blob: 4151a4bcac56df60329a68060dced3b9d9f3919e [file] [log] [blame]
/*
* Copyright (C) 1999 Lars Knoll (knoll@kde.org)
* (C) 1999 Antti Koivisto (koivisto@kde.org)
* (C) 2000 Dirk Mueller (mueller@kde.org)
* Copyright (C) 2003, 2006, 2010, 2011 Apple Inc. All rights reserved.
*
* This library is free software; you can redistribute it and/or
* modify it under the terms of the GNU Library General Public
* License as published by the Free Software Foundation; either
* version 2 of the License, or (at your option) any later version.
*
* This library is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
* Library General Public License for more details.
*
* You should have received a copy of the GNU Library General Public License
* along with this library; see the file COPYING.LIB. If not, write to
* the Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor,
* Boston, MA 02110-1301, USA.
*
*/
#include "config.h"
#include "platform/fonts/Font.h"
#include "platform/LayoutUnit.h"
#include "platform/fonts/Character.h"
#include "platform/fonts/FontCache.h"
#include "platform/fonts/FontFallbackList.h"
#include "platform/fonts/FontPlatformFeatures.h"
#include "platform/fonts/GlyphBuffer.h"
#include "platform/fonts/GlyphPageTreeNode.h"
#include "platform/fonts/SimpleFontData.h"
#include "platform/fonts/WidthIterator.h"
#include "platform/geometry/FloatRect.h"
#include "platform/text/TextRun.h"
#include "wtf/MainThread.h"
#include "wtf/StdLibExtras.h"
#include "wtf/unicode/CharacterNames.h"
#include "wtf/unicode/Unicode.h"
using namespace WTF;
using namespace Unicode;
using namespace std;
namespace blink {
CodePath Font::s_codePath = AutoPath;
// ============================================================================================
// Font Implementation (Cross-Platform Portion)
// ============================================================================================
Font::Font()
{
}
Font::Font(const FontDescription& fd)
: m_fontDescription(fd)
{
}
Font::Font(const Font& other)
: m_fontDescription(other.m_fontDescription)
, m_fontFallbackList(other.m_fontFallbackList)
{
}
Font& Font::operator=(const Font& other)
{
m_fontDescription = other.m_fontDescription;
m_fontFallbackList = other.m_fontFallbackList;
return *this;
}
bool Font::operator==(const Font& other) const
{
// Our FontData don't have to be checked, since checking the font description will be fine.
// FIXME: This does not work if the font was made with the FontPlatformData constructor.
if (loadingCustomFonts() || other.loadingCustomFonts())
return false;
FontSelector* first = m_fontFallbackList ? m_fontFallbackList->fontSelector() : 0;
FontSelector* second = other.m_fontFallbackList ? other.m_fontFallbackList->fontSelector() : 0;
return first == second
&& m_fontDescription == other.m_fontDescription
&& (m_fontFallbackList ? m_fontFallbackList->fontSelectorVersion() : 0) == (other.m_fontFallbackList ? other.m_fontFallbackList->fontSelectorVersion() : 0)
&& (m_fontFallbackList ? m_fontFallbackList->generation() : 0) == (other.m_fontFallbackList ? other.m_fontFallbackList->generation() : 0);
}
void Font::update(PassRefPtrWillBeRawPtr<FontSelector> fontSelector) const
{
// FIXME: It is pretty crazy that we are willing to just poke into a RefPtr, but it ends up
// being reasonably safe (because inherited fonts in the render tree pick up the new
// style anyway. Other copies are transient, e.g., the state in the GraphicsContext, and
// won't stick around long enough to get you in trouble). Still, this is pretty disgusting,
// and could eventually be rectified by using RefPtrs for Fonts themselves.
if (!m_fontFallbackList)
m_fontFallbackList = FontFallbackList::create();
m_fontFallbackList->invalidate(fontSelector);
}
void Font::drawText(GraphicsContext* context, const TextRunPaintInfo& runInfo, const FloatPoint& point, CustomFontNotReadyAction customFontNotReadyAction) const
{
// Don't draw anything while we are using custom fonts that are in the process of loading,
// except if the 'force' argument is set to true (in which case it will use a fallback
// font).
