1 /*
2 * Copyright (C) 2007 Alp Toker <alp@atoker.com>
3 * Copyright (C) 2007 Apple Inc.
4 *
5 * This library is free software; you can redistribute it and/or
6 * modify it under the terms of the GNU Library General Public
7 * License as published by the Free Software Foundation; either
8 * version 2 of the License, or (at your option) any later version.
9 *
10 * This library is distributed in the hope that it will be useful,
11 * but WITHOUT ANY WARRANTY; without even the implied warranty of
12 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
13 * Library General Public License for more details.
14 *
15 * You should have received a copy of the GNU Library General Public License
16 * along with this library; see the file COPYING.LIB. If not, write to
17 * the Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor,
18 * Boston, MA 02110-1301, USA.
19 */
20
21 #include "config.h"
22 #include "PrintContext.h"
23
24 #include "GraphicsContext.h"
25 #include "Frame.h"
26 #include "FrameView.h"
27 #include "RenderLayer.h"
28 #include "RenderView.h"
29 #include <wtf/text/StringConcatenate.h>
30
31 namespace WebCore {
32
33 // By imaging to a width a little wider than the available pixels,
34 // thin pages will be scaled down a little, matching the way they
35 // print in IE and Camino. This lets them use fewer sheets than they
36 // would otherwise, which is presumably why other browsers do this.
37 // Wide pages will be scaled down more than this.
38 const float printingMinimumShrinkFactor = 1.25f;
39
40 // This number determines how small we are willing to reduce the page content
41 // in order to accommodate the widest line. If the page would have to be
42 // reduced smaller to make the widest line fit, we just clip instead (this
43 // behavior matches MacIE and Mozilla, at least)
44 const float printingMaximumShrinkFactor = 2;
45
PrintContext(Frame * frame)46 PrintContext::PrintContext(Frame* frame)
47 : m_frame(frame)
48 , m_isPrinting(false)
49 {
50 }
51
~PrintContext()52 PrintContext::~PrintContext()
53 {
54 if (m_isPrinting)
55 end();
56 }
57
computePageRects(const FloatRect & printRect,float headerHeight,float footerHeight,float userScaleFactor,float & outPageHeight,bool allowHorizontalTiling)58 void PrintContext::computePageRects(const FloatRect& printRect, float headerHeight, float footerHeight, float userScaleFactor, float& outPageHeight, bool allowHorizontalTiling)
59 {
60 m_pageRects.clear();
61 outPageHeight = 0;
62
63 if (!m_frame->document() || !m_frame->view() || !m_frame->document()->renderer())
64 return;
65
66 if (userScaleFactor <= 0) {
67 LOG_ERROR("userScaleFactor has bad value %.2f", userScaleFactor);
68 return;
69 }
70
71 RenderView* view = toRenderView(m_frame->document()->renderer());
72
73 bool isHorizontal = view->style()->isHorizontalWritingMode();
74
75 float pageWidth;
76 float pageHeight;
77 if (isHorizontal) {
78 float ratio = printRect.height() / printRect.width();
79 pageWidth = view->docWidth();
80 pageHeight = floorf(pageWidth * ratio);
81 } else {
82 float ratio = printRect.width() / printRect.height();
83 pageHeight = view->docHeight();
84 pageWidth = floorf(pageHeight * ratio);
85 }
86
87 outPageHeight = pageHeight; // this is the height of the page adjusted by margins
88 pageHeight -= headerHeight + footerHeight;
89
90 if (pageHeight <= 0) {
91 LOG_ERROR("pageHeight has bad value %.2f", pageHeight);
92 return;
93 }
94
95 computePageRectsWithPageSizeInternal(FloatSize(pageWidth / userScaleFactor, pageHeight / userScaleFactor), allowHorizontalTiling);
96 }
97
computePageRectsWithPageSize(const FloatSize & pageSizeInPixels,bool allowHorizontalTiling)98 void PrintContext::computePageRectsWithPageSize(const FloatSize& pageSizeInPixels, bool allowHorizontalTiling)
99 {
100 m_pageRects.clear();
