blob: 92d253f0458e6264117eba9cae8fa7850a3ff8a0 [file] [log] [blame]
/*
* Copyright (C) 2011 The Android Open Source Project
*
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
#define LOG_TAG "TextLayoutCache"
#include <utils/JenkinsHash.h>
#include "TextLayoutCache.h"
#include "TextLayout.h"
#include "SkTypeface_android.h"
#include "HarfBuzzNGFaceSkia.h"
#include <unicode/unistr.h>
#include <unicode/uchar.h>
#include <hb-icu.h>
namespace android {
//--------------------------------------------------------------------------------------------------
ANDROID_SINGLETON_STATIC_INSTANCE(TextLayoutEngine);
//--------------------------------------------------------------------------------------------------
TextLayoutCache::TextLayoutCache(TextLayoutShaper* shaper) :
mShaper(shaper),
mCache(LruCache<TextLayoutCacheKey, sp<TextLayoutValue> >::kUnlimitedCapacity),
mSize(0), mMaxSize(MB(DEFAULT_TEXT_LAYOUT_CACHE_SIZE_IN_MB)),
mCacheHitCount(0), mNanosecondsSaved(0) {
init();
}
TextLayoutCache::~TextLayoutCache() {
mCache.clear();
}
void TextLayoutCache::init() {
mCache.setOnEntryRemovedListener(this);
mDebugLevel = readRtlDebugLevel();
mDebugEnabled = mDebugLevel & kRtlDebugCaches;
ALOGD("Using debug level = %d - Debug Enabled = %d", mDebugLevel, mDebugEnabled);
mCacheStartTime = systemTime(SYSTEM_TIME_MONOTONIC);
if (mDebugEnabled) {
ALOGD("Initialization is done - Start time = %lld", mCacheStartTime);
}
mInitialized = true;
}
/**
* Callbacks
*/
void TextLayoutCache::operator()(TextLayoutCacheKey& text, sp<TextLayoutValue>& desc) {
size_t totalSizeToDelete = text.getSize() + desc->getSize();
mSize -= totalSizeToDelete;
if (mDebugEnabled) {
ALOGD("Cache value %p deleted, size = %d", desc.get(), totalSizeToDelete);
}
}
/*
* Cache clearing
*/
void TextLayoutCache::purgeCaches() {
AutoMutex _l(mLock);
mCache.clear();
mShaper->purgeCaches();
}
/*
* Caching
*/
sp<TextLayoutValue> TextLayoutCache::getValue(const SkPaint* paint,
const jchar* text, jint start, jint count, jint contextCount, jint dirFlags) {
AutoMutex _l(mLock);
nsecs_t startTime = 0;
if (mDebugEnabled) {
startTime = systemTime(SYSTEM_TIME_MONOTONIC);
}
// Create the key
TextLayoutCacheKey key(paint, text, start, count, contextCount, dirFlags);
// Get value from cache if possible
sp<TextLayoutValue> value = mCache.get(key);
// Value not found for the key, we need to add a new value in the cache
if (value == NULL) {
if (mDebugEnabled) {
startTime = systemTime(SYSTEM_TIME_MONOTONIC);
}
value = new TextLayoutValue(contextCount);
// Compute advances and store them
mShaper->computeValues(value.get(), paint,
reinterpret_cast<const UChar*>(key.getText()), start, count,
size_t(contextCount), int(dirFlags));
if (mDebugEnabled) {
value->setElapsedTime(systemTime(SYSTEM_TIME_MONOTONIC) - startTime);
}
// Don't bother to add in the cache if the entry is too big
size_t size = key.getSize() + value->getSize();
if (size <= mMaxSize) {
// Cleanup to make some room if needed
if (mSize + size > mMaxSize) {
if (mDebugEnabled) {
ALOGD("Need to clean some entries for making some room for a new entry");
}
while (mSize + size > mMaxSize) {
// This will call the callback
bool removedOne = mCache.removeOldest();
LOG_ALWAYS_FATAL_IF(!removedOne, "The cache is non-empty but we "
"failed to remove the oldest entry. "
"mSize = %u, size = %u, mMaxSize = %u, mCache.size() = %u",
mSize, size, mMaxSize, mCache.size());
}
}
// Update current cache size
mSize += size;
bool putOne = mCache.put(key, value);
LOG_ALWAYS_FATAL_IF(!putOne, "Failed to put an entry into the cache. "
"This indicates that the cache already has an entry with the "
"same key but it should not since we checked earlier!"
