1/*
2 * (C) 1999 Lars Knoll (knoll@kde.org)
3 * (C) 2000 Dirk Mueller (mueller@kde.org)
4 * Copyright (C) 2004, 2005, 2006, 2007, 2008, 2009, 2010, 2011, 2012, 2013 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 "GraphicsContext.h"
27#include "InlineTextBox.h"
28#include "RenderCombineText.h"
29#include "TextPaintStyle.h"
30
31namespace WebCore {
32
33TextPainter::TextPainter(GraphicsContext& context, bool paintSelectedTextOnly, bool paintSelectedTextSeparately, const Font& font,
34    int startPositionInTextRun, int endPositionInTextBoxString, int length, const AtomicString& emphasisMark, RenderCombineText* combinedText, TextRun& textRun,
35    FloatRect& boxRect, FloatPoint& textOrigin, int emphasisMarkOffset, const ShadowData* textShadow, const ShadowData* selectionShadow,
36    bool textBoxIsHorizontal, TextPaintStyle& textPaintStyle, TextPaintStyle& selectionPaintStyle)
37    : m_paintSelectedTextOnly(paintSelectedTextOnly)
38    , m_paintSelectedTextSeparately(paintSelectedTextSeparately)
39    , m_font(font)
40    , m_startPositionInTextRun(startPositionInTextRun)
41    , m_endPositionInTextRun(endPositionInTextBoxString)
42    , m_length(length)
43    , m_emphasisMark(emphasisMark)
44    , m_combinedText(combinedText)
45    , m_textRun(textRun)
46    , m_boxRect(boxRect)
47    , m_textOrigin(textOrigin)
48    , m_emphasisMarkOffset(emphasisMarkOffset)
49    , m_textBoxIsHorizontal(textBoxIsHorizontal)
50    , m_savedDrawingStateForMask(&context, &textPaintStyle, &selectionPaintStyle, textShadow, selectionShadow)
51{
52}
53
54static void drawTextOrEmphasisMarks(GraphicsContext& context, const Font& font, const TextRun& textRun, const AtomicString& emphasisMark,
55    int emphasisMarkOffset, const FloatPoint& point, const int from, const int to)
56{
57    if (emphasisMark.isEmpty())
58        context.drawText(font, textRun, point, from, to);
59    else
60        context.drawEmphasisMarks(font, textRun, emphasisMark, point + IntSize(0, emphasisMarkOffset), from, to);
61}
62
63static void paintTextWithShadows(GraphicsContext* context, const Font& font, const TextRun& textRun, const AtomicString& emphasisMark,
64    int emphasisMarkOffset, int startOffset, int endOffset, int truncationPoint, const FloatPoint& textOrigin, const FloatRect& boxRect,
65    const ShadowData* shadow, bool stroked, bool horizontal)
66{
67    Color fillColor = context->fillColor();
68    ColorSpace fillColorSpace = context->fillColorSpace();
69    bool opaque = !fillColor.hasAlpha();
70    if (!opaque)
71        context->setFillColor(Color::black, fillColorSpace);
72
73    do {
74        IntSize extraOffset;
75        if (shadow)
76            extraOffset = roundedIntSize(InlineTextBox::applyShadowToGraphicsContext(context, shadow, boxRect, stroked, opaque, horizontal));
77        else if (!opaque)
78            context->setFillColor(fillColor, fillColorSpace);
79
80        if (startOffset <= endOffset)
81            drawTextOrEmphasisMarks(*context, font, textRun, emphasisMark, emphasisMarkOffset, textOrigin + extraOffset, startOffset, endOffset);
82        else {
83            if (endOffset > 0)
84                drawTextOrEmphasisMarks(*context, font, textRun, emphasisMark, emphasisMarkOffset, textOrigin + extraOffset, 0, endOffset);
85            if (startOffset < truncationPoint)
86                drawTextOrEmphasisMarks(*context, font, textRun, emphasisMark, emphasisMarkOffset, textOrigin + extraOffset, startOffset, truncationPoint);
87        }
88
89        if (!shadow)
90            break;
91
92        if (shadow->next() || stroked || !opaque)
93            context->restore();
94        else
95            context->clearShadow();
96
97        shadow = shadow->next();
98    } while (shadow || stroked || !opaque);
99}
100
101void TextPainter::paintText()
102{
103    ASSERT(m_savedDrawingStateForMask.m_textPaintStyle);
104    ASSERT(m_savedDrawingStateForMask.m_selectionPaintStyle);
105
106    FloatPoint boxOrigin = m_boxRect.location();
107
108    if (!m_paintSelectedTextOnly) {
109        // For stroked painting, we have to change the text drawing mode. It's probably dangerous to leave that mutated as a side
110        // effect, so only when we know we're stroking, do a save/restore.
