Source/WebCore/rendering/RenderVideo.cpp

/*
 * Copyright (C) 2007, 2008, 2009, 2010 Apple Inc.  All rights reserved.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions
 * are met:
 * 1. Redistributions of source code must retain the above copyright
 *    notice, this list of conditions and the following disclaimer.
 * 2. Redistributions in binary form must reproduce the above copyright
 *    notice, this list of conditions and the following disclaimer in the
 *    documentation and/or other materials provided with the distribution.
 *
 * THIS SOFTWARE IS PROVIDED BY APPLE COMPUTER, INC. ``AS IS'' AND ANY
 * EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
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#include "config.h"

#if ENABLE(VIDEO)
#include "RenderVideo.h"

#include "Document.h"
#include "FrameView.h"
#include "GraphicsContext.h"
#include "HTMLNames.h"
#include "HTMLVideoElement.h"
#include "MediaPlayer.h"
#include "PaintInfo.h"
#include "RenderView.h"

#if USE(ACCELERATED_COMPOSITING)
#include "RenderLayer.h"
#include "RenderLayerBacking.h"
#endif

using namespace std;

namespace WebCore {

using namespace HTMLNames;

RenderVideo::RenderVideo(HTMLVideoElement* video)
    : RenderMedia(video)
{
    setIntrinsicSize(calculateIntrinsicSize());
}

RenderVideo::~RenderVideo()
{
    if (MediaPlayer* p = mediaElement()->player()) {
        p->setVisible(false);
        p->setFrameView(0);
    }
}

IntSize RenderVideo::defaultSize()
{
    // These values are specified in the spec.
    static const int cDefaultWidth = 300;
    static const int cDefaultHeight = 150;

    return IntSize(cDefaultWidth, cDefaultHeight);
}

void RenderVideo::intrinsicSizeChanged()
{
    if (videoElement()->shouldDisplayPosterImage())
        RenderMedia::intrinsicSizeChanged();
    updateIntrinsicSize(); 
}

void RenderVideo::updateIntrinsicSize()
{
    IntSize size = calculateIntrinsicSize();
    size.scale(style()->effectiveZoom());

    // Never set the element size to zero when in a media document.
    if (size.isEmpty() && node()->ownerDocument() && node()->ownerDocument()->isMediaDocument())
        return;

    if (size == intrinsicSize())
        return;

    setIntrinsicSize(size);
    setPreferredLogicalWidthsDirty(true);
    setNeedsLayout(true);
}
    
IntSize RenderVideo::calculateIntrinsicSize()
{
    HTMLVideoElement* video = videoElement();
    
    // Spec text from 4.8.6
    //
    // The intrinsic width of a video element's playback area is the intrinsic width 
    // of the video resource, if that is available; otherwise it is the intrinsic 
    // width of the poster frame, if that is available; otherwise it is 300 CSS pixels.
    //
    // The intrinsic height of a video element's playback area is the intrinsic height 
    // of the video resource, if that is available; otherwise it is the intrinsic 
    // height of the poster frame, if that is available; otherwise it is 150 CSS pixels.
    MediaPlayer* player = mediaElement()->player();
    if (player && video->readyState() >= HTMLVideoElement::HAVE_METADATA)
        return player->naturalSize();

    if (video->shouldDisplayPosterImage() && !m_cachedImageSize.isEmpty() && !imageResource()->errorOccurred())
        return m_cachedImageSize;

    // When the natural size of the video is unavailable, we use the provided
    // width and height attributes of the video element as the intrinsic size until
    // better values become available. 
    if (video->hasAttribute(widthAttr) && video->hasAttribute(heightAttr))
        return IntSize(video->width(), video->height());

    // <video> in standalone media documents should not use the default 300x150
    // size since they also have audio-only files. By setting the intrinsic
    // size to 300x1 the video will resize itself in these cases, and audio will
    // have the correct height (it needs to be > 0 for controls to render properly).
    if (video->ownerDocument() && video->ownerDocument()->isMediaDocument())
        return IntSize(defaultSize().width(), 1);

    return defaultSize();
}

void RenderVideo::imageChanged(WrappedImagePtr newImage, const IntRect* rect)
{
    RenderMedia::imageChanged(newImage, rect);

    // Cache the image intrinsic size so we can continue to use it to draw the image correctly
    // even if we know the video intrinsic size but aren't able to draw video frames yet
    // (we don't want to scale the poster to the video size without keeping aspect ratio).
    if (videoElement()->shouldDisplayPosterImage())
        m_cachedImageSize = intrinsicSize();