" - start = %d, count = %d, contextCount = %d - Text = '%s'",
start, count, contextCount, String8(key.getText() + start, count).string());
if (mDebugEnabled) {
nsecs_t totalTime = systemTime(SYSTEM_TIME_MONOTONIC) - startTime;
ALOGD("CACHE MISS: Added entry %p "
"with start = %d, count = %d, contextCount = %d, "
"entry size %d bytes, remaining space %d bytes"
" - Compute time %0.6f ms - Put time %0.6f ms - Text = '%s'",
value.get(), start, count, contextCount, size, mMaxSize - mSize,
value->getElapsedTime() * 0.000001f,
(totalTime - value->getElapsedTime()) * 0.000001f,
String8(key.getText() + start, count).string());
}
} else {
if (mDebugEnabled) {
ALOGD("CACHE MISS: Calculated but not storing entry because it is too big "
"with start = %d, count = %d, contextCount = %d, "
"entry size %d bytes, remaining space %d bytes"
" - Compute time %0.6f ms - Text = '%s'",
start, count, contextCount, size, mMaxSize - mSize,
value->getElapsedTime() * 0.000001f,
String8(key.getText() + start, count).string());
}
}
} else {
// This is a cache hit, just log timestamp and user infos
if (mDebugEnabled) {
nsecs_t elapsedTimeThruCacheGet = systemTime(SYSTEM_TIME_MONOTONIC) - startTime;
mNanosecondsSaved += (value->getElapsedTime() - elapsedTimeThruCacheGet);
++mCacheHitCount;
if (value->getElapsedTime() > 0) {
float deltaPercent = 100 * ((value->getElapsedTime() - elapsedTimeThruCacheGet)
/ ((float)value->getElapsedTime()));
ALOGD("CACHE HIT #%d with start = %d, count = %d, contextCount = %d"
"- Compute time %0.6f ms - "
"Cache get time %0.6f ms - Gain in percent: %2.2f - Text = '%s'",
mCacheHitCount, start, count, contextCount,
value->getElapsedTime() * 0.000001f,
elapsedTimeThruCacheGet * 0.000001f,
deltaPercent,
String8(key.getText() + start, count).string());
}
if (mCacheHitCount % DEFAULT_DUMP_STATS_CACHE_HIT_INTERVAL == 0) {
dumpCacheStats();
}
}
}
return value;
}
void TextLayoutCache::dumpCacheStats() {
float remainingPercent = 100 * ((mMaxSize - mSize) / ((float)mMaxSize));
float timeRunningInSec = (systemTime(SYSTEM_TIME_MONOTONIC) - mCacheStartTime) / 1000000000;
size_t cacheSize = mCache.size();
ALOGD("------------------------------------------------");
ALOGD("Cache stats");
ALOGD("------------------------------------------------");
ALOGD("pid : %d", getpid());
ALOGD("running : %.0f seconds", timeRunningInSec);
ALOGD("entries : %d", cacheSize);
ALOGD("max size : %d bytes", mMaxSize);
ALOGD("used : %d bytes according to mSize", mSize);
ALOGD("remaining : %d bytes or %2.2f percent", mMaxSize - mSize, remainingPercent);
ALOGD("hits : %d", mCacheHitCount);
ALOGD("saved : %0.6f ms", mNanosecondsSaved * 0.000001f);
ALOGD("------------------------------------------------");
}
/**
* TextLayoutCacheKey
*/
TextLayoutCacheKey::TextLayoutCacheKey(): start(0), count(0), contextCount(0),
dirFlags(0), typeface(NULL), textSize(0), textSkewX(0), textScaleX(0), flags(0),
hinting(SkPaint::kNo_Hinting) {
paintOpts.setUseFontFallbacks(true);
}
TextLayoutCacheKey::TextLayoutCacheKey(const SkPaint* paint, const UChar* text,
size_t start, size_t count, size_t contextCount, int dirFlags) :
start(start), count(count), contextCount(contextCount),
dirFlags(dirFlags) {
textCopy.setTo(text, contextCount);
typeface = paint->getTypeface();
textSize = paint->getTextSize();
textSkewX = paint->getTextSkewX();
