blob: ecdf9354030ff8e27f8b36ee98e4d1afa0d830e9 [file] [log] [blame]
// Copyright 2014 The Chromium Authors. All rights reserved.
// Use of this source code is governed by a BSD-style license that can be
// found in the LICENSE file.
#include "config.h"
#include "core/paint/InlineTextBoxPainter.h"
#include "core/dom/DocumentMarkerController.h"
#include "core/dom/RenderedDocumentMarker.h"
#include "core/editing/CompositionUnderline.h"
#include "core/editing/CompositionUnderlineRangeFilter.h"
#include "core/editing/Editor.h"
#include "core/editing/InputMethodController.h"
#include "core/frame/LocalFrame.h"
#include "core/paint/BoxPainter.h"
#include "core/paint/DrawingRecorder.h"
#include "core/rendering/InlineTextBox.h"
#include "core/rendering/PaintInfo.h"
#include "core/rendering/RenderBlock.h"
#include "core/rendering/RenderCombineText.h"
#include "core/rendering/RenderTheme.h"
#include "core/rendering/TextPainter.h"
namespace blink {
typedef WTF::HashMap<const InlineTextBox*, TextBlobPtr> InlineTextBoxBlobCacheMap;
static InlineTextBoxBlobCacheMap* gTextBlobCache;
static const int misspellingLineThickness = 3;
void InlineTextBoxPainter::removeFromTextBlobCache(InlineTextBox& inlineTextBox)
{
if (gTextBlobCache)
gTextBlobCache->remove(&inlineTextBox);
}
static TextBlobPtr* addToTextBlobCache(InlineTextBox& inlineTextBox)
{
if (!gTextBlobCache)
gTextBlobCache = new InlineTextBoxBlobCacheMap;
return &gTextBlobCache->add(&inlineTextBox, nullptr).storedValue->value;
}
void InlineTextBoxPainter::paint(PaintInfo& paintInfo, const LayoutPoint& paintOffset)
{
if (m_inlineTextBox.isLineBreak() || !paintInfo.shouldPaintWithinRoot(&m_inlineTextBox.renderer()) || m_inlineTextBox.renderer().style()->visibility() != VISIBLE
|| m_inlineTextBox.truncation() == cFullTruncation || paintInfo.phase == PaintPhaseOutline || !m_inlineTextBox.len())
return;
ASSERT(paintInfo.phase != PaintPhaseSelfOutline && paintInfo.phase != PaintPhaseChildOutlines);
LayoutRect logicalVisualOverflow = m_inlineTextBox.logicalOverflowRect();
LayoutUnit logicalStart = logicalVisualOverflow.x() + (m_inlineTextBox.isHorizontal() ? paintOffset.x() : paintOffset.y());
LayoutUnit logicalExtent = logicalVisualOverflow.width();
LayoutUnit paintEnd = m_inlineTextBox.isHorizontal() ? paintInfo.rect.maxX() : paintInfo.rect.maxY();
LayoutUnit paintStart = m_inlineTextBox.isHorizontal() ? paintInfo.rect.x() : paintInfo.rect.y();
// When subpixel font scaling is enabled text runs are positioned at
// subpixel boundaries on the x-axis and thus there is no reason to
// snap the x value. We still round the y-axis to ensure consistent
// line heights.
LayoutPoint adjustedPaintOffset = RuntimeEnabledFeatures::subpixelFontScalingEnabled()
? LayoutPoint(paintOffset.x(), paintOffset.y().round())
: roundedIntPoint(paintOffset);
if (logicalStart >= paintEnd || logicalStart + logicalExtent <= paintStart)
return;
bool isPrinting = m_inlineTextBox.renderer().document().printing();
// Determine whether or not we're selected.
bool haveSelection = !isPrinting && paintInfo.phase != PaintPhaseTextClip && m_inlineTextBox.selectionState() != RenderObject::SelectionNone;
if (!haveSelection && paintInfo.phase == PaintPhaseSelection) {
// When only painting the selection, don't bother to paint if there is none.
return;
}
DrawingRecorder recorder(paintInfo.context, &m_inlineTextBox.renderer(), paintInfo.phase, pixelSnappedIntRect(adjustedPaintOffset, logicalVisualOverflow.size()));
if (m_inlineTextBox.truncation() != cNoTruncation) {
if (m_inlineTextBox.renderer().containingBlock()->style()->isLeftToRightDirection() != m_inlineTextBox.isLeftToRightDirection()) {
// Make the visible fragment of text hug the edge closest to the rest of the run by moving the origin
// at which we start drawing text.
// e.g. In the case of LTR text truncated in an RTL Context, the correct behavior is:
// |Hello|CBA| -> |...He|CBA|
// In order to draw the fragment "He" aligned to the right edge of it's box, we need to start drawing
// farther to the right.
