEntry());
if (ctFontEntry->RequiresAATLayout() && !aVertical &&
StaticPrefs::gfx_font_rendering_coretext_enabled()) {
if (!mCoreTextShaper) {
mCoreTextShaper = MakeUnique<gfxCoreTextShaper>(this);
}
if (mCoreTextShaper->ShapeText(aDrawTarget, aText, aOffset, aLength,
aScript, aLanguage, aVertical, aRounding,
aShapedText)) {
PostShapingFixup(aDrawTarget, aText, aOffset, aLength, aVertical,
aShapedText);
if (ctFontEntry->HasTrackingTable()) {
// Convert font size from device pixels back to CSS px
// to use in selecting tracking value
float trackSize = GetAdjustedSize() *
aShapedText->GetAppUnitsPerDevUnit() /
AppUnitsPerCSSPixel();
float tracking =
ctFontEntry->TrackingForCSSPx(trackSize) * mFUnitsConvFactor;
// Applying tracking is a lot like the adjustment we do for
// synthetic bold: we want to apply between clusters, not to
// non-spacing glyphs within a cluster. So we can reuse that
// helper here.
aShapedText->ApplyTrackingToClusters(tracking, aOffset, aLength);
}
return true;
}
}
return gfxFont::ShapeText(aDrawTarget, aText, aOffset, aLength, aScript,
aLanguage, aVertical, aRounding, aShapedText);
}
gfxFont::RunMetrics gfxMacFont::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 not TIGHT_HINTED_OUTLINE_EXTENTS then we need to add
// a pixel column each side of the bounding box in case of antialiasing
// "bleed"
if (aBoundingBoxType != TIGHT_HINTED_OUTLINE_EXTENTS &&
metrics.mBoundingBox.width > 0) {
metrics.mBoundingBox.x -= aTextRun->GetAppUnitsPerDevUnit();
metrics.mBoundingBox.width += aTextRun->GetAppUnitsPerDevUnit() * 2;
}
return metrics;
}
void gfxMacFont::InitMetrics() {
mIsValid = false;
::memset(&mMetrics, 0, sizeof(mMetrics));
uint32_t upem = 0;
// try to get unitsPerEm from sfnt head table, to avoid calling CGFont
// return the true value for OpenType/CFF fonts (it normalizes to 1000,
// which then leads to metrics errors when we read the 'hmtx' table to
AutoCFRelease<CFDataRef> headData =
::CGFontCopyTableForTag(mCGFont, TRUETYPE_TAG('h', 'e', 'a', 'd'));
if (headData) {
if (size_t(::CFDataGetLength(headData)) >= sizeof(HeadTable)) {
const HeadTable* head =
reinterpret_cast<const HeadTable*>(::CFDataGetBytePtr(headData));
upem = head->unitsPerEm;
}
}
if (!upem) {
upem = ::CGFontGetUnitsPerEm(mCGFont);
}
if (upem < 16 || upem > 16384) {
#ifdef DEBUG
char warnBuf[1024];
SprintfLiteral(warnBuf,
"Bad font metrics for: %s (invalid unitsPerEm value)",
mFontEntry->Name().get());
NS_WARNING(warnBuf);
#endif
return;
}
// Apply any size-adjust from the font enty to the given size; this may be
// re-adjusted below if font-size-adjust is in effect.
mAdjustedSize = GetAdjustedSize();
mFUnitsConvFactor = mAdjustedSize / upem;
// For CFF fonts, when scaling values read from CGFont* APIs, we need to
// use CG's idea of unitsPerEm, which may differ from the "true" value in
gfxFloat cgConvFactor;
if (static_cast<CTFontEntry*>(mFontEntry.get())->IsCFF()) {
cgConvFactor = mAdjustedSize / ::CGFontGetUnitsPerEm(mCGFont);
} else {
cgConvFactor = mFUnitsConvFactor;
}
// Try to read 'sfnt' metrics; for local, non-sfnt fonts ONLY, fall back to
// platform APIs. The InitMetrics...() functions will set mIsValid on success.