textScaleX = paint->getTextScaleX();
flags = paint->getFlags();
hinting = paint->getHinting();
paintOpts = paint->getPaintOptionsAndroid();
}
TextLayoutCacheKey::TextLayoutCacheKey(const TextLayoutCacheKey& other) :
textCopy(other.textCopy),
start(other.start),
count(other.count),
contextCount(other.contextCount),
dirFlags(other.dirFlags),
typeface(other.typeface),
textSize(other.textSize),
textSkewX(other.textSkewX),
textScaleX(other.textScaleX),
flags(other.flags),
hinting(other.hinting),
paintOpts(other.paintOpts) {
}
int TextLayoutCacheKey::compare(const TextLayoutCacheKey& lhs, const TextLayoutCacheKey& rhs) {
int deltaInt = lhs.start - rhs.start;
if (deltaInt != 0) return (deltaInt);
deltaInt = lhs.count - rhs.count;
if (deltaInt != 0) return (deltaInt);
deltaInt = lhs.contextCount - rhs.contextCount;
if (deltaInt != 0) return (deltaInt);
if (lhs.typeface < rhs.typeface) return -1;
if (lhs.typeface > rhs.typeface) return +1;
if (lhs.textSize < rhs.textSize) return -1;
if (lhs.textSize > rhs.textSize) return +1;
if (lhs.textSkewX < rhs.textSkewX) return -1;
if (lhs.textSkewX > rhs.textSkewX) return +1;
if (lhs.textScaleX < rhs.textScaleX) return -1;
if (lhs.textScaleX > rhs.textScaleX) return +1;
deltaInt = lhs.flags - rhs.flags;
if (deltaInt != 0) return (deltaInt);
deltaInt = lhs.hinting - rhs.hinting;
if (deltaInt != 0) return (deltaInt);
deltaInt = lhs.dirFlags - rhs.dirFlags;
if (deltaInt) return (deltaInt);
if (lhs.paintOpts != rhs.paintOpts)
return memcmp(&lhs.paintOpts, &rhs.paintOpts, sizeof(SkPaintOptionsAndroid));
return memcmp(lhs.getText(), rhs.getText(), lhs.contextCount * sizeof(UChar));
}
size_t TextLayoutCacheKey::getSize() const {
return sizeof(TextLayoutCacheKey) + sizeof(UChar) * contextCount;
}
hash_t TextLayoutCacheKey::hash() const {
uint32_t hash = JenkinsHashMix(0, start);
hash = JenkinsHashMix(hash, count);
/* contextCount not needed because it's included in text, below */
hash = JenkinsHashMix(hash, hash_type(typeface));
hash = JenkinsHashMix(hash, hash_type(textSize));
hash = JenkinsHashMix(hash, hash_type(textSkewX));
hash = JenkinsHashMix(hash, hash_type(textScaleX));
hash = JenkinsHashMix(hash, flags);
hash = JenkinsHashMix(hash, hinting);
hash = JenkinsHashMix(hash, paintOpts.getFontVariant());
// Note: leaving out language is not problematic, as equality comparisons
// are still valid - the only bad thing that could happen is collisions.
hash = JenkinsHashMixShorts(hash, getText(), contextCount);
return JenkinsHashWhiten(hash);
}
/**
* TextLayoutCacheValue
*/
TextLayoutValue::TextLayoutValue(size_t contextCount) :
mTotalAdvance(0), mElapsedTime(0) {
mBounds.setEmpty();
// Give a hint for advances and glyphs vectors size
mAdvances.setCapacity(contextCount);
mGlyphs.setCapacity(contextCount);
mPos.setCapacity(contextCount * 2);
}
size_t TextLayoutValue::getSize() const {
return sizeof(TextLayoutValue) + sizeof(jfloat) * mAdvances.capacity() +
sizeof(jchar) * mGlyphs.capacity() + sizeof(jfloat) * mPos.capacity();
}
void TextLayoutValue::setElapsedTime(uint32_t time) {
mElapsedTime = time;
}
uint32_t TextLayoutValue::getElapsedTime() {
return mElapsedTime;
}
TextLayoutShaper::TextLayoutShaper() {
mBuffer = hb_buffer_create();
}
TextLayoutShaper::~TextLayoutShaper() {
hb_buffer_destroy(mBuffer);
}