// NOTE: WebKit's behavior differs from that of IE which appears to just overlay the ellipsis on top of the
// truncated string i.e. |Hello|CBA| -> |...lo|CBA|
LayoutUnit widthOfVisibleText = m_inlineTextBox.renderer().width(m_inlineTextBox.start(), m_inlineTextBox.truncation(), m_inlineTextBox.textPos(), m_inlineTextBox.isLeftToRightDirection() ? LTR : RTL, m_inlineTextBox.isFirstLineStyle());
LayoutUnit widthOfHiddenText = m_inlineTextBox.logicalWidth() - widthOfVisibleText;
// FIXME: The hit testing logic also needs to take this translation into account.
LayoutSize truncationOffset(m_inlineTextBox.isLeftToRightDirection() ? widthOfHiddenText : -widthOfHiddenText, 0);
adjustedPaintOffset.move(m_inlineTextBox.isHorizontal() ? truncationOffset : truncationOffset.transposedSize());
}
}
GraphicsContext* context = paintInfo.context;
RenderStyle* styleToUse = m_inlineTextBox.renderer().style(m_inlineTextBox.isFirstLineStyle());
adjustedPaintOffset.move(0, styleToUse->isHorizontalWritingMode() ? 0 : -m_inlineTextBox.logicalHeight());
FloatPoint boxOrigin = m_inlineTextBox.locationIncludingFlipping();
boxOrigin.move(adjustedPaintOffset.x().toFloat(), adjustedPaintOffset.y().toFloat());
FloatRect boxRect(boxOrigin, LayoutSize(m_inlineTextBox.logicalWidth(), m_inlineTextBox.logicalHeight()));
RenderCombineText* combinedText = styleToUse->hasTextCombine() && m_inlineTextBox.renderer().isCombineText() && toRenderCombineText(m_inlineTextBox.renderer()).isCombined() ? &toRenderCombineText(m_inlineTextBox.renderer()) : 0;
bool shouldRotate = !m_inlineTextBox.isHorizontal() && !combinedText;
if (shouldRotate)
context->concatCTM(InlineTextBox::rotation(boxRect, InlineTextBox::Clockwise));
// Determine whether or not we have composition underlines to draw.
bool containsComposition = m_inlineTextBox.renderer().node() && m_inlineTextBox.renderer().frame()->inputMethodController().compositionNode() == m_inlineTextBox.renderer().node();
bool useCustomUnderlines = containsComposition && m_inlineTextBox.renderer().frame()->inputMethodController().compositionUsesCustomUnderlines();
// Determine text colors.
TextPainter::Style textStyle = TextPainter::textPaintingStyle(m_inlineTextBox.renderer(), styleToUse, paintInfo.forceBlackText(), isPrinting);
TextPainter::Style selectionStyle = TextPainter::selectionPaintingStyle(m_inlineTextBox.renderer(), haveSelection, paintInfo.forceBlackText(), isPrinting, textStyle);
bool paintSelectedTextOnly = (paintInfo.phase == PaintPhaseSelection);
bool paintSelectedTextSeparately = !paintSelectedTextOnly && textStyle != selectionStyle;
// Set our font.
const Font& font = styleToUse->font();
FloatPoint textOrigin = FloatPoint(boxOrigin.x(), boxOrigin.y() + font.fontMetrics().ascent());
if (combinedText)
combinedText->adjustTextOrigin(textOrigin, boxRect);
// 1. Paint backgrounds behind text if needed. Examples of such backgrounds include selection
// and composition highlights.
if (paintInfo.phase != PaintPhaseSelection && paintInfo.phase != PaintPhaseTextClip && !isPrinting) {
if (containsComposition) {
paintCompositionBackgrounds(context, boxOrigin, styleToUse, font, useCustomUnderlines);
}
paintDocumentMarkers(context, boxOrigin, styleToUse, font, true);
if (haveSelection && !useCustomUnderlines)
paintSelection(context, boxOrigin, styleToUse, font, selectionStyle.fillColor);
}
// 2. Now paint the foreground, including text and decorations like underline/overline (in quirks mode only).
int length = m_inlineTextBox.len();
int maximumLength;
StringView string;
if (!combinedText) {
string = m_inlineTextBox.renderer().text().createView();
if (static_cast<unsigned>(length) != string.length() || m_inlineTextBox.start())
string.narrow(m_inlineTextBox.start(), length);
maximumLength = m_inlineTextBox.renderer().textLength() - m_inlineTextBox.start();
} else {
combinedText->getStringToRender(m_inlineTextBox.start(), string, length);
maximumLength = length;
}
StringBuilder charactersWithHyphen;
TextRun textRun = m_inlineTextBox.constructTextRun(styleToUse, font, string, maximumLength, m_inlineTextBox.hasHyphen() ? &charactersWithHyphen : 0);
if (m_inlineTextBox.hasHyphen())
length = textRun.length();
int selectionStart = 0;
int selectionEnd = 0;
if (paintSelectedTextOnly || paintSelectedTextSeparately)
m_inlineTextBox.selectionStartEnd(selectionStart, selectionEnd);
bool respectHyphen = selectionEnd == static_cast<int>(m_inlineTextBox.len()) && m_inlineTextBox.hasHyphen();
if (respectHyphen)
selectionEnd = textRun.length();
if (m_inlineTextBox.truncation() != cNoTruncation) {
selectionStart = std::min<int>(selectionStart, m_inlineTextBox.truncation());
selectionEnd = std::min<int>(selectionEnd, m_inlineTextBox.truncation());
length = m_inlineTextBox.truncation();
}
TextPainter textPainter(context, font, textRun, textOrigin, boxRect, m_inlineTextBox.isHorizontal());
TextEmphasisPosition emphasisMarkPosition;
bool hasTextEmphasis = m_inlineTextBox.getEmphasisMarkPosition(styleToUse, emphasisMarkPosition);
if (hasTextEmphasis)
textPainter.setEmphasisMark(styleToUse->textEmphasisMarkString(), emphasisMarkPosition);
if (combinedText)
textPainter.setCombinedText(combinedText);
if (!paintSelectedTextOnly) {
// FIXME: Truncate right-to-left text correctly.