101 computePageRectsWithPageSizeInternal(pageSizeInPixels, allowHorizontalTiling);
102 }
103
computePageRectsWithPageSizeInternal(const FloatSize & pageSizeInPixels,bool allowInlineDirectionTiling)104 void PrintContext::computePageRectsWithPageSizeInternal(const FloatSize& pageSizeInPixels, bool allowInlineDirectionTiling)
105 {
106 if (!m_frame->document() || !m_frame->view() || !m_frame->document()->renderer())
107 return;
108
109 RenderView* view = toRenderView(m_frame->document()->renderer());
110
111 IntRect docRect = view->documentRect();
112
113 int pageWidth = pageSizeInPixels.width();
114 int pageHeight = pageSizeInPixels.height();
115
116 bool isHorizontal = view->style()->isHorizontalWritingMode();
117
118 int docLogicalHeight = isHorizontal ? docRect.height() : docRect.width();
119 int pageLogicalHeight = isHorizontal ? pageHeight : pageWidth;
120 int pageLogicalWidth = isHorizontal ? pageWidth : pageHeight;
121
122 int inlineDirectionStart;
123 int inlineDirectionEnd;
124 int blockDirectionStart;
125 int blockDirectionEnd;
126 if (isHorizontal) {
127 if (view->style()->isFlippedBlocksWritingMode()) {
128 blockDirectionStart = docRect.maxY();
129 blockDirectionEnd = docRect.y();
130 } else {
131 blockDirectionStart = docRect.y();
132 blockDirectionEnd = docRect.maxY();
133 }
134 inlineDirectionStart = view->style()->isLeftToRightDirection() ? docRect.x() : docRect.maxX();
135 inlineDirectionEnd = view->style()->isLeftToRightDirection() ? docRect.maxX() : docRect.x();
136 } else {
137 if (view->style()->isFlippedBlocksWritingMode()) {
138 blockDirectionStart = docRect.maxX();
139 blockDirectionEnd = docRect.x();
140 } else {
141 blockDirectionStart = docRect.x();
142 blockDirectionEnd = docRect.maxX();
143 }
144 inlineDirectionStart = view->style()->isLeftToRightDirection() ? docRect.y() : docRect.maxY();
145 inlineDirectionEnd = view->style()->isLeftToRightDirection() ? docRect.maxY() : docRect.y();
146 }
147
148 unsigned pageCount = ceilf((float)docLogicalHeight / pageLogicalHeight);
149 for (unsigned i = 0; i < pageCount; ++i) {
150 int pageLogicalTop = blockDirectionEnd > blockDirectionStart ?
151 blockDirectionStart + i * pageLogicalHeight :
152 blockDirectionStart - (i + 1) * pageLogicalHeight;
153 if (allowInlineDirectionTiling) {
154 for (int currentInlinePosition = inlineDirectionStart;
155 inlineDirectionEnd > inlineDirectionStart ? currentInlinePosition < inlineDirectionEnd : currentInlinePosition > inlineDirectionEnd;
156 currentInlinePosition += (inlineDirectionEnd > inlineDirectionStart ? pageLogicalWidth : -pageLogicalWidth)) {
157 int pageLogicalLeft = inlineDirectionEnd > inlineDirectionStart ? currentInlinePosition : currentInlinePosition - pageLogicalWidth;
158 IntRect pageRect(pageLogicalLeft, pageLogicalTop, pageLogicalWidth, pageLogicalHeight);
159 if (!isHorizontal)
160 pageRect = pageRect.transposedRect();
161 m_pageRects.append(pageRect);
162 }
163 } else {
164 int pageLogicalLeft = inlineDirectionEnd > inlineDirectionStart ? inlineDirectionStart : inlineDirectionStart - pageLogicalWidth;
165 IntRect pageRect(pageLogicalLeft, pageLogicalTop, pageLogicalWidth, pageLogicalHeight);
166 if (!isHorizontal)
167 pageRect = pageRect.transposedRect();
168 m_pageRects.append(pageRect);
169 }
170 }
171 }
172
begin(float width,float height)173 void PrintContext::begin(float width, float height)
174 {
175 // This function can be called multiple times to adjust printing parameters without going back to screen mode.
176 m_isPrinting = true;
177
178 float minLayoutWidth = width * printingMinimumShrinkFactor;
179 float minLayoutHeight = height * printingMinimumShrinkFactor;
180
181 // This changes layout, so callers need to make sure that they don't paint to screen while in printing mode.
