blob: ac07a3daf1ca333cf85115483d58cc8364bcf68c [file] [log] [blame]
/*
* Copyright 2018 Google Inc.
*
* Use of this source code is governed by a BSD-style license that can be
* found in the LICENSE file.
*/
#include "include/core/SkFont.h"
#include "include/core/SkFontMetrics.h"
#include "include/core/SkFontMgr.h"
#include "include/core/SkFontStyle.h"
#include "include/core/SkString.h"
#include "include/core/SkTypeface.h"
#include "include/private/SkTFitsIn.h"
#include "modules/skshaper/include/SkShaper.h"
#ifdef SK_UNICODE_AVAILABLE
#include "modules/skshaper/src/SkUnicode.h"
#endif
#include "src/core/SkTextBlobPriv.h"
#include "src/utils/SkUTF.h"
#include <limits.h>
#include <string.h>
#include <locale>
#include <string>
#include <utility>
std::unique_ptr<SkShaper> SkShaper::Make(sk_sp<SkFontMgr> fontmgr) {
#ifdef SK_SHAPER_HARFBUZZ_AVAILABLE
std::unique_ptr<SkShaper> shaper = SkShaper::MakeShaperDrivenWrapper(std::move(fontmgr));
if (shaper) {
return shaper;
}
#endif
return SkShaper::MakePrimitive();
}
void SkShaper::PurgeCaches() {
#ifdef SK_SHAPER_HARFBUZZ_AVAILABLE
PurgeHarfBuzzCache();
#endif
}
std::unique_ptr<SkShaper::BiDiRunIterator>
SkShaper::MakeBiDiRunIterator(const char* utf8, size_t utf8Bytes, uint8_t bidiLevel) {
#ifdef SK_UNICODE_AVAILABLE
auto unicode = SkUnicode::Make();
if (!unicode) {
return nullptr;
}
std::unique_ptr<SkShaper::BiDiRunIterator> bidi =
SkShaper::MakeSkUnicodeBidiRunIterator(unicode.get(),
utf8,
utf8Bytes,
bidiLevel);
if (bidi) {
return bidi;
}
#endif
return std::make_unique<SkShaper::TrivialBiDiRunIterator>(bidiLevel, utf8Bytes);
}
std::unique_ptr<SkShaper::ScriptRunIterator>
SkShaper::MakeScriptRunIterator(const char* utf8, size_t utf8Bytes, SkFourByteTag scriptTag) {
#if defined(SK_SHAPER_HARFBUZZ_AVAILABLE) && defined(SK_UNICODE_AVAILABLE)
auto unicode = SkUnicode::Make();
if (!unicode) {
return nullptr;
}
std::unique_ptr<SkShaper::ScriptRunIterator> script =
SkShaper::MakeSkUnicodeHbScriptRunIterator(unicode.get(), utf8, utf8Bytes);
if (script) {
return script;
}
#endif
return std::make_unique<SkShaper::TrivialScriptRunIterator>(scriptTag, utf8Bytes);
}
SkShaper::SkShaper() {}
SkShaper::~SkShaper() {}
/** Replaces invalid utf-8 sequences with REPLACEMENT CHARACTER U+FFFD. */
static inline SkUnichar utf8_next(const char** ptr, const char* end) {
SkUnichar val = SkUTF::NextUTF8(ptr, end);
return val < 0 ? 0xFFFD : val;
}
class FontMgrRunIterator final : public SkShaper::FontRunIterator {
public:
FontMgrRunIterator(const char* utf8, size_t utf8Bytes,
const SkFont& font, sk_sp<SkFontMgr> fallbackMgr,
const char* requestName, SkFontStyle requestStyle,
const SkShaper::LanguageRunIterator* lang)
: fCurrent(utf8), fBegin(utf8), fEnd(fCurrent + utf8Bytes)
, fFallbackMgr(std::move(fallbackMgr))
, fFont(font)
, fFallbackFont(fFont)
, fCurrentFont(nullptr)
, fRequestName(requestName)
, fRequestStyle(requestStyle)
, fLanguage(lang)
{
fFont.setTypeface(font.refTypefaceOrDefault());
fFallbackFont.setTypeface(nullptr);
}
FontMgrRunIterator(const char* utf8, size_t utf8Bytes,
const SkFont& font, sk_sp<SkFontMgr> fallbackMgr)
: FontMgrRunIterator(utf8, utf8Bytes, font, std::move(fallbackMgr),
nullptr, font.refTypefaceOrDefault()->fontStyle(), nullptr)
{}
void consume() override {
SkASSERT(fCurrent < fEnd);
SkASSERT(!fLanguage || this->endOfCurrentRun() <= fLanguage->endOfCurrentRun());
SkUnichar u = utf8_next(&fCurrent, fEnd);
// If the starting typeface can handle this character, use it.
if (fFont.unicharToGlyph(u)) {
fCurrentFont = &fFont;
// If the current fallback can handle this character, use it.