if (shouldSkipDrawing() && customFontNotReadyAction == DoNotPaintIfFontNotReady)
return;
CodePath codePathToUse = codePath(runInfo.run);
// FIXME: Use the fast code path once it handles partial runs with kerning and ligatures. See http://webkit.org/b/100050
if (codePathToUse != ComplexPath && fontDescription().typesettingFeatures() && (runInfo.from || runInfo.to != runInfo.run.length()))
codePathToUse = ComplexPath;
if (codePathToUse != ComplexPath) {
drawSimpleText(context, runInfo, point);
} else {
drawComplexText(context, runInfo, point);
}
}
void Font::drawEmphasisMarks(GraphicsContext* context, const TextRunPaintInfo& runInfo, const AtomicString& mark, const FloatPoint& point) const
{
if (shouldSkipDrawing())
return;
CodePath codePathToUse = codePath(runInfo.run);
// FIXME: Use the fast code path once it handles partial runs with kerning and ligatures. See http://webkit.org/b/100050
if (codePathToUse != ComplexPath && fontDescription().typesettingFeatures() && (runInfo.from || runInfo.to != runInfo.run.length()))
codePathToUse = ComplexPath;
if (codePathToUse != ComplexPath)
drawEmphasisMarksForSimpleText(context, runInfo, mark, point);
else
drawEmphasisMarksForComplexText(context, runInfo, mark, point);
}
static inline void updateGlyphOverflowFromBounds(const IntRectExtent& glyphBounds,
const FontMetrics& fontMetrics, GlyphOverflow* glyphOverflow)
{
glyphOverflow->top = max<int>(glyphOverflow->top,
glyphBounds.top() - (glyphOverflow->computeBounds ? 0 : fontMetrics.ascent()));
glyphOverflow->bottom = max<int>(glyphOverflow->bottom,
glyphBounds.bottom() - (glyphOverflow->computeBounds ? 0 : fontMetrics.descent()));
glyphOverflow->left = glyphBounds.left();
glyphOverflow->right = glyphBounds.right();
}
float Font::width(const TextRun& run, HashSet<const SimpleFontData*>* fallbackFonts, GlyphOverflow* glyphOverflow) const
{
CodePath codePathToUse = codePath(run);
if (codePathToUse != ComplexPath) {
// The complex path is more restrictive about returning fallback fonts than the simple path, so we need an explicit test to make their behaviors match.
if (!FontPlatformFeatures::canReturnFallbackFontsForComplexText())
fallbackFonts = 0;
// The simple path can optimize the case where glyph overflow is not observable.
if (codePathToUse != SimpleWithGlyphOverflowPath && (glyphOverflow && !glyphOverflow->computeBounds))
glyphOverflow = 0;
}
bool hasWordSpacingOrLetterSpacing = fontDescription().wordSpacing() || fontDescription().letterSpacing();
bool isCacheable = codePathToUse == ComplexPath
&& !hasWordSpacingOrLetterSpacing // Word spacing and letter spacing can change the width of a word.
&& !run.allowTabs(); // If we allow tabs and a tab occurs inside a word, the width of the word varies based on its position on the line.
WidthCacheEntry* cacheEntry = isCacheable
? m_fontFallbackList->widthCache().add(run, WidthCacheEntry())
: 0;
if (cacheEntry && cacheEntry->isValid()) {
if (glyphOverflow)
updateGlyphOverflowFromBounds(cacheEntry->glyphBounds, fontMetrics(), glyphOverflow);
return cacheEntry->width;
}
float result;
IntRectExtent glyphBounds;
if (codePathToUse == ComplexPath) {
result = floatWidthForComplexText(run, fallbackFonts, &glyphBounds);
} else {
ASSERT(!isCacheable);
result = floatWidthForSimpleText(run, fallbackFonts, glyphOverflow ? &glyphBounds : 0);
}
if (cacheEntry && (!fallbackFonts || fallbackFonts->isEmpty())) {
cacheEntry->glyphBounds = glyphBounds;
cacheEntry->width = result;
}
if (glyphOverflow)
updateGlyphOverflowFromBounds(glyphBounds, fontMetrics(), glyphOverflow);
return result;
}
float Font::width(const TextRun& run, int& charsConsumed, Glyph& glyphId) const
{
#if ENABLE(SVG_FONTS)
if (TextRun::RenderingContext* renderingContext = run.renderingContext())
