1 /*
2 * Copyright (C) 2009 Google Inc. All rights reserved.
3 *
4 * Redistribution and use in source and binary forms, with or without
5 * modification, are permitted provided that the following conditions are
6 * met:
7 *
8 * * Redistributions of source code must retain the above copyright
9 * notice, this list of conditions and the following disclaimer.
10 * * Redistributions in binary form must reproduce the above
11 * copyright notice, this list of conditions and the following disclaimer
12 * in the documentation and/or other materials provided with the
13 * distribution.
14 * * Neither the name of Google Inc. nor the names of its
15 * contributors may be used to endorse or promote products derived from
16 * this software without specific prior written permission.
17 *
18 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
19 * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
20 * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
21 * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
22 * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
23 * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
24 * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
25 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
26 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
27 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
28 * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
29 */
30
31 #include "config.h"
32
33 #include "core/rendering/RenderRubyRun.h"
34
35 #include "core/rendering/RenderRubyBase.h"
36 #include "core/rendering/RenderRubyText.h"
37 #include "core/rendering/RenderText.h"
38
39 namespace blink {
40
RenderRubyRun()41 RenderRubyRun::RenderRubyRun()
42 : RenderBlockFlow(0)
43 {
44 setReplaced(true);
45 setInline(true);
46 }
47
~RenderRubyRun()48 RenderRubyRun::~RenderRubyRun()
49 {
50 }
51
hasRubyText() const52 bool RenderRubyRun::hasRubyText() const
53 {
54 // The only place where a ruby text can be is in the first position
55 // Note: As anonymous blocks, ruby runs do not have ':before' or ':after' content themselves.
56 return firstChild() && firstChild()->isRubyText();
57 }
58
hasRubyBase() const59 bool RenderRubyRun::hasRubyBase() const
60 {
61 // The only place where a ruby base can be is in the last position
62 // Note: As anonymous blocks, ruby runs do not have ':before' or ':after' content themselves.
63 return lastChild() && lastChild()->isRubyBase();
64 }
65
rubyText() const66 RenderRubyText* RenderRubyRun::rubyText() const
67 {
68 RenderObject* child = firstChild();
69 // If in future it becomes necessary to support floating or positioned ruby text,
70 // layout will have to be changed to handle them properly.
71 ASSERT(!child || !child->isRubyText() || !child->isFloatingOrOutOfFlowPositioned());
72 return child && child->isRubyText() ? static_cast<RenderRubyText*>(child) : 0;
73 }
74
rubyBase() const75 RenderRubyBase* RenderRubyRun::rubyBase() const
76 {
77 RenderObject* child = lastChild();
78 return child && child->isRubyBase() ? static_cast<RenderRubyBase*>(child) : 0;
79 }
80
rubyBaseSafe()81 RenderRubyBase* RenderRubyRun::rubyBaseSafe()
82 {
83 RenderRubyBase* base = rubyBase();
84 if (!base) {
85 base = createRubyBase();
86 RenderBlockFlow::addChild(base);
87 }
88 return base;
89 }
90
isChildAllowed(RenderObject * child,RenderStyle *) const91 bool RenderRubyRun::isChildAllowed(RenderObject* child, RenderStyle*) const
92 {
93 return child->isRubyText() || child->isInline();
94 }
95
addChild(RenderObject * child,RenderObject * beforeChild)96 void RenderRubyRun::addChild(RenderObject* child, RenderObject* beforeChild)
97 {
98 ASSERT(child);
99
100 if (child->isRubyText()) {
101 if (!beforeChild) {
102 // RenderRuby has already ascertained that we can add the child here.
103 ASSERT(!hasRubyText());
104 // prepend ruby texts as first child
105 RenderBlockFlow::addChild(child, firstChild());
106 } else if (beforeChild->isRubyText()) {
107 // New text is inserted just before another.
108 // In this case the new text takes the place of the old one, and
109 // the old text goes into a new run that is inserted as next sibling.
110 ASSERT(beforeChild->parent() == this);
111 RenderObject* ruby = parent();
112 ASSERT(ruby->isRuby());
113 RenderBlock* newRun = staticCreateRubyRun(ruby);
114 ruby->addChild(newRun, nextSibling());
115 // Add the new ruby text and move the old one to the new run
116 // Note: Doing it in this order and not using RenderRubyRun's methods,
117 // in order to avoid automatic removal of the ruby run in case there is no
118 // other child besides the old ruby text.