if (!InitMetricsFromSfntTables(mMetrics) &&
(!mFontEntry->IsUserFont() || mFontEntry->IsLocalUserFont())) {
InitMetricsFromPlatform();
}
if (!mIsValid) {
return;
}
if (mMetrics.xHeight == 0.0) {
mMetrics.xHeight = ::CGFontGetXHeight(mCGFont) * cgConvFactor;
}
if (mMetrics.capHeight == 0.0) {
mMetrics.capHeight = ::CGFontGetCapHeight(mCGFont) * cgConvFactor;
}
AutoCFRelease<CFDataRef> cmap =
::CGFontCopyTableForTag(mCGFont, TRUETYPE_TAG('c', 'm', 'a', 'p'));
uint32_t glyphID;
mMetrics.zeroWidth = GetCharWidth(cmap, '0', &glyphID, cgConvFactor);
if (glyphID == 0) {
mMetrics.zeroWidth = -1.0; // indicates not found
}
if (FontSizeAdjust::Tag(mStyle.sizeAdjustBasis) !=
FontSizeAdjust::Tag::None &&
mStyle.sizeAdjust >= 0.0 && GetAdjustedSize() > 0.0) {
// apply font-size-adjust, and recalculate metrics
gfxFloat aspect;
switch (FontSizeAdjust::Tag(mStyle.sizeAdjustBasis)) {
default:
MOZ_ASSERT_UNREACHABLE("unhandled sizeAdjustBasis?");
aspect = 0.0;
break;
case FontSizeAdjust::Tag::ExHeight:
aspect = mMetrics.xHeight / mAdjustedSize;
break;
case FontSizeAdjust::Tag::CapHeight:
aspect = mMetrics.capHeight / mAdjustedSize;
break;
case FontSizeAdjust::Tag::ChWidth:
aspect =
mMetrics.zeroWidth < 0.0 ? 0.5 : mMetrics.zeroWidth / mAdjustedSize;
break;
case FontSizeAdjust::Tag::IcWidth:
case FontSizeAdjust::Tag::IcHeight: {
bool vertical = FontSizeAdjust::Tag(mStyle.sizeAdjustBasis) ==
FontSizeAdjust::Tag::IcHeight;
gfxFloat advance = GetCharAdvance(kWaterIdeograph, vertical);
aspect = advance > 0.0 ? advance / mAdjustedSize : 1.0;
break;
}
}
if (aspect > 0.0) {
// If we created a shaper above (to measure glyphs), discard it so we
// get a new one for the adjusted scaling.
delete mHarfBuzzShaper.exchange(nullptr);
mAdjustedSize = mStyle.GetAdjustedSize(aspect);
mFUnitsConvFactor = mAdjustedSize / upem;
if (static_cast<CTFontEntry*>(mFontEntry.get())->IsCFF()) {
cgConvFactor = mAdjustedSize / ::CGFontGetUnitsPerEm(mCGFont);
} else {
cgConvFactor = mFUnitsConvFactor;
}
mMetrics.xHeight = 0.0;
if (!InitMetricsFromSfntTables(mMetrics) &&
(!mFontEntry->IsUserFont() || mFontEntry->IsLocalUserFont())) {
InitMetricsFromPlatform();
}
if (!mIsValid) {
// this shouldn't happen, as we succeeded earlier before applying
// the size-adjust factor! But check anyway, for paranoia's sake.
return;
}
// Update metrics from the re-scaled font.
if (mMetrics.xHeight == 0.0) {
mMetrics.xHeight = ::CGFontGetXHeight(mCGFont) * cgConvFactor;
}
if (mMetrics.capHeight == 0.0) {
mMetrics.capHeight = ::CGFontGetCapHeight(mCGFont) * cgConvFactor;
}
mMetrics.zeroWidth = GetCharWidth(cmap, '0', &glyphID, cgConvFactor);
if (glyphID == 0) {
mMetrics.zeroWidth = -1.0; // indicates not found
}
}
}
// Once we reach here, we've got basic metrics and set mIsValid = TRUE;
// there should be no further points of actual failure in InitMetrics().
// (If one is introduced, be sure to reset mIsValid to FALSE!)
mMetrics.emHeight = mAdjustedSize;
// Measure/calculate additional metrics, independent of whether we used
// the tables directly or ATS metrics APIs
if (mMetrics.aveCharWidth <= 0) {
mMetrics.aveCharWidth = GetCharWidth(cmap, 'x', &glyphID, cgConvFactor);
if (glyphID == 0) {
// we didn't find 'x', so use maxAdvance rather than zero
mMetrics.aveCharWidth = mMetrics.maxAdvance;
}
}
mMetrics.spaceWidth = GetCharWidth(cmap, ' ', &glyphID, cgConvFactor);
if (glyphID == 0) {
// no space glyph?!
mMetrics.spaceWidth = mMetrics.aveCharWidth;
}
mSpaceGlyph = glyphID;
mMetrics.ideographicWidth =
GetCharWidth(cmap, kWaterIdeograph, &glyphID, cgConvFactor);
if (glyphID == 0) {
// Indicate "not found".