return renderingContext->floatWidthUsingSVGFont(*this, run, charsConsumed, glyphId);
#endif
charsConsumed = run.length();
glyphId = 0;
return width(run);
}
FloatRect Font::selectionRectForText(const TextRun& run, const FloatPoint& point, int h, int from, int to, bool accountForGlyphBounds) const
{
to = (to == -1 ? run.length() : to);
CodePath codePathToUse = codePath(run);
// FIXME: Use the fast code path once it handles partial runs with kerning and ligatures. See http://webkit.org/b/100050
if (codePathToUse != ComplexPath && fontDescription().typesettingFeatures() && (from || to != run.length()))
codePathToUse = ComplexPath;
if (codePathToUse != ComplexPath)
return selectionRectForSimpleText(run, point, h, from, to, accountForGlyphBounds);
return selectionRectForComplexText(run, point, h, from, to);
}
int Font::offsetForPosition(const TextRun& run, float x, bool includePartialGlyphs) const
{
// FIXME: Use the fast code path once it handles partial runs with kerning and ligatures. See http://webkit.org/b/100050
if (codePath(run) != ComplexPath && !fontDescription().typesettingFeatures())
return offsetForPositionForSimpleText(run, x, includePartialGlyphs);
return offsetForPositionForComplexText(run, x, includePartialGlyphs);
}
void Font::setCodePath(CodePath p)
{
s_codePath = p;
}
CodePath Font::codePath()
{
return s_codePath;
}
CodePath Font::codePath(const TextRun& run) const
{
if (s_codePath != AutoPath)
return s_codePath;
#if ENABLE(SVG_FONTS)
if (run.renderingContext())
return SimplePath;
#endif
if (m_fontDescription.featureSettings() && m_fontDescription.featureSettings()->size() > 0 && m_fontDescription.letterSpacing() == 0)
return ComplexPath;
if (m_fontDescription.widthVariant() != RegularWidth)
return ComplexPath;
if (run.length() > 1 && fontDescription().typesettingFeatures())
return ComplexPath;
if (!run.characterScanForCodePath())
return SimplePath;
if (run.is8Bit())
return SimplePath;
// Start from 0 since drawing and highlighting also measure the characters before run->from.
return Character::characterRangeCodePath(run.characters16(), run.length());
}
void Font::willUseFontData(UChar32 character) const
{
const FontFamily& family = fontDescription().family();
if (m_fontFallbackList && m_fontFallbackList->fontSelector() && !family.familyIsEmpty())
m_fontFallbackList->fontSelector()->willUseFontData(fontDescription(), family.family(), character);
}
static inline bool isInRange(UChar32 character, UChar32 lowerBound, UChar32 upperBound)
{
return character >= lowerBound && character <= upperBound;
}
static bool shouldIgnoreRotation(UChar32 character)
{
if (character == 0x000A7 || character == 0x000A9 || character == 0x000AE)
return true;
if (character == 0x000B6 || character == 0x000BC || character == 0x000BD || character == 0x000BE)
return true;
if (isInRange(character, 0x002E5, 0x002EB))
return true;
if (isInRange(character, 0x01100, 0x011FF) || isInRange(character, 0x01401, 0x0167F) || isInRange(character, 0x01800, 0x018FF))
return true;
if (character == 0x02016 || character == 0x02018 || character == 0x02019 || character == 0x02020 || character == 0x02021
|| character == 0x2030 || character == 0x02031)
return true;
if (isInRange(character, 0x0203B, 0x0203D) || character == 0x02042 || character == 0x02044 || character == 0x02047
|| character == 0x02048 || character == 0x02049 || character == 0x2051)
return true;
if (isInRange(character, 0x02065, 0x02069) || isInRange(character, 0x020DD, 0x020E0)
|| isInRange(character, 0x020E2, 0x020E4) || isInRange(character, 0x02100, 0x02117)
|| isInRange(character, 0x02119, 0x02131) || isInRange(character, 0x02133, 0x0213F))
return true;
if (isInRange(character, 0x02145, 0x0214A) || character == 0x0214C || character == 0x0214D
