Source/WebCore/platform/graphics/IntRect.cpp

/*
 * Copyright (C) 2003, 2006, 2009 Apple Inc. All rights reserved.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions
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 *    notice, this list of conditions and the following disclaimer in the
 *    documentation and/or other materials provided with the distribution.
 *
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 * 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 APPLE INC. OR ITS CONTRIBUTORS
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#include "config.h"
#include "IntRect.h"

#include "FloatRect.h"
#include "LayoutRect.h"
#include <algorithm>
#include <wtf/CheckedArithmetic.h>
#include <wtf/text/TextStream.h>

namespace WebCore {

IntRect::IntRect(const FloatRect& r)
    : m_location(clampToInteger(r.x()), clampToInteger(r.y()))
    , m_size(clampToInteger(r.width()), clampToInteger(r.height()))
{
}

IntRect::IntRect(const LayoutRect& r)
    : m_location(r.x(), r.y())
    , m_size(r.width(), r.height())
{
}

bool IntRect::intersects(const IntRect& other) const
{
    // Checking emptiness handles negative widths as well as zero.
    return !isEmpty() && !other.isEmpty()
        && x() < other.maxX() && other.x() < maxX()
        && y() < other.maxY() && other.y() < maxY();
}

bool IntRect::contains(const IntRect& other) const
{
    return x() <= other.x() && maxX() >= other.maxX()
        && y() <= other.y() && maxY() >= other.maxY();
}

void IntRect::intersect(const IntRect& other)
{
    int l = std::max(x(), other.x());
    int t = std::max(y(), other.y());
    int r = std::min(maxX(), other.maxX());
    int b = std::min(maxY(), other.maxY());

    // Return a clean empty rectangle for non-intersecting cases.
    if (l >= r || t >= b) {
        l = 0;
        t = 0;
        r = 0;
        b = 0;
    }

    m_location.setX(l);
    m_location.setY(t);
    m_size.setWidth(r - l);
    m_size.setHeight(b - t);
}

void IntRect::unite(const IntRect& other)
{
    // Handle empty special cases first.
    if (other.isEmpty())
        return;
    if (isEmpty()) {
        *this = other;
        return;
    }

    int l = std::min(x(), other.x());
    int t = std::min(y(), other.y());
    int r = std::max(maxX(), other.maxX());
    int b = std::max(maxY(), other.maxY());

    m_location.setX(l);
    m_location.setY(t);
    m_size.setWidth(r - l);
    m_size.setHeight(b - t);
}

void IntRect::uniteIfNonZero(const IntRect& other)
{
    // Handle empty special cases first.
    if (!other.width() && !other.height())
        return;
    if (!width() && !height()) {
        *this = other;
        return;
    }

    int left = std::min(x(), other.x());
    int top = std::min(y(), other.y());
    int right = std::max(maxX(), other.maxX());
    int bottom = std::max(maxY(), other.maxY());

    m_location.setX(left);
    m_location.setY(top);
    m_size.setWidth(right - left);
    m_size.setHeight(bottom - top);
}

void IntRect::scale(float s)
{
    m_location.setX((int)(x() * s));
    m_location.setY((int)(y() * s));
    m_size.setWidth((int)(width() * s));
    m_size.setHeight((int)(height() * s));
}

static inline int distanceToInterval(int pos, int start, int end)
{
    if (pos < start)
        return start - pos;
    if (pos > end)
        return end - pos;
    return 0;
}

IntSize IntRect::differenceToPoint(const IntPoint& point) const
{
    int xdistance = distanceToInterval(point.x(), x(), maxX());
    int ydistance = distanceToInterval(point.y(), y(), maxY());
    return IntSize(xdistance, ydistance);
}

bool IntRect::isValid() const
{
    CheckedInt32 max = m_location.x();
    max += m_size.width();
    if (max.hasOverflowed())
        return false;
    max = m_location.y();
    max += m_size.height();
    return !max.hasOverflowed();
}

TextStream& operator<<(TextStream& ts, const IntRect& r)
{
    if (ts.hasFormattingFlag(TextStream::Formatting::SVGStyleRect))
        return ts << "at (" << r.x() << "," << r.y() << ") size " << r.width() << "x" << r.height();

    return ts << r.location() << " " << r.size();
}

} // namespace WebCore