182 m_frame->setPrinting(true, FloatSize(minLayoutWidth, minLayoutHeight), printingMaximumShrinkFactor / printingMinimumShrinkFactor, Frame::AdjustViewSize);
183 }
184
computeAutomaticScaleFactor(const FloatSize & availablePaperSize)185 float PrintContext::computeAutomaticScaleFactor(const FloatSize& availablePaperSize)
186 {
187 if (!m_frame->view())
188 return 1;
189
190 bool useViewWidth = true;
191 if (m_frame->document() && m_frame->document()->renderView())
192 useViewWidth = m_frame->document()->renderView()->style()->isHorizontalWritingMode();
193
194 float viewLogicalWidth = useViewWidth ? m_frame->view()->contentsWidth() : m_frame->view()->contentsHeight();
195 if (viewLogicalWidth < 1)
196 return 1;
197
198 float maxShrinkToFitScaleFactor = 1 / printingMaximumShrinkFactor;
199 float shrinkToFitScaleFactor = (useViewWidth ? availablePaperSize.width() : availablePaperSize.height()) / viewLogicalWidth;
200 return max(maxShrinkToFitScaleFactor, shrinkToFitScaleFactor);
201 }
202
spoolPage(GraphicsContext & ctx,int pageNumber,float width)203 void PrintContext::spoolPage(GraphicsContext& ctx, int pageNumber, float width)
204 {
205 // FIXME: Not correct for vertical text.
206 IntRect pageRect = m_pageRects[pageNumber];
207 float scale = width / pageRect.width();
208
209 ctx.save();
210 ctx.scale(FloatSize(scale, scale));
211 ctx.translate(-pageRect.x(), -pageRect.y());
212 ctx.clip(pageRect);
213 m_frame->view()->paintContents(&ctx, pageRect);
214 ctx.restore();
215 }
216
spoolRect(GraphicsContext & ctx,const IntRect & rect)217 void PrintContext::spoolRect(GraphicsContext& ctx, const IntRect& rect)
218 {
219 // FIXME: Not correct for vertical text.
220 ctx.save();
221 ctx.translate(-rect.x(), -rect.y());
222 ctx.clip(rect);
223 m_frame->view()->paintContents(&ctx, rect);
224 ctx.restore();
225 }
226
end()227 void PrintContext::end()
228 {
229 ASSERT(m_isPrinting);
230 m_isPrinting = false;
231 m_frame->setPrinting(false, FloatSize(), 0, Frame::AdjustViewSize);
232 }
233
enclosingBoxModelObject(RenderObject * object)234 static RenderBoxModelObject* enclosingBoxModelObject(RenderObject* object)
235 {
236
237 while (object && !object->isBoxModelObject())
238 object = object->parent();
239 if (!object)
240 return 0;
241 return toRenderBoxModelObject(object);
242 }
243
pageNumberForElement(Element * element,const FloatSize & pageSizeInPixels)244 int PrintContext::pageNumberForElement(Element* element, const FloatSize& pageSizeInPixels)
245 {
246 // Make sure the element is not freed during the layout.
247 RefPtr<Element> elementRef(element);
248 element->document()->updateLayout();
249
250 RenderBoxModelObject* box = enclosingBoxModelObject(element->renderer());
251 if (!box)
252 return -1;
253
254 Frame* frame = element->document()->frame();
255 FloatRect pageRect(FloatPoint(0, 0), pageSizeInPixels);
256 PrintContext printContext(frame);
257 printContext.begin(pageRect.width(), pageRect.height());
258 FloatSize scaledPageSize = pageSizeInPixels;
259 scaledPageSize.scale(frame->view()->contentsSize().width() / pageRect.width());
260 printContext.computePageRectsWithPageSize(scaledPageSize, false);
261
262 int top = box->offsetTop();
263 int left = box->offsetLeft();
264 size_t pageNumber = 0;
265 for (; pageNumber < printContext.pageCount(); pageNumber++) {
266 const IntRect& page = printContext.pageRect(pageNumber);
267 if (page.x() <= left && left < page.maxX() && page.y() <= top && top < page.maxY())
268 return pageNumber;
269 }
270 return -1;
271 }
272
pageProperty(Frame * frame,const char * propertyName,int pageNumber)273 String PrintContext::pageProperty(Frame* frame, const char* propertyName, int pageNumber)
274 {
275 Document* document = frame->document();
276 PrintContext printContext(frame);
277 printContext.begin(800); // Any width is OK here.
278 document->updateLayout();
279 RefPtr<RenderStyle> style = document->styleForPage(pageNumber);
280
281 // Implement formatters for properties we care about.
