gecko-dev/gfx/2d/ScaledFontMac.cpp
Kartikaya Gupta 8e203673f1 Bug 1463416 - use new WR subpixel positioning API from WR PR 2738. r=Gankro
Patch originally developed on bug 1458921 but needs to land with the WR update.

MozReview-Commit-ID: 82BYyNWBAfn

--HG--
extra : rebase_source : e6bca2f446c019fd41a37c2c28db73bbe1cfc216
2018-05-26 11:09:21 -04:00

616 lines
19 KiB
C++

/* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
/* vim: set ts=8 sts=2 et sw=2 tw=80: */
/* 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 "ScaledFontMac.h"
#include "UnscaledFontMac.h"
#include "mozilla/webrender/WebRenderTypes.h"
#ifdef USE_SKIA
#include "PathSkia.h"
#include "skia/include/core/SkPaint.h"
#include "skia/include/core/SkPath.h"
#include "skia/include/ports/SkTypeface_mac.h"
#endif
#include <vector>
#include <dlfcn.h>
#ifdef MOZ_WIDGET_UIKIT
#include <CoreFoundation/CoreFoundation.h>
#endif
#include "nsCocoaFeatures.h"
#include "mozilla/gfx/Logging.h"
#ifdef MOZ_WIDGET_COCOA
// prototype for private API
extern "C" {
CGPathRef CGFontGetGlyphPath(CGFontRef fontRef, CGAffineTransform *textTransform, int unknown, CGGlyph glyph);
};
#endif
#ifdef USE_CAIRO_SCALED_FONT
#include "cairo-quartz.h"
#endif
namespace mozilla {
namespace gfx {
// Simple helper class to automatically release a CFObject when it goes out
// of scope.
template<class T>
class AutoRelease
{
public:
explicit AutoRelease(T aObject)
: mObject(aObject)
{
}
~AutoRelease()
{
if (mObject) {
CFRelease(mObject);
}
}
operator T()
{
return mObject;
}
T forget()
{
T obj = mObject;
mObject = nullptr;
return obj;
}
private:
T mObject;
};
ScaledFontMac::CTFontDrawGlyphsFuncT* ScaledFontMac::CTFontDrawGlyphsPtr = nullptr;
bool ScaledFontMac::sSymbolLookupDone = false;
// Helper to create a CTFont from a CGFont, copying any variations that were
// set on the original CGFont.
static CTFontRef
CreateCTFontFromCGFontWithVariations(CGFontRef aCGFont, CGFloat aSize,
bool aInstalledFont)
{
// Avoid calling potentially buggy variation APIs on pre-Sierra macOS
// versions (see bug 1331683).
//
// And on HighSierra, CTFontCreateWithGraphicsFont properly carries over
// variation settings from the CGFont to CTFont, so we don't need to do
// the extra work here -- and this seems to avoid Core Text crashiness
// seen in bug 1454094.
//
// However, for installed fonts it seems we DO need to copy the variations
// explicitly even on 10.13, otherwise fonts fail to render (as in bug
// 1455494) when non-default values are used. Fortunately, the crash
// mentioned above occurs with data fonts, not (AFAICT) with system-
// installed fonts.
//
// So we only need to do this "the hard way" on Sierra, and for installed
// fonts on HighSierra+; otherwise, just let the standard CTFont function
// do its thing.