    // The intrinsic size is now that of the image, but in case we already had the
    // intrinsic size of the video we call this here to restore the video size.
    updateIntrinsicSize();
}

IntRect RenderVideo::videoBox() const
{
    if (m_cachedImageSize.isEmpty() && videoElement()->shouldDisplayPosterImage())
        return IntRect();

    IntSize elementSize;
    if (videoElement()->shouldDisplayPosterImage())
        elementSize = m_cachedImageSize;
    else
        elementSize = intrinsicSize();

    IntRect contentRect = contentBoxRect();
    if (elementSize.isEmpty() || contentRect.isEmpty())
        return IntRect();

    IntRect renderBox = contentRect;
    int ratio = renderBox.width() * elementSize.height() - renderBox.height() * elementSize.width();
    if (ratio > 0) {
        int newWidth = renderBox.height() * elementSize.width() / elementSize.height();
        // Just fill the whole area if the difference is one pixel or less (in both sides)
        if (renderBox.width() - newWidth > 2)
            renderBox.setWidth(newWidth);
        renderBox.move((contentRect.width() - renderBox.width()) / 2, 0);
    } else if (ratio < 0) {
        int newHeight = renderBox.width() * elementSize.height() / elementSize.width();
        if (renderBox.height() - newHeight > 2)
            renderBox.setHeight(newHeight);
        renderBox.move(0, (contentRect.height() - renderBox.height()) / 2);
    }

    return renderBox;
}

bool RenderVideo::shouldDisplayVideo() const
{
    return !videoElement()->shouldDisplayPosterImage();
}

void RenderVideo::paintReplaced(PaintInfo& paintInfo, int tx, int ty)
{
    MediaPlayer* mediaPlayer = mediaElement()->player();
    bool displayingPoster = videoElement()->shouldDisplayPosterImage();

    if (!displayingPoster) {
        if (!mediaPlayer)
            return;
        updatePlayer();
    }

    IntRect rect = videoBox();
    if (rect.isEmpty())
        return;
    rect.move(tx, ty);

    if (displayingPoster)
        paintIntoRect(paintInfo.context, rect);
    else if (document()->view() && document()->view()->paintBehavior() & PaintBehaviorFlattenCompositingLayers)
        mediaPlayer->paintCurrentFrameInContext(paintInfo.context, rect);
    else
        mediaPlayer->paint(paintInfo.context, rect);
}

void RenderVideo::layout()
{
    RenderMedia::layout();
    updatePlayer();
}
    
HTMLVideoElement* RenderVideo::videoElement() const
{
    ASSERT(node()->hasTagName(videoTag));
    return static_cast<HTMLVideoElement*>(node()); 
}

void RenderVideo::updateFromElement()
{
    RenderMedia::updateFromElement();
    updatePlayer();
}

void RenderVideo::updatePlayer()
{
    updateIntrinsicSize();

    MediaPlayer* mediaPlayer = mediaElement()->player();
    if (!mediaPlayer)
        return;

    if (!videoElement()->inActiveDocument()) {
        mediaPlayer->setVisible(false);
        return;
    }

#if USE(ACCELERATED_COMPOSITING)
    layer()->contentChanged(RenderLayer::VideoChanged);
#endif
    
    IntRect videoBounds = videoBox(); 
    mediaPlayer->setFrameView(document()->view());
    mediaPlayer->setSize(IntSize(videoBounds.width(), videoBounds.height()));
    mediaPlayer->setVisible(true);
}

int RenderVideo::computeReplacedLogicalWidth(bool includeMaxWidth) const
{
    return RenderReplaced::computeReplacedLogicalWidth(includeMaxWidth);
}

int RenderVideo::computeReplacedLogicalHeight() const
{
    return RenderReplaced::computeReplacedLogicalHeight();
}

int RenderVideo::minimumReplacedHeight() const 
{
    return RenderReplaced::minimumReplacedHeight(); 
}

#if USE(ACCELERATED_COMPOSITING)
bool RenderVideo::supportsAcceleratedRendering() const
{
    MediaPlayer* p = mediaElement()->player();
    if (p)
        return p->supportsAcceleratedRendering();

    return false;
}

void RenderVideo::acceleratedRenderingStateChanged()
{
    MediaPlayer* p = mediaElement()->player();
    if (p)
        p->acceleratedRenderingStateChanged();
}
#endif  // USE(ACCELERATED_COMPOSITING)

} // namespace WebCore

#endif