1 /*
2 * Copyright (C) 2006 Oliver Hunt <ojh16@student.canterbury.ac.nz>
3 * Copyright (C) 2006 Apple Computer Inc.
4 * Copyright (C) 2007 Nikolas Zimmermann <zimmermann@kde.org>
5 * Copyright (C) 2008 Rob Buis <buis@kde.org>
6 * Copyright (C) Research In Motion Limited 2010. All rights reserved.
7 *
8 * This library is free software; you can redistribute it and/or
9 * modify it under the terms of the GNU Library General Public
10 * License as published by the Free Software Foundation; either
11 * version 2 of the License, or (at your option) any later version.
12 *
13 * This library is distributed in the hope that it will be useful,
14 * but WITHOUT ANY WARRANTY; without even the implied warranty of
15 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
16 * Library General Public License for more details.
17 *
18 * You should have received a copy of the GNU Library General Public License
19 * along with this library; see the file COPYING.LIB. If not, write to
20 * the Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor,
21 * Boston, MA 02110-1301, USA.
22 */
23
24 #include "config.h"
25
26 #include "core/rendering/svg/RenderSVGInlineText.h"
27
28 #include "core/css/CSSFontSelector.h"
29 #include "core/css/FontSize.h"
30 #include "core/dom/StyleEngine.h"
31 #include "core/editing/VisiblePosition.h"
32 #include "core/rendering/svg/RenderSVGText.h"
33 #include "core/rendering/svg/SVGInlineTextBox.h"
34 #include "core/rendering/svg/SVGRenderingContext.h"
35
36 namespace blink {
37
applySVGWhitespaceRules(PassRefPtr<StringImpl> string,bool preserveWhiteSpace)38 static PassRefPtr<StringImpl> applySVGWhitespaceRules(PassRefPtr<StringImpl> string, bool preserveWhiteSpace)
39 {
40 if (preserveWhiteSpace) {
41 // Spec: When xml:space="preserve", the SVG user agent will do the following using a
42 // copy of the original character data content. It will convert all newline and tab
43 // characters into space characters. Then, it will draw all space characters, including
44 // leading, trailing and multiple contiguous space characters.
45 RefPtr<StringImpl> newString = string->replace('\t', ' ');
46 newString = newString->replace('\n', ' ');
47 newString = newString->replace('\r', ' ');
48 return newString.release();
49 }
50
51 // Spec: When xml:space="default", the SVG user agent will do the following using a
52 // copy of the original character data content. First, it will remove all newline
53 // characters. Then it will convert all tab characters into space characters.
54 // Then, it will strip off all leading and trailing space characters.
55 // Then, all contiguous space characters will be consolidated.
56 RefPtr<StringImpl> newString = string->replace('\n', StringImpl::empty());
57 newString = newString->replace('\r', StringImpl::empty());
58 newString = newString->replace('\t', ' ');
59 return newString.release();
60 }
61
RenderSVGInlineText(Node * n,PassRefPtr<StringImpl> string)62 RenderSVGInlineText::RenderSVGInlineText(Node* n, PassRefPtr<StringImpl> string)
63 : RenderText(n, applySVGWhitespaceRules(string, false))
64 , m_scalingFactor(1)
65 , m_layoutAttributes(this)
66 {
67 }
68
setTextInternal(PassRefPtr<StringImpl> text)69 void RenderSVGInlineText::setTextInternal(PassRefPtr<StringImpl> text)
70 {
71 RenderText::setTextInternal(text);
72 if (RenderSVGText* textRenderer = RenderSVGText::locateRenderSVGTextAncestor(this))
73 textRenderer->subtreeTextDidChange(this);
74 }
75
styleDidChange(StyleDifference diff,const RenderStyle * oldStyle)76 void RenderSVGInlineText::styleDidChange(StyleDifference diff, const RenderStyle* oldStyle)
77 {
78 RenderText::styleDidChange(diff, oldStyle);
79 updateScaledFont();
80
81 bool newPreserves = style() ? style()->whiteSpace() == PRE : false;
82 bool oldPreserves = oldStyle ? oldStyle->whiteSpace() == PRE : false;
83 if (oldPreserves && !newPreserves) {
84 setText(applySVGWhitespaceRules(originalText(), false), true);
85 return;
86 }
87
88 if (!oldPreserves && newPreserves) {
89 setText(applySVGWhitespaceRules(originalText(), true), true);
90 return;
91 }
92
93 if (!diff.needsFullLayout())
94 return;
95
96 // The text metrics may be influenced by style changes.