119 RenderBlockFlow::addChild(child, beforeChild);
120 RenderBlockFlow::removeChild(beforeChild);
121 newRun->addChild(beforeChild);
122 } else if (hasRubyBase()) {
123 // Insertion before a ruby base object.
124 // In this case we need insert a new run before the current one and split the base.
125 RenderObject* ruby = parent();
126 RenderRubyRun* newRun = staticCreateRubyRun(ruby);
127 ruby->addChild(newRun, this);
128 newRun->addChild(child);
129 rubyBaseSafe()->moveChildren(newRun->rubyBaseSafe(), beforeChild);
130 }
131 } else {
132 // child is not a text -> insert it into the base
133 // (append it instead if beforeChild is the ruby text)
134 if (beforeChild && beforeChild->isRubyText())
135 beforeChild = 0;
136 rubyBaseSafe()->addChild(child, beforeChild);
137 }
138 }
139
removeChild(RenderObject * child)140 void RenderRubyRun::removeChild(RenderObject* child)
141 {
142 // If the child is a ruby text, then merge the ruby base with the base of
143 // the right sibling run, if possible.
144 if (!beingDestroyed() && !documentBeingDestroyed() && child->isRubyText()) {
145 RenderRubyBase* base = rubyBase();
146 RenderObject* rightNeighbour = nextSibling();
147 if (base && rightNeighbour && rightNeighbour->isRubyRun()) {
148 // Ruby run without a base can happen only at the first run.
149 RenderRubyRun* rightRun = toRenderRubyRun(rightNeighbour);
150 if (rightRun->hasRubyBase()) {
151 RenderRubyBase* rightBase = rightRun->rubyBaseSafe();
152 // Collect all children in a single base, then swap the bases.
153 rightBase->moveChildren(base);
154 moveChildTo(rightRun, base);
155 rightRun->moveChildTo(this, rightBase);
156 // The now empty ruby base will be removed below.
157 ASSERT(!rubyBase()->firstChild());
158 }
159 }
160 }
161
162 RenderBlockFlow::removeChild(child);
163
164 if (!beingDestroyed() && !documentBeingDestroyed()) {
165 // Check if our base (if any) is now empty. If so, destroy it.
166 RenderBlock* base = rubyBase();
167 if (base && !base->firstChild()) {
168 RenderBlockFlow::removeChild(base);
169 base->deleteLineBoxTree();
170 base->destroy();
171 }
172
173 // If any of the above leaves the run empty, destroy it as well.
174 if (!hasRubyText() && !hasRubyBase()) {
175 deleteLineBoxTree();
176 destroy();
177 }
178 }
179 }
180
createRubyBase() const181 RenderRubyBase* RenderRubyRun::createRubyBase() const
182 {
183 RenderRubyBase* renderer = RenderRubyBase::createAnonymous(&document());
184 RefPtr<RenderStyle> newStyle = RenderStyle::createAnonymousStyleWithDisplay(style(), BLOCK);
185 newStyle->setTextAlign(CENTER); // FIXME: use WEBKIT_CENTER?
186 renderer->setStyle(newStyle.release());
187 return renderer;
188 }
189
staticCreateRubyRun(const RenderObject * parentRuby)190 RenderRubyRun* RenderRubyRun::staticCreateRubyRun(const RenderObject* parentRuby)
191 {
192 ASSERT(parentRuby && parentRuby->isRuby());
193 RenderRubyRun* rr = new RenderRubyRun();
194 rr->setDocumentForAnonymous(&parentRuby->document());
195 RefPtr<RenderStyle> newStyle = RenderStyle::createAnonymousStyleWithDisplay(parentRuby->style(), INLINE_BLOCK);
196 rr->setStyle(newStyle.release());
197 return rr;
198 }
199
layoutSpecialExcludedChild(bool relayoutChildren,SubtreeLayoutScope & layoutScope)200 RenderObject* RenderRubyRun::layoutSpecialExcludedChild(bool relayoutChildren, SubtreeLayoutScope& layoutScope)
201 {
202 // Don't bother positioning the RenderRubyRun yet.
203 RenderRubyText* rt = rubyText();
204 if (!rt)
205 return 0;
206 if (relayoutChildren)
207 layoutScope.setChildNeedsLayout(rt);
208 rt->layoutIfNeeded();
209 return rt;
210 }
211
layout()212 void RenderRubyRun::layout()
213 {
214 RenderBlockFlow::layout();
215
216 RenderRubyText* rt = rubyText();
217 if (!rt)
218 return;
219
220 rt->setLogicalLeft(0);
221
222 // Place the RenderRubyText such that its bottom is flush with the lineTop of the first line of the RenderRubyBase.