mMetrics.ideographicWidth = -1.0;
}
CalculateDerivedMetrics(mMetrics);
SanitizeMetrics(&mMetrics, mFontEntry->mIsBadUnderlineFont);
if (ApplySyntheticBold()) {
auto delta = GetSyntheticBoldOffset();
mMetrics.spaceWidth += delta;
mMetrics.aveCharWidth += delta;
mMetrics.maxAdvance += delta;
if (mMetrics.zeroWidth > 0) {
mMetrics.zeroWidth += delta;
}
if (mMetrics.ideographicWidth > 0) {
mMetrics.ideographicWidth += delta;
}
}
#if 0
fprintf (stderr, "Font: %p (%s) size: %f\n", this,
NS_ConvertUTF16toUTF8(GetName()).get(), mStyle.size);
// fprintf (stderr, " fbounds.origin.x %f y %f size.width %f height %f\n", fbounds.origin.x, fbounds.origin.y, fbounds.size.width, fbounds.size.height);
fprintf (stderr, " emHeight: %f emAscent: %f emDescent: %f\n", mMetrics.emHeight, mMetrics.emAscent, mMetrics.emDescent);
fprintf (stderr, " maxAscent: %f maxDescent: %f maxAdvance: %f\n", mMetrics.maxAscent, mMetrics.maxDescent, mMetrics.maxAdvance);
fprintf (stderr, " internalLeading: %f externalLeading: %f\n", mMetrics.internalLeading, mMetrics.externalLeading);
fprintf (stderr, " spaceWidth: %f aveCharWidth: %f xHeight: %f capHeight: %f\n", mMetrics.spaceWidth, mMetrics.aveCharWidth, mMetrics.xHeight, mMetrics.capHeight);
fprintf (stderr, " uOff: %f uSize: %f stOff: %f stSize: %f\n", mMetrics.underlineOffset, mMetrics.underlineSize, mMetrics.strikeoutOffset, mMetrics.strikeoutSize);
#endif
}
gfxFloat gfxMacFont::GetCharWidth(CFDataRef aCmap, char16_t aUniChar,
uint32_t* aGlyphID, gfxFloat aConvFactor) {
CGGlyph glyph = 0;
if (aCmap) {
glyph = gfxFontUtils::MapCharToGlyph(::CFDataGetBytePtr(aCmap),
::CFDataGetLength(aCmap), aUniChar);
}
if (aGlyphID) {
*aGlyphID = glyph;
}
if (glyph) {
int advance;
if (::CGFontGetGlyphAdvances(mCGFont, &glyph, 1, &advance)) {
return advance * aConvFactor;
}
}
return 0;
}
int32_t gfxMacFont::GetGlyphWidth(uint16_t aGID) {
if (mVariationFont) {
// CoreGraphics glyph advance API. This is inferior for 'sbix'
// fonts, but those won't have variations, so it's OK.
int cgAdvance;
if (::CGFontGetGlyphAdvances(mCGFont, &aGID, 1, &cgAdvance)) {
return cgAdvance * mFUnitsConvFactor * 0x10000;
}
}
if (!mCTFont) {
bool isInstalledFont =
!mFontEntry->IsUserFont() || mFontEntry->IsLocalUserFont();
mCTFont = CreateCTFontFromCGFontWithVariations(mCGFont, mAdjustedSize,
isInstalledFont);
if (!mCTFont) { // shouldn't happen, but let's be safe
NS_WARNING("failed to create CTFontRef to measure glyph width");
return 0;
}
}
CGSize advance;
::CTFontGetAdvancesForGlyphs(mCTFont, kCTFontOrientationDefault, &aGID,
&advance, 1);
return advance.width * 0x10000;
}
bool gfxMacFont::GetGlyphBounds(uint16_t aGID, gfxRect* aBounds, bool aTight) {
CGRect bb;
if (!::CGFontGetGlyphBBoxes(mCGFont, &aGID, 1, &bb)) {
return false;
}
// broken fonts can return incorrect bounds for some null characters,
if (bb.origin.x == -32767 && bb.origin.y == -32767 &&
bb.size.width == 65534 && bb.size.height == 65534) {
*aBounds = gfxRect(0, 0, 0, 0);
return true;
}
gfxRect bounds(bb.origin.x, -(bb.origin.y + bb.size.height), bb.size.width,
bb.size.height);
bounds.Scale(mFUnitsConvFactor);
// For bitmap fonts (like Apple Color Emoji), CoreGraphics does not return
// accurate bounds, so to try and avoid clipping when the bounds are used
// to determine the area to render (e.g. when implementing canvas2d filters),
// we inflate the bounds based on global metrics from the font.
if (GetFontEntry()->HasColorBitmapTable()) {
aBounds->x = std::min(bounds.x, 0.0);
aBounds->width = std::max(bounds.width, mMetrics.maxAdvance);
// Note that y-coordinates are downwards here, and bounds.y is MINUS the
// glyph ascent as it measures from the baseline.
aBounds->y = std::min(bounds.y, -mMetrics.maxAscent);
aBounds->height =
std::max(bounds.YMost(), mMetrics.maxDescent) - aBounds->y;
} else {
*aBounds = bounds;
}
return true;
}
// Try to initialize font metrics via platform APIs (CG/CT),
// and set mIsValid = TRUE on success.