int startOffset = 0;
int endOffset = length;
if (paintSelectedTextSeparately && selectionStart < selectionEnd) {
startOffset = selectionEnd;
endOffset = selectionStart;
}
// FIXME: This cache should probably ultimately be held somewhere else.
// A hashmap is convenient to avoid a memory hit when the
// RuntimeEnabledFeature is off.
bool textBlobIsCacheable = RuntimeEnabledFeatures::textBlobEnabled() && startOffset == 0 && endOffset == length;
TextBlobPtr* cachedTextBlob = 0;
if (textBlobIsCacheable)
cachedTextBlob = addToTextBlobCache(m_inlineTextBox);
textPainter.paint(startOffset, endOffset, length, textStyle, cachedTextBlob);
}
if ((paintSelectedTextOnly || paintSelectedTextSeparately) && selectionStart < selectionEnd) {
// paint only the text that is selected
bool textBlobIsCacheable = RuntimeEnabledFeatures::textBlobEnabled() && selectionStart == 0 && selectionEnd == length;
TextBlobPtr* cachedTextBlob = 0;
if (textBlobIsCacheable)
cachedTextBlob = addToTextBlobCache(m_inlineTextBox);
textPainter.paint(selectionStart, selectionEnd, length, selectionStyle, cachedTextBlob);
}
// Paint decorations
TextDecoration textDecorations = styleToUse->textDecorationsInEffect();
if (textDecorations != TextDecorationNone && !paintSelectedTextOnly) {
GraphicsContextStateSaver stateSaver(*context, false);
TextPainter::updateGraphicsContext(context, textStyle, m_inlineTextBox.isHorizontal(), stateSaver);
if (combinedText)
context->concatCTM(InlineTextBox::rotation(boxRect, InlineTextBox::Clockwise));
paintDecoration(context, boxOrigin, textDecorations);
if (combinedText)
context->concatCTM(InlineTextBox::rotation(boxRect, InlineTextBox::Counterclockwise));
}
if (paintInfo.phase == PaintPhaseForeground) {
paintDocumentMarkers(context, boxOrigin, styleToUse, font, false);
// Paint custom underlines for compositions.
if (useCustomUnderlines) {
const Vector<CompositionUnderline>& underlines = m_inlineTextBox.renderer().frame()->inputMethodController().customCompositionUnderlines();
CompositionUnderlineRangeFilter filter(underlines, m_inlineTextBox.start(), m_inlineTextBox.end());
for (CompositionUnderlineRangeFilter::ConstIterator it = filter.begin(); it != filter.end(); ++it) {
if (it->color == Color::transparent)
continue;
paintCompositionUnderline(context, boxOrigin, *it);
}
}
}
if (shouldRotate)
context->concatCTM(InlineTextBox::rotation(boxRect, InlineTextBox::Counterclockwise));
}
unsigned InlineTextBoxPainter::underlinePaintStart(const CompositionUnderline& underline)
{
return std::max(static_cast<unsigned>(m_inlineTextBox.start()), underline.startOffset);
}
unsigned InlineTextBoxPainter::underlinePaintEnd(const CompositionUnderline& underline)
{
unsigned paintEnd = std::min(m_inlineTextBox.end() + 1, underline.endOffset); // end() points at the last char, not past it.
if (m_inlineTextBox.truncation() != cNoTruncation)
paintEnd = std::min(paintEnd, static_cast<unsigned>(m_inlineTextBox.start() + m_inlineTextBox.truncation()));
return paintEnd;
}
void InlineTextBoxPainter::paintCompositionBackgrounds(GraphicsContext* pt, const FloatPoint& boxOrigin, RenderStyle* style, const Font& font, bool useCustomUnderlines)
{
if (useCustomUnderlines) {
// Paint custom background highlights for compositions.