void TextLayoutShaper::computeValues(TextLayoutValue* value, const SkPaint* paint,
const UChar* chars, size_t start, size_t count, size_t contextCount, int dirFlags) {
computeValues(paint, chars, start, count, contextCount, dirFlags,
&value->mAdvances, &value->mTotalAdvance, &value->mBounds,
&value->mGlyphs, &value->mPos);
#if DEBUG_ADVANCES
ALOGD("Advances - start = %d, count = %d, contextCount = %d, totalAdvance = %f", start, count,
contextCount, value->mTotalAdvance);
#endif
}
void TextLayoutShaper::computeValues(const SkPaint* paint, const UChar* chars,
size_t start, size_t count, size_t contextCount, int dirFlags,
Vector<jfloat>* const outAdvances, jfloat* outTotalAdvance, SkRect* outBounds,
Vector<jchar>* const outGlyphs, Vector<jfloat>* const outPos) {
*outTotalAdvance = 0;
if (!count) {
return;
}
UBiDiLevel bidiReq = 0;
bool forceLTR = false;
bool forceRTL = false;
switch (dirFlags & kBidi_Mask) {
case kBidi_LTR: bidiReq = 0; break; // no ICU constant, canonical LTR level
case kBidi_RTL: bidiReq = 1; break; // no ICU constant, canonical RTL level
case kBidi_Default_LTR: bidiReq = UBIDI_DEFAULT_LTR; break;
case kBidi_Default_RTL: bidiReq = UBIDI_DEFAULT_RTL; break;
case kBidi_Force_LTR: forceLTR = true; break; // every char is LTR
case kBidi_Force_RTL: forceRTL = true; break; // every char is RTL
}
bool useSingleRun = false;
bool isRTL = forceRTL;
if (forceLTR || forceRTL) {
useSingleRun = true;
} else {
UBiDi* bidi = ubidi_open();
if (bidi) {
UErrorCode status = U_ZERO_ERROR;
#if DEBUG_GLYPHS
ALOGD("******** ComputeValues -- start");
ALOGD(" -- string = '%s'", String8(chars + start, count).string());
ALOGD(" -- start = %d", start);
ALOGD(" -- count = %d", count);
ALOGD(" -- contextCount = %d", contextCount);
ALOGD(" -- bidiReq = %d", bidiReq);
#endif
ubidi_setPara(bidi, chars, contextCount, bidiReq, NULL, &status);
if (U_SUCCESS(status)) {
int paraDir = ubidi_getParaLevel(bidi) & kDirection_Mask; // 0 if ltr, 1 if rtl
ssize_t rc = ubidi_countRuns(bidi, &status);
#if DEBUG_GLYPHS
ALOGD(" -- dirFlags = %d", dirFlags);
ALOGD(" -- paraDir = %d", paraDir);
ALOGD(" -- run-count = %d", int(rc));
#endif
if (U_SUCCESS(status) && rc == 1) {
// Normal case: one run, status is ok
isRTL = (paraDir == 1);
useSingleRun = true;
} else if (!U_SUCCESS(status) || rc < 1) {
ALOGW("Need to force to single run -- string = '%s',"
" status = %d, rc = %d",
String8(chars + start, count).string(), status, int(rc));
isRTL = (paraDir == 1);
useSingleRun = true;
} else {
int32_t end = start + count;
for (size_t i = 0; i < size_t(rc); ++i) {
int32_t startRun = -1;
int32_t lengthRun = -1;
UBiDiDirection runDir = ubidi_getVisualRun(bidi, i, &startRun, &lengthRun);
if (startRun == -1 || lengthRun == -1) {
// Something went wrong when getting the visual run, need to clear
// already computed data before doing a single run pass
ALOGW("Visual run is not valid");
outGlyphs->clear();
outAdvances->clear();
outPos->clear();
*outTotalAdvance = 0;
isRTL = (paraDir == 1);
useSingleRun = true;
break;
}
if (startRun >= end) {
continue;
}
int32_t endRun = startRun + lengthRun;
if (endRun <= int32_t(start)) {
continue;
}
if (startRun < int32_t(start)) {
startRun = int32_t(start);
}
if (endRun > end) {
endRun = end;
}
lengthRun = endRun - startRun;
isRTL = (runDir == UBIDI_RTL);
#if DEBUG_GLYPHS
ALOGD("Processing Bidi Run = %d -- run-start = %d, run-len = %d, isRTL = %d",