111        GraphicsContextStateSaver stateSaver(*m_savedDrawingStateForMask.m_context, m_savedDrawingStateForMask.m_textPaintStyle->strokeWidth > 0);
112
113        updateGraphicsContext(*m_savedDrawingStateForMask.m_context, *m_savedDrawingStateForMask.m_textPaintStyle);
114        if (!m_paintSelectedTextSeparately || m_endPositionInTextRun <= m_startPositionInTextRun) {
115            // FIXME: Truncate right-to-left text correctly.
116            paintTextWithShadows(m_savedDrawingStateForMask.m_context, m_font, m_textRun, nullAtom, 0, 0, m_length, m_length, m_textOrigin, m_boxRect, m_savedDrawingStateForMask.m_textShadow, m_savedDrawingStateForMask.m_textPaintStyle->strokeWidth > 0, m_textBoxIsHorizontal);
117        } else
118            paintTextWithShadows(m_savedDrawingStateForMask.m_context, m_font, m_textRun, nullAtom, 0, m_endPositionInTextRun, m_startPositionInTextRun, m_length, m_textOrigin, m_boxRect, m_savedDrawingStateForMask.m_textShadow, m_savedDrawingStateForMask.m_textPaintStyle->strokeWidth > 0, m_textBoxIsHorizontal);
119
120        if (!m_emphasisMark.isEmpty()) {
121            updateGraphicsContext(*m_savedDrawingStateForMask.m_context, *m_savedDrawingStateForMask.m_textPaintStyle, UseEmphasisMarkColor);
122
123            DEPRECATED_DEFINE_STATIC_LOCAL(TextRun, objectReplacementCharacterTextRun, (&objectReplacementCharacter, 1));
124            TextRun& emphasisMarkTextRun = m_combinedText ? objectReplacementCharacterTextRun : m_textRun;
125            FloatPoint emphasisMarkTextOrigin = m_combinedText ? FloatPoint(boxOrigin.x() + m_boxRect.width() / 2, boxOrigin.y() + m_font.fontMetrics().ascent()) : m_textOrigin;
126            if (m_combinedText)
127                m_savedDrawingStateForMask.m_context->concatCTM(rotation(m_boxRect, Clockwise));
128
129            if (!m_paintSelectedTextSeparately || m_endPositionInTextRun <= m_startPositionInTextRun) {
130                // FIXME: Truncate right-to-left text correctly.