const Vector<CompositionUnderline>& underlines = m_inlineTextBox.renderer().frame()->inputMethodController().customCompositionUnderlines();
CompositionUnderlineRangeFilter filter(underlines, m_inlineTextBox.start(), m_inlineTextBox.end());
for (CompositionUnderlineRangeFilter::ConstIterator it = filter.begin(); it != filter.end(); ++it) {
if (it->backgroundColor == Color::transparent)
continue;
paintSingleCompositionBackgroundRun(pt, boxOrigin, style, font, it->backgroundColor, underlinePaintStart(*it), underlinePaintEnd(*it));
}
} else {
paintSingleCompositionBackgroundRun(pt, boxOrigin, style, font, RenderTheme::theme().platformDefaultCompositionBackgroundColor(),
m_inlineTextBox.renderer().frame()->inputMethodController().compositionStart(),
m_inlineTextBox.renderer().frame()->inputMethodController().compositionEnd());
}
}
void InlineTextBoxPainter::paintSingleCompositionBackgroundRun(GraphicsContext* context, const FloatPoint& boxOrigin, RenderStyle* style, const Font& font, Color backgroundColor, int startPos, int endPos)
{
int sPos = std::max(startPos - static_cast<int>(m_inlineTextBox.start()), 0);
int ePos = std::min(endPos - static_cast<int>(m_inlineTextBox.start()), static_cast<int>(m_inlineTextBox.len()));
if (sPos >= ePos)
return;
int deltaY = m_inlineTextBox.renderer().style()->isFlippedLinesWritingMode() ? m_inlineTextBox.root().selectionBottom() - m_inlineTextBox.logicalBottom() : m_inlineTextBox.logicalTop() - m_inlineTextBox.root().selectionTop();
int selHeight = m_inlineTextBox.root().selectionHeight();
FloatPoint localOrigin(boxOrigin.x(), boxOrigin.y() - deltaY);
context->drawHighlightForText(font, m_inlineTextBox.constructTextRun(style, font), localOrigin, selHeight, backgroundColor, sPos, ePos);
}
void InlineTextBoxPainter::paintDocumentMarkers(GraphicsContext* pt, const FloatPoint& boxOrigin, RenderStyle* style, const Font& font, bool background)
{
if (!m_inlineTextBox.renderer().node())
return;
DocumentMarkerVector markers = m_inlineTextBox.renderer().document().markers().markersFor(m_inlineTextBox.renderer().node());
DocumentMarkerVector::const_iterator markerIt = markers.begin();
// Give any document markers that touch this run a chance to draw before the text has been drawn.
// Note end() points at the last char, not one past it like endOffset and ranges do.
for ( ; markerIt != markers.end(); ++markerIt) {
DocumentMarker* marker = *markerIt;
// Paint either the background markers or the foreground markers, but not both
switch (marker->type()) {
case DocumentMarker::Grammar:
case DocumentMarker::Spelling:
if (background)
continue;
break;
case DocumentMarker::TextMatch:
if (!background)
continue;
break;
default:
continue;
}
if (marker->endOffset() <= m_inlineTextBox.start()) {
// marker is completely before this run. This might be a marker that sits before the
// first run we draw, or markers that were within runs we skipped due to truncation.
continue;
}
if (marker->startOffset() > m_inlineTextBox.end()) {
// marker is completely after this run, bail. A later run will paint it.
break;
}
// marker intersects this run. Paint it.
switch (marker->type()) {
case DocumentMarker::Spelling:
m_inlineTextBox.paintDocumentMarker(pt, boxOrigin, marker, style, font, false);
break;
case DocumentMarker::Grammar:
m_inlineTextBox.paintDocumentMarker(pt, boxOrigin, marker, style, font, true);
break;
case DocumentMarker::TextMatch:
m_inlineTextBox.paintTextMatchMarker(pt, boxOrigin, marker, style, font);
break;
default:
ASSERT_NOT_REACHED();
}
}
}
static GraphicsContext::DocumentMarkerLineStyle lineStyleForMarkerType(DocumentMarker::MarkerType markerType)
{
switch (markerType) {
case DocumentMarker::Spelling:
return GraphicsContext::DocumentMarkerSpellingLineStyle;
case DocumentMarker::Grammar:
return GraphicsContext::DocumentMarkerGrammarLineStyle;
default:
ASSERT_NOT_REACHED();
return GraphicsContext::DocumentMarkerSpellingLineStyle;
}
}
void InlineTextBoxPainter::paintDocumentMarker(GraphicsContext* pt, const FloatPoint& boxOrigin, DocumentMarker* marker, RenderStyle* style, const Font& font, bool grammar)
{
// Never print spelling/grammar markers (5327887)
if (m_inlineTextBox.renderer().document().printing())
return;
if (m_inlineTextBox.truncation() == cFullTruncation)
return;
float start = 0; // start of line to draw, relative to tx
float width = m_inlineTextBox.logicalWidth(); // how much line to draw
// Determine whether we need to measure text
bool markerSpansWholeBox = true;
if (m_inlineTextBox.start() <= marker->startOffset())
markerSpansWholeBox = false;
if ((m_inlineTextBox.end() + 1) != marker->endOffset()) // end points at the last char, not past it
markerSpansWholeBox = false;
if (m_inlineTextBox.truncation() != cNoTruncation)
markerSpansWholeBox = false;
if (!markerSpansWholeBox || grammar) {
int startPosition = std::max<int>(marker->startOffset() - m_inlineTextBox.start(), 0);
int endPosition = std::min<int>(marker->endOffset() - static_cast<int>(m_inlineTextBox.start()), m_inlineTextBox.len());
if (m_inlineTextBox.truncation() != cNoTruncation)
endPosition = std::min<int>(endPosition, m_inlineTextBox.truncation());
// Calculate start & width
int deltaY = m_inlineTextBox.renderer().style()->isFlippedLinesWritingMode() ? m_inlineTextBox.root().selectionBottom() - m_inlineTextBox.logicalBottom() : m_inlineTextBox.logicalTop() - m_inlineTextBox.root().selectionTop();
int selHeight = m_inlineTextBox.root().selectionHeight();
FloatPoint startPoint(boxOrigin.x(), boxOrigin.y() - deltaY);
TextRun run = m_inlineTextBox.constructTextRun(style, font);
// FIXME: Convert the document markers to float rects.