|| isInRange(character, 0x0214F, 0x0218F))
return true;
if (isInRange(character, 0x02300, 0x02307) || isInRange(character, 0x0230C, 0x0231F)
|| isInRange(character, 0x02322, 0x0232B) || isInRange(character, 0x0237D, 0x0239A)
|| isInRange(character, 0x023B4, 0x023B6) || isInRange(character, 0x023BA, 0x023CF)
|| isInRange(character, 0x023D1, 0x023DB) || isInRange(character, 0x023E2, 0x024FF))
return true;
if (isInRange(character, 0x025A0, 0x02619) || isInRange(character, 0x02620, 0x02767)
|| isInRange(character, 0x02776, 0x02793) || isInRange(character, 0x02B12, 0x02B2F)
|| isInRange(character, 0x02B4D, 0x02BFF) || isInRange(character, 0x02E80, 0x03007))
return true;
if (character == 0x03012 || character == 0x03013 || isInRange(character, 0x03020, 0x0302F)
|| isInRange(character, 0x03031, 0x0309F) || isInRange(character, 0x030A1, 0x030FB)
|| isInRange(character, 0x030FD, 0x0A4CF))
return true;
if (isInRange(character, 0x0A840, 0x0A87F) || isInRange(character, 0x0A960, 0x0A97F)
|| isInRange(character, 0x0AC00, 0x0D7FF) || isInRange(character, 0x0E000, 0x0FAFF))
return true;
if (isInRange(character, 0x0FE10, 0x0FE1F) || isInRange(character, 0x0FE30, 0x0FE48)
|| isInRange(character, 0x0FE50, 0x0FE57) || isInRange(character, 0x0FE5F, 0x0FE62)
|| isInRange(character, 0x0FE67, 0x0FE6F))
return true;
if (isInRange(character, 0x0FF01, 0x0FF07) || isInRange(character, 0x0FF0A, 0x0FF0C)
|| isInRange(character, 0x0FF0E, 0x0FF19) || isInRange(character, 0x0FF1F, 0x0FF3A))
return true;
if (character == 0x0FF3C || character == 0x0FF3E)
return true;
if (isInRange(character, 0x0FF40, 0x0FF5A) || isInRange(character, 0x0FFE0, 0x0FFE2)
|| isInRange(character, 0x0FFE4, 0x0FFE7) || isInRange(character, 0x0FFF0, 0x0FFF8)
|| character == 0x0FFFD)
return true;
if (isInRange(character, 0x13000, 0x1342F) || isInRange(character, 0x1B000, 0x1B0FF)
|| isInRange(character, 0x1D000, 0x1D1FF) || isInRange(character, 0x1D300, 0x1D37F)
|| isInRange(character, 0x1F000, 0x1F64F) || isInRange(character, 0x1F680, 0x1F77F))
return true;
if (isInRange(character, 0x20000, 0x2FFFD) || isInRange(character, 0x30000, 0x3FFFD))
return true;
return false;
}
static inline std::pair<GlyphData, GlyphPage*> glyphDataAndPageForNonCJKCharacterWithGlyphOrientation(UChar32 character, NonCJKGlyphOrientation orientation, GlyphData& data, GlyphPage* page, unsigned pageNumber)
{
if (orientation == NonCJKGlyphOrientationUpright || shouldIgnoreRotation(character)) {
RefPtr<SimpleFontData> uprightFontData = data.fontData->uprightOrientationFontData();
GlyphPageTreeNode* uprightNode = GlyphPageTreeNode::getRootChild(uprightFontData.get(), pageNumber);
GlyphPage* uprightPage = uprightNode->page();
if (uprightPage) {
GlyphData uprightData = uprightPage->glyphDataForCharacter(character);
// If the glyphs are the same, then we know we can just use the horizontal glyph rotated vertically to be upright.
if (data.glyph == uprightData.glyph)
return make_pair(data, page);
// The glyphs are distinct, meaning that the font has a vertical-right glyph baked into it. We can't use that
// glyph, so we fall back to the upright data and use the horizontal glyph.
if (uprightData.fontData)
return make_pair(uprightData, uprightPage);
}
} else if (orientation == NonCJKGlyphOrientationVerticalRight) {
RefPtr<SimpleFontData> verticalRightFontData = data.fontData->verticalRightOrientationFontData();
GlyphPageTreeNode* verticalRightNode = GlyphPageTreeNode::getRootChild(verticalRightFontData.get(), pageNumber);
GlyphPage* verticalRightPage = verticalRightNode->page();
if (verticalRightPage) {
GlyphData verticalRightData = verticalRightPage->glyphDataForCharacter(character);
// If the glyphs are distinct, we will make the assumption that the font has a vertical-right glyph baked
// into it.