i, startRun, lengthRun, isRTL);
#endif
computeRunValues(paint, chars, startRun, lengthRun, contextCount, isRTL,
outAdvances, outTotalAdvance, outBounds, outGlyphs, outPos);
}
}
} else {
ALOGW("Cannot set Para");
useSingleRun = true;
isRTL = (bidiReq = 1) || (bidiReq = UBIDI_DEFAULT_RTL);
}
ubidi_close(bidi);
} else {
ALOGW("Cannot ubidi_open()");
useSingleRun = true;
isRTL = (bidiReq = 1) || (bidiReq = UBIDI_DEFAULT_RTL);
}
}
// Default single run case
if (useSingleRun){
#if DEBUG_GLYPHS
ALOGD("Using a SINGLE BiDi Run "
"-- run-start = %d, run-len = %d, isRTL = %d", start, count, isRTL);
#endif
computeRunValues(paint, chars, start, count, contextCount, isRTL,
outAdvances, outTotalAdvance, outBounds, outGlyphs, outPos);
}
#if DEBUG_GLYPHS
ALOGD(" -- Total returned glyphs-count = %d", outGlyphs->size());
ALOGD("******** ComputeValues -- end");
#endif
}
#define HB_IsHighSurrogate(ucs) \
(((ucs) & 0xfc00) == 0xd800)
#define HB_IsLowSurrogate(ucs) \
(((ucs) & 0xfc00) == 0xdc00)
#ifndef HB_SurrogateToUcs4
#define HB_SurrogateToUcs4_(high, low) \
(((hb_codepoint_t)(high))<<10) + (low) - 0x35fdc00;
#endif
#define HB_InvalidCodePoint ~0u
hb_codepoint_t
utf16_to_code_point(const uint16_t *chars, size_t len, ssize_t *iter) {
const uint16_t v = chars[(*iter)++];
if (HB_IsHighSurrogate(v)) {
// surrogate pair
if (size_t(*iter) >= len) {
// the surrogate is incomplete.
return HB_InvalidCodePoint;
}
const uint16_t v2 = chars[(*iter)++];
if (!HB_IsLowSurrogate(v2)) {
// invalidate surrogate pair.
(*iter)--;
return HB_InvalidCodePoint;
}
return HB_SurrogateToUcs4(v, v2);
}
if (HB_IsLowSurrogate(v)) {
// this isn't a valid code point
return HB_InvalidCodePoint;
}
return v;
}
hb_codepoint_t
utf16_to_code_point_prev(const uint16_t *chars, size_t len, ssize_t *iter) {
const uint16_t v = chars[(*iter)--];
if (HB_IsLowSurrogate(v)) {
// surrogate pair
if (*iter < 0) {
// the surrogate is incomplete.
return HB_InvalidCodePoint;
}
const uint16_t v2 = chars[(*iter)--];
if (!HB_IsHighSurrogate(v2)) {
// invalidate surrogate pair.
(*iter)++;
return HB_InvalidCodePoint;
}
return HB_SurrogateToUcs4(v2, v);
}
if (HB_IsHighSurrogate(v)) {
// this isn't a valid code point
return HB_InvalidCodePoint;
}
return v;
}
struct ScriptRun {
hb_script_t script;
size_t pos;
size_t length;
};
hb_script_t code_point_to_script(hb_codepoint_t codepoint) {
static hb_unicode_funcs_t* u;
if (!u) {
u = hb_icu_get_unicode_funcs();
}
return hb_unicode_script(u, codepoint);
}
bool
hb_utf16_script_run_next(ScriptRun* run, const uint16_t *chars, size_t len, ssize_t *iter) {
if (size_t(*iter) == len)
return false;
run->pos = *iter;
const uint32_t init_cp = utf16_to_code_point(chars, len, iter);
const hb_script_t init_script = code_point_to_script(init_cp);
hb_script_t current_script = init_script;
run->script = init_script;
for (;;) {
if (size_t(*iter) == len)
break;
const ssize_t prev_iter = *iter;
const uint32_t cp = utf16_to_code_point(chars, len, iter);
const hb_script_t script = code_point_to_script(cp);
if (script != current_script) {
/* BEGIN android-changed
The condition was not correct by doing "a == b == constant"
END android-changed */
if (current_script == HB_SCRIPT_INHERITED && init_script == HB_SCRIPT_INHERITED) {
// If we started off as inherited, we take whatever we can find.
