Source/core/rendering/shapes/BoxShape.cpp

/*
 * Copyright (C) 2013 Adobe Systems Incorporated. All rights reserved.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions
 * are met:
 *
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 *    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 THE COPYRIGHT HOLDERS AND CONTRIBUTORS
 * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
 * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
 * FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE
 * COPYRIGHT HOLDER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT,
 * INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
 * (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR
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#include "config.h"
#include "core/rendering/shapes/BoxShape.h"

#include "wtf/MathExtras.h"

namespace WebCore {

LayoutRect BoxShape::shapeMarginLogicalBoundingBox() const
{
    FloatRect marginBounds(m_bounds.rect());
    if (shapeMargin() > 0)
        marginBounds.inflate(shapeMargin());
    return static_cast<LayoutRect>(marginBounds);
}

FloatRoundedRect BoxShape::shapeMarginBounds() const
{
    FloatRoundedRect marginBounds(m_bounds);
    if (shapeMargin() > 0) {
        marginBounds.inflate(shapeMargin());
        marginBounds.expandRadii(shapeMargin());
    }
    return marginBounds;
}

void BoxShape::getExcludedIntervals(LayoutUnit logicalTop, LayoutUnit logicalHeight, SegmentList& result) const
{
    const FloatRoundedRect& marginBounds = shapeMarginBounds();
    if (marginBounds.isEmpty() || !lineOverlapsShapeMarginBounds(logicalTop, logicalHeight))
        return;

    float y1 = logicalTop.toFloat();
    float y2 = (logicalTop + logicalHeight).toFloat();
    const FloatRect& rect = marginBounds.rect();

    if (!marginBounds.isRounded()) {
        result.append(LineSegment(marginBounds.rect().x(), marginBounds.rect().maxX()));
        return;
    }

    float topCornerMaxY = std::max<float>(marginBounds.topLeftCorner().maxY(), marginBounds.topRightCorner().maxY());
    float bottomCornerMinY = std::min<float>(marginBounds.bottomLeftCorner().y(), marginBounds.bottomRightCorner().y());

    if (topCornerMaxY <= bottomCornerMinY && y1 <= topCornerMaxY && y2 >= bottomCornerMinY) {
        result.append(LineSegment(rect.x(), rect.maxX()));
        return;
    }

    float x1 = rect.maxX();
    float x2 = rect.x();
    float minXIntercept;
    float maxXIntercept;

    if (y1 <= marginBounds.topLeftCorner().maxY() && y2 >= marginBounds.bottomLeftCorner().y())
        x1 = rect.x();

    if (y1 <= marginBounds.topRightCorner().maxY() && y2 >= marginBounds.bottomRightCorner().y())
        x2 = rect.maxX();

    if (marginBounds.xInterceptsAtY(y1, minXIntercept, maxXIntercept)) {
        x1 = std::min<float>(x1, minXIntercept);
        x2 = std::max<float>(x2, maxXIntercept);
    }

    if (marginBounds.xInterceptsAtY(y2, minXIntercept, maxXIntercept)) {
        x1 = std::min<float>(x1, minXIntercept);
        x2 = std::max<float>(x2, maxXIntercept);
    }

    ASSERT(x2 >= x1);
    result.append(LineSegment(x1, x2));
}

} // namespace WebCore