223 LayoutUnit lastLineRubyTextBottom = rt->logicalHeight();
224 LayoutUnit firstLineRubyTextTop = 0;
225 RootInlineBox* rootBox = rt->lastRootBox();
226 if (rootBox) {
227 // In order to align, we have to ignore negative leading.
228 firstLineRubyTextTop = rt->firstRootBox()->logicalTopLayoutOverflow();
229 lastLineRubyTextBottom = rootBox->logicalBottomLayoutOverflow();
230 }
231
232 if (style()->isFlippedLinesWritingMode() == (style()->rubyPosition() == RubyPositionAfter)) {
233 LayoutUnit firstLineTop = 0;
234 if (RenderRubyBase* rb = rubyBase()) {
235 RootInlineBox* rootBox = rb->firstRootBox();
236 if (rootBox)
237 firstLineTop = rootBox->logicalTopLayoutOverflow();
238 firstLineTop += rb->logicalTop();
239 }
240
241 rt->setLogicalTop(-lastLineRubyTextBottom + firstLineTop);
242 } else {
243 LayoutUnit lastLineBottom = logicalHeight();
244 if (RenderRubyBase* rb = rubyBase()) {
245 RootInlineBox* rootBox = rb->lastRootBox();
246 if (rootBox)
247 lastLineBottom = rootBox->logicalBottomLayoutOverflow();
248 lastLineBottom += rb->logicalTop();
249 }
250
251 rt->setLogicalTop(-firstLineRubyTextTop + lastLineBottom);
252 }
253
254 // Update our overflow to account for the new RenderRubyText position.
255 computeOverflow(clientLogicalBottom());
256 }
257
getOverhang(bool firstLine,RenderObject * startRenderer,RenderObject * endRenderer,int & startOverhang,int & endOverhang) const258 void RenderRubyRun::getOverhang(bool firstLine, RenderObject* startRenderer, RenderObject* endRenderer, int& startOverhang, int& endOverhang) const
259 {
260 ASSERT(!needsLayout());
261
262 startOverhang = 0;
263 endOverhang = 0;
264
265 RenderRubyBase* rubyBase = this->rubyBase();
266 RenderRubyText* rubyText = this->rubyText();
267
268 if (!rubyBase || !rubyText)
269 return;
270
271 if (!rubyBase->firstRootBox())
272 return;
273
274 int logicalWidth = this->logicalWidth();
275 int logicalLeftOverhang = std::numeric_limits<int>::max();
276 int logicalRightOverhang = std::numeric_limits<int>::max();
277 for (RootInlineBox* rootInlineBox = rubyBase->firstRootBox(); rootInlineBox; rootInlineBox = rootInlineBox->nextRootBox()) {
278 logicalLeftOverhang = std::min<int>(logicalLeftOverhang, rootInlineBox->logicalLeft());
279 logicalRightOverhang = std::min<int>(logicalRightOverhang, logicalWidth - rootInlineBox->logicalRight());
280 }
281
282 startOverhang = style()->isLeftToRightDirection() ? logicalLeftOverhang : logicalRightOverhang;
283 endOverhang = style()->isLeftToRightDirection() ? logicalRightOverhang : logicalLeftOverhang;
284
285 if (!startRenderer || !startRenderer->isText() || startRenderer->style(firstLine)->fontSize() > rubyBase->style(firstLine)->fontSize())
286 startOverhang = 0;
287
288 if (!endRenderer || !endRenderer->isText() || endRenderer->style(firstLine)->fontSize() > rubyBase->style(firstLine)->fontSize())
289 endOverhang = 0;
290
291 // We overhang a ruby only if the neighboring render object is a text.
292 // We can overhang the ruby by no more than half the width of the neighboring text
293 // and no more than half the font size.
294 int halfWidthOfFontSize = rubyText->style(firstLine)->fontSize() / 2;
295 if (startOverhang)
296 startOverhang = std::min<int>(startOverhang, std::min<int>(toRenderText(startRenderer)->minLogicalWidth(), halfWidthOfFontSize));
297 if (endOverhang)
298 endOverhang = std::min<int>(endOverhang, std::min<int>(toRenderText(endRenderer)->minLogicalWidth(), halfWidthOfFontSize));
299 }
300
301 } // namespace blink
302