131                paintTextWithShadows(m_savedDrawingStateForMask.m_context, m_combinedText ? m_combinedText->originalFont() : m_font, emphasisMarkTextRun, m_emphasisMark, m_emphasisMarkOffset, 0, m_length, m_length, emphasisMarkTextOrigin, m_boxRect, m_savedDrawingStateForMask.m_textShadow, m_savedDrawingStateForMask.m_textPaintStyle->strokeWidth > 0, m_textBoxIsHorizontal);
132            } else
133                paintTextWithShadows(m_savedDrawingStateForMask.m_context, m_combinedText ? m_combinedText->originalFont() : m_font, emphasisMarkTextRun, m_emphasisMark, m_emphasisMarkOffset, m_endPositionInTextRun, m_startPositionInTextRun, m_length, emphasisMarkTextOrigin, m_boxRect, m_savedDrawingStateForMask.m_textShadow, m_savedDrawingStateForMask.m_textPaintStyle->strokeWidth > 0, m_textBoxIsHorizontal);
134
135            if (m_combinedText)
136                m_savedDrawingStateForMask.m_context->concatCTM(rotation(m_boxRect, Counterclockwise));
137        }
138    }
139
140    if ((m_paintSelectedTextOnly || m_paintSelectedTextSeparately) && m_startPositionInTextRun < m_endPositionInTextRun) {
141        // paint only the text that is selected
142        GraphicsContextStateSaver stateSaver(*m_savedDrawingStateForMask.m_context, m_savedDrawingStateForMask.m_selectionPaintStyle->strokeWidth > 0);
143
144        updateGraphicsContext(*m_savedDrawingStateForMask.m_context, *m_savedDrawingStateForMask.m_selectionPaintStyle);
145        paintTextWithShadows(m_savedDrawingStateForMask.m_context, m_font, m_textRun, nullAtom, 0, m_startPositionInTextRun, m_endPositionInTextRun, m_length, m_textOrigin, m_boxRect, m_savedDrawingStateForMask.m_selectionShadow, m_savedDrawingStateForMask.m_selectionPaintStyle->strokeWidth > 0, m_textBoxIsHorizontal);
146        if (!m_emphasisMark.isEmpty()) {
147            updateGraphicsContext(*m_savedDrawingStateForMask.m_context, *m_savedDrawingStateForMask.m_selectionPaintStyle, UseEmphasisMarkColor);
148
149            DEPRECATED_DEFINE_STATIC_LOCAL(TextRun, objectReplacementCharacterTextRun, (&objectReplacementCharacter, 1));
150            TextRun& emphasisMarkTextRun = m_combinedText ? objectReplacementCharacterTextRun : m_textRun;
151            FloatPoint emphasisMarkTextOrigin = m_combinedText ? FloatPoint(boxOrigin.x() + m_boxRect.width() / 2, boxOrigin.y() + m_font.fontMetrics().ascent()) : m_textOrigin;
152            if (m_combinedText)
153                m_savedDrawingStateForMask.m_context->concatCTM(rotation(m_boxRect, Clockwise));
154
155            paintTextWithShadows(m_savedDrawingStateForMask.m_context, m_combinedText ? m_combinedText->originalFont() : m_font, emphasisMarkTextRun, m_emphasisMark, m_emphasisMarkOffset, m_startPositionInTextRun, m_endPositionInTextRun, m_length, emphasisMarkTextOrigin, m_boxRect, m_savedDrawingStateForMask.m_selectionShadow, m_savedDrawingStateForMask.m_selectionPaintStyle->strokeWidth > 0, m_textBoxIsHorizontal);
156
157            if (m_combinedText)
158                m_savedDrawingStateForMask.m_context->concatCTM(rotation(m_boxRect, Counterclockwise));
159        }
160    }
161}
162
163void TextPainter::paintTextInContext(GraphicsContext& context, float amountToIncreaseStrokeWidthBy)
164{
165    SavedDrawingStateForMask savedDrawingStateForMask = m_savedDrawingStateForMask;
166
167    ASSERT(m_savedDrawingStateForMask.m_textPaintStyle);
168    ASSERT(m_savedDrawingStateForMask.m_selectionPaintStyle);
169    m_savedDrawingStateForMask.m_context = &context;
170    m_savedDrawingStateForMask.m_textPaintStyle->strokeWidth += amountToIncreaseStrokeWidthBy;
171    m_savedDrawingStateForMask.m_selectionPaintStyle->strokeWidth += amountToIncreaseStrokeWidthBy;
172    m_savedDrawingStateForMask.m_textShadow = nullptr;
173    m_savedDrawingStateForMask.m_selectionShadow = nullptr;
174    paintText();
175
176    m_savedDrawingStateForMask = savedDrawingStateForMask;
177}
178
179#if ENABLE(CSS3_TEXT_DECORATION_SKIP_INK)
180DashArray TextPainter::dashesForIntersectionsWithRect(const FloatRect& lineExtents)
181{
182    return m_font.dashesForIntersectionsWithRect(m_textRun, m_textOrigin, lineExtents);
183}
184#endif
185
186} // namespace WebCore
187