Font::CodePath Font::codePath(const TextRun& run) const
{
if (s_codePath != Auto)
return s_codePath;
#if ENABLE(SVG_FONTS)
if (run.renderingContext())
return Simple;
#endif
if (m_fontDescription.featureSettings() && m_fontDescription.featureSettings()->size() > 0)
return Complex;
if (run.length() > 1 && !WidthIterator::supportsTypesettingFeatures(*this))
return Complex;
if (!run.characterScanForCodePath())
return Simple;
if (run.is8Bit())
return Simple;
// Start from 0 since drawing and highlighting also measure the characters before run->from.
return characterRangeCodePath(run.characters16(), run.length());
}
static void normalizeCharacters(const TextRun& run, unsigned length, UChar* destination, unsigned* destinationLength)
{
unsigned position = 0;
bool error = false;
const UChar* source;
String stringFor8BitRun;
if (run.is8Bit()) {
stringFor8BitRun = String::make16BitFrom8BitSource(run.characters8(), run.length());
source = stringFor8BitRun.characters16();
} else {
source = run.characters16();
}
*destinationLength = 0;
while (position < length) {
UChar32 character;
U16_NEXT(source, position, length, character);
// Don't normalize tabs as they are not treated as spaces for word-end.
if (run.normalizeSpace() && Character::isNormalizedCanvasSpaceCharacter(character))
character = spaceCharacter;
else if (Character::treatAsSpace(character) && character != noBreakSpaceCharacter)
character = spaceCharacter;
else if (Character::treatAsZeroWidthSpaceInComplexScript(character))
character = zeroWidthSpaceCharacter;
U16_APPEND(destination, *destinationLength, length, character, error);
ASSERT_UNUSED(error, !error);
}
}
int Font::offsetForPositionForComplexText(const TextRun& run, float xFloat, bool includePartialGlyphs) const
{
#if USE(FREETYPE)
if (!primaryFont()->platformData().m_pattern)
return offsetForPositionForSimpleText(run, xFloat, includePartialGlyphs);
#endif
// FIXME: This truncation is not a problem for HTML, but only affects SVG, which passes floating-point numbers
// to Font::offsetForPosition(). Bug http://webkit.org/b/40673 tracks fixing this problem.
int x = static_cast<int>(xFloat);
PangoLayout* layout = getDefaultPangoLayout(run);
setPangoAttributes(this, run, layout);
gchar* utf8 = convertUniCharToUTF8(run.characters16(), run.length(), 0, run.length());
pango_layout_set_text(layout, utf8, -1);
int index, trailing;
pango_layout_xy_to_index(layout, x * PANGO_SCALE, 1, &index, &trailing);
glong offset = g_utf8_pointer_to_offset(utf8, utf8 + index);
if (includePartialGlyphs)
offset += trailing;
g_free(utf8);
g_object_unref(layout);
return offset;
}
UniscribeHelperTextRun::UniscribeHelperTextRun(const TextRun& run,
const Font& font)
: UniscribeHelper(0, run.length(), run.rtl(),
font.primaryFont()->platformData().hfont(),
font.primaryFont()->platformData().scriptCache(),
font.primaryFont()->platformData().scriptFontProperties(),
font.primaryFont()->spaceGlyph())
, m_font(&font)
, m_fontIndex(0)
{
if (run.is8Bit()) {
m_stringFor8BitRun = String::make16BitFrom8BitSource(run.characters8(), run.length());
setInput(m_stringFor8BitRun.characters16());
} else {
setInput(run.characters16());
}
setDirectionalOverride(run.directionalOverride());
setLetterSpacing(font.letterSpacing());
setSpaceWidth(font.spaceWidth());
setWordSpacing(font.wordSpacing());
setAscent(font.fontMetrics().ascent());
setRangeProperties(font.fontDescription().featureSettings());
init();
// Expansion is the amount to add to make justification happen. This
// should be done after Init() so all the runs are already measured.
if (run.expansion() > 0)
justify(run.expansion());
}
static void normalizeCharacters(const TextRun& run, UChar* destination, int length)
{
int position = 0;
bool error = false;
const UChar* source;
String stringFor8BitRun;
if (run.is8Bit()) {
stringFor8BitRun = String::make16BitFrom8BitSource(run.characters8(), run.length());
source = stringFor8BitRun.characters16();
} else
source = run.characters16();
while (position < length) {
UChar32 character;
int nextPosition = position;
U16_NEXT(source, nextPosition, length, character);
// Don't normalize tabs as they are not treated as spaces for word-end.