282 if (!strcmp(propertyName, "margin-left")) {
283 if (style->marginLeft().isAuto())
284 return String("auto");
285 return String::number(style->marginLeft().value());
286 }
287 if (!strcmp(propertyName, "line-height"))
288 return String::number(style->lineHeight().value());
289 if (!strcmp(propertyName, "font-size"))
290 return String::number(style->fontDescription().computedPixelSize());
291 if (!strcmp(propertyName, "font-family"))
292 return style->fontDescription().family().family().string();
293 if (!strcmp(propertyName, "size"))
294 return makeString(String::number(style->pageSize().width().value()), ' ', String::number(style->pageSize().height().value()));
295
296 return makeString("pageProperty() unimplemented for: ", propertyName);
297 }
298
isPageBoxVisible(Frame * frame,int pageNumber)299 bool PrintContext::isPageBoxVisible(Frame* frame, int pageNumber)
300 {
301 return frame->document()->isPageBoxVisible(pageNumber);
302 }
303
pageSizeAndMarginsInPixels(Frame * frame,int pageNumber,int width,int height,int marginTop,int marginRight,int marginBottom,int marginLeft)304 String PrintContext::pageSizeAndMarginsInPixels(Frame* frame, int pageNumber, int width, int height, int marginTop, int marginRight, int marginBottom, int marginLeft)
305 {
306 IntSize pageSize(width, height);
307 frame->document()->pageSizeAndMarginsInPixels(pageNumber, pageSize, marginTop, marginRight, marginBottom, marginLeft);
308
309 // We don't have a makeString() function that takes up to 12 arguments, if this is a hot function, we can provide one.
310 return makeString('(', String::number(pageSize.width()), ", ", String::number(pageSize.height()), ") ") +
311 makeString(String::number(marginTop), ' ', String::number(marginRight), ' ', String::number(marginBottom), ' ', String::number(marginLeft));
312 }
313
numberOfPages(Frame * frame,const FloatSize & pageSizeInPixels)314 int PrintContext::numberOfPages(Frame* frame, const FloatSize& pageSizeInPixels)
315 {
316 frame->document()->updateLayout();
317
318 FloatRect pageRect(FloatPoint(0, 0), pageSizeInPixels);
319 PrintContext printContext(frame);
320 printContext.begin(pageRect.width(), pageRect.height());
321 // Account for shrink-to-fit.
322 FloatSize scaledPageSize = pageSizeInPixels;
323 scaledPageSize.scale(frame->view()->contentsSize().width() / pageRect.width());
324 printContext.computePageRectsWithPageSize(scaledPageSize, false);
325 return printContext.pageCount();
326 }
327
spoolAllPagesWithBoundaries(Frame * frame,GraphicsContext & graphicsContext,const FloatSize & pageSizeInPixels)328 void PrintContext::spoolAllPagesWithBoundaries(Frame* frame, GraphicsContext& graphicsContext, const FloatSize& pageSizeInPixels)
329 {
330 if (!frame->document() || !frame->view() || !frame->document()->renderer())
331 return;
332
333 frame->document()->updateLayout();
334
335 PrintContext printContext(frame);
336 printContext.begin(pageSizeInPixels.width(), pageSizeInPixels.height());
337
338 float pageHeight;
339 printContext.computePageRects(FloatRect(FloatPoint(0, 0), pageSizeInPixels), 0, 0, 1, pageHeight);
340
341 const float pageWidth = pageSizeInPixels.width();
342 const Vector<IntRect>& pageRects = printContext.pageRects();
343 int totalHeight = pageRects.size() * (pageSizeInPixels.height() + 1) - 1;
344
345 // Fill the whole background by white.
346 graphicsContext.setFillColor(Color(255, 255, 255), ColorSpaceDeviceRGB);
347 graphicsContext.fillRect(FloatRect(0, 0, pageWidth, totalHeight));
348
349 graphicsContext.save();
350 graphicsContext.translate(0, totalHeight);
351 graphicsContext.scale(FloatSize(1, -1));
352
353 int currentHeight = 0;
354 for (size_t pageIndex = 0; pageIndex < pageRects.size(); pageIndex++) {
355 // Draw a line for a page boundary if this isn't the first page.
356 if (pageIndex > 0) {
357 graphicsContext.save();
358 graphicsContext.setStrokeColor(Color(0, 0, 255), ColorSpaceDeviceRGB);
359 graphicsContext.setFillColor(Color(0, 0, 255), ColorSpaceDeviceRGB);
360 graphicsContext.drawLine(IntPoint(0, currentHeight),
361 IntPoint(pageWidth, currentHeight));
362 graphicsContext.restore();
363 }
364
365 graphicsContext.save();
366 graphicsContext.translate(0, currentHeight);
367 printContext.spoolPage(graphicsContext, pageIndex, pageWidth);
368 graphicsContext.restore();
369
370 currentHeight += pageSizeInPixels.height() + 1;
371 }
372
373 graphicsContext.restore();
374 }
375
376 }
377