// We ONLY call this for local (platform) fonts that are not sfnt format;
// for sfnts, including ALL downloadable fonts, we prefer to use
// InitMetricsFromSfntTables and avoid platform APIs.
void gfxMacFont::InitMetricsFromPlatform() {
AutoCFRelease<CTFontRef> ctFont =
::CTFontCreateWithGraphicsFont(mCGFont, mAdjustedSize, nullptr, nullptr);
if (!ctFont) {
return;
}
mMetrics.underlineOffset = ::CTFontGetUnderlinePosition(ctFont);
mMetrics.underlineSize = ::CTFontGetUnderlineThickness(ctFont);
mMetrics.externalLeading = ::CTFontGetLeading(ctFont);
mMetrics.maxAscent = ::CTFontGetAscent(ctFont);
mMetrics.maxDescent = ::CTFontGetDescent(ctFont);
// this is not strictly correct, but neither CTFont nor CGFont seems to
// provide maxAdvance, unless we were to iterate over all the glyphs
// (which isn't worth the cost here)
CGRect r = ::CTFontGetBoundingBox(ctFont);
mMetrics.maxAdvance = r.size.width;
// aveCharWidth is also not provided, so leave it at zero
// (fallback code in gfxMacFont::InitMetrics will then try measuring 'x');
// this could lead to less-than-"perfect" text field sizing when width is
// specified as a number of characters, and the font in use is a non-sfnt
// legacy font, but that's a sufficiently obscure edge case that we can
// ignore the potential discrepancy.
mMetrics.aveCharWidth = 0;
mMetrics.xHeight = ::CTFontGetXHeight(ctFont);
mMetrics.capHeight = ::CTFontGetCapHeight(ctFont);
mIsValid = true;
}
already_AddRefed<ScaledFont> gfxMacFont::GetScaledFont(
const TextRunDrawParams& aRunParams) {
if (ScaledFont* scaledFont = mAzureScaledFont) {
return do_AddRef(scaledFont);
}
gfxFontEntry* fe = GetFontEntry();
bool hasColorGlyphs = fe->HasColorBitmapTable() || fe->TryGetColorGlyphs();
RefPtr<ScaledFont> newScaledFont = Factory::CreateScaledFontForMacFont(
GetCGFontRef(), GetUnscaledFont(), GetAdjustedSize(),
!mStyle.useGrayscaleAntialiasing, ApplySyntheticBold(), hasColorGlyphs);
if (!newScaledFont) {
return nullptr;
}
InitializeScaledFont(newScaledFont);
if (mAzureScaledFont.compareExchange(nullptr, newScaledFont.get())) {
Unused << newScaledFont.forget();
}
ScaledFont* scaledFont = mAzureScaledFont;
return do_AddRef(scaledFont);
}
bool gfxMacFont::ShouldRoundXOffset(cairo_t* aCairo) const {
// Quartz surfaces implement show_glyphs for Quartz fonts
return aCairo && cairo_surface_get_type(cairo_get_target(aCairo)) !=
CAIRO_SURFACE_TYPE_QUARTZ;
}
bool gfxMacFont::UseNativeColrFontSupport() const {
/*
auto* colr = GetFontEntry()->GetCOLR();
if (colr && COLRFonts::GetColrTableVersion(colr) == 0) {
return true;
}
*/
return false;
}
void gfxMacFont::AddSizeOfExcludingThis(MallocSizeOf aMallocSizeOf,
FontCacheSizes* aSizes) const {
gfxFont::AddSizeOfExcludingThis(aMallocSizeOf, aSizes);
// mCGFont is shared with the font entry, so not counted here;
}
void gfxMacFont::AddSizeOfIncludingThis(MallocSizeOf aMallocSizeOf,
FontCacheSizes* aSizes) const {
aSizes->mFontInstances += aMallocSizeOf(this);
AddSizeOfExcludingThis(aMallocSizeOf, aSizes);
}