run->script = script;
current_script = script;
continue;
} else if (script == HB_SCRIPT_INHERITED) {
continue;
} else {
*iter = prev_iter;
break;
}
}
}
if (run->script == HB_SCRIPT_INHERITED)
run->script = HB_SCRIPT_COMMON;
run->length = *iter - run->pos;
return true;
}
bool
hb_utf16_script_run_prev(ScriptRun* run, const uint16_t *chars, size_t len, ssize_t *iter) {
if (*iter == -1)
return false;
const size_t ending_index = *iter;
const uint32_t init_cp = utf16_to_code_point_prev(chars, len, iter);
const hb_script_t init_script = code_point_to_script(init_cp);
hb_script_t current_script = init_script;
run->script = init_script;
size_t break_iter = *iter;
for (;;) {
if (*iter < 0)
break;
const uint32_t cp = utf16_to_code_point_prev(chars, len, iter);
const hb_script_t script = code_point_to_script(cp);
if (script != current_script) {
if (current_script == HB_SCRIPT_INHERITED && init_script == HB_SCRIPT_INHERITED) {
// If we started off as inherited, we take whatever we can find.
run->script = script;
current_script = script;
// In cases of script1 + inherited + script2, always group the inherited
// with script1.
break_iter = *iter;
continue;
} else if (script == HB_SCRIPT_INHERITED) {
continue;
} else {
*iter = break_iter;
break;
}
} else {
break_iter = *iter;
}
}
if (run->script == HB_SCRIPT_INHERITED)
run->script = HB_SCRIPT_COMMON;
run->pos = *iter + 1;
run->length = ending_index - *iter;
return true;
}
static void logGlyphs(hb_buffer_t* buffer) {
unsigned int numGlyphs;
hb_glyph_info_t* info = hb_buffer_get_glyph_infos(buffer, &numGlyphs);
hb_glyph_position_t* positions = hb_buffer_get_glyph_positions(buffer, NULL);
ALOGD(" -- glyphs count=%d", numGlyphs);
for (size_t i = 0; i < numGlyphs; i++) {
ALOGD(" -- glyph[%d] = %d, cluster = %u, advance = %0.2f, offset.x = %0.2f, offset.y = %0.2f", i,
info[i].codepoint,
info[i].cluster,
HBFixedToFloat(positions[i].x_advance),
HBFixedToFloat(positions[i].x_offset),
HBFixedToFloat(positions[i].y_offset));
}
}
void TextLayoutShaper::computeRunValues(const SkPaint* paint, const UChar* contextChars,
size_t start, size_t count, size_t contextCount, bool isRTL,
Vector<jfloat>* const outAdvances, jfloat* outTotalAdvance, SkRect* outBounds,
Vector<jchar>* const outGlyphs, Vector<jfloat>* const outPos) {
if (!count) {
// We cannot shape an empty run.
return;
}
// To be filled in later
for (size_t i = 0; i < count; i++) {
outAdvances->add(0);
}
// Set the string properties
const UChar* chars = contextChars + start;
// Define shaping paint properties
mShapingPaint.setTextSize(paint->getTextSize());
float skewX = paint->getTextSkewX();
mShapingPaint.setTextSkewX(skewX);
mShapingPaint.setTextScaleX(paint->getTextScaleX());
mShapingPaint.setFlags(paint->getFlags());
mShapingPaint.setHinting(paint->getHinting());
mShapingPaint.setPaintOptionsAndroid(paint->getPaintOptionsAndroid());
// Split the BiDi run into Script runs. Harfbuzz will populate the pos, length and script
// into the shaperItem
ssize_t indexFontRun = isRTL ? count - 1 : 0;
jfloat totalAdvance = *outTotalAdvance;
ScriptRun run; // relative to chars
while ((isRTL) ?
hb_utf16_script_run_prev(&run, chars, count, &indexFontRun):
hb_utf16_script_run_next(&run, chars, count, &indexFontRun)) {
#if DEBUG_GLYPHS
ALOGD("-------- Start of Script Run --------");
ALOGD("Shaping Script Run with");
ALOGD(" -- isRTL = %d", isRTL);
ALOGD(" -- HB script = %c%c%c%c", HB_UNTAG(run.script));
ALOGD(" -- run.pos = %d", int(run.pos));
ALOGD(" -- run.length = %d", int(run.length));
ALOGD(" -- run = '%s'", String8(chars + run.pos, run.length).string());
ALOGD(" -- string = '%s'", String8(chars, count).string());
#endif
hb_buffer_reset(mBuffer);
// Note: if we want to set unicode functions, etc., this is the place.
