1/*
2 * (C) 1999 Lars Knoll (knoll@kde.org)
3 * (C) 2000 Dirk Mueller (mueller@kde.org)
4 * Copyright (C) 2004-2017 Apple Inc. All rights reserved.
5 *
6 * This library is free software; you can redistribute it and/or
7 * modify it under the terms of the GNU Library General Public
8 * License as published by the Free Software Foundation; either
9 * version 2 of the License, or (at your option) any later version.
10 *
11 * This library is distributed in the hope that it will be useful,
12 * but WITHOUT ANY WARRANTY; without even the implied warranty of
13 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
14 * Library General Public License for more details.
15 *
16 * You should have received a copy of the GNU Library General Public License
17 * along with this library; see the file COPYING.LIB. If not, write to
18 * the Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor,
19 * Boston, MA 02110-1301, USA.
20 *
21 */
22
23#include "config.h"
24#include "TextPainter.h"
25
26#include "DisplayListReplayer.h"
27#include "FilterOperations.h"
28#include "GraphicsContext.h"
29#include "InlineTextBox.h"
30#include "RenderCombineText.h"
31#include "RenderLayer.h"
32#include "ShadowData.h"
33#include <wtf/NeverDestroyed.h>
34
35namespace WebCore {
36
37ShadowApplier::ShadowApplier(GraphicsContext& context, const ShadowData* shadow, const FilterOperations* colorFilter, const FloatRect& textRect, bool lastShadowIterationShouldDrawText, bool opaque, FontOrientation orientation)
38 : m_context { context }
39 , m_shadow { shadow }
40 , m_onlyDrawsShadow { !isLastShadowIteration() || !lastShadowIterationShouldDrawText }
41 , m_avoidDrawingShadow { shadowIsCompletelyCoveredByText(opaque) }
42 , m_nothingToDraw { shadow && m_avoidDrawingShadow && m_onlyDrawsShadow }
43 , m_didSaveContext { false }
44{
45 if (!shadow || m_nothingToDraw) {
46 m_shadow = nullptr;
47 return;
48 }
49
50 int shadowX = orientation == FontOrientation::Horizontal ? shadow->x() : shadow->y();
51 int shadowY = orientation == FontOrientation::Horizontal ? shadow->y() : -shadow->x();
52 FloatSize shadowOffset(shadowX, shadowY);
53 int shadowRadius = shadow->radius();
54 Color shadowColor = shadow->color();
55 if (colorFilter)
56 colorFilter->transformColor(shadowColor);
57
58 // When drawing shadows, we usually clip the context to the area the shadow will reside, and then
59 // draw the text itself outside the clipped area (so only the shadow shows up). However, we can
60 // often draw the *last* shadow and the text itself in a single call.
61 if (m_onlyDrawsShadow) {
62 FloatRect shadowRect(textRect);
63 shadowRect.inflate(shadow->paintingExtent() + 3 * textRect.height());
64 shadowRect.move(shadowOffset);
65 context.save();
66 context.clip(shadowRect);
67
68 m_didSaveContext = true;
69 m_extraOffset = FloatSize(0, 2 * shadowRect.height() + std::max(0.0f, shadowOffset.height()) + shadowRadius);
70 shadowOffset -= m_extraOffset;
71 }
72
73 if (!m_avoidDrawingShadow)
74 context.setShadow(shadowOffset, shadowRadius, shadowColor);
75}
76
77inline bool ShadowApplier::isLastShadowIteration()
78{
79 return m_shadow && !m_shadow->next();
80}
81
82inline bool ShadowApplier::shadowIsCompletelyCoveredByText(bool textIsOpaque)
83{
84 return textIsOpaque && m_shadow && m_shadow->location().isZero() && !m_shadow->radius();
85}
86
87ShadowApplier::~ShadowApplier()
88{
89 if (!m_shadow)
90 return;
91 if (m_onlyDrawsShadow)
92 m_context.restore();
93 else if (!m_avoidDrawingShadow)
94 m_context.clearShadow();
95}
96
97TextPainter::TextPainter(GraphicsContext& context)
98 : m_context(context)
99{
100}
101
102void TextPainter::paintTextOrEmphasisMarks(const FontCascade& font, const TextRun& textRun, const AtomicString& emphasisMark,
103 float emphasisMarkOffset, const FloatPoint& textOrigin, unsigned startOffset, unsigned endOffset)
104{
105 ASSERT(startOffset < endOffset);
106 if (!emphasisMark.isEmpty())
107 m_context.drawEmphasisMarks(font, textRun, emphasisMark, textOrigin + FloatSize(0, emphasisMarkOffset), startOffset, endOffset);
108 else if (startOffset || endOffset < textRun.length() || !m_glyphDisplayList)
109 m_context.drawText(font, textRun, textOrigin, startOffset, endOffset);
110 else {
111 // Replaying back a whole cached glyph run to the GraphicsContext.
