third_party/WebKit/Source/core/layout/LayoutTextTrackContainer.cpp

   1 /*
   2  * Copyright (C) 2008, 2009, 2010, 2011 Apple Inc. All rights reserved.
   3  * Copyright (C) 2012 Google Inc.
   4  * All rights reserved.
   5  *
   6  * Redistribution and use in source and binary forms, with or without
   7  * modification, are permitted provided that the following conditions
   8  * are met:
   9  * 1. Redistributions of source code must retain the above copyright
  10  *    notice, this list of conditions and the following disclaimer.
  11  * 2. Redistributions in binary form must reproduce the above copyright
  12  *    notice, this list of conditions and the following disclaimer in the
  13  *    documentation and/or other materials provided with the distribution.
  14  *
  15  * THIS SOFTWARE IS PROVIDED BY APPLE INC. ``AS IS'' AND ANY
  16  * EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
  17  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
  18  * PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL APPLE INC. OR
  19  * CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,
  20  * EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
  21  * PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR
  22  * PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY
  23  * OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
  24  * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
  25  * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
  26  */
  27
  28 #include "config.h"
  29 #include "core/layout/LayoutTextTrackContainer.h"
  30
  31 #include "core/frame/DeprecatedScheduleStyleRecalcDuringLayout.h"
  32 #include "core/layout/LayoutVideo.h"
  33
  34 namespace blink {
  35
  36 LayoutTextTrackContainer::LayoutTextTrackContainer(Element* element)
  37     : LayoutBlockFlow(element)
  38     , m_fontSize(0)
  39 {
  40 }
  41
  42 void LayoutTextTrackContainer::layout()
  43 {
  44     LayoutBlockFlow::layout();
  45     if (style()->display() == NONE)
  46         return;
  47
  48     DeprecatedScheduleStyleRecalcDuringLayout marker(node()->document().lifecycle());
  49
  50     LayoutObject* mediaLayoutObject = parent();
  51     if (!mediaLayoutObject || !mediaLayoutObject->isVideo())
  52         return;
  53     if (updateSizes(toLayoutVideo(*mediaLayoutObject)))
  54         toElement(node())->setInlineStyleProperty(CSSPropertyFontSize, m_fontSize, CSSPrimitiveValue::UnitType::Pixels);
  55 }
  56
  57 bool LayoutTextTrackContainer::updateSizes(const LayoutVideo& videoLayoutObject)
  58 {
  59     // FIXME: The video size is used to calculate the font size (a workaround
  60     // for lack of per-spec vh/vw support) but the whole media element is used
  61     // for cue rendering. This is inconsistent. See also the somewhat related
  62     // spec bug: https://www.w3.org/Bugs/Public/show_bug.cgi?id=28105
  63     IntSize videoSize = videoLayoutObject.videoBox().size();
  64     if (m_videoSize == videoSize)
  65         return false;
  66     m_videoSize = videoSize;
  67
  68     float smallestDimension = std::min(m_videoSize.height(), m_videoSize.width());
  69
  70     float fontSize = smallestDimension * 0.05f;
  71     if (m_fontSize == fontSize)
  72         return false;
  73     m_fontSize = fontSize;
  74     return true;
  75 }
  76
  77 } // namespace blink