hb_buffer_set_direction(mBuffer, isRTL ? HB_DIRECTION_RTL : HB_DIRECTION_LTR);
hb_buffer_set_script(mBuffer, run.script);
SkString langString = paint->getPaintOptionsAndroid().getLanguage().getTag();
hb_buffer_set_language(mBuffer, hb_language_from_string(langString.c_str(), -1));
hb_buffer_add_utf16(mBuffer, contextChars, contextCount, start + run.pos, run.length);
// Initialize Harfbuzz Shaper and get the base glyph count for offsetting the glyphIDs
// and shape the Font run
size_t glyphBaseCount = shapeFontRun(paint);
unsigned int numGlyphs;
hb_glyph_info_t* info = hb_buffer_get_glyph_infos(mBuffer, &numGlyphs);
hb_glyph_position_t* positions = hb_buffer_get_glyph_positions(mBuffer, NULL);
#if DEBUG_GLYPHS
ALOGD("Got from Harfbuzz");
ALOGD(" -- glyphBaseCount = %d", glyphBaseCount);
ALOGD(" -- num_glyph = %d", numGlyphs);
ALOGD(" -- isDevKernText = %d", paint->isDevKernText());
ALOGD(" -- initial totalAdvance = %f", totalAdvance);
logGlyphs(mBuffer);
#endif
for (size_t i = 0; i < numGlyphs; i++) {
size_t cluster = info[i].cluster - start;
float xAdvance = HBFixedToFloat(positions[i].x_advance);
outAdvances->replaceAt(outAdvances->itemAt(cluster) + xAdvance, cluster);
jchar glyphId = info[i].codepoint + glyphBaseCount;
outGlyphs->add(glyphId);
float xo = HBFixedToFloat(positions[i].x_offset);
float yo = -HBFixedToFloat(positions[i].y_offset);
float xpos = totalAdvance + xo + yo * skewX;
float ypos = yo;
outPos->add(xpos);
outPos->add(ypos);
totalAdvance += xAdvance;
// TODO: consider using glyph cache
const SkGlyph& metrics = mShapingPaint.getGlyphMetrics(glyphId, NULL);
outBounds->join(xpos + metrics.fLeft, ypos + metrics.fTop,
xpos + metrics.fLeft + metrics.fWidth, ypos + metrics.fTop + metrics.fHeight);
}
}
*outTotalAdvance = totalAdvance;
#if DEBUG_GLYPHS
ALOGD(" -- final totalAdvance = %f", totalAdvance);
ALOGD("-------- End of Script Run --------");
#endif
}
/**
* Return the first typeface in the logical change, starting with this typeface,
* that contains the specified unichar, or NULL if none is found.
*/
SkTypeface* TextLayoutShaper::typefaceForScript(const SkPaint* paint, SkTypeface* typeface,
hb_script_t script) {
SkTypeface::Style currentStyle = SkTypeface::kNormal;
if (typeface) {
currentStyle = typeface->style();
}
typeface = SkCreateTypefaceForScriptNG(script, currentStyle);
#if DEBUG_GLYPHS
ALOGD("Using Harfbuzz Script %c%c%c%c, Style %d", HB_UNTAG(script), currentStyle);
#endif
return typeface;
}
bool TextLayoutShaper::isComplexScript(hb_script_t script) {
switch (script) {
case HB_SCRIPT_COMMON:
case HB_SCRIPT_GREEK:
case HB_SCRIPT_CYRILLIC:
case HB_SCRIPT_HANGUL:
case HB_SCRIPT_INHERITED:
case HB_SCRIPT_HAN:
case HB_SCRIPT_KATAKANA:
case HB_SCRIPT_HIRAGANA:
return false;
default:
return true;
}
}
size_t TextLayoutShaper::shapeFontRun(const SkPaint* paint) {
// Update Harfbuzz Shaper
SkTypeface* typeface = paint->getTypeface();
// Get the glyphs base count for offsetting the glyphIDs returned by Harfbuzz
// This is needed as the Typeface used for shaping can be not the default one
// when we are shaping any script that needs to use a fallback Font.