//
// NOTE in case this ever needs further adjustment: there is similar logic
// in four places in the tree (sadly):
// CreateCTFontFromCGFontWithVariations in gfxMacFont.cpp
// CreateCTFontFromCGFontWithVariations in ScaledFontMac.cpp
// CreateCTFontFromCGFontWithVariations in cairo-quartz-font.c
// ctfont_create_exact_copy in SkFontHost_mac.cpp
CTFontRef ctFont;
if (nsCocoaFeatures::OnSierraExactly() ||
(aInstalledFont && nsCocoaFeatures::OnHighSierraOrLater())) {
CFDictionaryRef vars = CGFontCopyVariations(aCGFont);
if (vars) {
CFDictionaryRef varAttr =
CFDictionaryCreate(nullptr,
(const void**)&kCTFontVariationAttribute,
(const void**)&vars, 1,
&kCFTypeDictionaryKeyCallBacks,
&kCFTypeDictionaryValueCallBacks);
CFRelease(vars);
CTFontDescriptorRef varDesc =
CTFontDescriptorCreateWithAttributes(varAttr);
CFRelease(varAttr);
ctFont = CTFontCreateWithGraphicsFont(aCGFont, aSize, nullptr,
varDesc);
CFRelease(varDesc);
} else {
ctFont = CTFontCreateWithGraphicsFont(aCGFont, aSize, nullptr,
nullptr);
}
} else {
ctFont = CTFontCreateWithGraphicsFont(aCGFont, aSize, nullptr,
nullptr);
}
return ctFont;
}
ScaledFontMac::ScaledFontMac(CGFontRef aFont,
const RefPtr<UnscaledFont>& aUnscaledFont,
Float aSize,
bool aOwnsFont,
const Color &aFontSmoothingBackgroundColor,
bool aUseFontSmoothing,
bool aApplySyntheticBold)
: ScaledFontBase(aUnscaledFont, aSize)
, mFont(aFont)
, mFontSmoothingBackgroundColor(aFontSmoothingBackgroundColor)
, mUseFontSmoothing(aUseFontSmoothing)
, mApplySyntheticBold(aApplySyntheticBold)
{
if (!sSymbolLookupDone) {
CTFontDrawGlyphsPtr =
(CTFontDrawGlyphsFuncT*)dlsym(RTLD_DEFAULT, "CTFontDrawGlyphs");
sSymbolLookupDone = true;
}
if (!aOwnsFont) {
// XXX: should we be taking a reference
CGFontRetain(aFont);
}
if (CTFontDrawGlyphsPtr != nullptr) {
// only create mCTFont if we're going to be using the CTFontDrawGlyphs API
auto unscaledMac = static_cast<UnscaledFontMac*>(aUnscaledFont.get());
bool dataFont = unscaledMac->IsDataFont();
mCTFont = CreateCTFontFromCGFontWithVariations(aFont, aSize, !dataFont);
} else {
mCTFont = nullptr;
}
}
ScaledFontMac::~ScaledFontMac()
{
if (mCTFont) {
CFRelease(mCTFont);
}
CGFontRelease(mFont);
}
#ifdef USE_SKIA
SkTypeface* ScaledFontMac::GetSkTypeface()
{
if (!mTypeface) {
if (mCTFont) {
mTypeface = SkCreateTypefaceFromCTFont(mCTFont);
} else {
auto unscaledMac = static_cast<UnscaledFontMac*>(GetUnscaledFont().get());
bool dataFont = unscaledMac->IsDataFont();
CTFontRef fontFace =
CreateCTFontFromCGFontWithVariations(mFont, mSize, !dataFont);
mTypeface = SkCreateTypefaceFromCTFont(fontFace);
CFRelease(fontFace);
}
}
return mTypeface;
}
#endif
// private API here are the public options on OS X
// CTFontCreatePathForGlyph
// ATSUGlyphGetCubicPaths
// we've used this in cairo sucessfully for some time.
// Note: cairo dlsyms it. We could do that but maybe it's
// safe just to use?
already_AddRefed<Path>
ScaledFontMac::GetPathForGlyphs(const GlyphBuffer &aBuffer, const DrawTarget *aTarget)
{
return ScaledFontBase::GetPathForGlyphs(aBuffer, aTarget);
}
uint32_t
CalcTableChecksum(const uint32_t *tableStart, uint32_t length, bool skipChecksumAdjust = false)
{
uint32_t sum = 0L;
const uint32_t *table = tableStart;
const uint32_t *end = table + length / sizeof(uint32_t);
while (table < end) {
if (skipChecksumAdjust && (table - tableStart) == 2) {
table++;
} else {
sum += CFSwapInt32BigToHost(*table++);
}
}
// The length is not 4-byte aligned, but we still must process the remaining bytes.
if (length & 3) {
// Pad with zero before adding to the checksum.