112 m_context.translate(textOrigin);
113 DisplayList::Replayer replayer(m_context, *m_glyphDisplayList);
114 replayer.replay();
115 m_context.translate(-textOrigin);
116 }
117 m_glyphDisplayList = nullptr;
118}
119
120void TextPainter::paintTextWithShadows(const ShadowData* shadow, const FilterOperations* colorFilter, const FontCascade& font, const TextRun& textRun, const FloatRect& boxRect, const FloatPoint& textOrigin,
121 unsigned startOffset, unsigned endOffset, const AtomicString& emphasisMark, float emphasisMarkOffset, bool stroked)
122{
123 if (!shadow) {
124 paintTextOrEmphasisMarks(font, textRun, emphasisMark, emphasisMarkOffset, textOrigin, startOffset, endOffset);
125 return;
126 }
127
128 Color fillColor = m_context.fillColor();
129 bool opaque = fillColor.isOpaque();
130 bool lastShadowIterationShouldDrawText = !stroked && opaque;
131 if (!opaque)
132 m_context.setFillColor(Color::black);
133 while (shadow) {
134 ShadowApplier shadowApplier(m_context, shadow, colorFilter, boxRect, lastShadowIterationShouldDrawText, opaque, m_textBoxIsHorizontal ? FontOrientation::Horizontal : FontOrientation::Vertical);
135 if (!shadowApplier.nothingToDraw())
136 paintTextOrEmphasisMarks(font, textRun, emphasisMark, emphasisMarkOffset, textOrigin + shadowApplier.extraOffset(), startOffset, endOffset);
137 shadow = shadow->next();
138 }
139
140 if (!lastShadowIterationShouldDrawText) {
141 if (!opaque)
142 m_context.setFillColor(fillColor);
143 paintTextOrEmphasisMarks(font, textRun, emphasisMark, emphasisMarkOffset, textOrigin, startOffset, endOffset);
144 }
145}
146
147void TextPainter::paintTextAndEmphasisMarksIfNeeded(const TextRun& textRun, const FloatRect& boxRect, const FloatPoint& textOrigin, unsigned startOffset, unsigned endOffset,
148 const TextPaintStyle& paintStyle, const ShadowData* shadow, const FilterOperations* shadowColorFilter)
149{
150 if (paintStyle.paintOrder == PaintOrder::Normal) {
151 // FIXME: Truncate right-to-left text correctly.
152 paintTextWithShadows(shadow, shadowColorFilter, *m_font, textRun, boxRect, textOrigin, startOffset, endOffset, nullAtom(), 0, paintStyle.strokeWidth > 0);
153 } else {
154 auto textDrawingMode = m_context.textDrawingMode();
155 auto paintOrder = RenderStyle::paintTypesForPaintOrder(paintStyle.paintOrder);
156 auto shadowToUse = shadow;
157
158 for (auto order : paintOrder) {
159 switch (order) {
160 case PaintType::Fill:
161 m_context.setTextDrawingMode(textDrawingMode & ~TextModeStroke);
162 paintTextWithShadows(shadowToUse, shadowColorFilter, *m_font, textRun, boxRect, textOrigin, startOffset, endOffset, nullAtom(), 0, false);
163 shadowToUse = nullptr;
164 m_context.setTextDrawingMode(textDrawingMode);
165 break;
166 case PaintType::Stroke:
167 m_context.setTextDrawingMode(textDrawingMode & ~TextModeFill);
168 paintTextWithShadows(shadowToUse, shadowColorFilter, *m_font, textRun, boxRect, textOrigin, startOffset, endOffset, nullAtom(), 0, paintStyle.strokeWidth > 0);
169 shadowToUse = nullptr;
170 m_context.setTextDrawingMode(textDrawingMode);
171 break;
172 case PaintType::Markers:
173 continue;
174 }
175 }
176 }
177
178 if (m_emphasisMark.isEmpty())
179 return;
180
181 FloatPoint boxOrigin = boxRect.location();
182 updateGraphicsContext(m_context, paintStyle, UseEmphasisMarkColor);
183 static NeverDestroyed<TextRun> objectReplacementCharacterTextRun(StringView(&objectReplacementCharacter, 1));
184 const TextRun& emphasisMarkTextRun = m_combinedText ? objectReplacementCharacterTextRun.get() : textRun;
185 FloatPoint emphasisMarkTextOrigin = m_combinedText ? FloatPoint(boxOrigin.x() + boxRect.width() / 2, boxOrigin.y() + m_font->fontMetrics().ascent()) : textOrigin;
186 if (m_combinedText)
187 m_context.concatCTM(rotation(boxRect, Clockwise));
188
189 // FIXME: Truncate right-to-left text correctly.
190 paintTextWithShadows(shadow, shadowColorFilter, m_combinedText ? m_combinedText->originalFont() : *m_font, emphasisMarkTextRun, boxRect, emphasisMarkTextOrigin, startOffset, endOffset,
191 m_emphasisMark, m_emphasisMarkOffset, paintStyle.strokeWidth > 0);
192
193 if (m_combinedText)
194 m_context.concatCTM(rotation(boxRect, Counterclockwise));
195}
196
197void TextPainter::paint(const TextRun& textRun, const FloatRect& boxRect, const FloatPoint& textOrigin)
198{
199 paintRange(textRun, boxRect, textOrigin, 0, textRun.length());
200}
201
202void TextPainter::paintRange(const TextRun& textRun, const FloatRect& boxRect, const FloatPoint& textOrigin, unsigned start, unsigned end)
203{
204 ASSERT(m_font);
205 ASSERT(start < end);
206
207 GraphicsContextStateSaver stateSaver(m_context, m_style.strokeWidth > 0);
208 updateGraphicsContext(m_context, m_style);
209 paintTextAndEmphasisMarksIfNeeded(textRun, boxRect, textOrigin, start, end, m_style, m_shadow, m_shadowColorFilter);
210}
211
212void TextPainter::clearGlyphDisplayLists()
213{
214 GlyphDisplayListCache<InlineTextBox>::singleton().clear();
215 GlyphDisplayListCache<SimpleLineLayout::Run>::singleton().clear();
216}
217
218bool TextPainter::shouldUseGlyphDisplayList(const PaintInfo& paintInfo)
219{
220 return !paintInfo.context().paintingDisabled() && paintInfo.enclosingSelfPaintingLayer() && paintInfo.enclosingSelfPaintingLayer()->paintingFrequently();
221}
222
223} // namespace WebCore
224