if (Font::treatAsSpace(character) && character != '\t')
character = ' ';
else if (Font::treatAsZeroWidthSpaceInComplexScript(character))
character = zeroWidthSpace;
U16_APPEND(destination, position, length, character, error);
ASSERT_UNUSED(error, !error);
position = nextPosition;
}
}
bool ShapeResultSpacing::isFirstRun(const TextRun& run) const
{
if (&run == &m_textRun)
return true;
return run.is8Bit()
? run.characters8() == m_textRun.characters8()
: run.characters16() == m_textRun.characters16();
}
TextDirection directionForRun(TextRun& run, bool* hasStrongDirectionality)
{
if (!hasStrongDirectionality) {
// 8bit is Latin-1 and therefore is always LTR.
if (run.is8Bit())
return LTR;
// length == 1 for more than 90% of cases of width() for CJK text.
if (run.length() == 1 && U16_IS_SINGLE(run.characters16()[0]))
return directionForCharacter(run.characters16()[0]);
}
BidiResolver<TextRunIterator, BidiCharacterRun> bidiResolver;
bidiResolver.setStatus(BidiStatus(run.direction(), run.directionalOverride()));
bidiResolver.setPositionIgnoringNestedIsolates(TextRunIterator(&run, 0));
return bidiResolver.determineParagraphDirectionality(hasStrongDirectionality);
}
void computeNormalizedSpaces(const TextRun& run, bool mirror, String& normalizedSpacesStringCache)
{
if (normalizedSpacesStringCache.length() == static_cast<unsigned>(run.charactersLength()))
return;
if (run.is8Bit())
normalizedSpacesStringCache = Font::normalizeSpaces(run.characters8(), run.charactersLength());
else
normalizedSpacesStringCache = Font::normalizeSpaces(run.characters16(), run.charactersLength());
if (mirror)
normalizedSpacesStringCache = createStringWithMirroredCharacters(normalizedSpacesStringCache);
}
FloatRect Font::selectionRectForComplexText(const TextRun& run, const FloatPoint& point, int h, int from, int to) const
{
#if USE(FREETYPE)
if (!primaryFont()->platformData().m_pattern)
return selectionRectForSimpleText(run, point, h, from, to);
#endif
PangoLayout* layout = getDefaultPangoLayout(run);
setPangoAttributes(this, run, layout);
gchar* utf8 = convertUniCharToUTF8(run.characters16(), run.length(), 0, run.length());
pango_layout_set_text(layout, utf8, -1);
char* start = g_utf8_offset_to_pointer(utf8, from);
char* end = g_utf8_offset_to_pointer(start, to - from);
if (run.ltr()) {
from = start - utf8;
to = end - utf8;
} else {
from = end - utf8;
to = start - utf8;
}
PangoLayoutLine* layoutLine = pango_layout_get_line_readonly(layout, 0);
int xPos;
xPos = 0;
if (from < layoutLine->length)
pango_layout_line_index_to_x(layoutLine, from, FALSE, &xPos);
float beforeWidth = PANGO_PIXELS_FLOOR(xPos);
xPos = 0;
if (run.ltr() || to < layoutLine->length)
pango_layout_line_index_to_x(layoutLine, to, FALSE, &xPos);
float afterWidth = PANGO_PIXELS(xPos);
g_free(utf8);
g_object_unref(layout);
return FloatRect(point.x() + beforeWidth, point.y(), afterWidth - beforeWidth, h);
}
float Font::floatWidthForComplexText(const TextRun& run, HashSet<const SimpleFontData*>* fallbackFonts, GlyphOverflow* overflow) const
{
#if USE(FREETYPE)
if (!primaryFont()->platformData().m_pattern)
return floatWidthForSimpleText(run, fallbackFonts, overflow);
#endif
if (!run.length())
return 0.0f;
PangoLayout* layout = getDefaultPangoLayout(run);
setPangoAttributes(this, run, layout);
gchar* utf8 = convertUniCharToUTF8(run.characters16(), run.length(), 0, run.length());
pango_layout_set_text(layout, utf8, -1);
int width;
pango_layout_get_pixel_size(layout, &width, 0);
g_free(utf8);
g_object_unref(layout);
return width;
}
float ShapeResult::fillGlyphBufferForTextEmphasisRun(GlyphBuffer* glyphBuffer,
const RunInfo* run, const TextRun& textRun, const GlyphData* emphasisData,
float initialAdvance, unsigned from, unsigned to, unsigned runOffset)
{
if (!run)
return 0;
unsigned graphemesInCluster = 1;
float clusterAdvance = 0;
FloatPoint glyphCenter = emphasisData->fontData->
boundsForGlyph(emphasisData->glyph).center();
TextDirection direction = textRun.direction();
// A "cluster" in this context means a cluster as it is used by HarfBuzz:
// The minimal group of characters and corresponding glyphs, that cannot be broken
// down further from a text shaping point of view.