uint32_t last = 0;
memcpy(&last, end, length & 3);
sum += CFSwapInt32BigToHost(last);
}
return sum;
}
struct TableRecord {
uint32_t tag;
uint32_t checkSum;
uint32_t offset;
uint32_t length;
CFDataRef data;
};
int maxPow2LessThan(int a)
{
int x = 1;
int shift = 0;
while ((x<<(shift+1)) < a) {
shift++;
}
return shift;
}
struct writeBuf
{
explicit writeBuf(int size)
{
this->data = new unsigned char [size];
this->offset = 0;
}
~writeBuf() {
delete[] this->data;
}
template <class T>
void writeElement(T a)
{
*reinterpret_cast<T*>(&this->data[this->offset]) = a;
this->offset += sizeof(T);
}
void writeMem(const void *data, unsigned long length)
{
memcpy(&this->data[this->offset], data, length);
this->offset += length;
}
void align()
{
while (this->offset & 3) {
this->data[this->offset] = 0;
this->offset++;
}
}
unsigned char *data;
int offset;
};
bool
UnscaledFontMac::GetFontFileData(FontFileDataOutput aDataCallback, void *aBaton)
{
// We'll reconstruct a TTF font from the tables we can get from the CGFont
CFArrayRef tags = CGFontCopyTableTags(mFont);
CFIndex count = CFArrayGetCount(tags);
TableRecord *records = new TableRecord[count];
uint32_t offset = 0;
offset += sizeof(uint32_t)*3;
offset += sizeof(uint32_t)*4*count;
bool CFF = false;
for (CFIndex i = 0; i<count; i++) {
uint32_t tag = (uint32_t)(uintptr_t)CFArrayGetValueAtIndex(tags, i);
if (tag == 0x43464620) // 'CFF '
CFF = true;
CFDataRef data = CGFontCopyTableForTag(mFont, tag);
records[i].tag = tag;
records[i].offset = offset;
records[i].data = data;
records[i].length = CFDataGetLength(data);
bool skipChecksumAdjust = (tag == 0x68656164); // 'head'
records[i].checkSum = CalcTableChecksum(reinterpret_cast<const uint32_t*>(CFDataGetBytePtr(data)),
records[i].length, skipChecksumAdjust);
offset += records[i].length;
// 32 bit align the tables
offset = (offset + 3) & ~3;
}
CFRelease(tags);
struct writeBuf buf(offset);
// write header/offset table
if (CFF) {
buf.writeElement(CFSwapInt32HostToBig(0x4f54544f));
} else {
buf.writeElement(CFSwapInt32HostToBig(0x00010000));
}
buf.writeElement(CFSwapInt16HostToBig(count));
buf.writeElement(CFSwapInt16HostToBig((1<<maxPow2LessThan(count))*16));
buf.writeElement(CFSwapInt16HostToBig(maxPow2LessThan(count)));
buf.writeElement(CFSwapInt16HostToBig(count*16-((1<<maxPow2LessThan(count))*16)));
// write table record entries
for (CFIndex i = 0; i<count; i++) {
buf.writeElement(CFSwapInt32HostToBig(records[i].tag));
buf.writeElement(CFSwapInt32HostToBig(records[i].checkSum));
buf.writeElement(CFSwapInt32HostToBig(records[i].offset));
buf.writeElement(CFSwapInt32HostToBig(records[i].length));
}
// write tables
int checkSumAdjustmentOffset = 0;
for (CFIndex i = 0; i<count; i++) {
if (records[i].tag == 0x68656164) {
checkSumAdjustmentOffset = buf.offset + 2*4;
}
buf.writeMem(CFDataGetBytePtr(records[i].data), CFDataGetLength(records[i].data));
buf.align();
CFRelease(records[i].data);
}
delete[] records;
// clear the checksumAdjust field before checksumming the whole font
memset(&buf.data[checkSumAdjustmentOffset], 0, sizeof(uint32_t));
uint32_t fontChecksum = CFSwapInt32HostToBig(0xb1b0afba - CalcTableChecksum(reinterpret_cast<const uint32_t*>(buf.data), offset));
// set checkSumAdjust to the computed checksum
memcpy(&buf.data[checkSumAdjustmentOffset], &fontChecksum, sizeof(fontChecksum));
// we always use an index of 0
aDataCallback(buf.data, buf.offset, 0, aBaton);
return true;
}
bool
UnscaledFontMac::GetWRFontDescriptor(WRFontDescriptorOutput aCb, void* aBaton)
{
if (mIsDataFont) {
return false;
}
CFStringRef psname = CGFontCopyPostScriptName(mFont);