if (data.glyph != verticalRightData.glyph)
return make_pair(data, page);
// The glyphs are identical, meaning that we should just use the horizontal glyph.
if (verticalRightData.fontData)
return make_pair(verticalRightData, verticalRightPage);
}
}
return make_pair(data, page);
}
std::pair<GlyphData, GlyphPage*> Font::glyphDataAndPageForCharacter(UChar32 c, bool mirror, FontDataVariant variant) const
{
ASSERT(isMainThread());
if (variant == AutoVariant) {
if (m_fontDescription.variant() == FontVariantSmallCaps && !primaryFont()->isSVGFont()) {
UChar32 upperC = toUpper(c);
if (upperC != c) {
c = upperC;
variant = SmallCapsVariant;
} else {
variant = NormalVariant;
}
} else {
variant = NormalVariant;
}
}
if (mirror)
c = mirroredChar(c);
unsigned pageNumber = (c / GlyphPage::size);
GlyphPageTreeNode* node = m_fontFallbackList->getPageNode(pageNumber);
if (!node) {
node = GlyphPageTreeNode::getRootChild(fontDataAt(0), pageNumber);
m_fontFallbackList->setPageNode(pageNumber, node);
}
GlyphPage* page = 0;
if (variant == NormalVariant) {
// Fastest loop, for the common case (normal variant).
while (true) {
page = node->page();
if (page) {
GlyphData data = page->glyphDataForCharacter(c);
if (data.fontData && (data.fontData->platformData().orientation() == Horizontal || data.fontData->isTextOrientationFallback()))
return make_pair(data, page);
if (data.fontData) {
if (Character::isCJKIdeographOrSymbol(c)) {
if (!data.fontData->hasVerticalGlyphs()) {
// Use the broken ideograph font data. The broken ideograph font will use the horizontal width of glyphs
// to make sure you get a square (even for broken glyphs like symbols used for punctuation).
variant = BrokenIdeographVariant;
break;
}
} else {
return glyphDataAndPageForNonCJKCharacterWithGlyphOrientation(c, m_fontDescription.nonCJKGlyphOrientation(), data, page, pageNumber);
}
return make_pair(data, page);
}
if (node->isSystemFallback())
break;
}
// Proceed with the fallback list.
node = node->getChild(fontDataAt(node->level()), pageNumber);
m_fontFallbackList->setPageNode(pageNumber, node);
}
}
if (variant != NormalVariant) {
while (true) {
page = node->page();
if (page) {
GlyphData data = page->glyphDataForCharacter(c);
if (data.fontData) {
// The variantFontData function should not normally return 0.
// But if it does, we will just render the capital letter big.
RefPtr<SimpleFontData> variantFontData = data.fontData->variantFontData(m_fontDescription, variant);
if (!variantFontData)
return make_pair(data, page);
GlyphPageTreeNode* variantNode = GlyphPageTreeNode::getRootChild(variantFontData.get(), pageNumber);
GlyphPage* variantPage = variantNode->page();
if (variantPage) {
GlyphData data = variantPage->glyphDataForCharacter(c);
if (data.fontData)
return make_pair(data, variantPage);
}
// Do not attempt system fallback off the variantFontData. This is the very unlikely case that
// a font has the lowercase character but the small caps font does not have its uppercase version.
return make_pair(variantFontData->missingGlyphData(), page);
}
if (node->isSystemFallback())
break;
}
// Proceed with the fallback list.
node = node->getChild(fontDataAt(node->level()), pageNumber);
m_fontFallbackList->setPageNode(pageNumber, node);
}
}
ASSERT(page);
ASSERT(node->isSystemFallback());
// System fallback is character-dependent. When we get here, we
// know that the character in question isn't in the system fallback
// font's glyph page. Try to lazily create it here.
// FIXME: Unclear if this should normalizeSpaces above 0xFFFF.