// A cluster can contain multiple glyphs and grapheme clusters, with mutually
// overlapping boundaries. Below we count grapheme clusters per HarfBuzz clusters,
// then linearly split the sum of corresponding glyph advances by the number of
// grapheme clusters in order to find positions for emphasis mark drawing.
uint16_t clusterStart = direction == RTL
? run->m_startIndex + run->m_numCharacters + runOffset
: run->glyphToCharacterIndex(0) + runOffset;
float advanceSoFar = initialAdvance;
unsigned numGlyphs = run->m_numGlyphs;
for (unsigned i = 0; i < numGlyphs; ++i) {
const HarfBuzzRunGlyphData& glyphData = run->m_glyphData[i];
uint16_t currentCharacterIndex = run->m_startIndex + glyphData.characterIndex + runOffset;
bool isRunEnd = (i + 1 == numGlyphs);
bool isClusterEnd = isRunEnd || (run->glyphToCharacterIndex(i + 1) + runOffset != currentCharacterIndex);
if ((direction == RTL && currentCharacterIndex >= to) || (direction != RTL && currentCharacterIndex < from)) {
advanceSoFar += glyphData.advance;
direction == RTL ? --clusterStart : ++clusterStart;
continue;
}
clusterAdvance += glyphData.advance;
if (textRun.is8Bit()) {
float glyphAdvanceX = glyphData.advance;
if (Character::canReceiveTextEmphasis(textRun[currentCharacterIndex])) {
addEmphasisMark(glyphBuffer, emphasisData, glyphCenter, advanceSoFar + glyphAdvanceX / 2);
}
advanceSoFar += glyphAdvanceX;
} else if (isClusterEnd) {
uint16_t clusterEnd;
if (direction == RTL)
clusterEnd = currentCharacterIndex;
else
clusterEnd = isRunEnd ? run->m_startIndex + run->m_numCharacters + runOffset : run->glyphToCharacterIndex(i + 1) + runOffset;
graphemesInCluster = countGraphemesInCluster(textRun.characters16(), textRun.charactersLength(), clusterStart, clusterEnd);
if (!graphemesInCluster || !clusterAdvance)
continue;
float glyphAdvanceX = clusterAdvance / graphemesInCluster;
for (unsigned j = 0; j < graphemesInCluster; ++j) {
// Do not put emphasis marks on space, separator, and control characters.
if (Character::canReceiveTextEmphasis(textRun[currentCharacterIndex]))
addEmphasisMark(glyphBuffer, emphasisData, glyphCenter, advanceSoFar + glyphAdvanceX / 2);
advanceSoFar += glyphAdvanceX;
}
clusterStart = clusterEnd;
clusterAdvance = 0;
}
}
return advanceSoFar - initialAdvance;
}
static int generateComponents(TextRunComponents* components, const Font &font, const TextRun &run)
{
int letterSpacing = font.letterSpacing();
int wordSpacing = font.wordSpacing();
int padding = run.expansion();
int numSpaces = 0;
if (padding) {
for (int i = 0; i < run.length(); i++)
if (Font::treatAsSpace(run[i]))
++numSpaces;
}
int offset = 0;
if (letterSpacing) {
// need to draw every letter on it's own
int start = 0;
if (Font::treatAsSpace(run[0])) {
int add = 0;
if (numSpaces) {
add = padding/numSpaces;
padding -= add;
--numSpaces;
}
components->append(TextRunComponent(1, font, offset));
offset += add + letterSpacing + components->last().m_width;
start = 1;
}
for (int i = 1; i < run.length(); ++i) {
UChar ch = run[i];
if (U16_IS_LEAD(ch) && U16_IS_TRAIL(run[i-1]))
ch = U16_GET_SUPPLEMENTARY(ch, run[i-1]);
if (U16_IS_TRAIL(ch) || U_GET_GC_MASK(ch) & U_GC_MN_MASK)
continue;
if (Font::treatAsSpace(run[i])) {
int add = 0;
if (i - start > 0) {
components->append(TextRunComponent(run.characters16() + start, i - start,
run, font, offset));
offset += components->last().m_width + letterSpacing;
}
if (numSpaces) {
add = padding/numSpaces;
padding -= add;
--numSpaces;
}
components->append(TextRunComponent(1, font, offset));
offset += wordSpacing + add + components->last().m_width + letterSpacing;
start = i + 1;
continue;
}
if (i - start > 0) {
components->append(TextRunComponent(run.characters16() + start, i - start,
run,
font, offset));