if (!psname) {
return false;
}
char buf[256];
const char* cstr = CFStringGetCStringPtr(psname, kCFStringEncodingUTF8);
if (!cstr) {
if (!CFStringGetCString(psname, buf, sizeof(buf), kCFStringEncodingUTF8)) {
return false;
}
cstr = buf;
}
aCb(reinterpret_cast<const uint8_t*>(cstr), strlen(cstr), 0, aBaton);
return true;
}
static void
CollectVariationsFromDictionary(const void* aKey, const void* aValue, void* aContext)
{
auto keyPtr = static_cast<const CFTypeRef>(aKey);
auto valuePtr = static_cast<const CFTypeRef>(aValue);
auto outVariations = static_cast<std::vector<FontVariation>*>(aContext);
if (CFGetTypeID(keyPtr) == CFNumberGetTypeID() &&
CFGetTypeID(valuePtr) == CFNumberGetTypeID()) {
uint64_t t;
double v;
if (CFNumberGetValue(static_cast<CFNumberRef>(keyPtr), kCFNumberSInt64Type, &t) &&
CFNumberGetValue(static_cast<CFNumberRef>(valuePtr), kCFNumberDoubleType, &v)) {
outVariations->push_back(FontVariation{uint32_t(t), float(v)});
}
}
}
static bool
GetVariationsForCTFont(CTFontRef aCTFont, std::vector<FontVariation>* aOutVariations)
{
// Avoid calling potentially buggy variation APIs on pre-Sierra macOS
// versions (see bug 1331683)
if (!nsCocoaFeatures::OnSierraOrLater()) {
return true;
}
if (!aCTFont) {
return true;
}
AutoRelease<CFDictionaryRef> dict(CTFontCopyVariation(aCTFont));
CFIndex count = dict ? CFDictionaryGetCount(dict) : 0;
if (count > 0) {
aOutVariations->reserve(count);
CFDictionaryApplyFunction(dict, CollectVariationsFromDictionary, aOutVariations);
}
return true;
}
bool
ScaledFontMac::GetFontInstanceData(FontInstanceDataOutput aCb, void* aBaton)
{
// Collect any variation settings that were incorporated into the CTFont.
std::vector<FontVariation> variations;
if (!GetVariationsForCTFont(mCTFont, &variations)) {
return false;
}
aCb(nullptr, 0, variations.data(), variations.size(), aBaton);
return true;
}
bool
ScaledFontMac::GetWRFontInstanceOptions(Maybe<wr::FontInstanceOptions>* aOutOptions,
Maybe<wr::FontInstancePlatformOptions>* aOutPlatformOptions,
std::vector<FontVariation>* aOutVariations)
{
GetVariationsForCTFont(mCTFont, aOutVariations);
wr::FontInstanceOptions options;
options.render_mode = wr::FontRenderMode::Subpixel;
options.flags = wr::FontInstanceFlags::SUBPIXEL_POSITION;
if (mUseFontSmoothing) {
options.flags |= wr::FontInstanceFlags::FONT_SMOOTHING;
}
if (mApplySyntheticBold) {
options.flags |= wr::FontInstanceFlags::SYNTHETIC_BOLD;
}
options.bg_color = wr::ToColorU(mFontSmoothingBackgroundColor);
*aOutOptions = Some(options);
return true;
}
static CFDictionaryRef
CreateVariationDictionaryOrNull(CGFontRef aCGFont, uint32_t aVariationCount,
const FontVariation* aVariations)
{
// Avoid calling potentially buggy variation APIs on pre-Sierra macOS
// versions (see bug 1331683)
if (!nsCocoaFeatures::OnSierraOrLater()) {
return nullptr;
}
AutoRelease<CTFontRef>
ctFont(CTFontCreateWithGraphicsFont(aCGFont, 0, nullptr, nullptr));
AutoRelease<CFArrayRef> axes(CTFontCopyVariationAxes(ctFont));
if (!axes) {
return nullptr;
}
CFIndex axisCount = CFArrayGetCount(axes);
AutoRelease<CFMutableDictionaryRef>
dict(CFDictionaryCreateMutable(kCFAllocatorDefault, axisCount,
&kCFTypeDictionaryKeyCallBacks,
&kCFTypeDictionaryValueCallBacks));
// Number of variation settings passed in the aVariations parameter.
// This will typically be a very low value, so we just linear-search them.
bool allDefaultValues = true;
for (CFIndex i = 0; i < axisCount; ++i) {
// We sanity-check the axis info found in the CTFont, and bail out
// (returning null) if it doesn't have the expected types.