// Doing so changes fast/text/international/plane2-diffs.html
UChar32 characterToRender = c;
if (characterToRender <= 0xFFFF)
characterToRender = Character::normalizeSpaces(characterToRender);
const SimpleFontData* fontDataToSubstitute = fontDataAt(0)->fontDataForCharacter(characterToRender);
RefPtr<SimpleFontData> characterFontData = FontCache::fontCache()->fallbackFontForCharacter(m_fontDescription, characterToRender, fontDataToSubstitute);
if (characterFontData) {
if (characterFontData->platformData().orientation() == Vertical && !characterFontData->hasVerticalGlyphs() && Character::isCJKIdeographOrSymbol(c))
variant = BrokenIdeographVariant;
if (variant != NormalVariant)
characterFontData = characterFontData->variantFontData(m_fontDescription, variant);
}
if (characterFontData) {
// Got the fallback glyph and font.
GlyphPage* fallbackPage = GlyphPageTreeNode::getRootChild(characterFontData.get(), pageNumber)->page();
GlyphData data = fallbackPage && fallbackPage->glyphForCharacter(c) ? fallbackPage->glyphDataForCharacter(c) : characterFontData->missingGlyphData();
// Cache it so we don't have to do system fallback again next time.
if (variant == NormalVariant) {
page->setGlyphDataForCharacter(c, data.glyph, data.fontData);
data.fontData->setMaxGlyphPageTreeLevel(max(data.fontData->maxGlyphPageTreeLevel(), node->level()));
if (!Character::isCJKIdeographOrSymbol(c) && data.fontData->platformData().orientation() != Horizontal && !data.fontData->isTextOrientationFallback())
return glyphDataAndPageForNonCJKCharacterWithGlyphOrientation(c, m_fontDescription.nonCJKGlyphOrientation(), data, page, pageNumber);
}
return make_pair(data, page);
}
// Even system fallback can fail; use the missing glyph in that case.
// FIXME: It would be nicer to use the missing glyph from the last resort font instead.
GlyphData data = primaryFont()->missingGlyphData();
if (variant == NormalVariant) {
page->setGlyphDataForCharacter(c, data.glyph, data.fontData);
data.fontData->setMaxGlyphPageTreeLevel(max(data.fontData->maxGlyphPageTreeLevel(), node->level()));
}
return make_pair(data, page);
}
bool Font::primaryFontHasGlyphForCharacter(UChar32 character) const
{
unsigned pageNumber = (character / GlyphPage::size);
GlyphPageTreeNode* node = GlyphPageTreeNode::getRootChild(primaryFont(), pageNumber);
GlyphPage* page = node->page();
return page && page->glyphForCharacter(character);
}
// FIXME: This function may not work if the emphasis mark uses a complex script, but none of the
// standard emphasis marks do so.
bool Font::getEmphasisMarkGlyphData(const AtomicString& mark, GlyphData& glyphData) const
{
if (mark.isEmpty())
return false;
UChar32 character = mark[0];
if (U16_IS_SURROGATE(character)) {
if (!U16_IS_SURROGATE_LEAD(character))
return false;
if (mark.length() < 2)
return false;
UChar low = mark[1];
if (!U16_IS_TRAIL(low))
return false;
character = U16_GET_SUPPLEMENTARY(character, low);
}
glyphData = glyphDataForCharacter(character, false, EmphasisMarkVariant);
return true;
}
int Font::emphasisMarkAscent(const AtomicString& mark) const
{
FontCachePurgePreventer purgePreventer;
GlyphData markGlyphData;
if (!getEmphasisMarkGlyphData(mark, markGlyphData))
return 0;
const SimpleFontData* markFontData = markGlyphData.fontData;
ASSERT(markFontData);
if (!markFontData)
return 0;
return markFontData->fontMetrics().ascent();
}
int Font::emphasisMarkDescent(const AtomicString& mark) const
{
FontCachePurgePreventer purgePreventer;
GlyphData markGlyphData;
if (!getEmphasisMarkGlyphData(mark, markGlyphData))
return 0;
const SimpleFontData* markFontData = markGlyphData.fontData;
ASSERT(markFontData);
if (!markFontData)
return 0;
return markFontData->fontMetrics().descent();
}
int Font::emphasisMarkHeight(const AtomicString& mark) const
{
FontCachePurgePreventer purgePreventer;
GlyphData markGlyphData;
if (!getEmphasisMarkGlyphData(mark, markGlyphData))
return 0;
const SimpleFontData* markFontData = markGlyphData.fontData;
ASSERT(markFontData);
if (!markFontData)
return 0;
return markFontData->fontMetrics().height();
}
float Font::getGlyphsAndAdvancesForSimpleText(const TextRunPaintInfo& runInfo, GlyphBuffer& glyphBuffer, ForTextEmphasisOrNot forTextEmphasis) const
{
float initialAdvance;
WidthIterator it(this, runInfo.run, 0, false, forTextEmphasis);
it.advance(runInfo.from);
float beforeWidth = it.m_runWidthSoFar;
it.advance(runInfo.to, &glyphBuffer);
if (glyphBuffer.isEmpty())
return 0;
float afterWidth = it.m_runWidthSoFar;
if (runInfo.run.rtl()) {
it.advance(runInfo.run.length());
initialAdvance = it.m_runWidthSoFar - afterWidth;
glyphBuffer.reverse();
} else {
initialAdvance = beforeWidth;
}
return initialAdvance;
}
void Font::drawSimpleText(GraphicsContext* context, const TextRunPaintInfo& runInfo, const FloatPoint& point) const
{
// This glyph buffer holds our glyphs+advances+font data for each glyph.