IntRect markerRect = enclosingIntRect(font.selectionRectForText(run, startPoint, selHeight, startPosition, endPosition));
start = markerRect.x() - startPoint.x();
width = markerRect.width();
// Store rendered rects for bad grammar markers, so we can hit-test against it elsewhere in order to
// display a toolTip. We don't do this for misspelling markers.
if (grammar) {
markerRect.move(-boxOrigin.x(), -boxOrigin.y());
markerRect = m_inlineTextBox.renderer().localToAbsoluteQuad(FloatRect(markerRect)).enclosingBoundingBox();
toRenderedDocumentMarker(marker)->setRenderedRect(markerRect);
}
}
// IMPORTANT: The misspelling underline is not considered when calculating the text bounds, so we have to
// make sure to fit within those bounds. This means the top pixel(s) of the underline will overlap the
// bottom pixel(s) of the glyphs in smaller font sizes. The alternatives are to increase the line spacing (bad!!)
// or decrease the underline thickness. The overlap is actually the most useful, and matches what AppKit does.
// So, we generally place the underline at the bottom of the text, but in larger fonts that's not so good so
// we pin to two pixels under the baseline.
int lineThickness = misspellingLineThickness;
int baseline = m_inlineTextBox.renderer().style(m_inlineTextBox.isFirstLineStyle())->fontMetrics().ascent();
int descent = m_inlineTextBox.logicalHeight() - baseline;
int underlineOffset;
if (descent <= (2 + lineThickness)) {
// Place the underline at the very bottom of the text in small/medium fonts.
underlineOffset = m_inlineTextBox.logicalHeight() - lineThickness;
} else {
// In larger fonts, though, place the underline up near the baseline to prevent a big gap.
underlineOffset = baseline + 2;
}
pt->drawLineForDocumentMarker(FloatPoint(boxOrigin.x() + start, boxOrigin.y() + underlineOffset), width, lineStyleForMarkerType(marker->type()));
}
void InlineTextBoxPainter::paintSelection(GraphicsContext* context, const FloatPoint& boxOrigin, RenderStyle* style, const Font& font, Color textColor)
{
// See if we have a selection to paint at all.
int sPos, ePos;
m_inlineTextBox.selectionStartEnd(sPos, ePos);
if (sPos >= ePos)
return;
Color c = m_inlineTextBox.renderer().selectionBackgroundColor();
if (!c.alpha())
return;
// If the text color ends up being the same as the selection background, invert the selection
// background.
if (textColor == c)
c = Color(0xff - c.red(), 0xff - c.green(), 0xff - c.blue());
// If the text is truncated, let the thing being painted in the truncation
// draw its own highlight.
int length = m_inlineTextBox.truncation() != cNoTruncation ? m_inlineTextBox.truncation() : m_inlineTextBox.len();
StringView string = m_inlineTextBox.renderer().text().createView();
if (string.length() != static_cast<unsigned>(length) || m_inlineTextBox.start())
string.narrow(m_inlineTextBox.start(), length);
StringBuilder charactersWithHyphen;
bool respectHyphen = ePos == length && m_inlineTextBox.hasHyphen();
TextRun textRun = m_inlineTextBox.constructTextRun(style, font, string, m_inlineTextBox.renderer().textLength() - m_inlineTextBox.start(), respectHyphen ? &charactersWithHyphen : 0);
if (respectHyphen)
ePos = textRun.length();
LayoutUnit selectionBottom = m_inlineTextBox.root().selectionBottom();
LayoutUnit selectionTop = m_inlineTextBox.root().selectionTopAdjustedForPrecedingBlock();
int deltaY = roundToInt(m_inlineTextBox.renderer().style()->isFlippedLinesWritingMode() ? selectionBottom - m_inlineTextBox.logicalBottom() : m_inlineTextBox.logicalTop() - selectionTop);
int selHeight = std::max(0, roundToInt(selectionBottom - selectionTop));
FloatPoint localOrigin(boxOrigin.x(), boxOrigin.y() - deltaY);
FloatRect clipRect(localOrigin, FloatSize(m_inlineTextBox.logicalWidth(), selHeight));
GraphicsContextStateSaver stateSaver(*context);
context->clip(clipRect);
context->drawHighlightForText(font, textRun, localOrigin, selHeight, c, sPos, ePos);
}
static int computeUnderlineOffset(const TextUnderlinePosition underlinePosition, const FontMetrics& fontMetrics, const InlineTextBox* inlineTextBox, const float textDecorationThickness)
{
// Compute the gap between the font and the underline. Use at least one
// pixel gap, if underline is thick then use a bigger gap.
int gap = 0;
// Underline position of zero means draw underline on Baseline Position,
// in Blink we need at least 1-pixel gap to adding following check.