offset += components->last().m_width + letterSpacing;
}
start = i;
}
if (run.length() - start > 0) {
components->append(TextRunComponent(run.characters16() + start, run.length() - start,
run,
font, offset));
offset += components->last().m_width;
}
offset += letterSpacing;
} else {
int start = 0;
for (int i = 0; i < run.length(); ++i) {
if (Font::treatAsSpace(run[i])) {
if (i - start > 0) {
components->append(TextRunComponent(run.characters16() + start, i - start,
run,
font, offset));
offset += components->last().m_width;
}
int add = 0;
if (numSpaces) {
add = padding/numSpaces;
padding -= add;
--numSpaces;
}
components->append(TextRunComponent(1, font, offset));
offset += add + components->last().m_width;
if (i)
offset += wordSpacing;
start = i + 1;
}
}
if (run.length() - start > 0) {
components->append(TextRunComponent(run.characters16() + start, run.length() - start,
run,
font, offset));
offset += components->last().m_width;
}
}
return offset;
}
void Font::drawComplexText(GraphicsContext* context, const TextRun& run, const FloatPoint& point, int from, int to) const
{
#if USE(FREETYPE)
if (!primaryFont()->platformData().m_pattern) {
drawSimpleText(context, run, point, from, to);
return;
}
#endif
cairo_t* cr = context->platformContext()->cr();
PangoLayout* layout = pango_cairo_create_layout(cr);
setPangoAttributes(this, run, layout);
gchar* utf8 = convertUniCharToUTF8(run.characters16(), run.length(), 0, run.length());
pango_layout_set_text(layout, utf8, -1);
// Our layouts are single line
PangoLayoutLine* layoutLine = pango_layout_get_line_readonly(layout, 0);
// Get the region where this text will be laid out. We will use it to clip
// the Cairo context, for when we are only painting part of the text run and
// to calculate the size of the shadow buffer.
PangoRegionType partialRegion = 0;
char* start = g_utf8_offset_to_pointer(utf8, from);
char* end = g_utf8_offset_to_pointer(start, to - from);
int ranges[] = {start - utf8, end - utf8};
#if PLATFORM(GTK)
partialRegion = gdk_pango_layout_line_get_clip_region(layoutLine, 0, 0, ranges, 1);
#else
partialRegion = getClipRegionFromPangoLayoutLine(layoutLine, ranges);
#endif
drawGlyphsShadow(context, point, layoutLine, partialRegion);
cairo_save(cr);
cairo_translate(cr, point.x(), point.y());
float red, green, blue, alpha;
context->fillColor().getRGBA(red, green, blue, alpha);
cairo_set_source_rgba(cr, red, green, blue, alpha);
#if PLATFORM(GTK)
gdk_cairo_region(cr, partialRegion);
#else
appendRegionToCairoContext(cr, partialRegion);
#endif
cairo_clip(cr);
pango_cairo_show_layout_line(cr, layoutLine);
if (context->textDrawingMode() & TextModeStroke) {
Color strokeColor = context->strokeColor();
strokeColor.getRGBA(red, green, blue, alpha);
cairo_set_source_rgba(cr, red, green, blue, alpha);
pango_cairo_layout_line_path(cr, layoutLine);
cairo_set_line_width(cr, context->strokeThickness());
cairo_stroke(cr);
}
// Pango sometimes leaves behind paths we don't want
cairo_new_path(cr);
destroyPangoRegion(partialRegion);
g_free(utf8);
g_object_unref(layout);
cairo_restore(cr);
}
SVGTextMetrics::SVGTextMetrics(RenderSVGInlineText* textRenderer, const TextRun& run)
{
ASSERT(textRenderer);
float scalingFactor = textRenderer->scalingFactor();
ASSERT(scalingFactor);
const Font& scaledFont = textRenderer->scaledFont();
int length = 0;
// Calculate width/height using the scaled font, divide this result by the scalingFactor afterwards.
m_width = scaledFont.width(run, length, m_glyph.name) / scalingFactor;
m_height = scaledFont.fontMetrics().floatHeight() / scalingFactor;
m_glyph.unicodeString = run.is8Bit() ? String(run.characters8(), length) : String(run.characters16(), length);
m_glyph.isValid = true;
ASSERT(length >= 0);
m_length = static_cast<unsigned>(length);
}