GlyphBuffer glyphBuffer;
float startX = point.x() + getGlyphsAndAdvancesForSimpleText(runInfo, glyphBuffer);
if (glyphBuffer.isEmpty())
return;
FloatPoint startPoint(startX, point.y());
drawGlyphBuffer(context, runInfo, glyphBuffer, startPoint);
}
void Font::drawEmphasisMarksForSimpleText(GraphicsContext* context, const TextRunPaintInfo& runInfo, const AtomicString& mark, const FloatPoint& point) const
{
GlyphBuffer glyphBuffer;
float initialAdvance = getGlyphsAndAdvancesForSimpleText(runInfo, glyphBuffer, ForTextEmphasis);
if (glyphBuffer.isEmpty())
return;
drawEmphasisMarks(context, runInfo, glyphBuffer, mark, FloatPoint(point.x() + initialAdvance, point.y()));
}
void Font::drawGlyphBuffer(GraphicsContext* context, const TextRunPaintInfo& runInfo, const GlyphBuffer& glyphBuffer, const FloatPoint& point) const
{
// Draw each contiguous run of glyphs that use the same font data.
const SimpleFontData* fontData = glyphBuffer.fontDataAt(0);
FloatPoint startPoint(point);
FloatPoint nextPoint = startPoint + glyphBuffer.advanceAt(0);
unsigned lastFrom = 0;
unsigned nextGlyph = 1;
#if ENABLE(SVG_FONTS)
TextRun::RenderingContext* renderingContext = runInfo.run.renderingContext();
#endif
while (nextGlyph < glyphBuffer.size()) {
const SimpleFontData* nextFontData = glyphBuffer.fontDataAt(nextGlyph);
if (nextFontData != fontData) {
#if ENABLE(SVG_FONTS)
if (renderingContext && fontData->isSVGFont())
renderingContext->drawSVGGlyphs(context, runInfo.run, fontData, glyphBuffer, lastFrom, nextGlyph - lastFrom, startPoint);
else
#endif
drawGlyphs(context, fontData, glyphBuffer, lastFrom, nextGlyph - lastFrom, startPoint, runInfo.bounds);
lastFrom = nextGlyph;
fontData = nextFontData;
startPoint = nextPoint;
}
nextPoint += glyphBuffer.advanceAt(nextGlyph);
nextGlyph++;
}
#if ENABLE(SVG_FONTS)
if (renderingContext && fontData->isSVGFont())
renderingContext->drawSVGGlyphs(context, runInfo.run, fontData, glyphBuffer, lastFrom, nextGlyph - lastFrom, startPoint);
else
#endif
drawGlyphs(context, fontData, glyphBuffer, lastFrom, nextGlyph - lastFrom, startPoint, runInfo.bounds);
}
inline static float offsetToMiddleOfGlyph(const SimpleFontData* fontData, Glyph glyph)
{
if (fontData->platformData().orientation() == Horizontal) {
FloatRect bounds = fontData->boundsForGlyph(glyph);
return bounds.x() + bounds.width() / 2;
}
// FIXME: Use glyph bounds once they make sense for vertical fonts.
