gecko-dev/gfx/thebes/gfxMacFont.cpp
Jeremy Chen c0c0bf1903 Bug 1293210 - get cap height from platform APIs for non-sfnt fonts on Mac. r=jfkthame
MozReview-Commit-ID: IiHQQoIvQ3f

--HG--
extra : rebase_source : bc585b776f1712333fc841df66700771d6d2af87
2016-08-18 17:43:54 +08:00

476 lines
16 KiB
C++

/* -*- 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 "gfxMacFont.h"
#include "mozilla/MemoryReporting.h"
#include "mozilla/Sprintf.h"
#include "gfxCoreTextShaper.h"
#include <algorithm>
#include "gfxPlatformMac.h"
#include "gfxContext.h"
#include "gfxFontUtils.h"
#include "gfxMacPlatformFontList.h"
#include "gfxFontConstants.h"
#include "gfxTextRun.h"
#include "cairo-quartz.h"
using namespace mozilla;
using namespace mozilla::gfx;
gfxMacFont::gfxMacFont(MacOSFontEntry *aFontEntry, const gfxFontStyle *aFontStyle,
bool aNeedsBold)
: gfxFont(aFontEntry, aFontStyle),
mCGFont(nullptr),
mCTFont(nullptr),
mFontFace(nullptr)
{
mApplySyntheticBold = aNeedsBold;
mCGFont = aFontEntry->GetFontRef();
if (!mCGFont) {
mIsValid = false;
return;
}
// InitMetrics will handle the sizeAdjust factor and set mAdjustedSize
InitMetrics();
if (!mIsValid) {
return;
}
mFontFace = cairo_quartz_font_face_create_for_cgfont(mCGFont);
cairo_status_t cairoerr = cairo_font_face_status(mFontFace);
if (cairoerr != CAIRO_STATUS_SUCCESS) {
mIsValid = false;
#ifdef DEBUG
char warnBuf[1024];
SprintfLiteral(warnBuf,
"Failed to create Cairo font face: %s status: %d",
NS_ConvertUTF16toUTF8(GetName()).get(), cairoerr);
NS_WARNING(warnBuf);
#endif
return;
}
cairo_matrix_t sizeMatrix, ctm;
cairo_matrix_init_identity(&ctm);
cairo_matrix_init_scale(&sizeMatrix, mAdjustedSize, mAdjustedSize);
// synthetic oblique by skewing via the font matrix
bool needsOblique = mFontEntry != nullptr &&
mFontEntry->IsUpright() &&
mStyle.style != NS_FONT_STYLE_NORMAL &&
mStyle.allowSyntheticStyle;
if (needsOblique) {
cairo_matrix_t style;
cairo_matrix_init(&style,
1, //xx
0, //yx
-1 * OBLIQUE_SKEW_FACTOR, //xy
1, //yy
0, //x0
0); //y0
cairo_matrix_multiply(&sizeMatrix, &sizeMatrix, &style);
}
cairo_font_options_t *fontOptions = cairo_font_options_create();
// turn off font anti-aliasing based on user pref setting
if (mAdjustedSize <=
(gfxFloat)gfxPlatformMac::GetPlatform()->GetAntiAliasingThreshold()) {
cairo_font_options_set_antialias(fontOptions, CAIRO_ANTIALIAS_NONE);
mAntialiasOption = kAntialiasNone;
} else if (mStyle.useGrayscaleAntialiasing) {
cairo_font_options_set_antialias(fontOptions, CAIRO_ANTIALIAS_GRAY);
mAntialiasOption = kAntialiasGrayscale;
}
mScaledFont = cairo_scaled_font_create(mFontFace, &sizeMatrix, &ctm,
fontOptions);
cairo_font_options_destroy(fontOptions);
cairoerr = cairo_scaled_font_status(mScaledFont);
if (cairoerr != CAIRO_STATUS_SUCCESS) {
mIsValid = false;
#ifdef DEBUG
char warnBuf[1024];
SprintfLiteral(warnBuf, "Failed to create scaled font: %s status: %d",
NS_ConvertUTF16toUTF8(GetName()).get(), cairoerr);
NS_WARNING(warnBuf);
#endif
}
}
gfxMacFont::~gfxMacFont()
{
if (mCTFont) {
::CFRelease(mCTFont);
}
if (mScaledFont) {
cairo_scaled_font_destroy(mScaledFont);
}
if (mFontFace) {
cairo_font_face_destroy(mFontFace);
}
}
bool
gfxMacFont::ShapeText(DrawTarget *aDrawTarget,
const char16_t *aText,
uint32_t aOffset,
uint32_t aLength,
Script aScript,
bool aVertical,
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.
if (static_cast<MacOSFontEntry*>(GetFontEntry())->RequiresAATLayout() &&
!aVertical) {
if (!mCoreTextShaper) {
mCoreTextShaper = MakeUnique<gfxCoreTextShaper>(this);
}
if (mCoreTextShaper->ShapeText(aDrawTarget, aText, aOffset, aLength,
aScript, aVertical, aShapedText)) {
PostShapingFixup(aDrawTarget, aText, aOffset,
aLength, aVertical, aShapedText);
return true;
}
}
return gfxFont::ShapeText(aDrawTarget, aText, aOffset, aLength, aScript,
aVertical, aShapedText);
}
bool
gfxMacFont::SetupCairoFont(DrawTarget* aDrawTarget)
{
if (cairo_scaled_font_status(mScaledFont) != 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(gfxFont::RefCairo(aDrawTarget), mScaledFont);