// Positive underline Position means underline should be drawn above baselin e
// and negative value means drawing below baseline, negating the value as in Blink
// downward Y-increases.
if (fontMetrics.underlinePosition())
gap = -fontMetrics.underlinePosition();
else
gap = std::max<int>(1, ceilf(textDecorationThickness / 2.f));
// FIXME: We support only horizontal text for now.
switch (underlinePosition) {
case TextUnderlinePositionAuto:
return fontMetrics.ascent() + gap; // Position underline near the alphabetic baseline.
case TextUnderlinePositionUnder: {
// Position underline relative to the under edge of the lowest element's content box.
const float offset = inlineTextBox->root().maxLogicalTop() - inlineTextBox->logicalTop();
if (offset > 0)
return inlineTextBox->logicalHeight() + gap + offset;
return inlineTextBox->logicalHeight() + gap;
}
}
ASSERT_NOT_REACHED();
return fontMetrics.ascent() + gap;
}
static bool shouldSetDecorationAntialias(TextDecorationStyle decorationStyle)
{
return decorationStyle == TextDecorationStyleDotted || decorationStyle == TextDecorationStyleDashed;
}
static bool shouldSetDecorationAntialias(TextDecorationStyle underline, TextDecorationStyle overline, TextDecorationStyle linethrough)
{
return shouldSetDecorationAntialias(underline) || shouldSetDecorationAntialias(overline) || shouldSetDecorationAntialias(linethrough);
}
static StrokeStyle textDecorationStyleToStrokeStyle(TextDecorationStyle decorationStyle)
{
StrokeStyle strokeStyle = SolidStroke;
switch (decorationStyle) {
case TextDecorationStyleSolid:
strokeStyle = SolidStroke;
break;
case TextDecorationStyleDouble:
strokeStyle = DoubleStroke;
break;
case TextDecorationStyleDotted:
strokeStyle = DottedStroke;
break;
case TextDecorationStyleDashed:
strokeStyle = DashedStroke;
break;
case TextDecorationStyleWavy:
strokeStyle = WavyStroke;
break;
}
return strokeStyle;
}
static void adjustStepToDecorationLength(float& step, float& controlPointDistance, float length)
{
ASSERT(step > 0);
if (length <= 0)
return;
unsigned stepCount = static_cast<unsigned>(length / step);
// Each Bezier curve starts at the same pixel that the previous one
// ended. We need to subtract (stepCount - 1) pixels when calculating the
// length covered to account for that.
float uncoveredLength = length - (stepCount * step - (stepCount - 1));
float adjustment = uncoveredLength / stepCount;
step += adjustment;
controlPointDistance += adjustment;
}
/*
* Draw one cubic Bezier curve and repeat the same pattern long the the decoration's axis.
* The start point (p1), controlPoint1, controlPoint2 and end point (p2) of the Bezier curve
* form a diamond shape:
*
* step
* |-----------|
*
* controlPoint1
* +
*
*
* . .
* . .
* . .
* (x1, y1) p1 + . + p2 (x2, y2) - <--- Decoration's axis
* . . |
* . . |
* . . | controlPointDistance
* |
* |
* + -
* controlPoint2
*
* |-----------|
* step
*/
static void strokeWavyTextDecoration(GraphicsContext* context, FloatPoint p1, FloatPoint p2, float strokeThickness)
{
context->adjustLineToPixelBoundaries(p1, p2, strokeThickness, context->strokeStyle());
Path path;
path.moveTo(p1);
// Distance between decoration's axis and Bezier curve's control points.
// The height of the curve is based on this distance. Use a minimum of 6 pixels distance since
// the actual curve passes approximately at half of that distance, that is 3 pixels.
// The minimum height of the curve is also approximately 3 pixels. Increases the curve's height
// as strockThickness increases to make the curve looks better.
float controlPointDistance = 3 * std::max<float>(2, strokeThickness);
// Increment used to form the diamond shape between start point (p1), control
// points and end point (p2) along the axis of the decoration. Makes the
// curve wider as strockThickness increases to make the curve looks better.