return fontData->widthForGlyph(glyph) / 2;
}
inline static float offsetToMiddleOfAdvanceAtIndex(const GlyphBuffer& glyphBuffer, size_t i)
{
return glyphBuffer.advanceAt(i).width() / 2;
}
void Font::drawEmphasisMarks(GraphicsContext* context, const TextRunPaintInfo& runInfo, const GlyphBuffer& glyphBuffer, const AtomicString& mark, const FloatPoint& point) const
{
FontCachePurgePreventer purgePreventer;
GlyphData markGlyphData;
if (!getEmphasisMarkGlyphData(mark, markGlyphData))
return;
const SimpleFontData* markFontData = markGlyphData.fontData;
ASSERT(markFontData);
if (!markFontData)
return;
Glyph markGlyph = markGlyphData.glyph;
Glyph spaceGlyph = markFontData->spaceGlyph();
float middleOfLastGlyph = offsetToMiddleOfAdvanceAtIndex(glyphBuffer, 0);
FloatPoint startPoint(point.x() + middleOfLastGlyph - offsetToMiddleOfGlyph(markFontData, markGlyph), point.y());
GlyphBuffer markBuffer;
for (unsigned i = 0; i + 1 < glyphBuffer.size(); ++i) {
float middleOfNextGlyph = offsetToMiddleOfAdvanceAtIndex(glyphBuffer, i + 1);
float advance = glyphBuffer.advanceAt(i).width() - middleOfLastGlyph + middleOfNextGlyph;
markBuffer.add(glyphBuffer.glyphAt(i) ? markGlyph : spaceGlyph, markFontData, advance);
middleOfLastGlyph = middleOfNextGlyph;
}
markBuffer.add(glyphBuffer.glyphAt(glyphBuffer.size() - 1) ? markGlyph : spaceGlyph, markFontData, 0);
drawGlyphBuffer(context, runInfo, markBuffer, startPoint);
}
float Font::floatWidthForSimpleText(const TextRun& run, HashSet<const SimpleFontData*>* fallbackFonts, IntRectExtent* glyphBounds) const
{
WidthIterator it(this, run, fallbackFonts, glyphBounds);
it.advance(run.length());
if (glyphBounds) {
glyphBounds->setTop(floorf(-it.minGlyphBoundingBoxY()));
glyphBounds->setBottom(ceilf(it.maxGlyphBoundingBoxY()));
glyphBounds->setLeft(floorf(it.firstGlyphOverflow()));
glyphBounds->setRight(ceilf(it.lastGlyphOverflow()));
}
return it.m_runWidthSoFar;
}
FloatRect Font::pixelSnappedSelectionRect(float fromX, float toX, float y, float height)
{
// Using roundf() rather than ceilf() for the right edge as a compromise to
// ensure correct caret positioning.
float roundedX = roundf(fromX);
return FloatRect(roundedX, y, roundf(toX - roundedX), height);
}
FloatRect Font::selectionRectForSimpleText(const TextRun& run, const FloatPoint& point, int h, int from, int to, bool accountForGlyphBounds) const
{
WidthIterator it(this, run, 0, accountForGlyphBounds);
it.advance(from);
float fromX = it.m_runWidthSoFar;
it.advance(to);
float toX = it.m_runWidthSoFar;
if (run.rtl()) {
it.advance(run.length());
float totalWidth = it.m_runWidthSoFar;
float beforeWidth = fromX;
float afterWidth = toX;
fromX = totalWidth - afterWidth;
toX = totalWidth - beforeWidth;
}
return pixelSnappedSelectionRect(point.x() + fromX, point.x() + toX,
accountForGlyphBounds ? it.minGlyphBoundingBoxY() : point.y(),
accountForGlyphBounds ? it.maxGlyphBoundingBoxY() - it.minGlyphBoundingBoxY() : h);
}
int Font::offsetForPositionForSimpleText(const TextRun& run, float x, bool includePartialGlyphs) const
{
float delta = x;
WidthIterator it(this, run);
unsigned offset;
if (run.rtl()) {
delta -= floatWidthForSimpleText(run);
while (1) {
offset = it.m_currentCharacter;
float w;
if (!it.advanceOneCharacter(w))
break;
delta += w;
if (includePartialGlyphs) {
if (delta - w / 2 >= 0)
break;
} else {
if (delta >= 0)
break;
}
}
} else {
while (1) {
offset = it.m_currentCharacter;
float w;
if (!it.advanceOneCharacter(w))
break;
delta -= w;
if (includePartialGlyphs) {
if (delta + w / 2 <= 0)
break;
} else {
if (delta <= 0)
break;
}
}
}
return offset;
}
} // namespace blink