Source/WebCore/platform/ScrollableArea.cpp

/*
 * Copyright (c) 2010, Google Inc. All rights reserved.
 * Copyright (C) 2008, 2011 Apple Inc. All Rights Reserved.
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 * notice, this list of conditions and the following disclaimer.
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 * in the documentation and/or other materials provided with the
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 * contributors may be used to endorse or promote products derived from
 * this software without specific prior written permission.
 * 
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 * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
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#include "config.h"
#include "ScrollableArea.h"

#include "FloatPoint.h"
#include "PlatformWheelEvent.h"
#include "ScrollAnimator.h"
#include <wtf/PassOwnPtr.h>

namespace WebCore {

ScrollableArea::ScrollableArea()
    : m_scrollAnimator(ScrollAnimator::create(this))
    , m_constrainsScrollingToContentEdge(true)
{
}

ScrollableArea::~ScrollableArea()
{
}

bool ScrollableArea::scroll(ScrollDirection direction, ScrollGranularity granularity, float multiplier)
{
    ScrollbarOrientation orientation;
    Scrollbar* scrollbar;
    if (direction == ScrollUp || direction == ScrollDown) {
        orientation = VerticalScrollbar;
        scrollbar = verticalScrollbar();
    } else {
        orientation = HorizontalScrollbar;
        scrollbar = horizontalScrollbar();
    }

    if (!scrollbar)
        return false;

    float step = 0;
    switch (granularity) {
    case ScrollByLine:
        step = scrollbar->lineStep();
        break;
    case ScrollByPage:
        step = scrollbar->pageStep();
        break;
    case ScrollByDocument:
        step = scrollbar->totalSize();
        break;
    case ScrollByPixel:
        step = scrollbar->pixelStep();
        break;
    }

    if (direction == ScrollUp || direction == ScrollLeft)
        multiplier = -multiplier;

    return m_scrollAnimator->scroll(orientation, granularity, step, multiplier);
}

void ScrollableArea::scrollToOffsetWithoutAnimation(const FloatPoint& offset)
{
    m_scrollAnimator->scrollToOffsetWithoutAnimation(offset);
}

void ScrollableArea::scrollToOffsetWithoutAnimation(ScrollbarOrientation orientation, float offset)
{
    if (orientation == HorizontalScrollbar)
        scrollToXOffsetWithoutAnimation(offset);
    else
        scrollToYOffsetWithoutAnimation(offset);
}

void ScrollableArea::scrollToXOffsetWithoutAnimation(float x)
{
    scrollToOffsetWithoutAnimation(FloatPoint(x, m_scrollAnimator->currentPosition().y()));
}

void ScrollableArea::scrollToYOffsetWithoutAnimation(float y)
{
    scrollToOffsetWithoutAnimation(FloatPoint(m_scrollAnimator->currentPosition().x(), y));
}

void ScrollableArea::handleWheelEvent(PlatformWheelEvent& wheelEvent)
{
    m_scrollAnimator->handleWheelEvent(wheelEvent);
}

#if ENABLE(GESTURE_EVENTS)
void ScrollableArea::handleGestureEvent(const PlatformGestureEvent& gestureEvent)
{
    m_scrollAnimator->handleGestureEvent(gestureEvent);
}
#endif

void ScrollableArea::setScrollOffsetFromAnimation(const IntPoint& offset)
{
    // Tell the derived class to scroll its contents.
    setScrollOffset(offset);

    // Tell the scrollbars to update their thumb postions.
    if (Scrollbar* horizontalScrollbar = this->horizontalScrollbar())
        horizontalScrollbar->offsetDidChange();
    if (Scrollbar* verticalScrollbar = this->verticalScrollbar())
        verticalScrollbar->offsetDidChange();
}

} // namespace WebCore