97 if (RenderSVGText* textRenderer = RenderSVGText::locateRenderSVGTextAncestor(this))
98 textRenderer->setNeedsLayoutAndFullPaintInvalidation();
99 }
100
createTextBox()101 InlineTextBox* RenderSVGInlineText::createTextBox()
102 {
103 InlineTextBox* box = new SVGInlineTextBox(*this);
104 box->setHasVirtualLogicalHeight();
105 return box;
106 }
107
localCaretRect(InlineBox * box,int caretOffset,LayoutUnit *)108 LayoutRect RenderSVGInlineText::localCaretRect(InlineBox* box, int caretOffset, LayoutUnit*)
109 {
110 if (!box || !box->isInlineTextBox())
111 return LayoutRect();
112
113 InlineTextBox* textBox = toInlineTextBox(box);
114 if (static_cast<unsigned>(caretOffset) < textBox->start() || static_cast<unsigned>(caretOffset) > textBox->start() + textBox->len())
115 return LayoutRect();
116
117 // Use the edge of the selection rect to determine the caret rect.
118 if (static_cast<unsigned>(caretOffset) < textBox->start() + textBox->len()) {
119 LayoutRect rect = textBox->localSelectionRect(caretOffset, caretOffset + 1);
120 LayoutUnit x = box->isLeftToRightDirection() ? rect.x() : rect.maxX();
121 return LayoutRect(x, rect.y(), caretWidth, rect.height());
122 }
123
124 LayoutRect rect = textBox->localSelectionRect(caretOffset - 1, caretOffset);
125 LayoutUnit x = box->isLeftToRightDirection() ? rect.maxX() : rect.x();
126 return LayoutRect(x, rect.y(), caretWidth, rect.height());
127 }
128
floatLinesBoundingBox() const129 FloatRect RenderSVGInlineText::floatLinesBoundingBox() const
130 {
131 FloatRect boundingBox;
132 for (InlineTextBox* box = firstTextBox(); box; box = box->nextTextBox())
133 boundingBox.unite(box->calculateBoundaries());
134 return boundingBox;
135 }
136
linesBoundingBox() const137 IntRect RenderSVGInlineText::linesBoundingBox() const
138 {
139 return enclosingIntRect(floatLinesBoundingBox());
140 }
141
characterStartsNewTextChunk(int position) const142 bool RenderSVGInlineText::characterStartsNewTextChunk(int position) const
143 {
144 ASSERT(position >= 0);
145 ASSERT(position < static_cast<int>(textLength()));
146
147 // Each <textPath> element starts a new text chunk, regardless of any x/y values.
148 if (!position && parent()->isSVGTextPath() && !previousSibling())
149 return true;
150
151 const SVGCharacterDataMap::const_iterator it = m_layoutAttributes.characterDataMap().find(static_cast<unsigned>(position + 1));
152 if (it == m_layoutAttributes.characterDataMap().end())
153 return false;
154
155 return it->value.x != SVGTextLayoutAttributes::emptyValue() || it->value.y != SVGTextLayoutAttributes::emptyValue();
156 }
157
positionForPoint(const LayoutPoint & point)158 PositionWithAffinity RenderSVGInlineText::positionForPoint(const LayoutPoint& point)
159 {
160 if (!firstTextBox() || !textLength())
161 return createPositionWithAffinity(0, DOWNSTREAM);
162
163 float baseline = m_scaledFont.fontMetrics().floatAscent();
164
165 RenderBlock* containingBlock = this->containingBlock();
166 ASSERT(containingBlock);
167
168 // Map local point to absolute point, as the character origins stored in the text fragments use absolute coordinates.