} else if (fFallbackFont.getTypeface() && fFallbackFont.unicharToGlyph(u)) {
fCurrentFont = &fFallbackFont;
// If not, try to find a fallback typeface
} else {
const char* language = fLanguage ? fLanguage->currentLanguage() : nullptr;
int languageCount = fLanguage ? 1 : 0;
sk_sp<SkTypeface> candidate(fFallbackMgr->matchFamilyStyleCharacter(
fRequestName, fRequestStyle, &language, languageCount, u));
if (candidate) {
fFallbackFont.setTypeface(std::move(candidate));
fCurrentFont = &fFallbackFont;
} else {
fCurrentFont = &fFont;
}
}
while (fCurrent < fEnd) {
const char* prev = fCurrent;
u = utf8_next(&fCurrent, fEnd);
// End run if not using initial typeface and initial typeface has this character.
if (fCurrentFont->getTypeface() != fFont.getTypeface() && fFont.unicharToGlyph(u)) {
fCurrent = prev;
return;
}
// End run if current typeface does not have this character and some other font does.
if (!fCurrentFont->unicharToGlyph(u)) {
const char* language = fLanguage ? fLanguage->currentLanguage() : nullptr;
int languageCount = fLanguage ? 1 : 0;
sk_sp<SkTypeface> candidate(fFallbackMgr->matchFamilyStyleCharacter(
fRequestName, fRequestStyle, &language, languageCount, u));
if (candidate) {
fCurrent = prev;
return;
}
}
}
}
size_t endOfCurrentRun() const override {
return fCurrent - fBegin;
}
bool atEnd() const override {
return fCurrent == fEnd;
}
const SkFont& currentFont() const override {
return *fCurrentFont;
}
private:
char const * fCurrent;
char const * const fBegin;
char const * const fEnd;
sk_sp<SkFontMgr> const fFallbackMgr;
SkFont fFont;
SkFont fFallbackFont;
SkFont* fCurrentFont;
char const * const fRequestName;
SkFontStyle const fRequestStyle;
SkShaper::LanguageRunIterator const * const fLanguage;
};
std::unique_ptr<SkShaper::FontRunIterator>
SkShaper::MakeFontMgrRunIterator(const char* utf8, size_t utf8Bytes,
const SkFont& font, sk_sp<SkFontMgr> fallback)
{
return std::make_unique<FontMgrRunIterator>(utf8, utf8Bytes, font, std::move(fallback));
}
std::unique_ptr<SkShaper::FontRunIterator>
SkShaper::MakeFontMgrRunIterator(const char* utf8, size_t utf8Bytes, const SkFont& font,
sk_sp<SkFontMgr> fallback,
const char* requestName, SkFontStyle requestStyle,
const SkShaper::LanguageRunIterator* language)
{
return std::make_unique<FontMgrRunIterator>(utf8, utf8Bytes, font, std::move(fallback),
requestName, requestStyle, language);
}
std::unique_ptr<SkShaper::LanguageRunIterator>
SkShaper::MakeStdLanguageRunIterator(const char* utf8, size_t utf8Bytes) {
return std::make_unique<TrivialLanguageRunIterator>(std::locale().name().c_str(), utf8Bytes);
}
void SkTextBlobBuilderRunHandler::beginLine() {
fCurrentPosition = fOffset;
fMaxRunAscent = 0;
fMaxRunDescent = 0;
fMaxRunLeading = 0;
}
void SkTextBlobBuilderRunHandler::runInfo(const RunInfo& info) {
SkFontMetrics metrics;
info.fFont.getMetrics(&metrics);
fMaxRunAscent = std::min(fMaxRunAscent, metrics.fAscent);
fMaxRunDescent = std::max(fMaxRunDescent, metrics.fDescent);
fMaxRunLeading = std::max(fMaxRunLeading, metrics.fLeading);
}
void SkTextBlobBuilderRunHandler::commitRunInfo() {
fCurrentPosition.fY -= fMaxRunAscent;
}
SkShaper::RunHandler::Buffer SkTextBlobBuilderRunHandler::runBuffer(const RunInfo& info) {
int glyphCount = SkTFitsIn<int>(info.glyphCount) ? info.glyphCount : INT_MAX;
int utf8RangeSize = SkTFitsIn<int>(info.utf8Range.size()) ? info.utf8Range.size() : INT_MAX;
const auto& runBuffer = fBuilder.allocRunTextPos(info.fFont, glyphCount, utf8RangeSize);
if (runBuffer.utf8text && fUtf8Text) {
memcpy(runBuffer.utf8text, fUtf8Text + info.utf8Range.begin(), utf8RangeSize);
}
fClusters = runBuffer.clusters;
fGlyphCount = glyphCount;
fClusterOffset = info.utf8Range.begin();
return { runBuffer.glyphs,
runBuffer.points(),
nullptr,
runBuffer.clusters,
fCurrentPosition };
}
void SkTextBlobBuilderRunHandler::commitRunBuffer(const RunInfo& info) {
SkASSERT(0 <= fClusterOffset);
for (int i = 0; i < fGlyphCount; ++i) {
SkASSERT(fClusters[i] >= (unsigned)fClusterOffset);
fClusters[i] -= fClusterOffset;
}
fCurrentPosition += info.fAdvance;
}
void SkTextBlobBuilderRunHandler::commitLine() {
fOffset += { 0, fMaxRunDescent + fMaxRunLeading - fMaxRunAscent };
}
sk_sp<SkTextBlob> SkTextBlobBuilderRunHandler::makeBlob() {
return fBuilder.make();
}