return true;
}
gfxFont::RunMetrics
gfxMacFont::Measure(const gfxTextRun *aTextRun,
uint32_t aStart, uint32_t aEnd,
BoundingBoxType aBoundingBoxType,
DrawTarget *aRefDrawTarget,
Spacing *aSpacing,
uint16_t 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
// if possible (bug 574368) and because CGFontGetUnitsPerEm does not
// 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
// get glyph advances for HarfBuzz, see bug 580863)
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;
}
::CFRelease(headData);
}
if (!upem) {
upem = ::CGFontGetUnitsPerEm(mCGFont);
}
if (upem < 16 || upem > 16384) {
// See http://www.microsoft.com/typography/otspec/head.htm
#ifdef DEBUG
char warnBuf[1024];
SprintfLiteral(warnBuf,
"Bad font metrics for: %s (invalid unitsPerEm value)",
NS_ConvertUTF16toUTF8(mFontEntry->Name()).get());
NS_WARNING(warnBuf);
#endif
return;
}
mAdjustedSize = std::max(mStyle.size, 1.0);
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
// the head table of the font (see bug 580863)
gfxFloat cgConvFactor;
if (static_cast<MacOSFontEntry*>(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;
}
if (mStyle.sizeAdjust > 0.0 && mStyle.size > 0.0 &&
mMetrics.xHeight > 0.0) {
// apply font-size-adjust, and recalculate metrics
gfxFloat aspect = mMetrics.xHeight / mStyle.size;
mAdjustedSize = mStyle.GetAdjustedSize(aspect);
mFUnitsConvFactor = mAdjustedSize / upem;
if (static_cast<MacOSFontEntry*>(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;
}
if (mMetrics.xHeight == 0.0) {
mMetrics.xHeight = ::CGFontGetXHeight(mCGFont) * cgConvFactor;
}
}
// 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
CFDataRef cmap =
::CGFontCopyTableForTag(mCGFont, TRUETYPE_TAG('c','m','a','p'));
uint32_t glyphID;
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;
}
}
if (IsSyntheticBold()) {
mMetrics.aveCharWidth += GetSyntheticBoldOffset();
mMetrics.maxAdvance += GetSyntheticBoldOffset();
}
mMetrics.spaceWidth = GetCharWidth(cmap, ' ', &glyphID, cgConvFactor);
if (glyphID == 0) {
// no space glyph?!
mMetrics.spaceWidth = mMetrics.aveCharWidth;
}
mSpaceGlyph = glyphID;
mMetrics.zeroOrAveCharWidth = GetCharWidth(cmap, '0', &glyphID,
cgConvFactor);
if (glyphID == 0) {
mMetrics.zeroOrAveCharWidth = mMetrics.aveCharWidth;
}
if (cmap) {
::CFRelease(cmap);
}
CalculateDerivedMetrics(mMetrics);
SanitizeMetrics(&mMetrics, mFontEntry->mIsBadUnderlineFont);
#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(DrawTarget& aDrawTarget, uint16_t aGID)
{
if (!mCTFont) {
mCTFont = ::CTFontCreateWithGraphicsFont(mCGFont, mAdjustedSize,
nullptr, nullptr);
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, kCTFontDefaultOrientation, &aGID,
&advance, 1);
return advance.width * 0x10000;
}
// 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()
{
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);
::CFRelease(ctFont);
mIsValid = true;
}
already_AddRefed<ScaledFont>
gfxMacFont::GetScaledFont(DrawTarget *aTarget)
{
if (!mAzureScaledFont) {
NativeFont nativeFont;
nativeFont.mType = NativeFontType::MAC_FONT_FACE;
nativeFont.mFont = GetCGFontRef();
mAzureScaledFont = mozilla::gfx::Factory::CreateScaledFontWithCairo(nativeFont, GetAdjustedSize(), mScaledFont);
}
RefPtr<ScaledFont> scaledFont(mAzureScaledFont);
return scaledFont.forget();
}
already_AddRefed<mozilla::gfx::GlyphRenderingOptions>
gfxMacFont::GetGlyphRenderingOptions(const TextRunDrawParams* aRunParams)
{
if (aRunParams) {
return mozilla::gfx::Factory::CreateCGGlyphRenderingOptions(aRunParams->fontSmoothingBGColor);
}
return nullptr;
}
void
gfxMacFont::AddSizeOfExcludingThis(MallocSizeOf aMallocSizeOf,
FontCacheSizes* aSizes) const
{
gfxFont::AddSizeOfExcludingThis(aMallocSizeOf, aSizes);
// mCGFont is shared with the font entry, so not counted here;
// and we don't have APIs to measure the cairo mFontFace object
}
void
gfxMacFont::AddSizeOfIncludingThis(MallocSizeOf aMallocSizeOf,
FontCacheSizes* aSizes) const
{
aSizes->mFontInstances += aMallocSizeOf(this);
AddSizeOfExcludingThis(aMallocSizeOf, aSizes);
}