// If we are a "common" script we dont need to shift
size_t baseGlyphCount = 0;
hb_codepoint_t firstUnichar = 0;
if (isComplexScript(hb_buffer_get_script(mBuffer))) {
unsigned int numGlyphs;
hb_glyph_info_t* info = hb_buffer_get_glyph_infos(mBuffer, &numGlyphs);
for (size_t i = 0; i < numGlyphs; i++) {
firstUnichar = info[i].codepoint;
if (firstUnichar != ' ') {
break;
}
}
baseGlyphCount = paint->getBaseGlyphCount(firstUnichar);
}
SkTypeface* scriptTypeface = NULL;
if (baseGlyphCount != 0) {
scriptTypeface = typefaceForScript(paint, typeface,
hb_buffer_get_script(mBuffer));
#if DEBUG_GLYPHS
ALOGD("Using Default Typeface for script %c%c%c%c",
HB_UNTAG(hb_buffer_get_script(mBuffer)));
#endif
}
if (scriptTypeface) {
typeface = scriptTypeface;
} else {
baseGlyphCount = 0;
if (typeface) {
SkSafeRef(typeface);
} else {
typeface = SkTypeface::CreateFromName(NULL, SkTypeface::kNormal);
#if DEBUG_GLYPHS
ALOGD("Using Default Typeface (normal style)");
#endif
}
}
mShapingPaint.setTypeface(typeface);
hb_face_t* face = referenceCachedHBFace(typeface);
float sizeY = paint->getTextSize();
float sizeX = sizeY * paint->getTextScaleX();
hb_font_t* font = createFont(face, &mShapingPaint, sizeX, sizeY);
hb_face_destroy(face);
#if DEBUG_GLYPHS
ALOGD("Run typeface = %p, uniqueID = %d, face = %p",
typeface, typeface->uniqueID(), face);
#endif
SkSafeUnref(typeface);
hb_shape(font, mBuffer, NULL, 0);
hb_font_destroy(font);
mShapingPaint.setTypeface(paint->getTypeface());
return baseGlyphCount;
}
hb_face_t* TextLayoutShaper::referenceCachedHBFace(SkTypeface* typeface) {
SkFontID fontId = typeface->uniqueID();
ssize_t index = mCachedHBFaces.indexOfKey(fontId);
if (index >= 0) {
return hb_face_reference(mCachedHBFaces.valueAt(index));
}
// TODO: destroy function
hb_face_t* face = hb_face_create_for_tables(harfbuzzSkiaReferenceTable, typeface, NULL);
#if DEBUG_GLYPHS
ALOGD("Created HB_NewFace %p from paint typeface = %p", face, typeface);
#endif
mCachedHBFaces.add(fontId, face);
return hb_face_reference(face);
}
void TextLayoutShaper::purgeCaches() {
size_t cacheSize = mCachedHBFaces.size();
for (size_t i = 0; i < cacheSize; i++) {
hb_face_destroy(mCachedHBFaces.valueAt(i));
}
mCachedHBFaces.clear();
}
TextLayoutEngine::TextLayoutEngine() {
mShaper = new TextLayoutShaper();
#if USE_TEXT_LAYOUT_CACHE
mTextLayoutCache = new TextLayoutCache(mShaper);
#else
mTextLayoutCache = NULL;
#endif
}
TextLayoutEngine::~TextLayoutEngine() {
delete mTextLayoutCache;
delete mShaper;
}
sp<TextLayoutValue> TextLayoutEngine::getValue(const SkPaint* paint, const jchar* text,
jint start, jint count, jint contextCount, jint dirFlags) {
sp<TextLayoutValue> value;
#if USE_TEXT_LAYOUT_CACHE
value = mTextLayoutCache->getValue(paint, text, start, count,
contextCount, dirFlags);
if (value == NULL) {
ALOGE("Cannot get TextLayoutCache value for text = '%s'",
String8(text + start, count).string());
}
#else
value = new TextLayoutValue(count);
mShaper->computeValues(value.get(), paint,
reinterpret_cast<const UChar*>(text), start, count, contextCount, dirFlags);
#endif
return value;
}
void TextLayoutEngine::purgeCaches() {
#if USE_TEXT_LAYOUT_CACHE
mTextLayoutCache->purgeCaches();
#if DEBUG_GLYPHS
ALOGD("Purged TextLayoutEngine caches");
#endif
#endif
}
} // namespace android