float step = 2 * std::max<float>(2, strokeThickness);
bool isVerticalLine = (p1.x() == p2.x());
if (isVerticalLine) {
ASSERT(p1.x() == p2.x());
float xAxis = p1.x();
float y1;
float y2;
if (p1.y() < p2.y()) {
y1 = p1.y();
y2 = p2.y();
} else {
y1 = p2.y();
y2 = p1.y();
}
adjustStepToDecorationLength(step, controlPointDistance, y2 - y1);
FloatPoint controlPoint1(xAxis + controlPointDistance, 0);
FloatPoint controlPoint2(xAxis - controlPointDistance, 0);
for (float y = y1; y + 2 * step <= y2;) {
controlPoint1.setY(y + step);
controlPoint2.setY(y + step);
y += 2 * step;
path.addBezierCurveTo(controlPoint1, controlPoint2, FloatPoint(xAxis, y));
}
} else {
ASSERT(p1.y() == p2.y());
float yAxis = p1.y();
float x1;
float x2;
if (p1.x() < p2.x()) {
x1 = p1.x();
x2 = p2.x();
} else {
x1 = p2.x();
x2 = p1.x();
}
adjustStepToDecorationLength(step, controlPointDistance, x2 - x1);
FloatPoint controlPoint1(0, yAxis + controlPointDistance);
FloatPoint controlPoint2(0, yAxis - controlPointDistance);
for (float x = x1; x + 2 * step <= x2;) {
controlPoint1.setX(x + step);
controlPoint2.setX(x + step);
x += 2 * step;
path.addBezierCurveTo(controlPoint1, controlPoint2, FloatPoint(x, yAxis));
}
}
context->setShouldAntialias(true);
context->strokePath(path);
}
static void paintAppliedDecoration(GraphicsContext* context, FloatPoint start, float width, float doubleOffset, int wavyOffsetFactor,
RenderObject::AppliedTextDecoration decoration, float thickness, bool antialiasDecoration, bool isPrinting)
{
context->setStrokeStyle(textDecorationStyleToStrokeStyle(decoration.style));
context->setStrokeColor(decoration.color);
switch (decoration.style) {
case TextDecorationStyleWavy:
strokeWavyTextDecoration(context, start + FloatPoint(0, doubleOffset * wavyOffsetFactor), start + FloatPoint(width, doubleOffset * wavyOffsetFactor), thickness);
break;
case TextDecorationStyleDotted:
case TextDecorationStyleDashed:
context->setShouldAntialias(antialiasDecoration);
// Fall through
default:
context->drawLineForText(start, width, isPrinting);
if (decoration.style == TextDecorationStyleDouble)
context->drawLineForText(start + FloatPoint(0, doubleOffset), width, isPrinting);
}
}
void InlineTextBoxPainter::paintDecoration(GraphicsContext* context, const FloatPoint& boxOrigin, TextDecoration deco)
{
GraphicsContextStateSaver stateSaver(*context);
if (m_inlineTextBox.truncation() == cFullTruncation)
return;
FloatPoint localOrigin = boxOrigin;
float width = m_inlineTextBox.logicalWidth();
if (m_inlineTextBox.truncation() != cNoTruncation) {
width = m_inlineTextBox.renderer().width(m_inlineTextBox.start(), m_inlineTextBox.truncation(), m_inlineTextBox.textPos(), m_inlineTextBox.isLeftToRightDirection() ? LTR : RTL, m_inlineTextBox.isFirstLineStyle());
if (!m_inlineTextBox.isLeftToRightDirection())
localOrigin.move(m_inlineTextBox.logicalWidth() - width, 0);
}
// Get the text decoration colors.
RenderObject::AppliedTextDecoration underline, overline, linethrough;
m_inlineTextBox.renderer().getTextDecorations(deco, underline, overline, linethrough, true);
if (m_inlineTextBox.isFirstLineStyle())
m_inlineTextBox.renderer().getTextDecorations(deco, underline, overline, linethrough, true, true);
// Use a special function for underlines to get the positioning exactly right.
bool isPrinting = m_inlineTextBox.renderer().document().printing();
RenderStyle* styleToUse = m_inlineTextBox.renderer().style(m_inlineTextBox.isFirstLineStyle());
int baseline = styleToUse->fontMetrics().ascent();
// Set the thick of the line to be 10% (or something else ?)of the computed font size and not less than 1px.
// Using computedFontSize should take care of zoom as well.
// Update Underline thickness, in case we have Faulty Font Metrics calculating underline thickness by old method.
float textDecorationThickness = styleToUse->fontMetrics().underlineThickness();
int fontHeightInt = (int)(styleToUse->fontMetrics().floatHeight() + 0.5);
if ((textDecorationThickness == 0.f) || (textDecorationThickness >= (fontHeightInt >> 1)))
textDecorationThickness = std::max(1.f, styleToUse->computedFontSize() / 10.f);
context->setStrokeThickness(textDecorationThickness);
bool antialiasDecoration = shouldSetDecorationAntialias(overline.style, underline.style, linethrough.style)
&& BoxPainter::shouldAntialiasLines(context);
// Offset between lines - always non-zero, so lines never cross each other.