169 FloatPoint absolutePoint(point);
170 absolutePoint.moveBy(containingBlock->location());
171
172 float closestDistance = std::numeric_limits<float>::max();
173 float closestDistancePosition = 0;
174 const SVGTextFragment* closestDistanceFragment = 0;
175 SVGInlineTextBox* closestDistanceBox = 0;
176
177 AffineTransform fragmentTransform;
178 for (InlineTextBox* box = firstTextBox(); box; box = box->nextTextBox()) {
179 if (!box->isSVGInlineTextBox())
180 continue;
181
182 SVGInlineTextBox* textBox = toSVGInlineTextBox(box);
183 Vector<SVGTextFragment>& fragments = textBox->textFragments();
184
185 unsigned textFragmentsSize = fragments.size();
186 for (unsigned i = 0; i < textFragmentsSize; ++i) {
187 const SVGTextFragment& fragment = fragments.at(i);
188 FloatRect fragmentRect(fragment.x, fragment.y - baseline, fragment.width, fragment.height);
189 fragment.buildFragmentTransform(fragmentTransform);
190 fragmentRect = fragmentTransform.mapRect(fragmentRect);
191
192 float distance = powf(fragmentRect.x() - absolutePoint.x(), 2) +
193 powf(fragmentRect.y() + fragmentRect.height() / 2 - absolutePoint.y(), 2);
194
195 if (distance < closestDistance) {
196 closestDistance = distance;
197 closestDistanceBox = textBox;
198 closestDistanceFragment = &fragment;
199 closestDistancePosition = fragmentRect.x();
200 }
201 }
202 }
203
204 if (!closestDistanceFragment)
205 return createPositionWithAffinity(0, DOWNSTREAM);
206
207 int offset = closestDistanceBox->offsetForPositionInFragment(*closestDistanceFragment, absolutePoint.x() - closestDistancePosition, true);
208 return createPositionWithAffinity(offset + closestDistanceBox->start(), offset > 0 ? VP_UPSTREAM_IF_POSSIBLE : DOWNSTREAM);
209 }
210
updateScaledFont()211 void RenderSVGInlineText::updateScaledFont()
212 {
213 computeNewScaledFontForStyle(this, style(), m_scalingFactor, m_scaledFont);
214 }
215
computeNewScaledFontForStyle(RenderObject * renderer,const RenderStyle * style,float & scalingFactor,Font & scaledFont)216 void RenderSVGInlineText::computeNewScaledFontForStyle(RenderObject* renderer, const RenderStyle* style, float& scalingFactor, Font& scaledFont)
217 {
218 ASSERT(style);
219 ASSERT(renderer);
220
221 // Alter font-size to the right on-screen value to avoid scaling the glyphs themselves, except when GeometricPrecision is specified.
222 scalingFactor = SVGRenderingContext::calculateScreenFontSizeScalingFactor(renderer);
223 if (style->effectiveZoom() == 1 && (scalingFactor == 1 || !scalingFactor)) {
224 scalingFactor = 1;
225 scaledFont = style->font();
226 return;
227 }
228
229 if (style->fontDescription().textRendering() == GeometricPrecision)
230 scalingFactor = 1;
231
232 FontDescription fontDescription(style->fontDescription());
233
234 Document& document = renderer->document();
235 // FIXME: We need to better handle the case when we compute very small fonts below (below 1pt).
236 fontDescription.setComputedSize(FontSize::getComputedSizeFromSpecifiedSize(&document, scalingFactor, fontDescription.isAbsoluteSize(), fontDescription.specifiedSize(), DoNotUseSmartMinimumForFontSize));
237
238 scaledFont = Font(fontDescription);
239 scaledFont.update(document.styleEngine()->fontSelector());
240 }
241
242 }
243