CFTypeRef axisInfo = CFArrayGetValueAtIndex(axes, i);
if (CFDictionaryGetTypeID() != CFGetTypeID(axisInfo)) {
return nullptr;
}
CFDictionaryRef axis = static_cast<CFDictionaryRef>(axisInfo);
CFTypeRef axisTag =
CFDictionaryGetValue(axis, kCTFontVariationAxisIdentifierKey);
if (!axisTag || CFGetTypeID(axisTag) != CFNumberGetTypeID()) {
return nullptr;
}
int64_t tagLong;
if (!CFNumberGetValue(static_cast<CFNumberRef>(axisTag),
kCFNumberSInt64Type, &tagLong)) {
return nullptr;
}
CFTypeRef axisName =
CFDictionaryGetValue(axis, kCTFontVariationAxisNameKey);
if (!axisName || CFGetTypeID(axisName) != CFStringGetTypeID()) {
return nullptr;
}
// Clamp axis values to the supported range.
CFTypeRef min = CFDictionaryGetValue(axis, kCTFontVariationAxisMinimumValueKey);
CFTypeRef max = CFDictionaryGetValue(axis, kCTFontVariationAxisMaximumValueKey);
CFTypeRef def = CFDictionaryGetValue(axis, kCTFontVariationAxisDefaultValueKey);
if (!min || CFGetTypeID(min) != CFNumberGetTypeID() ||
!max || CFGetTypeID(max) != CFNumberGetTypeID() ||
!def || CFGetTypeID(def) != CFNumberGetTypeID()) {
return nullptr;
}
double minDouble;
double maxDouble;
double defDouble;
if (!CFNumberGetValue(static_cast<CFNumberRef>(min), kCFNumberDoubleType,
&minDouble) ||
!CFNumberGetValue(static_cast<CFNumberRef>(max), kCFNumberDoubleType,
&maxDouble) ||
!CFNumberGetValue(static_cast<CFNumberRef>(def), kCFNumberDoubleType,
&defDouble)) {
return nullptr;
}
double value = defDouble;
for (uint32_t j = 0; j < aVariationCount; ++j) {
if (aVariations[j].mTag == tagLong) {
value = std::min(std::max<double>(aVariations[j].mValue,
minDouble),
maxDouble);
if (value != defDouble) {
allDefaultValues = false;
}
break;
}
}
AutoRelease<CFNumberRef> valueNumber(CFNumberCreate(kCFAllocatorDefault,
kCFNumberDoubleType,
&value));
CFDictionaryAddValue(dict, axisName, valueNumber);
}
if (allDefaultValues) {
// We didn't actually set any non-default values, so throw away the
// variations dictionary and just use the default rendering.
return nullptr;
}
return dict.forget();
}
CGFontRef
UnscaledFontMac::CreateCGFontWithVariations(CGFontRef aFont,
uint32_t aVariationCount,
const FontVariation* aVariations)
{
MOZ_ASSERT(aVariationCount > 0);
MOZ_ASSERT(aVariations);
AutoRelease<CFDictionaryRef>
varDict(CreateVariationDictionaryOrNull(aFont, aVariationCount, aVariations));
if (!varDict) {
return nullptr;
}
return CGFontCreateCopyWithVariations(aFont, varDict);
}
already_AddRefed<ScaledFont>
UnscaledFontMac::CreateScaledFont(Float aGlyphSize,
const uint8_t* aInstanceData,
uint32_t aInstanceDataLength,
const FontVariation* aVariations,
uint32_t aNumVariations)
{
CGFontRef fontRef = mFont;
if (aNumVariations > 0) {
CGFontRef varFont =
CreateCGFontWithVariations(mFont, aNumVariations, aVariations);
if (varFont) {
fontRef = varFont;
}
}
RefPtr<ScaledFontMac> scaledFont =
new ScaledFontMac(fontRef, this, aGlyphSize, fontRef != mFont);
if (!scaledFont->PopulateCairoScaledFont()) {
gfxWarning() << "Unable to create cairo scaled Mac font.";
return nullptr;
}
return scaledFont.forget();
}
#ifdef USE_CAIRO_SCALED_FONT
cairo_font_face_t*
ScaledFontMac::GetCairoFontFace()
{
MOZ_ASSERT(mFont);
return cairo_quartz_font_face_create_for_cgfont(mFont);
}
#endif
} // namespace gfx
} // namespace mozilla