float doubleOffset = textDecorationThickness + 1.f;
if (deco & TextDecorationUnderline) {
const int underlineOffset = computeUnderlineOffset(styleToUse->textUnderlinePosition(), styleToUse->fontMetrics(), &m_inlineTextBox, textDecorationThickness);
paintAppliedDecoration(context, localOrigin + FloatPoint(0, underlineOffset), width, doubleOffset, 1, underline, textDecorationThickness, antialiasDecoration, isPrinting);
}
if (deco & TextDecorationOverline) {
paintAppliedDecoration(context, localOrigin, width, -doubleOffset, 1, overline, textDecorationThickness, antialiasDecoration, isPrinting);
}
if (deco & TextDecorationLineThrough) {
const float lineThroughOffset = 2 * baseline / 3;
paintAppliedDecoration(context, localOrigin + FloatPoint(0, lineThroughOffset), width, doubleOffset, 0, linethrough, textDecorationThickness, antialiasDecoration, isPrinting);
}
}
void InlineTextBoxPainter::paintCompositionUnderline(GraphicsContext* ctx, const FloatPoint& boxOrigin, const CompositionUnderline& underline)
{
if (m_inlineTextBox.truncation() == cFullTruncation)
return;
unsigned paintStart = underlinePaintStart(underline);
unsigned paintEnd = underlinePaintEnd(underline);
// start of line to draw, relative to paintOffset.
float start = paintStart == static_cast<unsigned>(m_inlineTextBox.start()) ? 0 :
m_inlineTextBox.renderer().width(m_inlineTextBox.start(), paintStart - m_inlineTextBox.start(), m_inlineTextBox.textPos(), m_inlineTextBox.isLeftToRightDirection() ? LTR : RTL, m_inlineTextBox.isFirstLineStyle());
// how much line to draw
float width = (paintStart == static_cast<unsigned>(m_inlineTextBox.start()) && paintEnd == static_cast<unsigned>(m_inlineTextBox.end()) + 1) ? m_inlineTextBox.logicalWidth() :
m_inlineTextBox.renderer().width(paintStart, paintEnd - paintStart, m_inlineTextBox.textPos() + start, m_inlineTextBox.isLeftToRightDirection() ? LTR : RTL, m_inlineTextBox.isFirstLineStyle());
// Thick marked text underlines are 2px thick as long as there is room for the 2px line under the baseline.
// All other marked text underlines are 1px thick.
// If there's not enough space the underline will touch or overlap characters.
int lineThickness = 1;
int baseline = m_inlineTextBox.renderer().style(m_inlineTextBox.isFirstLineStyle())->fontMetrics().ascent();
if (underline.thick && m_inlineTextBox.logicalHeight() - baseline >= 2)
lineThickness = 2;
// We need to have some space between underlines of subsequent clauses, because some input methods do not use different underline styles for those.
// We make each line shorter, which has a harmless side effect of shortening the first and last clauses, too.
start += 1;
width -= 2;
ctx->setStrokeColor(underline.color);
ctx->setStrokeThickness(lineThickness);
ctx->drawLineForText(FloatPoint(boxOrigin.x() + start, boxOrigin.y() + m_inlineTextBox.logicalHeight() - lineThickness), width, m_inlineTextBox.renderer().document().printing());
}
void InlineTextBoxPainter::paintTextMatchMarker(GraphicsContext* pt, const FloatPoint& boxOrigin, DocumentMarker* marker, RenderStyle* style, const Font& font)
{
// Use same y positioning and height as for selection, so that when the selection and this highlight are on
// the same word there are no pieces sticking out.
int deltaY = m_inlineTextBox.renderer().style()->isFlippedLinesWritingMode() ? m_inlineTextBox.root().selectionBottom() - m_inlineTextBox.logicalBottom() : m_inlineTextBox.logicalTop() - m_inlineTextBox.root().selectionTop();
int selHeight = m_inlineTextBox.root().selectionHeight();
int sPos = std::max(marker->startOffset() - m_inlineTextBox.start(), (unsigned)0);
int ePos = std::min(marker->endOffset() - m_inlineTextBox.start(), m_inlineTextBox.len());
TextRun run = m_inlineTextBox.constructTextRun(style, font);
// Always compute and store the rect associated with this marker. The computed rect is in absolute coordinates.
IntRect markerRect = enclosingIntRect(font.selectionRectForText(run, IntPoint(m_inlineTextBox.x(), m_inlineTextBox.root().selectionTop()), selHeight, sPos, ePos));
markerRect = m_inlineTextBox.renderer().localToAbsoluteQuad(FloatRect(markerRect)).enclosingBoundingBox();
toRenderedDocumentMarker(marker)->setRenderedRect(markerRect);
// Optionally highlight the text
if (m_inlineTextBox.renderer().frame()->editor().markedTextMatchesAreHighlighted()) {
Color color = marker->activeMatch() ?
RenderTheme::theme().platformActiveTextSearchHighlightColor() :
RenderTheme::theme().platformInactiveTextSearchHighlightColor();
GraphicsContextStateSaver stateSaver(*pt);
pt->clip(FloatRect(boxOrigin.x(), boxOrigin.y() - deltaY, m_inlineTextBox.logicalWidth(), selHeight));
pt->drawHighlightForText(font, run, FloatPoint(boxOrigin.x(), boxOrigin.y() - deltaY), selHeight, color, sPos, ePos);
}
}
} // namespace blink